reduce metric cardinaility

Signed-off-by: eternal-flame-AD <yume@yumechi.jp>

packages/backend/src/server/ServerService.ts

@@ -57,7 +57,7 @@ function categorizeRequestPath(path: string): 'api' | 'health' | 'vite' | 'other
 const mRequestTime = metricHistogram({
 	name: 'misskey_http_request_duration_seconds',
 	help: 'Duration of handling HTTP requests in seconds',
-	labelNames: ['host', 'cate', 'method', 'path'],
+	labelNames: ['cate', 'method', 'path'],
 	buckets: [0.001, 0.1, 0.5, 1, 2, 5],
 });
 
@@ -88,19 +88,19 @@ const mTooManyRequestsServed = metricCounter({
 const mAggregateRequestsServed = metricCounter({
 	name: 'misskey_http_requests_served_total',
 	help: 'Total number of HTTP requests served including invalid requests',
-	labelNames: ['host', 'cate', 'status'],
+	labelNames: ['cate', 'status'],
 });
 
 const mRequestsServedByPath = metricCounter({
 	name: 'misskey_http_requests_served_by_path',
 	help: 'Total number of HTTP requests served',
-	labelNames: ['host', 'cate', 'method', 'path', 'status'],
+	labelNames: ['cate', 'method', 'path', 'status'],
 });
 
 const mFatalErrorCount = metricCounter({
 	name: 'misskey_fatal_http_errors_total',
 	help: 'Total number of HTTP errors that propagate to the top level',
-	labelNames: ['host', 'cate', 'method', 'path'],
+	labelNames: ['cate', 'method', 'path'],
 });
 
 const mLastSuccessfulRequest = metricGauge({
@@ -172,7 +172,6 @@ export class ServerService implements OnApplicationShutdown {
 				const url = new URL(request.url, this.config.url);
 				const logPath = sanitizeRequestURI(url.pathname);
 				mFatalErrorCount?.inc({
-					host: request.hostname,
 					method: request.method,
 					path: logPath,
 					cate: categorizeRequestPath(logPath),
@@ -187,7 +186,6 @@ export class ServerService implements OnApplicationShutdown {
 				const received = reply.getHeader('x-request-received') as string;
 
 				mAggregateRequestsServed?.inc({
-					host: request.hostname,
 					cate,
 					status: reply.statusCode,
 				});
@@ -211,7 +209,6 @@ export class ServerService implements OnApplicationShutdown {
 					if (received) {
 						const duration = (+new Date()) - parseInt(received);
 						mRequestTime?.observe({
-							host: request.hostname,
 							method: request.method,
 							cate,
 						}, duration / 1000);
@@ -234,7 +231,6 @@ export class ServerService implements OnApplicationShutdown {
 					const duration = (+new Date()) - parseInt(received);
 
 					mRequestTime?.observe({
-						host: request.hostname,
 						method: request.method,
 						cate,
 						path: logPath,
@@ -253,7 +249,6 @@ export class ServerService implements OnApplicationShutdown {
 				}
 
 				mRequestsServedByPath?.inc({
-					host: request.hostname,
 					method: request.method,
 					path: logPath,
 					cate,