Optionally log the compiler cache keys and accesses (#3583)

etc/config/compiler-explorer.amazon.properties

@@ -20,6 +20,7 @@ pageloadUrl=https://lambda.compiler-explorer.com/pageload
 storageSolution=s3
 healthCheckFilePath=/efs/.health
 showSponsors=true
+logCompilerCacheAccesses=true
 
 eventLoopMeasureIntervalMs=50
 eventLoopLagThresholdWarn=100

lib/base-compiler.js

@@ -246,6 +246,9 @@ export class BaseCompiler {
 
         const key = this.getCompilerCacheKey(compiler, args, options);
         let result = await this.env.compilerCacheGet(key);
+        if (this.env.ceProps('logCompilerCacheAccesses', false)) {
+            logger.info(`Cache ${JSON.stringify(key)} ${result ? 'hit' : 'miss'}`);
+        }
         if (!result) {
             result = await this.env.enqueue(async () => exec.execute(compiler, args, options));
             if (result.okToCache) {