Move configs handling to separate package

Author: juliusv

ruler/configs.go renamed to configs/configs.go

@@ -1,4 +1,4 @@
-package ruler
+package configs
 
 import (
 	"encoding/json"
@@ -15,32 +15,34 @@ import (
 
 // TODO: Extract configs client logic into go client library (ala users)
 
-type configID int
+// A ConfigID is the ID of a single organization's Cortex configuration.
+type ConfigID int
 
-type cortexConfig struct {
+// A CortexConfig is a Cortex configuration for a single organization.
+type CortexConfig struct {
 	// RulesFiles maps from a rules filename to file contents.
 	RulesFiles map[string]string `json:"rules_files"`
 }
 
-// cortexConfigView is what's returned from the Weave Cloud configs service
+// CortexConfigView is what's returned from the Weave Cloud configs service
 // when we ask for all Cortex configurations.
 //
 // The configs service is essentially a JSON blob store that gives each
 // _version_ of a configuration a unique ID and guarantees that later versions
 // have greater IDs.
-type cortexConfigView struct {
-	ConfigID configID     `json:"id"`
-	Config   cortexConfig `json:"config"`
+type CortexConfigView struct {
+	ConfigID ConfigID     `json:"id"`
+	Config   CortexConfig `json:"config"`
 }
 
-// cortexConfigsResponse is a response from server for getOrgConfigs
-type cortexConfigsResponse struct {
-	// Configs maps organization ID to their latest cortexConfigView.
-	Configs map[string]cortexConfigView `json:"configs"`
+// CortexConfigsResponse is a response from server for GetOrgConfigs.
+type CortexConfigsResponse struct {
+	// Configs maps organization ID to their latest CortexConfigView.
+	Configs map[string]CortexConfigView `json:"configs"`
 }
 
-func configsFromJSON(body io.Reader) (*cortexConfigsResponse, error) {
-	var configs cortexConfigsResponse
+func configsFromJSON(body io.Reader) (*CortexConfigsResponse, error) {
+	var configs CortexConfigsResponse
 	if err := json.NewDecoder(body).Decode(&configs); err != nil {
 		log.Errorf("configs: couldn't decode JSON body: %v", err)
 		return nil, err
@@ -49,9 +51,9 @@ func configsFromJSON(body io.Reader) (*cortexConfigsResponse, error) {
 	return &configs, nil
 }
 
-// getLatestConfigID returns the last config ID from a set of configs.
-func (c cortexConfigsResponse) getLatestConfigID() configID {
-	latest := configID(0)
+// GetLatestConfigID returns the last config ID from a set of configs.
+func (c CortexConfigsResponse) GetLatestConfigID() ConfigID {
+	latest := ConfigID(0)
 	for _, config := range c.Configs {
 		if config.ConfigID > latest {
 			latest = config.ConfigID
@@ -60,10 +62,10 @@ func (c cortexConfigsResponse) getLatestConfigID() configID {
 	return latest
 }
 
-// Get the rules from the cortex configuration.
+// GetRules gets the rules from the Cortex configuration.
 //
 // Strongly inspired by `loadGroups` in Prometheus.
-func (c cortexConfig) GetRules() ([]rules.Rule, error) {
+func (c CortexConfig) GetRules() ([]rules.Rule, error) {
 	result := []rules.Rule{}
 	for fn, content := range c.RulesFiles {
 		stmts, err := promql.ParseStmts(content)
@@ -90,24 +92,25 @@ func (c cortexConfig) GetRules() ([]rules.Rule, error) {
 	return result, nil
 }
 
-type configsAPI struct {
-	url     *url.URL
-	timeout time.Duration
+// API allows retrieving Cortex configs.
+type API struct {
+	URL     *url.URL
+	Timeout time.Duration
 }
 
-// getOrgConfigs returns all Cortex configurations from a configs api server
-// that have been updated after the given configID was last updated.
-func (c *configsAPI) getOrgConfigs(since configID) (*cortexConfigsResponse, error) {
+// GetOrgConfigs returns all Cortex configurations from a configs API server
+// that have been updated after the given ConfigID was last updated.
+func (c *API) GetOrgConfigs(since ConfigID) (*CortexConfigsResponse, error) {
 	suffix := ""
 	if since != 0 {
 		suffix = fmt.Sprintf("?since=%d", since)
 	}
-	url := fmt.Sprintf("%s/private/api/configs/org/cortex%s", c.url.String(), suffix)
+	url := fmt.Sprintf("%s/private/api/configs/org/cortex%s", c.URL.String(), suffix)
 	req, err := http.NewRequest("GET", url, nil)
 	if err != nil {
 		return nil, err
 	}
-	client := &http.Client{Timeout: c.timeout}
+	client := &http.Client{Timeout: c.Timeout}
 	res, err := client.Do(req)
 	if err != nil {
 		return nil, err

ruler/configs_test.go renamed to configs/configs_test.go

@@ -1,4 +1,4 @@
-package ruler
+package configs
 
 import (
 	"strings"
@@ -23,10 +23,10 @@ func TestJSONDecoding(t *testing.T) {
 }
 `))
 	assert.Nil(t, err)
-	expected := cortexConfigsResponse{Configs: map[string]cortexConfigView{
+	expected := CortexConfigsResponse{Configs: map[string]CortexConfigView{
 		"2": {
 			ConfigID: 1,
-			Config: cortexConfig{
+			Config: CortexConfig{
 				RulesFiles: map[string]string{
 					"recording.rules": ":scope_authfe_request_duration_seconds:99quantile = histogram_quantile(0.99, sum(rate(scope_request_duration_seconds_bucket{ws=\"false\",job=\"authfe\",route!~\"(admin|metrics).*\"}[5m])) by (le))\n",
 				},

ruler/ruler.go

@@ -17,6 +17,7 @@ import (
 
 	"github.com/weaveworks/common/user"
 	"github.com/weaveworks/cortex/chunk"
+	"github.com/weaveworks/cortex/configs"
 	"github.com/weaveworks/cortex/distributor"
 	"github.com/weaveworks/cortex/querier"
 	"github.com/weaveworks/cortex/util"
@@ -201,7 +202,10 @@ type Server struct {
 
 // NewServer makes a new rule processing server.
 func NewServer(cfg Config, ruler *Ruler) (*Server, error) {
-	c := configsAPI{cfg.ConfigsAPIURL.URL, cfg.ClientTimeout}
+	c := configs.API{
+		URL:     cfg.ConfigsAPIURL.URL,
+		Timeout: cfg.ClientTimeout,
+	}
 	// TODO: Separate configuration for polling interval.
 	s := newScheduler(c, cfg.EvaluationInterval, cfg.EvaluationInterval)
 	if cfg.NumWorkers <= 0 {

ruler/scheduler.go

@@ -12,6 +12,7 @@ import (
 	"github.com/prometheus/prometheus/rules"
 
 	"github.com/weaveworks/common/instrument"
+	"github.com/weaveworks/cortex/configs"
 )
 
 const (
@@ -61,30 +62,30 @@ func (w workItem) Defer(interval time.Duration) workItem {
 }
 
 type scheduler struct {
-	configsAPI         configsAPI // XXX: Maybe make this an interface ConfigSource or similar.
+	configsAPI         configs.API // XXX: Maybe make this an interface ConfigSource or similar.
 	evaluationInterval time.Duration
 	q                  *SchedulingQueue
 
 	// All the configurations that we have. Only used for instrumentation.
-	cfgs map[string]cortexConfig
+	cfgs map[string]configs.CortexConfig
 
 	pollInterval time.Duration
 
-	latestConfig configID
+	latestConfig configs.ConfigID
 	latestMutex  sync.RWMutex
 
 	stop chan struct{}
 	done chan struct{}
 }
 
 // newScheduler makes a new scheduler.
-func newScheduler(configsAPI configsAPI, evaluationInterval, pollInterval time.Duration) scheduler {
+func newScheduler(configsAPI configs.API, evaluationInterval, pollInterval time.Duration) scheduler {
 	return scheduler{
 		configsAPI:         configsAPI,
 		evaluationInterval: evaluationInterval,
 		pollInterval:       pollInterval,
 		q:                  NewSchedulingQueue(clockwork.NewRealClock()),
-		cfgs:               map[string]cortexConfig{},
+		cfgs:               map[string]configs.CortexConfig{},
 
 		stop: make(chan struct{}),
 		done: make(chan struct{}),
@@ -121,7 +122,7 @@ func (s *scheduler) Stop() {
 
 // Load the full set of configurations from the server, retrying with backoff
 // until we can get them.
-func (s *scheduler) loadAllConfigs() map[string]cortexConfigView {
+func (s *scheduler) loadAllConfigs() map[string]configs.CortexConfigView {
 	backoff := minBackoff
 	for {
 		cfgs, err := s.poll()
@@ -148,25 +149,25 @@ func (s *scheduler) updateConfigs(now time.Time) error {
 }
 
 // poll the configuration server. Not re-entrant.
-func (s *scheduler) poll() (map[string]cortexConfigView, error) {
+func (s *scheduler) poll() (map[string]configs.CortexConfigView, error) {
 	configID := s.latestConfig
-	var cfgs *cortexConfigsResponse
+	var cfgs *configs.CortexConfigsResponse
 	err := instrument.TimeRequestHistogram(context.Background(), "Configs.GetOrgConfigs", configsRequestDuration, func(_ context.Context) error {
 		var err error
-		cfgs, err = s.configsAPI.getOrgConfigs(configID)
+		cfgs, err = s.configsAPI.GetOrgConfigs(configID)
 		return err
 	})
 	if err != nil {
 		log.Warnf("Scheduler: configs server poll failed: %v", err)
 		return nil, err
 	}
 	s.latestMutex.Lock()
-	s.latestConfig = cfgs.getLatestConfigID()
+	s.latestConfig = cfgs.GetLatestConfigID()
 	s.latestMutex.Unlock()
 	return cfgs.Configs, nil
 }
 
-func (s *scheduler) addNewConfigs(now time.Time, cfgs map[string]cortexConfigView) {
+func (s *scheduler) addNewConfigs(now time.Time, cfgs map[string]configs.CortexConfigView) {
 	// TODO: instrument how many configs we have, both valid & invalid.
 	log.Debugf("Adding %d configurations", len(cfgs))
 	for userID, config := range cfgs {