Pass debug log level to http-proxy-middleware

Signed-off-by: Boris Bera <bbera@coveo.com>

.changeset/twenty-insects-live.md

@@ -2,4 +2,4 @@
 '@backstage/plugin-proxy-backend': patch
 ---
 
-Pass the current log level to `http-proxy-middleware` to ensure that proxies requests are shown when log level is set to `debug`.
+Ensure that `@backstage/plugin-proxy-backend` logs the requests that it proxies when log level is set to `debug`.

plugins/proxy-backend/src/service/router.ts

@@ -63,12 +63,6 @@ export interface ProxyConfig extends Options {
   reviveRequestBody?: boolean;
 }
 
-function isValidHttpProxyMiddlewareLogLevel(
-  level: string,
-): level is Exclude<Options['logLevel'], undefined> {
-  return ['debug', 'info', 'warn', 'error', 'silent'].includes(level);
-}
-
 // Creates a proxy middleware, possibly with defaults added on top of the
 // given config.
 export function buildMiddleware(
@@ -127,9 +121,11 @@ export function buildMiddleware(
 
   // Attach the logger to the proxy config
   fullConfig.logProvider = () => logger;
-  if (isValidHttpProxyMiddlewareLogLevel(logger.level)) {
-    fullConfig.logLevel = logger.level;
-  }
+  // http-proxy-middleware uses this log level to check if it should log the
+  // requests that it proxies. Setting this to the most verbose log level
+  // ensures that it always logs these requests. Our logger ends up deciding
+  // if the logs are displayed or not.
+  fullConfig.logLevel = 'debug';
 
   // Only return the allowed HTTP headers to not forward unwanted secret headers
   const requestHeaderAllowList = new Set<string>(