Deprecate label flag and Align label filter flag with attribute filter flag name

.chloggen/3218-align-label-filter-flag.yaml

@@ -0,0 +1,16 @@
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: deprecation
+
+# The name of the component, or a single word describing the area of concern, (e.g. collector, target allocator, auto-instrumentation, opamp, github action)
+component: operator
+
+# A brief description of the change. Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: "Deprecated `label` flag and introduced `labels-filter` flag to align the label filtering with the attribute filtering flag name. The `label` flag will be removed when #3236 issue is resolved."
+
+# One or more tracking issues related to the change
+issues: [3218]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:

.github/workflows/e2e.yaml

@@ -40,7 +40,7 @@ jobs:
          - group: e2e-multi-instrumentation
            setup: "add-multi-instrumentation-params prepare-e2e"
          - group: e2e-metadata-filters
-           setup: "add-operator-arg OPERATOR_ARG='--annotations-filter=.*filter.out --annotations-filter=config.*.gke.io.* --labels=.*filter.out' prepare-e2e"
+           setup: "add-operator-arg OPERATOR_ARG='--annotations-filter=.*filter.out --annotations-filter=config.*.gke.io.* --labels-filter=.*filter.out' prepare-e2e"
          - group: e2e-automatic-rbac
            setup: "add-rbac-permissions-to-operator prepare-e2e"
     steps:

main.go

@@ -133,6 +133,7 @@ func main() {
 		autoInstrumentationNginx         string
 		autoInstrumentationGo            string
 		labelsFilter                     []string
+		tmplabelsFilter                  []string
 		annotationsFilter                []string
 		webhookPort                      int
 		tlsOpt                           tlsConfig
@@ -170,7 +171,8 @@ func main() {
 	stringFlagOrEnv(&autoInstrumentationGo, "auto-instrumentation-go-image", "RELATED_IMAGE_AUTO_INSTRUMENTATION_GO", fmt.Sprintf("ghcr.io/open-telemetry/opentelemetry-go-instrumentation/autoinstrumentation-go:%s", v.AutoInstrumentationGo), "The default OpenTelemetry Go instrumentation image. This image is used when no image is specified in the CustomResource.")
 	stringFlagOrEnv(&autoInstrumentationApacheHttpd, "auto-instrumentation-apache-httpd-image", "RELATED_IMAGE_AUTO_INSTRUMENTATION_APACHE_HTTPD", fmt.Sprintf("ghcr.io/open-telemetry/opentelemetry-operator/autoinstrumentation-apache-httpd:%s", v.AutoInstrumentationApacheHttpd), "The default OpenTelemetry Apache HTTPD instrumentation image. This image is used when no image is specified in the CustomResource.")
 	stringFlagOrEnv(&autoInstrumentationNginx, "auto-instrumentation-nginx-image", "RELATED_IMAGE_AUTO_INSTRUMENTATION_NGINX", fmt.Sprintf("ghcr.io/open-telemetry/opentelemetry-operator/autoinstrumentation-apache-httpd:%s", v.AutoInstrumentationNginx), "The default OpenTelemetry Nginx instrumentation image. This image is used when no image is specified in the CustomResource.")
-	pflag.StringArrayVar(&labelsFilter, "label", []string{}, "Labels to filter away from propagating onto deploys. It should be a string array containing patterns, which are literal strings optionally containing a * wildcard character. Example: --label=.*filter.out will filter out labels that looks like: label.filter.out: true")
+	pflag.StringArrayVar(&labelsFilter, "labels-filter", []string{}, "Labels to filter away from propagating onto deploys. It should be a string array containing patterns, which are literal strings optionally containing a * wildcard character. Example: --labels-filter=.*filter.out will filter out labels that looks like: label.filter.out: true")
+	pflag.StringArrayVar(&tmplabelsFilter, "label", []string{}, "(Deprecated, please use the labels-filter flag) Labels to filter away from propagating onto deploys. It should be a string array containing patterns, which are literal strings optionally containing a * wildcard character. Example: --label=.*filter.out will filter out labels that looks like: label.filter.out: true")
 	pflag.StringArrayVar(&annotationsFilter, "annotations-filter", []string{}, "Annotations to filter away from propagating onto deploys. It should be a string array containing patterns, which are literal strings optionally containing a * wildcard character. Example: --annotations-filter=.*filter.out will filter out annotations that looks like: annotation.filter.out: true")
 	pflag.StringVar(&tlsOpt.minVersion, "tls-min-version", "VersionTLS12", "Minimum TLS version supported. Value must match version names from https://golang.org/pkg/crypto/tls/#pkg-constants.")
 	pflag.StringSliceVar(&tlsOpt.cipherSuites, "tls-cipher-suites", nil, "Comma-separated list of cipher suites for the server. Values are from tls package constants (https://golang.org/pkg/crypto/tls/#pkg-constants). If omitted, the default Go cipher suites will be used")
@@ -181,6 +183,9 @@ func main() {
 	pflag.IntVar(&webhookPort, "webhook-port", 9443, "The port the webhook endpoint binds to.")
 	pflag.Parse()
 
+	// Using labelfilters both from label and labels-filter flags, until label flag is removed
+	labelsFilter = append(labelsFilter, tmplabelsFilter...)
+
 	opts.EncoderConfigOptions = append(opts.EncoderConfigOptions, func(ec *zapcore.EncoderConfig) {
 		ec.MessageKey = encodeMessageKey
 		ec.LevelKey = encodeLevelKey