app/vmauth: add ability to override the username label value for vmauth_user_requests_total metric by specifying name option in -auth.config

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1805

app/vmauth/README.md

@@ -147,6 +147,14 @@ It is recommended protecting `/-/reload` endpoint with `-reloadAuthKey` command-
 `vmauth` exports various metrics in Prometheus exposition format at `http://vmauth-host:8427/metrics` page. It is recommended setting up regular scraping of this page
 either via [vmagent](https://docs.victoriametrics.com/vmagent.html) or via Prometheus, so the exported metrics could be analyzed later.
 
+`vmauth` exports `vmauth_user_requests_total` metric with `username` label. The `username` label value equals to `username` field value set in the `-auth.config` file. It is possible to override or hide the value in the label by specifying `name` field. For example, the following config will result in `vmauth_user_requests_total{username="foobar"}` instead of `vmauth_user_requests_total{username="secret_user"}`:
+
+```yml
+users:
+- username: "secret_user"
+  name: "foobar"
+  # other config options here
+```
 
 ## How to build from sources
 

app/vmauth/auth_config.go

@@ -32,6 +32,7 @@ type AuthConfig struct {
 
 // UserInfo is user information read from authConfigPath
 type UserInfo struct {
+	Name        string     `yaml:"name,omitempty"`
 	BearerToken string     `yaml:"bearer_token,omitempty"`
 	Username    string     `yaml:"username,omitempty"`
 	Password    string     `yaml:"password,omitempty"`
@@ -299,14 +300,22 @@ func parseAuthConfig(data []byte) (map[string]*UserInfo, error) {
 			return nil, fmt.Errorf("missing `url_prefix`")
 		}
 		if ui.BearerToken != "" {
+			name := "bearer_token"
+			if ui.Name != "" {
+				name = ui.Name
+			}
 			if ui.Password != "" {
 				return nil, fmt.Errorf("password shouldn't be set for bearer_token %q", ui.BearerToken)
 			}
-			ui.requests = metrics.GetOrCreateCounter(`vmauth_user_requests_total{username="bearer_token"}`)
+			ui.requests = metrics.GetOrCreateCounter(fmt.Sprintf(`vmauth_user_requests_total{username=%q}`, name))
 			byBearerToken[ui.BearerToken] = true
 		}
 		if ui.Username != "" {
-			ui.requests = metrics.GetOrCreateCounter(fmt.Sprintf(`vmauth_user_requests_total{username=%q}`, ui.Username))
+			name := ui.Username
+			if ui.Name != "" {
+				name = ui.Name
+			}
+			ui.requests = metrics.GetOrCreateCounter(fmt.Sprintf(`vmauth_user_requests_total{username=%q}`, name))
 			byUsername[ui.Username] = true
 		}
 		byAuthToken[authToken] = ui

docs/CHANGELOG.md

@@ -6,6 +6,8 @@ sort: 15
 
 ## tip
 
+* FEATURE: vmauth: allow using optional `name` field in configs. This field is then used as `username` label value for `vmauth_user_requests_total` metric. See [this feature request](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1805).
+
 * BUGFIX: vmstorage [enterprise](https://victoriametrics.com/enterprise.html): added missing `vm_tenant_used_tenant_bytes` metric, which shows the approximate per-tenant disk usage. See [these docs](https://docs.victoriametrics.com/PerTenantStatistic.html) and [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1605).
 * BUGFIX: vmauth: properly take into account the value passed to `-maxIdleConnsPerBackend` command-line flag. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1300).
 * BUGFIX: vmagent: fix [reading data from Kafka](https://docs.victoriametrics.com/vmagent.html#reading-metrics-from-kafka).

docs/vmauth.md

@@ -151,6 +151,14 @@ It is recommended protecting `/-/reload` endpoint with `-reloadAuthKey` command-
 `vmauth` exports various metrics in Prometheus exposition format at `http://vmauth-host:8427/metrics` page. It is recommended setting up regular scraping of this page
 either via [vmagent](https://docs.victoriametrics.com/vmagent.html) or via Prometheus, so the exported metrics could be analyzed later.
 
+`vmauth` exports `vmauth_user_requests_total` metric with `username` label. The `username` label value equals to `username` field value set in the `-auth.config` file. It is possible to override or hide the value in the label by specifying `name` field. For example, the following config will result in `vmauth_user_requests_total{username="foobar"}` instead of `vmauth_user_requests_total{username="secret_user"}`:
+
+```yml
+users:
+- username: "secret_user"
+  name: "foobar"
+  # other config options here
+```
 
 ## How to build from sources