vmalert: support auth configs per static_target (#3188)

Allow configuring authorization params per list of targets
in vmalert's notifier config for `static_configs`.

See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2690

Signed-off-by: hagen1778 <roman@victoriametrics.com>

Signed-off-by: hagen1778 <roman@victoriametrics.com>

app/vmalert/README.md

@@ -1158,7 +1158,7 @@ is the following:
 # password and password_file are mutually exclusive.
 basic_auth:
   [ username: <string> ]
-  [ password: <secret> ]
+  [ password: <string> ]
   [ password_file: <string> ]
 
 # Optional `Authorization` header configuration.
@@ -1177,10 +1177,41 @@ authorization:
 tls_config:
   [ <tls_config> ]
 
+# Configures Bearer authentication token via string
+bearer_token: <string>
+# or by passing path to the file with token.
+bearer_token_file: <string>
+
+# Configures OAuth 2.0 authentication
+# see https://prometheus.io/docs/prometheus/latest/configuration/configuration/#oauth2
+oauth2:
+  [ <oauth2_config> ]
+  
+# Optional list of HTTP headers in form `header-name: value`
+# applied for all requests to notifiers
+# For example:
+#  headers:
+#    - "CustomHeader: foo"
+#    - "CustomHeader2: bar"
+headers:
+  [ <string>, ...]
+
 # List of labeled statically configured Notifiers.
+#
+# Each list of targets may be additionally instructed with
+# authorization params. Target's authorization params will
+# inherit params from global authorization params if there
+# are no conflicts.
 static_configs:
-  targets:
+  [ - targets: ]
       [ - '<host>' ]
+      [ oauth2 ]
+      [ basic_auth ]
+      [ authorization ]
+      [ tls_config ]
+      [ bearer_token ]
+      [ bearer_token_file ]
+      [ headers ]
 
 # List of Consul service discovery configurations.
 # See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#consul_sd_config

app/vmalert/notifier/config.go

@@ -68,6 +68,8 @@ type Config struct {
 //	[ - '<host>' ]
 type StaticConfig struct {
 	Targets []string `yaml:"targets"`
+	// HTTPClientConfig contains HTTP configuration for the Targets
+	HTTPClientConfig promauth.HTTPClientConfig `yaml:",inline"`
 }
 
 // UnmarshalYAML implements the yaml.Unmarshaler interface.

app/vmalert/notifier/config_watcher.go

@@ -6,6 +6,7 @@ import (
 	"time"
 
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promauth"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promscrape/discovery/consul"
 	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promscrape/discovery/dns"
 )
@@ -161,12 +162,13 @@ func (cw *configWatcher) start() error {
 	if len(cw.cfg.StaticConfigs) > 0 {
 		var targets []Target
 		for _, cfg := range cw.cfg.StaticConfigs {
+			httpCfg := mergeHTTPClientConfigs(cw.cfg.HTTPClientConfig, cfg.HTTPClientConfig)
 			for _, target := range cfg.Targets {
 				address, labels, err := parseLabels(target, nil, cw.cfg)
 				if err != nil {
 					return fmt.Errorf("failed to parse labels for target %q: %s", target, err)
 				}
-				notifier, err := NewAlertManager(address, cw.genFn, cw.cfg.HTTPClientConfig, cw.cfg.parsedAlertRelabelConfigs, cw.cfg.Timeout.Duration())
+				notifier, err := NewAlertManager(address, cw.genFn, httpCfg, cw.cfg.parsedAlertRelabelConfigs, cw.cfg.Timeout.Duration())
 				if err != nil {
 					return fmt.Errorf("failed to init alertmanager for addr %q: %s", address, err)
 				}
@@ -252,3 +254,30 @@ func (cw *configWatcher) setTargets(key TargetType, targets []Target) {
 	cw.targets[key] = targets
 	cw.targetsMu.Unlock()
 }
+
+// mergeHTTPClientConfigs merges fields between child and parent params
+// by populating child from parent params if they're missing.
+func mergeHTTPClientConfigs(parent, child promauth.HTTPClientConfig) promauth.HTTPClientConfig {
+	if child.Authorization == nil {
+		child.Authorization = parent.Authorization
+	}
+	if child.BasicAuth == nil {
+		child.BasicAuth = parent.BasicAuth
+	}
+	if child.BearerToken == nil {
+		child.BearerToken = parent.BearerToken
+	}
+	if child.BearerTokenFile == "" {
+		child.BearerTokenFile = parent.BearerTokenFile
+	}
+	if child.OAuth2 == nil {
+		child.OAuth2 = parent.OAuth2
+	}
+	if child.TLSConfig == nil {
+		child.TLSConfig = parent.TLSConfig
+	}
+	if child.Headers == nil {
+		child.Headers = parent.Headers
+	}
+	return child
+}

app/vmalert/notifier/config_watcher_test.go

@@ -8,6 +8,8 @@ import (
 	"os"
 	"sync"
 	"testing"
+
+	"github.com/VictoriaMetrics/VictoriaMetrics/lib/promauth"
 )
 
 func TestConfigWatcherReload(t *testing.T) {
@@ -298,3 +300,20 @@ func newFakeConsulServer() *httptest.Server {
 
 	return httptest.NewServer(mux)
 }
+
+func TestMergeHTTPClientConfigs(t *testing.T) {
+	cfg1 := promauth.HTTPClientConfig{Headers: []string{"Header:Foo"}}
+	cfg2 := promauth.HTTPClientConfig{BasicAuth: &promauth.BasicAuthConfig{
+		Username: "foo",
+		Password: promauth.NewSecret("bar"),
+	}}
+
+	result := mergeHTTPClientConfigs(cfg1, cfg2)
+
+	if result.Headers == nil {
+		t.Fatalf("expected Headers to be inherited")
+	}
+	if result.BasicAuth == nil {
+		t.Fatalf("expected BasicAuth tp be present")
+	}
+}

app/vmalert/notifier/testdata/static.good.yaml

@@ -1,7 +1,21 @@
+headers:
+  - 'CustomHeader: foo'
+
 static_configs:
   - targets:
       - localhost:9093
       - localhost:9095
+    basic_auth:
+      username: foo
+      password: bar
+
+  - targets:
+      - localhost:9096
+      - localhost:9097
+    basic_auth:
+      username: foo
+      password: baz
+
 alert_relabel_configs:
   - target_label: "foo"
     replacement: "aaa"

docs/CHANGELOG.md

@@ -32,6 +32,7 @@ The following tip changes can be tested by building VictoriaMetrics components f
 * FEATURE: [vmalert](https://docs.victoriametrics.com/vmalert.html): add `debug` mode to the alerting rule settings for printing additional information into logs during evaluation. See `debug` param in [alerting rule config](https://docs.victoriametrics.com/vmalert.html#alerting-rules).
 * FEATURE: [vmalert](https://docs.victoriametrics.com/vmalert.html): add experimental feature for displaying last 10 states of the rule (recording or alerting) evaluation. The state is available on the Rule page, which can be opened by clicking on `Details` link next to Rule's name on the `/groups` page.
 * FEATURE: [vmalert](https://docs.victoriametrics.com/vmalert.html): allow using extra labels in annotiations. See [this feature request](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3013).
+* FEATURE: [vmalert](https://docs.victoriametrics.com/vmalert.html): allow configuring authorization params per list of targets in vmalert's notifier config for `static_configs`. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2690).
 * FEATURE: [vmagent](https://docs.victoriametrics.com/vmagent.html): minimize the time needed for reading large responses from scrape targets in [stream parsing mode](https://docs.victoriametrics.com/vmagent.html#stream-parsing-mode). This should reduce scrape durations for such targets as [kube-state-metrics](https://github.com/kubernetes/kube-state-metrics) running in a big Kubernetes cluster.
 * FEATURE: [MetricsQL](https://docs.victoriametrics.com/MetricsQL.html): add [sort_by_label_numeric](https://docs.victoriametrics.com/MetricsQL.html#sort_by_label_numeric) and [sort_by_label_numeric_desc](https://docs.victoriametrics.com/MetricsQL.html#sort_by_label_numeric_desc) functions for [numeric sort](https://www.gnu.org/software/coreutils/manual/html_node/Version-sort-is-not-the-same-as-numeric-sort.html) of input time series by the specified labels. See [this feature request](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2938).
 * FEATURE: [vmbackup](https://docs.victoriametrics.com/vmbackup.html) and [vmrestore](https://docs.victoriametrics.com/vmrestore.html): retry GCS operations for up to 3 minutes on temporary failures. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3147).

docs/vmalert.md

@@ -1162,7 +1162,7 @@ is the following:
 # password and password_file are mutually exclusive.
 basic_auth:
   [ username: <string> ]
-  [ password: <secret> ]
+  [ password: <string> ]
   [ password_file: <string> ]
 
 # Optional `Authorization` header configuration.
@@ -1181,10 +1181,41 @@ authorization:
 tls_config:
   [ <tls_config> ]
 
+# Configures Bearer authentication token via string
+bearer_token: <string>
+# or by passing path to the file with token.
+bearer_token_file: <string>
+
+# Configures OAuth 2.0 authentication
+# see https://prometheus.io/docs/prometheus/latest/configuration/configuration/#oauth2
+oauth2:
+  [ <oauth2_config> ]
+  
+# Optional list of HTTP headers in form `header-name: value`
+# applied for all requests to notifiers
+# For example:
+#  headers:
+#    - "CustomHeader: foo"
+#    - "CustomHeader2: bar"
+headers:
+  [ <string>, ...]
+
 # List of labeled statically configured Notifiers.
+#
+# Each list of targets may be additionally instructed with
+# authorization params. Target's authorization params will
+# inherit params from global authorization params if there
+# are no conflicts.
 static_configs:
-  targets:
+  [ - targets: ]
       [ - '<host>' ]
+      [ oauth2 ]
+      [ basic_auth ]
+      [ authorization ]
+      [ tls_config ]
+      [ bearer_token ]
+      [ bearer_token_file ]
+      [ headers ]
 
 # List of Consul service discovery configurations.
 # See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#consul_sd_config