vmalert: add disablePathAppend to remote read (#1712)

* vmalert: add disablePathAppend to remoteRead

* docs: add docs for remoteRead.disablePathAppend

app/vmalert/README.md

@@ -496,6 +496,8 @@ The shortlist of configuration flags is the following:
     	Optional bearer auth token to use for -remoteRead.url.
   -remoteRead.bearerTokenFile string
     	Optional path to bearer token file to use for -remoteRead.url.
+  -remoteRead.disablePathAppend
+    	Whether to disable automatic appending of '/api/v1/query' path to the configured -remoteRead.url.
   -remoteRead.ignoreRestoreErrors
     	Whether to ignore errors from remote storage when restoring alerts state on startup. (default true)
   -remoteRead.lookback duration

app/vmalert/datasource/vm.go

@@ -24,6 +24,7 @@ type VMStorage struct {
 	evaluationInterval time.Duration
 	extraLabels        []string
 	extraParams        []Param
+	disablePathAppend  bool
 }
 
 // Clone makes clone of VMStorage, shares http client.
@@ -36,6 +37,7 @@ func (s *VMStorage) Clone() *VMStorage {
 		queryStep:         s.queryStep,
 		appendTypePrefix:  s.appendTypePrefix,
 		dataSourceType:    s.dataSourceType,
+		disablePathAppend: s.disablePathAppend,
 	}
 }
 
@@ -57,7 +59,7 @@ func (s *VMStorage) BuildWithParams(params QuerierParams) Querier {
 }
 
 // NewVMStorage is a constructor for VMStorage
-func NewVMStorage(baseURL string, authCfg *promauth.Config, lookBack time.Duration, queryStep time.Duration, appendTypePrefix bool, c *http.Client) *VMStorage {
+func NewVMStorage(baseURL string, authCfg *promauth.Config, lookBack time.Duration, queryStep time.Duration, appendTypePrefix bool, c *http.Client, disablePathAppend bool) *VMStorage {
 	return &VMStorage{
 		c:                 c,
 		authCfg:           authCfg,
@@ -66,6 +68,7 @@ func NewVMStorage(baseURL string, authCfg *promauth.Config, lookBack time.Durati
 		lookBack:          lookBack,
 		queryStep:         queryStep,
 		dataSourceType:    NewPrometheusType(),
+		disablePathAppend: disablePathAppend,
 	}
 }
 

app/vmalert/datasource/vm_prom_api.go

@@ -118,7 +118,9 @@ func (s *VMStorage) setPrometheusInstantReqParams(r *http.Request, query string,
 	if s.appendTypePrefix {
 		r.URL.Path += prometheusPrefix
 	}
+	if !s.disablePathAppend {
 		r.URL.Path += prometheusInstantPath
+	}
 	q := r.URL.Query()
 	if s.lookBack > 0 {
 		timestamp = timestamp.Add(-s.lookBack)
@@ -136,7 +138,9 @@ func (s *VMStorage) setPrometheusRangeReqParams(r *http.Request, query string, s
 	if s.appendTypePrefix {
 		r.URL.Path += prometheusPrefix
 	}
+	if !s.disablePathAppend {
 		r.URL.Path += prometheusRangePath
+	}
 	q := r.URL.Query()
 	q.Add("start", fmt.Sprintf("%d", start.Unix()))
 	q.Add("end", fmt.Sprintf("%d", end.Unix()))

app/vmalert/datasource/vm_test.go

@@ -83,7 +83,7 @@ func TestVMInstantQuery(t *testing.T) {
 	if err != nil {
 		t.Fatalf("unexpected: %s", err)
 	}
-	s := NewVMStorage(srv.URL, authCfg, time.Minute, 0, false, srv.Client())
+	s := NewVMStorage(srv.URL, authCfg, time.Minute, 0, false, srv.Client(), false)
 
 	p := NewPrometheusType()
 	pq := s.BuildWithParams(QuerierParams{DataSourceType: &p, EvaluationInterval: 15 * time.Second})
@@ -193,7 +193,7 @@ func TestVMRangeQuery(t *testing.T) {
 	if err != nil {
 		t.Fatalf("unexpected: %s", err)
 	}
-	s := NewVMStorage(srv.URL, authCfg, time.Minute, 0, false, srv.Client())
+	s := NewVMStorage(srv.URL, authCfg, time.Minute, 0, false, srv.Client(), false)
 
 	p := NewPrometheusType()
 	pq := s.BuildWithParams(QuerierParams{DataSourceType: &p, EvaluationInterval: 15 * time.Second})
@@ -252,6 +252,17 @@ func TestRequestParams(t *testing.T) {
 				checkEqualString(t, prometheusInstantPath, r.URL.Path)
 			},
 		},
+		{
+			"prometheus path with disablePathAppend",
+			false,
+			&VMStorage{
+				dataSourceType:    NewPrometheusType(),
+				disablePathAppend: true,
+			},
+			func(t *testing.T, r *http.Request) {
+				checkEqualString(t, "", r.URL.Path)
+			},
+		},
 		{
 			"prometheus prefix",
 			false,
@@ -263,6 +274,18 @@ func TestRequestParams(t *testing.T) {
 				checkEqualString(t, prometheusPrefix+prometheusInstantPath, r.URL.Path)
 			},
 		},
+		{
+			"prometheus prefix with disablePathAppend",
+			false,
+			&VMStorage{
+				dataSourceType:    NewPrometheusType(),
+				appendTypePrefix:  true,
+				disablePathAppend: true,
+			},
+			func(t *testing.T, r *http.Request) {
+				checkEqualString(t, prometheusPrefix, r.URL.Path)
+			},
+		},
 		{
 			"prometheus range path",
 			true,
@@ -273,6 +296,17 @@ func TestRequestParams(t *testing.T) {
 				checkEqualString(t, prometheusRangePath, r.URL.Path)
 			},
 		},
+		{
+			"prometheus range path with disablePathAppend",
+			true,
+			&VMStorage{
+				dataSourceType:    NewPrometheusType(),
+				disablePathAppend: true,
+			},
+			func(t *testing.T, r *http.Request) {
+				checkEqualString(t, "", r.URL.Path)
+			},
+		},
 		{
 			"prometheus range prefix",
 			true,
@@ -284,6 +318,18 @@ func TestRequestParams(t *testing.T) {
 				checkEqualString(t, prometheusPrefix+prometheusRangePath, r.URL.Path)
 			},
 		},
+		{
+			"prometheus range prefix with disablePathAppend",
+			true,
+			&VMStorage{
+				dataSourceType:    NewPrometheusType(),
+				appendTypePrefix:  true,
+				disablePathAppend: true,
+			},
+			func(t *testing.T, r *http.Request) {
+				checkEqualString(t, prometheusPrefix, r.URL.Path)
+			},
+		},
 		{
 			"graphite path",
 			false,

app/vmalert/remoteread/init.go

@@ -12,7 +12,7 @@ import (
 var (
 	addr = flag.String("remoteRead.url", "", "Optional URL to VictoriaMetrics or vmselect that will be used to restore alerts "+
 		"state. This configuration makes sense only if `vmalert` was configured with `remoteWrite.url` before and has been successfully persisted its state. "+
-		"E.g. http://127.0.0.1:8428")
+		"E.g. http://127.0.0.1:8428. See also -remoteRead.disablePathAppend")
 	basicAuthUsername     = flag.String("remoteRead.basicAuth.username", "", "Optional basic auth username for -remoteRead.url")
 	basicAuthPassword     = flag.String("remoteRead.basicAuth.password", "", "Optional basic auth password for -remoteRead.url")
 	basicAuthPasswordFile = flag.String("remoteRead.basicAuth.passwordFile", "", "Optional path to basic auth password to use for -remoteRead.url")
@@ -26,6 +26,7 @@ var (
 		"By default system CA is used")
 	tlsServerName = flag.String("remoteRead.tlsServerName", "", "Optional TLS server name to use for connections to -remoteRead.url. "+
 		"By default the server name from -remoteRead.url is used")
+	disablePathAppend = flag.Bool("remoteRead.disablePathAppend", false, "Whether to disable automatic appending of '/api/v1' path to the configured -remoteRead.url.")
 )
 
 // Init creates a Querier from provided flag values.
@@ -43,5 +44,5 @@ func Init() (datasource.QuerierBuilder, error) {
 		return nil, fmt.Errorf("failed to configure auth: %w", err)
 	}
 	c := &http.Client{Transport: tr}
-	return datasource.NewVMStorage(*addr, authCfg, 0, 0, false, c), nil
+	return datasource.NewVMStorage(*addr, authCfg, 0, 0, false, c, *disablePathAppend), nil
 }

docs/vmalert.md

@@ -500,6 +500,8 @@ The shortlist of configuration flags is the following:
     	Optional bearer auth token to use for -remoteRead.url.
   -remoteRead.bearerTokenFile string
     	Optional path to bearer token file to use for -remoteRead.url.
+  -remoteRead.disablePathAppend
+    	Whether to disable automatic appending of '/api/v1/query' path to the configured -remoteRead.url.
   -remoteRead.ignoreRestoreErrors
     	Whether to ignore errors from remote storage when restoring alerts state on startup. (default true)
   -remoteRead.lookback duration