feat(analytics): allow to set Authorization header for prometheus (#3656

)

config/flipt.schema.cue

@@ -430,6 +430,7 @@ import "strings"
 			prometheus?: {
 				enabled?: bool | *false
 				url?:     string | *""
+				headers?: [string]: string
 			}
 		}
 		buffer?: {

config/flipt.schema.json

@@ -1465,6 +1465,10 @@
                 "url": {
                   "type": "string",
                   "default": ""
+                },
+                "headers": {
+                  "type": ["object", "null"],
+                  "additionalProperties": { "type": "string" }
                 }
               },
               "title": "Prometheus"

examples/analytics/prometheus/docker-compose.yml

@@ -5,10 +5,16 @@ services:
     image: prom/prometheus:latest
     volumes:
       - "./prometheus.yml:/etc/prometheus/prometheus.yml"
+      - "./web-config.yml:/etc/prometheus/web-config.yml"
     ports:
       - "9090:9090"
+    command:
+      - --config.file=/etc/prometheus/prometheus.yml
+      - --web.config.file=/etc/prometheus/web-config.yml
   flipt:
     image: flipt/flipt:latest
+    volumes:
+      - "./flipt-config.yml:/etc/flipt/config/default.yml"
     depends_on:
       prometheus:
         condition: service_healthy
@@ -21,6 +27,7 @@ services:
       - FLIPT_LOG_LEVEL=info
       - FLIPT_ANALYTICS_STORAGE_PROMETHEUS_ENABLED=true
       - FLIPT_ANALYTICS_STORAGE_PROMETHEUS_URL=http://prometheus:9090
+      - PROMETHEUS_AUTH_TOKEN='Basic YWRtaW46dGVzdA=='
       - FLIPT_META_TELEMETRY_ENABLED=false
     command: ["/flipt", "--force-migrate"]
 

examples/analytics/prometheus/flipt-config.yml

@@ -0,0 +1,7 @@
+analytics:
+  storage:
+    prometheus:
+      enabled: true
+      url: http://localhost:9090
+      headers:
+        Authorization: ${PROMETHEUS_AUTH_TOKEN}

examples/analytics/prometheus/web-config.yml

@@ -0,0 +1,3 @@
+basic_auth_users:
+  admin: $2b$12$hNf2lSsxfm0.i4a.1kVpSOVyBCfIB51VRjgBUyv6kdnyTlgWj81Ay
+  # password is `test`

internal/config/analytics.go

@@ -60,8 +60,9 @@ func (c *ClickhouseConfig) Options() (*clickhouse.Options, error) {
 
 // PrometheusConfig defines the connection details for connecting Flipt to Prometheus.
 type PrometheusConfig struct {
-	Enabled bool   `json:"enabled,omitempty" mapstructure:"enabled" yaml:"enabled,omitempty"`
-	URL     string `json:"url,omitempty" mapstructure:"url" yaml:"url,omitempty"`
+	Enabled bool              `json:"enabled,omitempty" mapstructure:"enabled" yaml:"enabled,omitempty"`
+	URL     string            `json:"-" mapstructure:"url" yaml:"-"`
+	Headers map[string]string `json:"-" mapstructure:"headers" yaml:"-"`
 }
 
 //nolint:unparam

internal/server/analytics/prometheus/client.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"math"
+	"net/http"
 	"time"
 
 	"github.com/prometheus/client_golang/api"
@@ -26,6 +27,12 @@ type client struct {
 func New(logger *zap.Logger, cfg *config.Config) (*client, error) {
 	apiClient, err := api.NewClient(api.Config{
 		Address: cfg.Analytics.Storage.Prometheus.URL,
+		RoundTripper: roundTripFunc(func(r *http.Request) (*http.Response, error) {
+			for k, v := range cfg.Analytics.Storage.Prometheus.Headers {
+				r.Header.Set(k, v)
+			}
+			return api.DefaultRoundTripper.RoundTrip(r)
+		}),
 	})
 	if err != nil {
 		return nil, err
@@ -76,3 +83,9 @@ func (c *client) GetFlagEvaluationsCount(ctx context.Context, req *panalytics.Fl
 func (c *client) String() string {
 	return "prometheus"
 }
+
+type roundTripFunc func(r *http.Request) (*http.Response, error)
+
+func (f roundTripFunc) RoundTrip(r *http.Request) (*http.Response, error) {
+	return f(r)
+}