fix: parse structured logs, and handle ANSI escape codes in logs

.eslintrc.json

@@ -1,3 +1,6 @@
 {
-    "extends": "./node_modules/gts"
+    "extends": "./node_modules/gts",
+    "rules": {
+        "no-control-regex": 0
+    }
 }

src/logger.ts

@@ -92,17 +92,17 @@
 }
 
 export const errorHandler = (
   err: Error | any,
   req: express.Request,
   res: express.Response,
   next: express.NextFunction
 ) => {
   interceptStderrWrite();
   res.status(500);
   res.render('error', {error: err});
 };
 
 export function splitArgs(args: any[]) {
   let encoding, cb;
   if (
     args.length > 0 &&
@@ -127,14 +127,24 @@
     return data;
   }
   const {isJSON, processedData} = processData(data, encoding);
-  let dataWithContext;
+
+  let dataWithContext: {
+    message: string | Uint8Array;
+    'logging.googleapis.com/labels': {execution_id: string | undefined};
+    'logging.googleapis.com/trace': string | undefined;
+    'logging.googleapis.com/spanId': string | undefined;
+    severity?: string | undefined;
+  };
   if (isJSON) {
     dataWithContext = getJSONWithContext(processedData, currentContext);
+    if (stderr && !(SEVERITY in dataWithContext)) {
+      dataWithContext[SEVERITY] = 'ERROR';
+    }
   } else {
     dataWithContext = getTextWithContext(processedData, currentContext);
-  }
-  if (stderr) {
-    dataWithContext[SEVERITY] = 'ERROR';
+    if (stderr) {
+      dataWithContext[SEVERITY] = 'ERROR';
+    }
   }
 
   return JSON.stringify(dataWithContext) + '\n';
@@ -152,7 +162,7 @@
   };
 }
 
 function getJSONWithContext(json: any, context: ExecutionContext) {
   if (EXECUTION_CONTEXT_LABELS_KEY in json) {
     json[EXECUTION_CONTEXT_LABELS_KEY]['execution_id'] = context.executionId;
   } else {
@@ -178,6 +188,9 @@
     return {isJSON: false, processedData: data};
   }
 
+  // strip any leading ANSI terminal codes from the decoded data
+  // before trying to parse it as json
+  decodedData = decodedData.replace(/\x1b[[(?);]{0,2}(;?\d)*./g, '');
   try {
     return {isJSON: true, processedData: JSON.parse(decodedData)};
   } catch (e) {

test/logger.ts

@@ -148,4 +148,34 @@ describe('getModifiedData', () => {
       ) + '\n';
     assert.equal(modifiedData, expectedOutput);
   });
+
+  it('parses firebase warning severity and message', () => {
+    const modifiedData = <string>(
+      getModifiedData(
+        '\u001b[33m{"severity":"WARNING","message":"testing warning log level"}\u001b[39m\n',
+        undefined,
+        true
+      )
+    );
+    assert.equal('WARNING', JSON.parse(modifiedData)['severity']);
+    assert.equal(
+      'testing warning log level',
+      JSON.parse(modifiedData)['message']
+    );
+  });
+
+  it('parses firebase error severity and message', () => {
+    const modifiedData = <string>(
+      getModifiedData(
+        '\u001b[31m{"severity":"ERROR","message":"testing error log level"}\u001b[39m\n',
+        undefined,
+        true
+      )
+    );
+    assert.equal('ERROR', JSON.parse(modifiedData)['severity']);
+    assert.equal(
+      'testing error log level',
+      JSON.parse(modifiedData)['message']
+    );
+  });
 });