fix thanos web route prefix register twice (#2489)

Signed-off-by: yeya24 <yb532204897@gmail.com>
Signed-off-by: Lucas Servén Marín <lserven@gmail.com>

Co-authored-by: yeya24 <yb532204897@gmail.com>

CHANGELOG.md

@@ -16,6 +16,7 @@ We use *breaking* word for marking changes that are not backward compatible (rel
 - [#2411](https://github.com/thanos-io/thanos/pull/2411) Query: fix a bug where queries might not time out sometimes due to issues with one or more StoreAPIs.
 - [#2474](https://github.com/thanos-io/thanos/pull/2474) Store: fix a panic caused by concurrent memory access during block filtering.
 - [#2472](https://github.com/thanos-io/thanos/pull/2472) Compact: fix a bug where partial blocks were never deleted, causing spam of warnings.
+- [#2484](https://github.com/thanos-io/thanos/pull/2484) Query/Ruler: fix issue #2483, when web.route-prefix is set, it is added twice in HTTP router prefix.
 
 ## [v0.12.0](https://github.com/thanos-io/thanos/releases/tag/v0.12.0) - 2020.04.15
 

cmd/thanos/query.go

@@ -8,7 +8,6 @@ import (
 	"fmt"
 	"math"
 	"net/http"
-	"path"
 	"strings"
 	"time"
 
@@ -357,7 +356,7 @@ func runQuery(
 
 		api := v1.NewAPI(logger, reg, engine, queryableCreator, enableAutodownsampling, enablePartialResponse, replicaLabels, instantDefaultMaxSourceResolution)
 
-		api.Register(router.WithPrefix(path.Join(webRoutePrefix, "/api/v1")), tracer, logger, ins)
+		api.Register(router.WithPrefix("/api/v1"), tracer, logger, ins)
 
 		srv := httpserver.New(logger, reg, comp, httpProbe,
 			httpserver.WithListen(httpBindAddr),

cmd/thanos/rule.go

@@ -8,7 +8,6 @@ import (
 	"math/rand"
 	"net/http"
 	"net/url"
-	"path"
 	"path/filepath"
 	"strconv"
 	"strings"
@@ -576,7 +575,7 @@ func runRule(
 		ui.NewRuleUI(logger, reg, ruleMgr, alertQueryURL.String(), webExternalPrefix, webPrefixHeaderName).Register(router, ins)
 
 		api := v1.NewAPI(logger, reg, ruleMgr)
-		api.Register(router.WithPrefix(path.Join(webRoutePrefix, "/api/v1")), tracer, logger, ins)
+		api.Register(router.WithPrefix("/api/v1"), tracer, logger, ins)
 
 		srv := httpserver.New(logger, reg, comp, httpProbe,
 			httpserver.WithListen(httpBindAddr),