From 5018bcbffd94047e89e42b818c7a3882abfc2e23 Mon Sep 17 00:00:00 2001
From: Jeremy Fehr <jfehr@google.com>
Date: Mon, 8 Jul 2024 16:30:30 -0700
Subject: [PATCH] fix: parse structured logs, and handle ANSI escape codes in
 logs

---
 .eslintrc.json |  5 ++++-
 src/logger.ts  | 19 +++++++++++++++----
 test/logger.ts | 38 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 57 insertions(+), 5 deletions(-)

diff --git a/.eslintrc.json b/.eslintrc.json
index eb23147b..1281c0ee 100644
--- a/.eslintrc.json
+++ b/.eslintrc.json
@@ -1,3 +1,6 @@
 {
-    "extends": "./node_modules/gts"
+    "extends": "./node_modules/gts",
+    "rules": {
+        "no-control-regex": 0
+    }
 }
diff --git a/src/logger.ts b/src/logger.ts
index 90595f78..b9d4e219 100644
--- a/src/logger.ts
+++ b/src/logger.ts
@@ -127,14 +127,22 @@ export function getModifiedData(
     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 (!(SEVERITY in dataWithContext)) {
+      dataWithContext[SEVERITY] = stderr ? 'ERROR' : 'INFO';
+    }
   } else {
     dataWithContext = getTextWithContext(processedData, currentContext);
-  }
-  if (stderr) {
-    dataWithContext[SEVERITY] = 'ERROR';
+    dataWithContext[SEVERITY] = stderr ? 'ERROR' : 'INFO';
   }
 
   return JSON.stringify(dataWithContext) + '\n';
@@ -178,6 +186,9 @@ function processData(data: Uint8Array | string, encoding?: BufferEncoding) {
     return {isJSON: false, processedData: data};
   }
 
+  // strip any leading ANSI terminal codes from the start of 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) {
diff --git a/test/logger.ts b/test/logger.ts
index 732598b4..0111d7f1 100644
--- a/test/logger.ts
+++ b/test/logger.ts
@@ -148,4 +148,42 @@ describe('getModifiedData', () => {
       ) + '\n';
     assert.equal(modifiedData, expectedOutput);
   });
+
+  it('parses firebase log severity', () => {
+    const modifiedData = <string>(
+      getModifiedData('testing info log level', undefined, false)
+    );
+    assert.equal('INFO', JSON.parse(modifiedData)['severity']);
+    assert.equal('testing info log level', JSON.parse(modifiedData)['message']);
+  });
+
+  it('parses firebase warning severity', () => {
+    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', () => {
+    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']
+    );
+  });
 });