logsync-bug

Reproduction for a bug in @google-cloud/logging

Steps:

1. Deploy to App Engine Standard environment:

gcloud app deploy app.yaml --project=<PROJECT_ID>

2. Go to console.cloud.google.com/logs/ to view output

Expected:

Here are the first two calls to log.write() in index.js:

const metadata = {
  resource: {
    type: "gae_app",
    labels: {
      module_id: process.env.GAE_SERVICE,
      version_id: process.env.GAE_VERSION,
    },
  },
};

log.write(log.entry(metadata, "A text payload"));
log.write(log.entry(metadata, { message: "A JSON payload" }));

The expected output is something like: (irrelevant details removed)

[
  {
    "textPayload": "A text payload",
    "resource": {
      "type": "gae_app",
      "labels": {
        "version_id": "logsync-bug",
        "module_id": "default",
      }
    },
    "timestamp": "2022-05-06T23:13:23.002Z",
    "logName": "projects/REDACTED_PROJECT_ID/logs/my_log"
  },
  {
    "jsonPayload": {
      "message": "A JSON payload"
    },
    "resource": {
      "type": "gae_app",
      "labels": {
        "module_id": "default",
        "version_id": "logsync-bug"
      }
    },
    "timestamp": "2022-05-06T23:13:23.004Z",
    "logName": "projects/REDACTED_PROJECT_ID/logs/my_log",
    "receiveTimestamp": "2022-05-06T23:13:23.270510336Z"
  }
]

Actual:

The actual output looks like the following: (irrelevant details removed)

[
  {
    "jsonPayload": {
      "message": "A text payload",
      "timestamp": "2022-05-06T23:13:23.002Z",
      "logName": "projects/REDACTED_PROJECT_ID/logs/my_log",
      "resource": {
        "type": "gae_app",
        "labels": {
          "module_id": "default",
          "version_id": "logsync-bug"
        }
      }
    },
    "resource": {
      "type": "gae_app",
      "labels": {
        "zone": "us3",
        "version_id": "logsync-bug",
        "module_id": "default",
        "project_id": "REDACTED_PROJECT_ID"
      }
    },
    "timestamp": "2022-05-06T23:13:23.004560Z",
    "logName": "projects/REDACTED_PROJECT_ID/logs/stdout",
  },
  {
    "jsonPayload": {
      "timestamp": "2022-05-06T23:13:23.004Z",
      "message": {
        "message": "A JSON payload"
      },
      "resource": {
        "labels": {
          "module_id": "default",
          "version_id": "logsync-bug"
        },
        "type": "gae_app"
      },
      "logName": "projects/REDACTED_PROJECT_ID/logs/my_log"
    },
    "resource": {
      "type": "gae_app",
      "labels": {
        "version_id": "logsync-bug",
        "module_id": "default",
        "project_id": "REDACTED_PROJECT_ID",
        "zone": "us3"
      }
    },
    "timestamp": "2022-05-06T23:13:23.005096Z",
    "logName": "projects/REDACTED_PROJECT_ID/logs/stdout",
  }
]

The full output can be seen in downloaded-logs-20220506-191603.json

Fix

I've followed the instructions from the README, copied below. Notice that it says to create an entry, passing metadata and a payload and then call log.write(entry):

// Optional: Create and configure a client
const logging = new Logging();
await logging.setProjectId()
await logging.setDetectedResource()

// Create a LogSync transport, defaulting to `process.stdout`
const log = logging.logSync(logname);
const meta = { /* optional field overrides here */ };
const entry = log.entry(meta, 'Your log message');
log.write(entry);

// Syntax sugar for logging at a specific severity
log.alert(entry);
log.warning(entry);

However, in calls to log.write(entry), it appears the final payload is being populated with the entire entry object passed to log.write() and therefore the entry.metadata isn't being applied at all.

So either the docs are wrong or this is a bug. To fix this it seems would require either:

1. updating the README to show how to correctly create and write to a log.logSync(), or
2. fixing the behavior to match what's in the README.