[refactor] Move sampling http handler to internal/sampling/http (#6545)

## Which problem is this PR solving?
- Towards #6411

## Description of the changes
- Move sampling http handler from pkg/clientcfg/clientcfghttp to
internal/sampling/http

## How was this change tested?
- Covered by existing

## Checklist
- [x] I have read
https://github.com/jaegertracing/jaeger/blob/master/CONTRIBUTING_GUIDELINES.md
- [x] I have signed all commits
- [ ] I have added unit tests for the new functionality
- [x] I have run lint and test steps successfully
  - for `jaeger`: `make lint test`
  - for `jaeger-ui`: `npm run lint` and `npm run test`

Signed-off-by: Aryan Goyal <[email protected]>

cmd/agent/app/httpserver/srv.go

@@ -13,14 +13,14 @@ import (
 	"go.uber.org/zap/zapcore"
 
 	"github.com/jaegertracing/jaeger/cmd/agent/app/configmanager"
-	"github.com/jaegertracing/jaeger/pkg/clientcfg/clientcfghttp"
+	samplinghttp "github.com/jaegertracing/jaeger/internal/sampling/http"
 	"github.com/jaegertracing/jaeger/pkg/metrics"
 )
 
 // NewHTTPServer creates a new server that hosts an HTTP/JSON endpoint for clients
 // to query for sampling strategies.
 func NewHTTPServer(hostPort string, manager configmanager.ClientConfigManager, mFactory metrics.Factory, logger *zap.Logger) *http.Server {
-	handler := clientcfghttp.NewHTTPHandler(clientcfghttp.HTTPHandlerParams{
+	handler := samplinghttp.NewHandler(samplinghttp.HandlerParams{
 		ConfigManager:          manager,
 		MetricsFactory:         mFactory,
 		LegacySamplingEndpoint: true,

cmd/collector/app/server/http.go

@@ -15,7 +15,7 @@ import (
 
 	"github.com/jaegertracing/jaeger/cmd/collector/app/handler"
 	"github.com/jaegertracing/jaeger/cmd/collector/app/sampling/samplingstrategy"
-	clientcfgHandler "github.com/jaegertracing/jaeger/pkg/clientcfg/clientcfghttp"
+	samplinghttp "github.com/jaegertracing/jaeger/internal/sampling/http"
 	"github.com/jaegertracing/jaeger/pkg/healthcheck"
 	"github.com/jaegertracing/jaeger/pkg/httpmetrics"
 	"github.com/jaegertracing/jaeger/pkg/metrics"
@@ -59,8 +59,8 @@ func serveHTTP(server *http.Server, listener net.Listener, params *HTTPServerPar
 	apiHandler := handler.NewAPIHandler(params.Handler)
 	apiHandler.RegisterRoutes(r)
 
-	cfgHandler := clientcfgHandler.NewHTTPHandler(clientcfgHandler.HTTPHandlerParams{
-		ConfigManager: &clientcfgHandler.ConfigManager{
+	cfgHandler := samplinghttp.NewHandler(samplinghttp.HandlerParams{
+		ConfigManager: &samplinghttp.ConfigManager{
 			SamplingProvider: params.SamplingProvider,
 		},
 		MetricsFactory:         params.MetricsFactory,

cmd/jaeger/internal/extension/remotesampling/extension.go

@@ -23,7 +23,7 @@ import (
 	"github.com/jaegertracing/jaeger/cmd/jaeger/internal/extension/jaegerstorage"
 	"github.com/jaegertracing/jaeger/internal/metrics/otelmetrics"
 	samplinggrpc "github.com/jaegertracing/jaeger/internal/sampling/grpc"
-	"github.com/jaegertracing/jaeger/pkg/clientcfg/clientcfghttp"
+	samplinghttp "github.com/jaegertracing/jaeger/internal/sampling/http"
 	"github.com/jaegertracing/jaeger/pkg/metrics"
 	"github.com/jaegertracing/jaeger/plugin/sampling/leaderelection"
 	"github.com/jaegertracing/jaeger/plugin/sampling/strategyprovider/adaptive"
@@ -229,8 +229,8 @@ func (ext *rsExtension) startAdaptiveStrategyProvider(host component.Host) error
 func (ext *rsExtension) startHTTPServer(ctx context.Context, host component.Host) error {
 	mf := otelmetrics.NewFactory(ext.telemetry.MeterProvider)
 	mf = mf.Namespace(metrics.NSOptions{Name: "jaeger_remote_sampling"})
-	handler := clientcfghttp.NewHTTPHandler(clientcfghttp.HTTPHandlerParams{
-		ConfigManager: &clientcfghttp.ConfigManager{
+	handler := samplinghttp.NewHandler(samplinghttp.HandlerParams{
+		ConfigManager: &samplinghttp.ConfigManager{
 			SamplingProvider: ext.strategyProvider,
 		},
 		MetricsFactory: mf,

pkg/clientcfg/clientcfghttp/cfgmgr.go → internal/sampling/http/cfgmgr.go

@@ -1,7 +1,7 @@
 // Copyright (c) 2020 The Jaeger Authors.
 // SPDX-License-Identifier: Apache-2.0
 
-package clientcfghttp
+package http
 
 import (
 	"context"

pkg/clientcfg/clientcfghttp/cfgmgr_test.go → internal/sampling/http/cfgmgr_test.go

@@ -1,7 +1,7 @@
 // Copyright (c) 2020 The Jaeger Authors.
 // SPDX-License-Identifier: Apache-2.0
 
-package clientcfghttp
+package http
 
 import (
 	"context"

pkg/clientcfg/clientcfghttp/handler.go → internal/sampling/http/handler.go

@@ -2,7 +2,7 @@
 // Copyright (c) 2017 Uber Technologies, Inc.
 // SPDX-License-Identifier: Apache-2.0
 
-package clientcfghttp
+package http
 
 import (
 	"encoding/json"
@@ -24,8 +24,8 @@ const mimeTypeApplicationJSON = "application/json"
 
 var errBadRequest = errors.New("bad request")
 
-// HTTPHandlerParams contains parameters that must be passed to NewHTTPHandler.
-type HTTPHandlerParams struct {
+// HandlerParams contains parameters that must be passed to NewHTTPHandler.
+type HandlerParams struct {
 	ConfigManager  configmanager.ClientConfigManager // required
 	MetricsFactory metrics.Factory                   // required
 
@@ -37,10 +37,10 @@ type HTTPHandlerParams struct {
 	LegacySamplingEndpoint bool
 }
 
-// HTTPHandler implements endpoints for used by Jaeger clients to retrieve client configuration,
+// Handler implements endpoints for used by Jaeger clients to retrieve client configuration,
 // such as sampling strategies.
-type HTTPHandler struct {
-	params  HTTPHandlerParams
+type Handler struct {
+	params  HandlerParams
 	metrics struct {
 		// Number of good sampling requests
 		SamplingRequestSuccess metrics.Counter `metric:"http-server.requests" tags:"type=sampling"`
@@ -65,15 +65,15 @@ type HTTPHandler struct {
 	}
 }
 
-// NewHTTPHandler creates new HTTPHandler.
-func NewHTTPHandler(params HTTPHandlerParams) *HTTPHandler {
-	handler := &HTTPHandler{params: params}
+// NewHandler creates new HTTPHandler.
+func NewHandler(params HandlerParams) *Handler {
+	handler := &Handler{params: params}
 	metrics.MustInit(&handler.metrics, params.MetricsFactory, nil)
 	return handler
 }
 
 // RegisterRoutes registers configuration handlers with Gorilla Router.
-func (h *HTTPHandler) RegisterRoutes(router *mux.Router) {
+func (h *Handler) RegisterRoutes(router *mux.Router) {
 	prefix := h.params.BasePath
 	if h.params.LegacySamplingEndpoint {
 		router.HandleFunc(
@@ -92,7 +92,7 @@ func (h *HTTPHandler) RegisterRoutes(router *mux.Router) {
 }
 
 // RegisterRoutes registers configuration handlers with HTTP Router.
-func (h *HTTPHandler) RegisterRoutesWithHTTP(router *http.ServeMux) {
+func (h *Handler) RegisterRoutesWithHTTP(router *http.ServeMux) {
 	prefix := h.params.BasePath
 	router.HandleFunc(
 		prefix+"/",
@@ -102,7 +102,7 @@ func (h *HTTPHandler) RegisterRoutesWithHTTP(router *http.ServeMux) {
 	)
 }
 
-func (h *HTTPHandler) serviceFromRequest(w http.ResponseWriter, r *http.Request) (string, error) {
+func (h *Handler) serviceFromRequest(w http.ResponseWriter, r *http.Request) (string, error) {
 	services := r.URL.Query()["service"]
 	if len(services) != 1 {
 		h.metrics.BadRequest.Inc(1)
@@ -112,7 +112,7 @@ func (h *HTTPHandler) serviceFromRequest(w http.ResponseWriter, r *http.Request)
 	return services[0], nil
 }
 
-func (h *HTTPHandler) writeJSON(w http.ResponseWriter, jsonData []byte) error {
+func (h *Handler) writeJSON(w http.ResponseWriter, jsonData []byte) error {
 	w.Header().Add("Content-Type", mimeTypeApplicationJSON)
 	if _, err := w.Write(jsonData); err != nil {
 		h.metrics.WriteFailures.Inc(1)
@@ -121,7 +121,7 @@ func (h *HTTPHandler) writeJSON(w http.ResponseWriter, jsonData []byte) error {
 	return nil
 }
 
-func (h *HTTPHandler) serveSamplingHTTP(
+func (h *Handler) serveSamplingHTTP(
 	w http.ResponseWriter,
 	r *http.Request,
 	encoder func(strategy *api_v2.SamplingStrategyResponse) ([]byte, error),
@@ -146,7 +146,7 @@ func (h *HTTPHandler) serveSamplingHTTP(
 	}
 }
 
-func (h *HTTPHandler) encodeThriftLegacy(strategy *api_v2.SamplingStrategyResponse) ([]byte, error) {
+func (h *Handler) encodeThriftLegacy(strategy *api_v2.SamplingStrategyResponse) ([]byte, error) {
 	tStrategy, err := t2p.ConvertSamplingResponseFromDomain(strategy)
 	if err != nil {
 		h.metrics.BadThriftFailures.Inc(1)
@@ -162,7 +162,7 @@ func (h *HTTPHandler) encodeThriftLegacy(strategy *api_v2.SamplingStrategyRespon
 	return jsonBytes, nil
 }
 
-func (h *HTTPHandler) encodeProto(strategy *api_v2.SamplingStrategyResponse) ([]byte, error) {
+func (h *Handler) encodeProto(strategy *api_v2.SamplingStrategyResponse) ([]byte, error) {
 	str, err := p2json.SamplingStrategyResponseToJSON(strategy)
 	if err != nil {
 		h.metrics.BadProtoFailures.Inc(1)
@@ -187,7 +187,7 @@ var samplingStrategyTypes = []api_v2.SamplingStrategyType{
 //
 // Thrift 0.9.3 classes generate this JSON:
 // {"strategyType":"PROBABILISTIC","probabilisticSampling":{"samplingRate":0.5}}
-func (*HTTPHandler) encodeThriftEnums092(jsonData []byte) []byte {
+func (*Handler) encodeThriftEnums092(jsonData []byte) []byte {
 	str := string(jsonData)
 	for _, strategyType := range samplingStrategyTypes {
 		str = strings.Replace(

pkg/clientcfg/clientcfghttp/handler_test.go → internal/sampling/http/handler_test.go

@@ -2,7 +2,7 @@
 // Copyright (c) 2017 Uber Technologies, Inc.
 // SPDX-License-Identifier: Apache-2.0
 
-package clientcfghttp
+package http
 
 import (
 	"encoding/json"
@@ -18,16 +18,16 @@ import (
 	"github.com/stretchr/testify/require"
 
 	"github.com/jaegertracing/jaeger/internal/metricstest"
+	tSampling092 "github.com/jaegertracing/jaeger/internal/sampling/http/thrift-0.9.2"
 	p2json "github.com/jaegertracing/jaeger/model/converter/json"
-	tSampling092 "github.com/jaegertracing/jaeger/pkg/clientcfg/clientcfghttp/thrift-0.9.2"
 	"github.com/jaegertracing/jaeger/proto-gen/api_v2"
 )
 
 type testServer struct {
 	metricsFactory   *metricstest.Factory
 	samplingProvider *mockSamplingProvider
 	server           *httptest.Server
-	handler          *HTTPHandler
+	handler          *Handler
 }
 
 func withServer(
@@ -41,7 +41,7 @@ func withServer(
 	cfgMgr := &ConfigManager{
 		SamplingProvider: samplingProvider,
 	}
-	handler := NewHTTPHandler(HTTPHandlerParams{
+	handler := NewHandler(HandlerParams{
 		ConfigManager:          cfgMgr,
 		MetricsFactory:         metricsFactory,
 		BasePath:               basePath,

pkg/clientcfg/clientcfghttp/package_test.go → internal/sampling/http/package_test.go

@@ -1,7 +1,7 @@
 // Copyright (c) 2023 The Jaeger Authors.
 // SPDX-License-Identifier: Apache-2.0
 
-package clientcfghttp
+package http
 
 import (
 	"testing"