Breaking down some more components, adding tests.

* Some bug fixes found during testing/test repair.
* Trying to tease apart the various responsibilities of `metricNamer` into smaller chunks and adding tests for each individual chunk.
* Updating the `provider_test` and `series_registry_test` to fix failures.

pkg/custom-provider/basic_metric_lister.go

@@ -105,6 +105,7 @@ func (l *basicMetricLister) ListAllMetrics() (metricUpdateResult, error) {
 				return
 			}
 			errs <- nil
+			//Push into the channel: "this selector produced these series"
 			selectorSeriesChan <- selectorSeries{
 				selector: sel,
 				series:   series,
@@ -116,23 +117,32 @@ func (l *basicMetricLister) ListAllMetrics() (metricUpdateResult, error) {
 	seriesCacheByQuery := make(map[prom.Selector][]prom.Series)
 
 	// iterate through, blocking until we've got all results
+	// We know that, from above, we should have pushed one item into the channel
+	// for each namer. So here, we'll assume that we should receive one item per namer.
 	for range l.namers {
 		if err := <-errs; err != nil {
 			return result, fmt.Errorf("unable to update list of all metrics: %v", err)
 		}
+		//Receive from the channel: "this selector produced these series"
+		//We stuff that into this map so that we can collect the data as it arrives
+		//and then, once we've received it all, we can process it below.
 		if ss := <-selectorSeriesChan; ss.series != nil {
 			seriesCacheByQuery[ss.selector] = ss.series
 		}
 	}
 	close(errs)
 
+	//Now that we've collected all of the results into `seriesCacheByQuery`
+	//we can start processing them.
 	newSeries := make([][]prom.Series, len(l.namers))
 	for i, namer := range l.namers {
 		series, cached := seriesCacheByQuery[namer.Selector()]
 		if !cached {
 			return result, fmt.Errorf("unable to update list of all metrics: no metrics retrieved for query %q", namer.Selector())
 		}
-		newSeries[i] = namer.FilterSeries(series)
+		//Because namers provide a "post-filtering" option, it's not enough to
+		//simply take all the series that were produced. We need to further filter them.
+		newSeries[i] = namer.SeriesFilterer().FilterSeries(series)
 	}
 
 	glog.V(10).Infof("Set available metric list from Prometheus to: %v", newSeries)

pkg/custom-provider/external_provider.go

@@ -1,81 +1,81 @@
 package provider
 
-import (
-	"context"
-	"time"
+// import (
+// 	"context"
+// 	"time"
 
-	pmodel "github.com/prometheus/common/model"
+// 	pmodel "github.com/prometheus/common/model"
 
-	"github.com/kubernetes-incubator/custom-metrics-apiserver/pkg/provider"
+// 	"github.com/kubernetes-incubator/custom-metrics-apiserver/pkg/provider"
 
-	apimeta "k8s.io/apimachinery/pkg/api/meta"
-	"k8s.io/apimachinery/pkg/labels"
-	"k8s.io/client-go/dynamic"
-	"k8s.io/metrics/pkg/apis/external_metrics"
+// 	apimeta "k8s.io/apimachinery/pkg/api/meta"
+// 	"k8s.io/apimachinery/pkg/labels"
+// 	"k8s.io/client-go/dynamic"
+// 	"k8s.io/metrics/pkg/apis/external_metrics"
 
-	prom "github.com/directxman12/k8s-prometheus-adapter/pkg/client"
-)
+// 	prom "github.com/directxman12/k8s-prometheus-adapter/pkg/client"
+// )
 
-//TODO: Make sure everything has the proper licensing disclosure at the top.
-//TODO: I'd like to move these files into another directory, but the compiler was giving me
-//some static around unexported types. I'm going to leave things as-is for now, but it
-//might be worthwhile to, once the shared components are discovered, move some things around.
+// //TODO: Make sure everything has the proper licensing disclosure at the top.
+// //TODO: I'd like to move these files into another directory, but the compiler was giving me
+// //some static around unexported types. I'm going to leave things as-is for now, but it
+// //might be worthwhile to, once the shared components are discovered, move some things around.
 
-//TODO: Some of these members may not be necessary.
-//Some of them are definitely duplicated between the
-//external and custom providers. They should probably share
-//the same instances of these objects (especially the SeriesRegistry)
-//to cut down on unnecessary chatter/bookkeeping.
-type externalPrometheusProvider struct {
-	mapper          apimeta.RESTMapper
-	kubeClient      dynamic.Interface
-	promClient      prom.Client
-	queryBuilder    ExternalMetricQueryBuilder
-	metricConverter conv.MetricConverter
+// //TODO: Some of these members may not be necessary.
+// //Some of them are definitely duplicated between the
+// //external and custom providers. They should probably share
+// //the same instances of these objects (especially the SeriesRegistry)
+// //to cut down on unnecessary chatter/bookkeeping.
+// type externalPrometheusProvider struct {
+// 	mapper          apimeta.RESTMapper
+// 	kubeClient      dynamic.Interface
+// 	promClient      prom.Client
+// 	queryBuilder    ExternalMetricQueryBuilder
+// 	metricConverter conv.MetricConverter
 
-	seriesRegistry SeriesRegistry
-}
+// 	seriesRegistry SeriesRegistry
+// }
 
-//TODO: It probably makes more sense to, once this is functional and complete, roll the
-//prometheusProvider and externalPrometheusProvider up into a single type
-//that implements both interfaces or provide a thin wrapper that composes them.
-//Just glancing at start.go looks like it would be much more straightforward
-//to do one of those two things instead of trying to run the two providers
-//independently.
+// //TODO: It probably makes more sense to, once this is functional and complete, roll the
+// //prometheusProvider and externalPrometheusProvider up into a single type
+// //that implements both interfaces or provide a thin wrapper that composes them.
+// //Just glancing at start.go looks like it would be much more straightforward
+// //to do one of those two things instead of trying to run the two providers
+// //independently.
 
-func NewExternalPrometheusProvider(mapper apimeta.RESTMapper, kubeClient dynamic.Interface, promClient prom.Client, namers []MetricNamer, updateInterval time.Duration, metricConverter conv.MetricConverter, seriesRegistry SeriesRegistry) (provider.ExternalMetricsProvider, Runnable) {
+// func NewExternalPrometheusProvider(mapper apimeta.RESTMapper, kubeClient dynamic.Interface, promClient prom.Client, namers []MetricNamer, updateInterval time.Duration, metricConverter conv.MetricConverter, seriesRegistry SeriesRegistry) (provider.ExternalMetricsProvider, Runnable) {
 
-	return &externalPrometheusProvider{
-		mapper:          mapper,
-		kubeClient:      kubeClient,
-		promClient:      promClient,
-		metricConverter: metricConverter,
-		seriesRegistry:  seriesRegistry,
-	}, lister
-}
+// 	return &externalPrometheusProvider{
+// 		mapper:          mapper,
+// 		kubeClient:      kubeClient,
+// 		promClient:      promClient,
+// 		metricConverter: metricConverter,
+// 		seriesRegistry:  seriesRegistry,
+// 	}, lister
+// }
 
-func (p *externalPrometheusProvider) GetExternalMetric(namespace string, metricName string, metricSelector labels.Selector) (*external_metrics.ExternalMetricValueList, error) {
-	selector, found := p.seriesRegistry.QueryForExternalMetric(metricInfo, metricSelector)
+// func (p *externalPrometheusProvider) GetExternalMetric(namespace string, metricName string, metricSelector labels.Selector) (*external_metrics.ExternalMetricValueList, error) {
+// 	selector, found := p.seriesRegistry.QueryForExternalMetric(metricInfo, metricSelector)
 
-	if !found {
-		return &external_metrics.ExternalMetricValueList{
-			Items: []external_metrics.ExternalMetricValue{},
-		}, nil
-	}
-	// query := p.queryBuilder.BuildPrometheusQuery(namespace, metricName, metricSelector, queryMetadata)
+// 	if !found {
+// 		return &external_metrics.ExternalMetricValueList{
+// 			Items: []external_metrics.ExternalMetricValue{},
+// 		}, nil
+// 	}
+// 	// query := p.queryBuilder.BuildPrometheusQuery(namespace, metricName, metricSelector, queryMetadata)
 
-	//TODO: I don't yet know what a context is, but apparently I should use a real one.
-	queryResults, err := p.promClient.Query(context.TODO(), pmodel.Now(), selector)
+// 	//TODO: I don't yet know what a context is, but apparently I should use a real one.
+// 	queryResults, err := p.promClient.Query(context.TODO(), pmodel.Now(), selector)
 
-	if err != nil {
-		//TODO: Is this how folks normally deal w/ errors? Just propagate them upwards?
-		//I should go look at what the customProvider does.
-		return nil, err
-	}
+// 	if err != nil {
+// 		//TODO: Is this how folks normally deal w/ errors? Just propagate them upwards?
+// 		//I should go look at what the customProvider does.
+// 		return nil, err
+// 	}
 
-	return p.metricConverter.Convert(queryMetadata, queryResults)
-}
+// 	return p.metricConverter.Convert(queryMetadata, queryResults)
+// }
 
-func (p *externalPrometheusProvider) ListAllExternalMetrics() []provider.ExternalMetricInfo {
-	return p.seriesRegistry.ListAllExternalMetrics()
-}
+// func (p *externalPrometheusProvider) ListAllExternalMetrics() []provider.ExternalMetricInfo {
+// 	return p.seriesRegistry.ListAllExternalMetrics()
+// }

pkg/custom-provider/label_group_resource_extractor.go

@@ -0,0 +1,83 @@
+package provider
+
+import (
+	"bytes"
+	"fmt"
+	"regexp"
+	"text/template"
+
+	apimeta "k8s.io/apimachinery/pkg/api/meta"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+
+	pmodel "github.com/prometheus/common/model"
+)
+
+// labelGroupResExtractor extracts schema.GroupResources from series labels.
+type labelGroupResExtractor struct {
+	regex *regexp.Regexp
+
+	resourceInd int
+	groupInd    *int
+	mapper      apimeta.RESTMapper
+}
+
+// newLabelGroupResExtractor creates a new labelGroupResExtractor for labels whose form
+// matches the given template.  It does so by creating a regular expression from the template,
+// so anything in the template which limits resource or group name length will cause issues.
+func newLabelGroupResExtractor(labelTemplate *template.Template) (*labelGroupResExtractor, error) {
+	labelRegexBuff := new(bytes.Buffer)
+	if err := labelTemplate.Execute(labelRegexBuff, schema.GroupResource{"(?P<group>.+?)", "(?P<resource>.+?)"}); err != nil {
+		return nil, fmt.Errorf("unable to convert label template to matcher: %v", err)
+	}
+	if labelRegexBuff.Len() == 0 {
+		return nil, fmt.Errorf("unable to convert label template to matcher: empty template")
+	}
+	labelRegexRaw := "^" + labelRegexBuff.String() + "$"
+	labelRegex, err := regexp.Compile(labelRegexRaw)
+	if err != nil {
+		return nil, fmt.Errorf("unable to convert label template to matcher: %v", err)
+	}
+
+	var groupInd *int
+	var resInd *int
+
+	for i, name := range labelRegex.SubexpNames() {
+		switch name {
+		case "group":
+			ind := i // copy to avoid iteration variable reference
+			groupInd = &ind
+		case "resource":
+			ind := i // copy to avoid iteration variable reference
+			resInd = &ind
+		}
+	}
+
+	if resInd == nil {
+		return nil, fmt.Errorf("must include at least `{{.Resource}}` in the label template")
+	}
+
+	return &labelGroupResExtractor{
+		regex:       labelRegex,
+		resourceInd: *resInd,
+		groupInd:    groupInd,
+	}, nil
+}
+
+// GroupResourceForLabel extracts a schema.GroupResource from the given label, if possible.
+// The second argument indicates whether or not a potential group-resource was found in this label.
+func (e *labelGroupResExtractor) GroupResourceForLabel(lbl pmodel.LabelName) (schema.GroupResource, bool) {
+	matchGroups := e.regex.FindStringSubmatch(string(lbl))
+	if matchGroups != nil {
+		group := ""
+		if e.groupInd != nil {
+			group = matchGroups[*e.groupInd]
+		}
+
+		return schema.GroupResource{
+			Group:    group,
+			Resource: matchGroups[e.resourceInd],
+		}, true
+	}
+
+	return schema.GroupResource{}, false
+}

pkg/custom-provider/metric_name_converter.go

@@ -0,0 +1,60 @@
+package provider
+
+import (
+	"fmt"
+	"regexp"
+
+	prom "github.com/directxman12/k8s-prometheus-adapter/pkg/client"
+	"github.com/directxman12/k8s-prometheus-adapter/pkg/config"
+)
+
+type MetricNameConverter interface {
+	GetMetricNameForSeries(series prom.Series) (string, error)
+}
+
+type metricNameConverter struct {
+	nameMatches *regexp.Regexp
+	nameAs      string
+}
+
+func NewMetricNameConverter(mapping config.NameMapping) (MetricNameConverter, error) {
+	var nameMatches *regexp.Regexp
+	var err error
+	if mapping.Matches != "" {
+		nameMatches, err = regexp.Compile(mapping.Matches)
+		if err != nil {
+			return nil, fmt.Errorf("unable to compile series name match expression %q: %v", mapping.Matches, err)
+		}
+	} else {
+		// this will always succeed
+		nameMatches = regexp.MustCompile(".*")
+	}
+	nameAs := mapping.As
+	if nameAs == "" {
+		// check if we have an obvious default
+		subexpNames := nameMatches.SubexpNames()
+		if len(subexpNames) == 1 {
+			// no capture groups, use the whole thing
+			nameAs = "$0"
+		} else if len(subexpNames) == 2 {
+			// one capture group, use that
+			nameAs = "$1"
+		} else {
+			return nil, fmt.Errorf("must specify an 'as' value for name matcher %q", mapping.Matches)
+		}
+	}
+
+	return &metricNameConverter{
+		nameMatches: nameMatches,
+		nameAs:      nameAs,
+	}, nil
+}
+
+func (c *metricNameConverter) GetMetricNameForSeries(series prom.Series) (string, error) {
+	matches := c.nameMatches.FindStringSubmatchIndex(series.Name)
+	if matches == nil {
+		return "", fmt.Errorf("series name %q did not match expected pattern %q", series.Name, c.nameMatches.String())
+	}
+	outNameBytes := c.nameMatches.ExpandString(nil, c.nameAs, series.Name, matches)
+	return string(outNameBytes), nil
+}

pkg/custom-provider/metric_name_converter_test.go

@@ -0,0 +1,85 @@
+package provider
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	prom "github.com/directxman12/k8s-prometheus-adapter/pkg/client"
+	config "github.com/directxman12/k8s-prometheus-adapter/pkg/config"
+)
+
+func TestWhenNoMappingMetricNameIsUnaltered(t *testing.T) {
+	emptyMapping := config.NameMapping{}
+	RunTest(t, emptyMapping, "my_series", "my_series")
+	RunTest(t, emptyMapping, "your_series", "your_series")
+}
+
+func TestWhenMappingWithOneCaptureGroupMetricNameIsCorrect(t *testing.T) {
+	mapping := config.NameMapping{
+		Matches: "my_(.*)",
+		As:      "your_$1",
+	}
+
+	RunTest(t, mapping, "my_requests_per_second", "your_requests_per_second")
+}
+
+func TestWhenMappingWithMultipleCaptureGroupsMetricNameIsCorrect(t *testing.T) {
+	//ExpandString has some strange behavior when using the $1, $2 syntax
+	//Specifically, it doesn't return the expected values for templates like:
+	//$1_$2
+	//You can work around it by using the ${1} syntax.
+	mapping := config.NameMapping{
+		Matches: "my_([^_]+)_([^_]+)",
+		As:      "your_${1}_is_${2}_large",
+	}
+
+	RunTest(t, mapping, "my_horse_very", "your_horse_is_very_large")
+	RunTest(t, mapping, "my_dog_not", "your_dog_is_not_large")
+}
+
+func TestAsCanBeInferred(t *testing.T) {
+	//When we've got one capture group, we should infer that as the target.
+	mapping := config.NameMapping{
+		Matches: "my_(.+)",
+	}
+
+	RunTest(t, mapping, "my_test_metric", "test_metric")
+
+	//When we have no capture groups, we should infer that the whole thing as the target.
+	mapping = config.NameMapping{
+		Matches: "my_metric",
+	}
+
+	RunTest(t, mapping, "my_metric", "my_metric")
+}
+
+func TestWhenAsCannotBeInferredError(t *testing.T) {
+	//More than one capture group should
+	//result in us giving up on making an educated guess.
+	mapping := config.NameMapping{
+		Matches: "my_([^_]+)_([^_]+)",
+	}
+
+	RunTestExpectingError(t, mapping, "my_horse_very")
+	RunTestExpectingError(t, mapping, "my_dog_not")
+}
+
+func RunTest(t *testing.T, mapping config.NameMapping, input string, expectedResult string) {
+	converter, err := NewMetricNameConverter(mapping)
+	require.NoError(t, err)
+
+	series := prom.Series{
+		Name: input,
+	}
+
+	actualResult, err := converter.GetMetricNameForSeries(series)
+	require.NoError(t, err)
+
+	require.Equal(t, expectedResult, actualResult)
+}
+
+func RunTestExpectingError(t *testing.T, mapping config.NameMapping, input string) {
+	_, err := NewMetricNameConverter(mapping)
+	require.Error(t, err)
+}

pkg/custom-provider/metric_namer.go

@@ -1,26 +1,17 @@
 package provider
 
 import (
-	"bytes"
 	"fmt"
-	"regexp"
-	"strings"
-	"sync"
-	"text/template"
 
-	"github.com/golang/glog"
-	"github.com/kubernetes-incubator/custom-metrics-apiserver/pkg/provider"
 	apimeta "k8s.io/apimachinery/pkg/api/meta"
 	"k8s.io/apimachinery/pkg/labels"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 
 	prom "github.com/directxman12/k8s-prometheus-adapter/pkg/client"
 	"github.com/directxman12/k8s-prometheus-adapter/pkg/config"
-	pmodel "github.com/prometheus/common/model"
 )
 
 var nsGroupResource = schema.GroupResource{Resource: "namespaces"}
-var groupNameSanitizer = strings.NewReplacer(".", "_", "-", "_")
 
 // MetricNamer knows how to convert Prometheus series names and label names to
 // metrics API resources, and vice-versa.  MetricNamers should be safe to access
@@ -34,146 +25,37 @@ type MetricNamer interface {
 	// FilterSeries checks to see which of the given series match any additional
 	// constrains beyond the series query.  It's assumed that the series given
 	// already matche the series query.
-	FilterSeries(series []prom.Series) []prom.Series
-	// ResourcesForSeries returns the group-resources associated with the given series,
-	// as well as whether or not the given series has the "namespace" resource).
-	ResourcesForSeries(series prom.Series) (res []schema.GroupResource, namespaced bool)
-	// LabelForResource returns the appropriate label for the given resource.
-	LabelForResource(resource schema.GroupResource) (pmodel.LabelName, error)
+	// FilterSeries(series []prom.Series) []prom.Series
+	SeriesFilterer() SeriesFilterer
+	ResourceConverter() ResourceConverter
+
 	// MetricNameForSeries returns the name (as presented in the API) for a given series.
-	MetricNameForSeries(series prom.Series) (string, error)
+	// MetricNameForSeries(series prom.Series) (string, error)
 	// QueryForSeries returns the query for a given series (not API metric name), with
 	// the given namespace name (if relevant), resource, and resource names.
 	QueryForSeries(series string, resource schema.GroupResource, namespace string, names ...string) (prom.Selector, error)
 	QueryForExternalSeries(series string, metricSelector labels.Selector) (prom.Selector, error)
+	IdentifySeries(series prom.Series) (seriesIdentity, error)
 }
 
-// labelGroupResExtractor extracts schema.GroupResources from series labels.
-type labelGroupResExtractor struct {
-	regex *regexp.Regexp
-
-	resourceInd int
-	groupInd    *int
-	mapper      apimeta.RESTMapper
+type seriesIdentity struct {
+	resources  []schema.GroupResource
+	namespaced bool
+	name       string
 }
 
-// newLabelGroupResExtractor creates a new labelGroupResExtractor for labels whose form
-// matches the given template.  It does so by creating a regular expression from the template,
-// so anything in the template which limits resource or group name length will cause issues.
-func newLabelGroupResExtractor(labelTemplate *template.Template) (*labelGroupResExtractor, error) {
-	labelRegexBuff := new(bytes.Buffer)
-	if err := labelTemplate.Execute(labelRegexBuff, schema.GroupResource{"(?P<group>.+?)", "(?P<resource>.+?)"}); err != nil {
-		return nil, fmt.Errorf("unable to convert label template to matcher: %v", err)
-	}
-	if labelRegexBuff.Len() == 0 {
-		return nil, fmt.Errorf("unable to convert label template to matcher: empty template")
-	}
-	labelRegexRaw := "^" + labelRegexBuff.String() + "$"
-	labelRegex, err := regexp.Compile(labelRegexRaw)
-	if err != nil {
-		return nil, fmt.Errorf("unable to convert label template to matcher: %v", err)
-	}
-
-	var groupInd *int
-	var resInd *int
-
-	for i, name := range labelRegex.SubexpNames() {
-		switch name {
-		case "group":
-			ind := i // copy to avoid iteration variable reference
-			groupInd = &ind
-		case "resource":
-			ind := i // copy to avoid iteration variable reference
-			resInd = &ind
-		}
-	}
-
-	if resInd == nil {
-		return nil, fmt.Errorf("must include at least `{{.Resource}}` in the label template")
-	}
-
-	return &labelGroupResExtractor{
-		regex:       labelRegex,
-		resourceInd: *resInd,
-		groupInd:    groupInd,
-	}, nil
-}
-
-// GroupResourceForLabel extracts a schema.GroupResource from the given label, if possible.
-// The second argument indicates whether or not a potential group-resource was found in this label.
-func (e *labelGroupResExtractor) GroupResourceForLabel(lbl pmodel.LabelName) (schema.GroupResource, bool) {
-	matchGroups := e.regex.FindStringSubmatch(string(lbl))
-	if matchGroups != nil {
-		group := ""
-		if e.groupInd != nil {
-			group = matchGroups[*e.groupInd]
-		}
-
-		return schema.GroupResource{
-			Group:    group,
-			Resource: matchGroups[e.resourceInd],
-		}, true
-	}
-
-	return schema.GroupResource{}, false
-}
-
-func (r *metricNamer) Selector() prom.Selector {
-	return r.seriesQuery
-}
-
-// reMatcher either positively or negatively matches a regex
-type reMatcher struct {
-	regex    *regexp.Regexp
-	positive bool
-}
-
-func newReMatcher(cfg config.RegexFilter) (*reMatcher, error) {
-	if cfg.Is != "" && cfg.IsNot != "" {
-		return nil, fmt.Errorf("cannot have both an `is` (%q) and `isNot` (%q) expression in a single filter", cfg.Is, cfg.IsNot)
-	}
-	if cfg.Is == "" && cfg.IsNot == "" {
-		return nil, fmt.Errorf("must have either an `is` or `isNot` expression in a filter")
-	}
-
-	var positive bool
-	var regexRaw string
-	if cfg.Is != "" {
-		positive = true
-		regexRaw = cfg.Is
-	} else {
-		positive = false
-		regexRaw = cfg.IsNot
-	}
-
-	regex, err := regexp.Compile(regexRaw)
-	if err != nil {
-		return nil, fmt.Errorf("unable to compile series filter %q: %v", regexRaw, err)
-	}
-
-	return &reMatcher{
-		regex:    regex,
-		positive: positive,
-	}, nil
-}
-
-func (m *reMatcher) Matches(val string) bool {
-	return m.regex.MatchString(val) == m.positive
+func (n *metricNamer) Selector() prom.Selector {
+	return n.seriesQuery
 }
 
 type metricNamer struct {
-	seriesQuery          prom.Selector
-	labelTemplate        *template.Template
-	labelResExtractor    *labelGroupResExtractor
-	metricsQueryTemplate *template.Template
-	nameMatches          *regexp.Regexp
-	nameAs               string
-	seriesMatchers       []*reMatcher
+	seriesQuery prom.Selector
 
-	labelResourceMu sync.RWMutex
-	labelToResource map[pmodel.LabelName]schema.GroupResource
-	resourceToLabel map[schema.GroupResource]pmodel.LabelName
-	mapper          apimeta.RESTMapper
+	resourceConverter   ResourceConverter
+	queryBuilder        QueryBuilder
+	seriesFilterer      SeriesFilterer
+	metricNameConverter MetricNameConverter
+	mapper              apimeta.RESTMapper
 
 	metricType config.MetricType
 }
@@ -187,23 +69,26 @@ type queryTemplateArgs struct {
 	GroupBySlice      []string
 }
 
-func (n *metricNamer) FilterSeries(initialSeries []prom.Series) []prom.Series {
-	if len(n.seriesMatchers) == 0 {
-		return initialSeries
+func (n *metricNamer) IdentifySeries(series prom.Series) (seriesIdentity, error) {
+	// TODO: warn if it doesn't match any resources
+	resources, namespaced := n.resourceConverter.ResourcesForSeries(series)
+	name, err := n.metricNameConverter.GetMetricNameForSeries(series)
+
+	result := seriesIdentity{
+		resources:  resources,
+		namespaced: namespaced,
+		name:       name,
 	}
 
-	finalSeries := make([]prom.Series, 0, len(initialSeries))
-SeriesLoop:
-	for _, series := range initialSeries {
-		for _, matcher := range n.seriesMatchers {
-			if !matcher.Matches(series.Name) {
-				continue SeriesLoop
-			}
-		}
-		finalSeries = append(finalSeries, series)
-	}
+	return result, err
+}
 
-	return finalSeries
+func (n *metricNamer) SeriesFilterer() SeriesFilterer {
+	return n.seriesFilterer
+}
+
+func (n *metricNamer) ResourceConverter() ResourceConverter {
+	return n.resourceConverter
 }
 
 func (n *metricNamer) createQueryPartsFromSelector(metricSelector labels.Selector) []queryPart {
@@ -240,7 +125,7 @@ func (n *metricNamer) buildNamespaceQueryPartForSeries(namespace string) (queryP
 	//If we've been given a namespace, then we need to set up
 	//the label requirements to target that namespace.
 	if namespace != "" {
-		namespaceLbl, err := n.LabelForResource(nsGroupResource)
+		namespaceLbl, err := n.ResourceConverter().LabelForResource(nsGroupResource)
 		if err != nil {
 			return result, err
 		}
@@ -261,7 +146,7 @@ func (n *metricNamer) buildResourceQueryPartForSeries(resource schema.GroupResou
 
 	//If we've been given a resource, then we need to set up
 	//the label requirements to target that resource.
-	resourceLbl, err := n.LabelForResource(resource)
+	resourceLbl, err := n.ResourceConverter().LabelForResource(resource)
 	if err != nil {
 		return result, err
 	}
@@ -274,34 +159,6 @@ func (n *metricNamer) buildResourceQueryPartForSeries(resource schema.GroupResou
 	return result, nil
 }
 
-func (n *metricNamer) processQueryParts(queryParts []queryPart) ([]string, map[string][]string) {
-	//Contains the expressions that we want to include as part of the query to Prometheus.
-	//e.g. "namespace=my-namespace"
-	//e.g. "some_label=some-value"
-	var exprs []string
-
-	//Contains the list of label values we're targeting, by namespace.
-	//e.g. "some_label" => ["value-one", "value-two"]
-	valuesByName := map[string][]string{}
-
-	//Convert our query parts into template arguments.
-	for _, qPart := range queryParts {
-		targetValue := qPart.values[0]
-		matcher := prom.LabelEq
-
-		if len(qPart.values) > 1 {
-			targetValue = strings.Join(qPart.values, "|")
-			matcher = prom.LabelMatches
-		}
-
-		expression := matcher(qPart.labelName, targetValue)
-		exprs = append(exprs, expression)
-		valuesByName[qPart.labelName] = qPart.values
-	}
-
-	return exprs, valuesByName
-}
-
 func (n *metricNamer) QueryForSeries(series string, resource schema.GroupResource, namespace string, names ...string) (prom.Selector, error) {
 	queryParts := []queryPart{}
 
@@ -321,259 +178,51 @@ func (n *metricNamer) QueryForSeries(series string, resource schema.GroupResourc
 
 	queryParts = append(queryParts, resourceQueryPart)
 
-	//Convert our query parts into the types we need for our template.
-	exprs, valuesByName := n.processQueryParts(queryParts)
-
-	args := queryTemplateArgs{
-		Series:            series,
-		LabelMatchers:     strings.Join(exprs, ","),
-		LabelValuesByName: valuesByName,
-		GroupBy:           resourceQueryPart.labelName,
-		GroupBySlice:      []string{resourceQueryPart.labelName},
-	}
-
-	selector, err := n.createSelectorFromTemplateArgs(args)
-	if err != nil {
-		return "", err
-	}
-
-	return selector, nil
-}
-
-func (n *metricNamer) createSelectorFromTemplateArgs(args queryTemplateArgs) (prom.Selector, error) {
-	//Turn our template arguments into a Selector.
-	queryBuff := new(bytes.Buffer)
-	if err := n.metricsQueryTemplate.Execute(queryBuff, args); err != nil {
-		return "", err
-	}
-
-	if queryBuff.Len() == 0 {
-		return "", fmt.Errorf("empty query produced by metrics query template")
-	}
-
-	return prom.Selector(queryBuff.String()), nil
-}
-
-func (n *metricNamer) ResourcesForSeries(series prom.Series) ([]schema.GroupResource, bool) {
-	// use an updates map to avoid having to drop the read lock to update the cache
-	// until the end.  Since we'll probably have few updates after the first run,
-	// this should mean that we rarely have to hold the write lock.
-	var resources []schema.GroupResource
-	updates := make(map[pmodel.LabelName]schema.GroupResource)
-	namespaced := false
-
-	// use an anon func to get the right defer behavior
-	func() {
-		n.labelResourceMu.RLock()
-		defer n.labelResourceMu.RUnlock()
-
-		for lbl := range series.Labels {
-			var groupRes schema.GroupResource
-			var ok bool
-
-			// check if we have an override
-			if groupRes, ok = n.labelToResource[lbl]; ok {
-				resources = append(resources, groupRes)
-			} else if groupRes, ok = updates[lbl]; ok {
-				resources = append(resources, groupRes)
-			} else if n.labelResExtractor != nil {
-				// if not, check if it matches the form we expect, and if so,
-				// convert to a group-resource.
-				if groupRes, ok = n.labelResExtractor.GroupResourceForLabel(lbl); ok {
-					info, _, err := provider.CustomMetricInfo{GroupResource: groupRes}.Normalized(n.mapper)
-					if err != nil {
-						glog.Errorf("unable to normalize group-resource %s from label %q, skipping: %v", groupRes.String(), lbl, err)
-						continue
-					}
-
-					groupRes = info.GroupResource
-					resources = append(resources, groupRes)
-					updates[lbl] = groupRes
-				}
-			}
-
-			if groupRes == nsGroupResource {
-				namespaced = true
-			}
-		}
-	}()
-
-	// update the cache for next time.  This should only be called by discovery,
-	// so we don't really have to worry about the grap between read and write locks
-	// (plus, we don't care if someone else updates the cache first, since the results
-	// are necessarily the same, so at most we've done extra work).
-	if len(updates) > 0 {
-		n.labelResourceMu.Lock()
-		defer n.labelResourceMu.Unlock()
-
-		for lbl, groupRes := range updates {
-			n.labelToResource[lbl] = groupRes
-		}
-	}
-
-	return resources, namespaced
-}
-
-func (n *metricNamer) LabelForResource(resource schema.GroupResource) (pmodel.LabelName, error) {
-	n.labelResourceMu.RLock()
-	// check if we have a cached copy or override
-	lbl, ok := n.resourceToLabel[resource]
-	n.labelResourceMu.RUnlock() // release before we call makeLabelForResource
-	if ok {
-		return lbl, nil
-	}
-
-	// NB: we don't actually care about the gap between releasing read lock
-	// and acquiring the write lock -- if we do duplicate work sometimes, so be
-	// it, as long as we're correct.
-
-	// otherwise, use the template and save the result
-	lbl, err := n.makeLabelForResource(resource)
-	if err != nil {
-		return "", fmt.Errorf("unable to convert resource %s into label: %v", resource.String(), err)
-	}
-	return lbl, nil
-}
-
-// makeLabelForResource constructs a label name for the given resource, and saves the result.
-// It must *not* be called under an existing lock.
-func (n *metricNamer) makeLabelForResource(resource schema.GroupResource) (pmodel.LabelName, error) {
-	if n.labelTemplate == nil {
-		return "", fmt.Errorf("no generic resource label form specified for this metric")
-	}
-	buff := new(bytes.Buffer)
-
-	singularRes, err := n.mapper.ResourceSingularizer(resource.Resource)
-	if err != nil {
-		return "", fmt.Errorf("unable to singularize resource %s: %v", resource.String(), err)
-	}
-	convResource := schema.GroupResource{
-		Group:    groupNameSanitizer.Replace(resource.Group),
-		Resource: singularRes,
-	}
-
-	if err := n.labelTemplate.Execute(buff, convResource); err != nil {
-		return "", err
-	}
-	if buff.Len() == 0 {
-		return "", fmt.Errorf("empty label produced by label template")
-	}
-	lbl := pmodel.LabelName(buff.String())
-
-	n.labelResourceMu.Lock()
-	defer n.labelResourceMu.Unlock()
-
-	n.resourceToLabel[resource] = lbl
-	n.labelToResource[lbl] = resource
-	return lbl, nil
-}
-
-func (n *metricNamer) MetricNameForSeries(series prom.Series) (string, error) {
-	matches := n.nameMatches.FindStringSubmatchIndex(series.Name)
-	if matches == nil {
-		return "", fmt.Errorf("series name %q did not match expected pattern %q", series.Name, n.nameMatches.String())
-	}
-	outNameBytes := n.nameMatches.ExpandString(nil, n.nameAs, series.Name, matches)
-	return string(outNameBytes), nil
+	return n.queryBuilder.BuildSelector(series, resourceQueryPart.labelName, []string{resourceQueryPart.labelName}, queryParts)
 }
 
 // NamersFromConfig produces a MetricNamer for each rule in the given config.
 func NamersFromConfig(cfg *config.MetricsDiscoveryConfig, mapper apimeta.RESTMapper) ([]MetricNamer, error) {
 	namers := make([]MetricNamer, len(cfg.Rules))
-
 	for i, rule := range cfg.Rules {
-		var labelTemplate *template.Template
-		var labelResExtractor *labelGroupResExtractor
 		var err error
-		if rule.Resources.Template != "" {
-			labelTemplate, err = template.New("resource-label").Delims("<<", ">>").Parse(rule.Resources.Template)
-			if err != nil {
-				return nil, fmt.Errorf("unable to parse label template %q associated with series query %q: %v", rule.Resources.Template, rule.SeriesQuery, err)
-			}
 
-			labelResExtractor, err = newLabelGroupResExtractor(labelTemplate)
-			if err != nil {
-				return nil, fmt.Errorf("unable to generate label format from template %q associated with series query %q: %v", rule.Resources.Template, rule.SeriesQuery, err)
-			}
-		}
-
-		metricsQueryTemplate, err := template.New("metrics-query").Delims("<<", ">>").Parse(rule.MetricsQuery)
+		resourceConverter, err := NewResourceConverter(rule.Resources.Template, rule.Resources.Overrides, mapper)
 		if err != nil {
-			return nil, fmt.Errorf("unable to parse metrics query template %q associated with series query %q: %v", rule.MetricsQuery, rule.SeriesQuery, err)
+			return nil, fmt.Errorf("unable to create ResourceConverter associated with series query %q: %v", rule.SeriesQuery, err)
 		}
 
-		seriesMatchers := make([]*reMatcher, len(rule.SeriesFilters))
-		for i, filterRaw := range rule.SeriesFilters {
-			matcher, err := newReMatcher(filterRaw)
-			if err != nil {
-				return nil, fmt.Errorf("unable to generate series name filter associated with series query %q: %v", rule.SeriesQuery, err)
-			}
-			seriesMatchers[i] = matcher
-		}
-		if rule.Name.Matches != "" {
-			matcher, err := newReMatcher(config.RegexFilter{Is: rule.Name.Matches})
-			if err != nil {
-				return nil, fmt.Errorf("unable to generate series name filter from name rules associated with series query %q: %v", rule.SeriesQuery, err)
-			}
-			seriesMatchers = append(seriesMatchers, matcher)
+		queryBuilder, err := NewQueryBuilder(rule.MetricsQuery)
+		if err != nil {
+			return nil, fmt.Errorf("unable to create a QueryBuilder associated with series query %q: %v", rule.SeriesQuery, err)
 		}
 
-		var nameMatches *regexp.Regexp
-		if rule.Name.Matches != "" {
-			nameMatches, err = regexp.Compile(rule.Name.Matches)
-			if err != nil {
-				return nil, fmt.Errorf("unable to compile series name match expression %q associated with series query %q: %v", rule.Name.Matches, rule.SeriesQuery, err)
-			}
-		} else {
-			// this will always succeed
-			nameMatches = regexp.MustCompile(".*")
+		seriesFilterer, err := NewSeriesFilterer(rule.SeriesFilters)
+		if err != nil {
+			return nil, fmt.Errorf("unable to create a SeriesFilter associated with series query %q: %v", rule.SeriesQuery, err)
 		}
-		nameAs := rule.Name.As
-		if nameAs == "" {
-			// check if we have an obvious default
-			subexpNames := nameMatches.SubexpNames()
-			if len(subexpNames) == 1 {
-				// no capture groups, use the whole thing
-				nameAs = "$0"
-			} else if len(subexpNames) == 2 {
-				// one capture group, use that
-				nameAs = "$1"
-			} else {
-				return nil, fmt.Errorf("must specify an 'as' value for name matcher %q associated with series query %q", rule.Name.Matches, rule.SeriesQuery)
+
+		if rule.Name.Matches != "" {
+			err := seriesFilterer.AddRequirement(config.RegexFilter{Is: rule.Name.Matches})
+			if err != nil {
+				return nil, fmt.Errorf("unable to apply the series name filter from name rules associated with series query %q: %v", rule.SeriesQuery, err)
 			}
 		}
 
+		metricNameConverter, err := NewMetricNameConverter(rule.Name)
+		if err != nil {
+			return nil, fmt.Errorf("unable to create a MetricNameConverter associated with series query %q: %v", rule.SeriesQuery, err)
+		}
+
 		namer := &metricNamer{
-			seriesQuery:          prom.Selector(rule.SeriesQuery),
-			labelTemplate:        labelTemplate,
-			labelResExtractor:    labelResExtractor,
-			metricsQueryTemplate: metricsQueryTemplate,
-			mapper:               mapper,
-			nameMatches:          nameMatches,
-			nameAs:               nameAs,
-			seriesMatchers:       seriesMatchers,
+			seriesQuery: prom.Selector(rule.SeriesQuery),
+			mapper:      mapper,
 
-			labelToResource: make(map[pmodel.LabelName]schema.GroupResource),
-			resourceToLabel: make(map[schema.GroupResource]pmodel.LabelName),
-
-			metricType: rule.MetricType,
-		}
-
-		// invert the structure for consistency with the template
-		for lbl, groupRes := range rule.Resources.Overrides {
-			infoRaw := provider.CustomMetricInfo{
-				GroupResource: schema.GroupResource{
-					Group:    groupRes.Group,
-					Resource: groupRes.Resource,
-				},
-			}
-			info, _, err := infoRaw.Normalized(mapper)
-			if err != nil {
-				return nil, fmt.Errorf("unable to normalize group-resource %v: %v", groupRes, err)
-			}
-
-			namer.labelToResource[pmodel.LabelName(lbl)] = info.GroupResource
-			namer.resourceToLabel[info.GroupResource] = pmodel.LabelName(lbl)
+			resourceConverter:   resourceConverter,
+			queryBuilder:        queryBuilder,
+			seriesFilterer:      seriesFilterer,
+			metricNameConverter: metricNameConverter,
+			metricType:          rule.MetricType,
 		}
 
 		namers[i] = namer
@@ -585,15 +234,7 @@ func NamersFromConfig(cfg *config.MetricsDiscoveryConfig, mapper apimeta.RESTMap
 func (n *metricNamer) QueryForExternalSeries(series string, metricSelector labels.Selector) (prom.Selector, error) {
 	queryParts := n.createQueryPartsFromSelector(metricSelector)
 
-	exprs, valuesByName := n.processQueryParts(queryParts)
-
-	args := queryTemplateArgs{
-		Series:            series,
-		LabelMatchers:     strings.Join(exprs, ","),
-		LabelValuesByName: valuesByName,
-	}
-
-	selector, err := n.createSelectorFromTemplateArgs(args)
+	selector, err := n.queryBuilder.BuildSelector(series, "", []string{}, queryParts)
 	if err != nil {
 		return "", err
 	}

pkg/custom-provider/periodic_metric_lister.go

@@ -55,14 +55,26 @@ func (l *periodicMetricLister) Run() {
 
 func (l *periodicMetricLister) RunUntil(stopChan <-chan struct{}) {
 	go wait.Until(func() {
-		if result, err := l.realLister.ListAllMetrics(); err != nil {
+		if err := l.updateMetrics(); err != nil {
 			utilruntime.HandleError(err)
-		} else {
-			l.mostRecentResult = result
 		}
 	}, l.updateInterval, stopChan)
 }
 
+func (l *periodicMetricLister) updateMetrics() error {
+	result, err := l.realLister.ListAllMetrics()
+
+	if err != nil {
+		return err
+	}
+
+	//Cache the result.
+	l.mostRecentResult = result
+	//Let our listener know we've got new data ready for them.
+	l.callback(result)
+	return nil
+}
+
 // func (l *periodicMetricLister) updateMetrics() (metricUpdateResult, error) {
 
 // 	result := metricUpdateResult{

pkg/custom-provider/provider.go

@@ -48,7 +48,9 @@ type prometheusProvider struct {
 
 func NewPrometheusProvider(mapper apimeta.RESTMapper, kubeClient dynamic.Interface, promClient prom.Client, namers []MetricNamer, updateInterval time.Duration) (provider.CustomMetricsProvider, Runnable) {
 	basicLister := NewBasicMetricLister(promClient, namers, updateInterval)
-	periodicLister, periodicRunnable := NewPeriodicMetricLister(basicLister, updateInterval)
+	//TODO: Be sure to run this runnable.
+	// periodicLister, periodicRunnable := NewPeriodicMetricLister(basicLister, updateInterval)
+	periodicLister, _ := NewPeriodicMetricLister(basicLister, updateInterval)
 
 	seriesRegistry := NewBasicSeriesRegistry(periodicLister, mapper)
 

pkg/custom-provider/provider_test.go

@@ -141,7 +141,9 @@ func TestListAllMetrics(t *testing.T) {
 	fakeProm.acceptibleInterval = pmodel.Interval{Start: startTime, End: 0}
 
 	// update the metrics (without actually calling RunUntil, so we can avoid timing issues)
-	lister := prov.(*prometheusProvider).SeriesRegistry.(*cachingMetricsLister)
+	lister := prov.(*prometheusProvider).SeriesRegistry.(*basicSeriesRegistry).metricLister.(*periodicMetricLister)
+
+	// lister := prov.(*prometheusProvider).SeriesRegistry.(*basicSeriesRegistry).metricLister.(*periodicMetricLister).realLister.(*basicMetricLister)
 	require.NoError(t, lister.updateMetrics())
 
 	// list/sort the metrics

pkg/custom-provider/query_builder.go

@@ -0,0 +1,96 @@
+package provider
+
+import (
+	"bytes"
+	"fmt"
+	"strings"
+	"text/template"
+
+	prom "github.com/directxman12/k8s-prometheus-adapter/pkg/client"
+)
+
+type QueryBuilder interface {
+	BuildSelector(seriesName string, groupBy string, groupBySlice []string, queryParts []queryPart) (prom.Selector, error)
+}
+
+type queryBuilder struct {
+	metricsQueryTemplate *template.Template
+}
+
+func NewQueryBuilder(metricsQuery string) (QueryBuilder, error) {
+	metricsQueryTemplate, err := template.New("metrics-query").Delims("<<", ">>").Parse(metricsQuery)
+	if err != nil {
+		return nil, fmt.Errorf("unable to parse metrics query template %q: %v", metricsQuery, err)
+	}
+
+	return &queryBuilder{
+		metricsQueryTemplate: metricsQueryTemplate,
+	}, nil
+}
+
+func (n *queryBuilder) BuildSelector(seriesName string, groupBy string, groupBySlice []string, queryParts []queryPart) (prom.Selector, error) {
+	//Convert our query parts into the types we need for our template.
+	exprs, valuesByName := n.processQueryParts(queryParts)
+
+	args := queryTemplateArgs{
+		Series:            seriesName,
+		LabelMatchers:     strings.Join(exprs, ","),
+		LabelValuesByName: valuesByName,
+		GroupBy:           groupBy,
+		GroupBySlice:      groupBySlice,
+	}
+
+	selector, err := n.createSelectorFromTemplateArgs(args)
+	if err != nil {
+		return "", err
+	}
+
+	return selector, nil
+}
+
+func (n *queryBuilder) createSelectorFromTemplateArgs(args queryTemplateArgs) (prom.Selector, error) {
+	//Turn our template arguments into a Selector.
+	queryBuff := new(bytes.Buffer)
+	if err := n.metricsQueryTemplate.Execute(queryBuff, args); err != nil {
+		return "", err
+	}
+
+	if queryBuff.Len() == 0 {
+		return "", fmt.Errorf("empty query produced by metrics query template")
+	}
+
+	return prom.Selector(queryBuff.String()), nil
+}
+
+func (n *queryBuilder) processQueryParts(queryParts []queryPart) ([]string, map[string][]string) {
+	//Contains the expressions that we want to include as part of the query to Prometheus.
+	//e.g. "namespace=my-namespace"
+	//e.g. "some_label=some-value"
+	var exprs []string
+
+	//Contains the list of label values we're targeting, by namespace.
+	//e.g. "some_label" => ["value-one", "value-two"]
+	valuesByName := map[string][]string{}
+
+	//Convert our query parts into template arguments.
+	for _, qPart := range queryParts {
+		//Be resilient against bad inputs.
+		//We obviously can't generate label filters for these cases.
+		if qPart.labelName == "" || len(qPart.values) == 0 {
+			continue
+		}
+		targetValue := qPart.values[0]
+		matcher := prom.LabelEq
+
+		if len(qPart.values) > 1 {
+			targetValue = strings.Join(qPart.values, "|")
+			matcher = prom.LabelMatches
+		}
+
+		expression := matcher(qPart.labelName, targetValue)
+		exprs = append(exprs, expression)
+		valuesByName[qPart.labelName] = qPart.values
+	}
+
+	return exprs, valuesByName
+}

pkg/custom-provider/query_builder_test.go

@@ -0,0 +1,64 @@
+package provider
+
+import (
+	"testing"
+
+	"github.com/directxman12/k8s-prometheus-adapter/pkg/client"
+	"github.com/stretchr/testify/require"
+)
+
+func TestSimpleQuery(t *testing.T) {
+	builder, _ := NewQueryBuilder("rate(<<.Series>>{<<.LabelMatchers>>}[2m])")
+
+	// builder, _ := NewQueryBuilder("sum(rate(<<.Series>>{<<.LabelMatchers>>,static_label!=\"static_value\"}[2m])) by (<<.GroupBy>>)")
+	selector, _ := builder.BuildSelector("my_series", "", []string{}, []queryPart{})
+
+	expectation := client.Selector("rate(my_series{}[2m])")
+	require.Equal(t, selector, expectation)
+}
+
+func TestSimpleQueryWithOneLabelValue(t *testing.T) {
+	builder, _ := NewQueryBuilder("rate(<<.Series>>{<<.LabelMatchers>>}[2m])")
+
+	// builder, _ := NewQueryBuilder("sum(rate(<<.Series>>{<<.LabelMatchers>>,static_label!=\"static_value\"}[2m])) by (<<.GroupBy>>)")
+	selector, _ := builder.BuildSelector("my_series", "", []string{}, []queryPart{
+		queryPart{
+			labelName: "target_label",
+			values:    []string{"one"},
+		},
+	})
+
+	expectation := client.Selector("rate(my_series{target_label=\"one\"}[2m])")
+	require.Equal(t, selector, expectation)
+}
+
+func TestSimpleQueryWithMultipleLabelValues(t *testing.T) {
+	builder, _ := NewQueryBuilder("rate(<<.Series>>{<<.LabelMatchers>>}[2m])")
+
+	// builder, _ := NewQueryBuilder("sum(rate(<<.Series>>{<<.LabelMatchers>>,static_label!=\"static_value\"}[2m])) by (<<.GroupBy>>)")
+	selector, _ := builder.BuildSelector("my_series", "", []string{}, []queryPart{
+		queryPart{
+			labelName: "target_label",
+			values:    []string{"one", "two"},
+		},
+	})
+
+	expectation := client.Selector("rate(my_series{target_label=~\"one|two\"}[2m])")
+	require.Equal(t, selector, expectation)
+}
+
+func TestQueryWithGroupBy(t *testing.T) {
+	builder, _ := NewQueryBuilder("sum(rate(<<.Series>>{<<.LabelMatchers>>}[2m])) by (<<.GroupBy>>)")
+
+	selector, _ := builder.BuildSelector("my_series", "my_grouping", []string{}, []queryPart{
+		queryPart{
+			labelName: "target_label",
+			values:    []string{"one", "two"},
+		},
+	})
+
+	expectation := client.Selector("sum(rate(my_series{target_label=~\"one|two\"}[2m])) by (my_grouping)")
+	require.Equal(t, selector, expectation)
+}
+
+//TODO: Ensure that the LabelValuesByName and GroupBySlice placeholders function correctly.

pkg/custom-provider/regex_matcher.go

@@ -0,0 +1,47 @@
+package provider
+
+import (
+	"fmt"
+	"regexp"
+
+	"github.com/directxman12/k8s-prometheus-adapter/pkg/config"
+)
+
+// reMatcher either positively or negatively matches a regex
+type reMatcher struct {
+	regex    *regexp.Regexp
+	positive bool
+}
+
+func newReMatcher(cfg config.RegexFilter) (*reMatcher, error) {
+	if cfg.Is != "" && cfg.IsNot != "" {
+		return nil, fmt.Errorf("cannot have both an `is` (%q) and `isNot` (%q) expression in a single filter", cfg.Is, cfg.IsNot)
+	}
+	if cfg.Is == "" && cfg.IsNot == "" {
+		return nil, fmt.Errorf("must have either an `is` or `isNot` expression in a filter")
+	}
+
+	var positive bool
+	var regexRaw string
+	if cfg.Is != "" {
+		positive = true
+		regexRaw = cfg.Is
+	} else {
+		positive = false
+		regexRaw = cfg.IsNot
+	}
+
+	regex, err := regexp.Compile(regexRaw)
+	if err != nil {
+		return nil, fmt.Errorf("unable to compile series filter %q: %v", regexRaw, err)
+	}
+
+	return &reMatcher{
+		regex:    regex,
+		positive: positive,
+	}, nil
+}
+
+func (m *reMatcher) Matches(val string) bool {
+	return m.regex.MatchString(val) == m.positive
+}

pkg/custom-provider/resource_converter.go

@@ -0,0 +1,192 @@
+package provider
+
+import (
+	"bytes"
+	"fmt"
+	"strings"
+	"sync"
+	"text/template"
+
+	apimeta "k8s.io/apimachinery/pkg/api/meta"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+
+	prom "github.com/directxman12/k8s-prometheus-adapter/pkg/client"
+	"github.com/directxman12/k8s-prometheus-adapter/pkg/config"
+	"github.com/golang/glog"
+	"github.com/kubernetes-incubator/custom-metrics-apiserver/pkg/provider"
+	pmodel "github.com/prometheus/common/model"
+)
+
+type ResourceConverter interface {
+	// ResourcesForSeries returns the group-resources associated with the given series,
+	// as well as whether or not the given series has the "namespace" resource).
+	ResourcesForSeries(series prom.Series) (res []schema.GroupResource, namespaced bool)
+	// LabelForResource returns the appropriate label for the given resource.
+	LabelForResource(resource schema.GroupResource) (pmodel.LabelName, error)
+}
+
+type resourceConverter struct {
+	labelResourceMu   sync.RWMutex
+	labelToResource   map[pmodel.LabelName]schema.GroupResource
+	resourceToLabel   map[schema.GroupResource]pmodel.LabelName
+	labelResExtractor *labelGroupResExtractor
+	mapper            apimeta.RESTMapper
+	labelTemplate     *template.Template
+}
+
+func NewResourceConverter(resourceTemplate string, overrides map[string]config.GroupResource, mapper apimeta.RESTMapper) (ResourceConverter, error) {
+	converter := &resourceConverter{
+		labelToResource: make(map[pmodel.LabelName]schema.GroupResource),
+		resourceToLabel: make(map[schema.GroupResource]pmodel.LabelName),
+		mapper:          mapper,
+	}
+
+	if resourceTemplate != "" {
+		labelTemplate, err := template.New("resource-label").Delims("<<", ">>").Parse(resourceTemplate)
+		if err != nil {
+			return converter, fmt.Errorf("unable to parse label template %q: %v", resourceTemplate, err)
+		}
+		converter.labelTemplate = labelTemplate
+
+		labelResExtractor, err := newLabelGroupResExtractor(labelTemplate)
+		if err != nil {
+			return converter, fmt.Errorf("unable to generate label format from template %q: %v", resourceTemplate, err)
+		}
+		converter.labelResExtractor = labelResExtractor
+	}
+
+	// invert the structure for consistency with the template
+	for lbl, groupRes := range overrides {
+		infoRaw := provider.CustomMetricInfo{
+			GroupResource: schema.GroupResource{
+				Group:    groupRes.Group,
+				Resource: groupRes.Resource,
+			},
+		}
+		info, _, err := infoRaw.Normalized(converter.mapper)
+		if err != nil {
+			return nil, fmt.Errorf("unable to normalize group-resource %v: %v", groupRes, err)
+		}
+
+		converter.labelToResource[pmodel.LabelName(lbl)] = info.GroupResource
+		converter.resourceToLabel[info.GroupResource] = pmodel.LabelName(lbl)
+	}
+
+	return converter, nil
+}
+
+func (n *resourceConverter) LabelForResource(resource schema.GroupResource) (pmodel.LabelName, error) {
+	n.labelResourceMu.RLock()
+	// check if we have a cached copy or override
+	lbl, ok := n.resourceToLabel[resource]
+	n.labelResourceMu.RUnlock() // release before we call makeLabelForResource
+	if ok {
+		return lbl, nil
+	}
+
+	// NB: we don't actually care about the gap between releasing read lock
+	// and acquiring the write lock -- if we do duplicate work sometimes, so be
+	// it, as long as we're correct.
+
+	// otherwise, use the template and save the result
+	lbl, err := n.makeLabelForResource(resource)
+	if err != nil {
+		return "", fmt.Errorf("unable to convert resource %s into label: %v", resource.String(), err)
+	}
+	return lbl, nil
+}
+
+var groupNameSanitizer = strings.NewReplacer(".", "_", "-", "_")
+
+// makeLabelForResource constructs a label name for the given resource, and saves the result.
+// It must *not* be called under an existing lock.
+func (n *resourceConverter) makeLabelForResource(resource schema.GroupResource) (pmodel.LabelName, error) {
+	if n.labelTemplate == nil {
+		return "", fmt.Errorf("no generic resource label form specified for this metric")
+	}
+	buff := new(bytes.Buffer)
+
+	singularRes, err := n.mapper.ResourceSingularizer(resource.Resource)
+	if err != nil {
+		return "", fmt.Errorf("unable to singularize resource %s: %v", resource.String(), err)
+	}
+	convResource := schema.GroupResource{
+		Group:    groupNameSanitizer.Replace(resource.Group),
+		Resource: singularRes,
+	}
+
+	if err := n.labelTemplate.Execute(buff, convResource); err != nil {
+		return "", err
+	}
+	if buff.Len() == 0 {
+		return "", fmt.Errorf("empty label produced by label template")
+	}
+	lbl := pmodel.LabelName(buff.String())
+
+	n.labelResourceMu.Lock()
+	defer n.labelResourceMu.Unlock()
+
+	n.resourceToLabel[resource] = lbl
+	n.labelToResource[lbl] = resource
+	return lbl, nil
+}
+
+func (n *resourceConverter) ResourcesForSeries(series prom.Series) ([]schema.GroupResource, bool) {
+	// use an updates map to avoid having to drop the read lock to update the cache
+	// until the end.  Since we'll probably have few updates after the first run,
+	// this should mean that we rarely have to hold the write lock.
+	var resources []schema.GroupResource
+	updates := make(map[pmodel.LabelName]schema.GroupResource)
+	namespaced := false
+
+	// use an anon func to get the right defer behavior
+	func() {
+		n.labelResourceMu.RLock()
+		defer n.labelResourceMu.RUnlock()
+
+		for lbl := range series.Labels {
+			var groupRes schema.GroupResource
+			var ok bool
+
+			// check if we have an override
+			if groupRes, ok = n.labelToResource[lbl]; ok {
+				resources = append(resources, groupRes)
+			} else if groupRes, ok = updates[lbl]; ok {
+				resources = append(resources, groupRes)
+			} else if n.labelResExtractor != nil {
+				// if not, check if it matches the form we expect, and if so,
+				// convert to a group-resource.
+				if groupRes, ok = n.labelResExtractor.GroupResourceForLabel(lbl); ok {
+					info, _, err := provider.CustomMetricInfo{GroupResource: groupRes}.Normalized(n.mapper)
+					if err != nil {
+						glog.Errorf("unable to normalize group-resource %s from label %q, skipping: %v", groupRes.String(), lbl, err)
+						continue
+					}
+
+					groupRes = info.GroupResource
+					resources = append(resources, groupRes)
+					updates[lbl] = groupRes
+				}
+			}
+
+			if groupRes == nsGroupResource {
+				namespaced = true
+			}
+		}
+	}()
+
+	// update the cache for next time.  This should only be called by discovery,
+	// so we don't really have to worry about the gap between read and write locks
+	// (plus, we don't care if someone else updates the cache first, since the results
+	// are necessarily the same, so at most we've done extra work).
+	if len(updates) > 0 {
+		n.labelResourceMu.Lock()
+		defer n.labelResourceMu.Unlock()
+
+		for lbl, groupRes := range updates {
+			n.labelToResource[lbl] = groupRes
+		}
+	}
+
+	return resources, namespaced
+}

pkg/custom-provider/series_filterer.go

@@ -0,0 +1,61 @@
+package provider
+
+import (
+	"fmt"
+
+	prom "github.com/directxman12/k8s-prometheus-adapter/pkg/client"
+	"github.com/directxman12/k8s-prometheus-adapter/pkg/config"
+)
+
+type SeriesFilterer interface {
+	FilterSeries(series []prom.Series) []prom.Series
+	AddRequirement(filter config.RegexFilter) error
+}
+
+type seriesFilterer struct {
+	seriesMatchers []*reMatcher
+}
+
+func NewSeriesFilterer(filters []config.RegexFilter) (SeriesFilterer, error) {
+	seriesMatchers := make([]*reMatcher, len(filters))
+	for i, filterRaw := range filters {
+		matcher, err := newReMatcher(filterRaw)
+		if err != nil {
+			return nil, fmt.Errorf("unable to generate series name filter: %v", err)
+		}
+		seriesMatchers[i] = matcher
+	}
+
+	return &seriesFilterer{
+		seriesMatchers: seriesMatchers,
+	}, nil
+}
+
+func (n *seriesFilterer) AddRequirement(filterRaw config.RegexFilter) error {
+	matcher, err := newReMatcher(filterRaw)
+	if err != nil {
+		return fmt.Errorf("unable to generate series name filter: %v", err)
+	}
+
+	n.seriesMatchers = append(n.seriesMatchers, matcher)
+	return nil
+}
+
+func (n *seriesFilterer) FilterSeries(initialSeries []prom.Series) []prom.Series {
+	if len(n.seriesMatchers) == 0 {
+		return initialSeries
+	}
+
+	finalSeries := make([]prom.Series, 0, len(initialSeries))
+SeriesLoop:
+	for _, series := range initialSeries {
+		for _, matcher := range n.seriesMatchers {
+			if !matcher.Matches(series.Name) {
+				continue SeriesLoop
+			}
+		}
+		finalSeries = append(finalSeries, series)
+	}
+
+	return finalSeries
+}

pkg/custom-provider/series_filterer_test.go

@@ -0,0 +1,114 @@
+package provider
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	prom "github.com/directxman12/k8s-prometheus-adapter/pkg/client"
+	"github.com/directxman12/k8s-prometheus-adapter/pkg/config"
+)
+
+func TestPositiveFilter(t *testing.T) {
+	filters := []config.RegexFilter{
+		config.RegexFilter{
+			Is: "one_of_(yes|positive|ok)",
+		},
+	}
+
+	series := []string{"one_of_yes", "one_of_no"}
+	expectedSeries := []string{"one_of_yes"}
+
+	RunSeriesFiltererTest(t, filters, series, expectedSeries)
+}
+
+func TestNegativeFilter(t *testing.T) {
+	filters := []config.RegexFilter{
+		config.RegexFilter{
+			IsNot: "one_of_(yes|positive|ok)",
+		},
+	}
+
+	series := []string{"one_of_yes", "one_of_no"}
+	expectedSeries := []string{"one_of_no"}
+
+	RunSeriesFiltererTest(t, filters, series, expectedSeries)
+}
+
+func TestPositiveAndNegativeFilterError(t *testing.T) {
+	filters := []config.RegexFilter{
+		config.RegexFilter{
+			Is:    "series_\\d+",
+			IsNot: "series_[2-3]+",
+		},
+	}
+
+	_, err := NewSeriesFilterer(filters)
+	require.Error(t, err)
+}
+
+func TestAddRequirementAppliesFilter(t *testing.T) {
+	seriesNames := []string{"series_1", "series_2", "series_3"}
+	series := BuildSeriesFromNames(seriesNames)
+
+	filters := []config.RegexFilter{
+		config.RegexFilter{
+			Is: "series_\\d+",
+		},
+	}
+
+	filterer, err := NewSeriesFilterer(filters)
+	require.NoError(t, err)
+
+	//Test it once with the default filters.
+	result := filterer.FilterSeries(series)
+	expectedSeries := []string{"series_1", "series_2", "series_3"}
+	VerifyMatches(t, result, expectedSeries)
+
+	//Add a new filter and test again.
+	filterer.AddRequirement(config.RegexFilter{
+		Is: "series_[2-3]",
+	})
+	result = filterer.FilterSeries(series)
+	expectedSeries = []string{"series_2", "series_3"}
+	VerifyMatches(t, result, expectedSeries)
+}
+
+func RunSeriesFiltererTest(t *testing.T, filters []config.RegexFilter, seriesNames []string, expectedResults []string) {
+	series := BuildSeriesFromNames(seriesNames)
+
+	filterer, err := NewSeriesFilterer(filters)
+	require.NoError(t, err)
+
+	matches := filterer.FilterSeries(series)
+
+	VerifyMatches(t, matches, expectedResults)
+}
+
+func VerifyMatches(t *testing.T, series []prom.Series, expectedResults []string) {
+	require.Equal(t, len(series), len(expectedResults))
+
+	existingSeries := make(map[string]bool)
+
+	for _, series := range series {
+		existingSeries[series.Name] = true
+	}
+
+	for _, expectedResult := range expectedResults {
+		_, exists := existingSeries[expectedResult]
+
+		require.True(t, exists)
+	}
+}
+
+func BuildSeriesFromNames(seriesNames []string) []prom.Series {
+	series := make([]prom.Series, len(seriesNames))
+
+	for i, name := range seriesNames {
+		series[i] = prom.Series{
+			Name: name,
+		}
+	}
+
+	return series
+}

pkg/custom-provider/series_registry.go

@@ -88,7 +88,7 @@ func NewBasicSeriesRegistry(lister MetricListerWithNotification, mapper apimeta.
 	return &registry
 }
 
-func (r basicSeriesRegistry) onNewDataAvailable(result metricUpdateResult) {
+func (r *basicSeriesRegistry) onNewDataAvailable(result metricUpdateResult) {
 	newSeriesSlices := result.series
 	namers := result.namers
 
@@ -100,13 +100,18 @@ func (r basicSeriesRegistry) onNewDataAvailable(result metricUpdateResult) {
 	for i, newSeries := range newSeriesSlices {
 		namer := namers[i]
 		for _, series := range newSeries {
-			// TODO: warn if it doesn't match any resources
-			resources, namespaced := namer.ResourcesForSeries(series)
-			name, err := namer.MetricNameForSeries(series)
+			identity, err := namer.IdentifySeries(series)
+
 			if err != nil {
 				glog.Errorf("unable to name series %q, skipping: %v", series.String(), err)
 				continue
 			}
+
+			// TODO: warn if it doesn't match any resources
+			resources := identity.resources
+			namespaced := identity.namespaced
+			name := identity.name
+
 			for _, resource := range resources {
 				info := provider.CustomMetricInfo{
 					GroupResource: resource,
@@ -181,24 +186,25 @@ func (r *basicSeriesRegistry) QueryForMetric(metricInfo provider.CustomMetricInf
 func (r *basicSeriesRegistry) QueryForExternalMetric(metricInfo provider.ExternalMetricInfo, metricSelector labels.Selector) (query prom.Selector, found bool) {
 	r.mu.RLock()
 	defer r.mu.RUnlock()
+	//TODO: Implementation
+	return "", false
+	// info, infoFound := r.info[metricInfo]
+	// if !infoFound {
+	// 	//TODO: Weird that it switches between types here.
+	// 	glog.V(10).Infof("metric %v not registered", metricInfo)
+	// 	return "", false
+	// }
 
-	info, infoFound := r.info[metricInfo]
-	if !infoFound {
-		//TODO: Weird that it switches between types here.
-		glog.V(10).Infof("metric %v not registered", metricInfo)
-		return "", false
-	}
+	// query, err := info.namer.QueryForExternalSeries(info.seriesName, metricSelector)
+	// if err != nil {
+	// 	//TODO: See what was being .String() and implement that for ExternalMetricInfo.
+	// 	// errorVal := metricInfo.String()
+	// 	errorVal := "something"
+	// 	glog.Errorf("unable to construct query for metric %s: %v", errorVal, err)
+	// 	return "", false
+	// }
 
-	query, err := info.namer.QueryForExternalSeries(info.seriesName, metricSelector)
-	if err != nil {
-		//TODO: See what was being .String() and implement that for ExternalMetricInfo.
-		// errorVal := metricInfo.String()
-		errorVal := "something"
-		glog.Errorf("unable to construct query for metric %s: %v", errorVal, err)
-		return "", false
-	}
-
-	return query, true
+	// return query, true
 }
 
 func (r *basicSeriesRegistry) MatchValuesToNames(metricInfo provider.CustomMetricInfo, values pmodel.Vector) (matchedValues map[string]pmodel.SampleValue, found bool) {
@@ -216,7 +222,7 @@ func (r *basicSeriesRegistry) MatchValuesToNames(metricInfo provider.CustomMetri
 		return nil, false
 	}
 
-	resourceLbl, err := info.namer.LabelForResource(metricInfo.GroupResource)
+	resourceLbl, err := info.namer.ResourceConverter().LabelForResource(metricInfo.GroupResource)
 	if err != nil {
 		glog.Errorf("unable to construct resource label for metric %s: %v", metricInfo.String(), err)
 		return nil, false

pkg/custom-provider/series_registry_test.go

@@ -117,17 +117,60 @@ var seriesRegistryTestSeries = [][]prom.Series{
 	},
 }
 
+type myType struct {
+	a int
+	b string
+	m map[string]int
+}
+
+type mapWrapper struct {
+	item map[string]int
+}
+
+func (o *myType) Mutate(newMap mapWrapper) {
+	o.a = 2
+	o.b = "two"
+	o.m = newMap.item
+}
+
+func TestWeirdStuff(t *testing.T) {
+	o := myType{
+		a: 1,
+		b: "one",
+		m: map[string]int{
+			"one": 1,
+		},
+	}
+
+	oldMap := o.m
+	newMap := map[string]int{
+		"two": 2,
+	}
+	newWrapper := mapWrapper{
+		item: newMap,
+	}
+	oldWrapper := mapWrapper{
+		item: oldMap,
+	}
+	o.Mutate(newWrapper)
+	o.Mutate(oldWrapper)
+}
+
 func TestSeriesRegistry(t *testing.T) {
 	assert := assert.New(t)
-	require := require.New(t)
 
 	namers := setupMetricNamer(t)
 	registry := &basicSeriesRegistry{
 		mapper: restMapper(),
 	}
 
+	updateResult := metricUpdateResult{
+		series: seriesRegistryTestSeries,
+		namers: namers,
+	}
+
 	// set up the registry
-	require.NoError(registry.SetSeries(seriesRegistryTestSeries, namers))
+	registry.onNewDataAvailable(updateResult)
 
 	// make sure each metric got registered and can form queries
 	testCases := []struct {
@@ -285,7 +328,11 @@ func BenchmarkSetSeries(b *testing.B) {
 
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		registry.SetSeries(newSeriesSlices, namers)
+		updateResult := metricUpdateResult{
+			series: newSeriesSlices,
+			namers: namers,
+		}
+		registry.onNewDataAvailable(updateResult)
 	}
 }