How to use Stackdriver logging on Cloud Run

Question

I'm trying to get stackdriver logging working for a simple Go app running in Google Cloud Run (fully managed), but don't see stackdriver entries in CloudRun logs.

I've created simplest possible demo app based on "official" stackdriver golang example

Cloud Run docs states that no additional actions should be performed to write stackdriver logs

My service uses default service account

I'm using Go 1.13 to compile code (Dockerfile is copied from Cloud Run example "as-is")

I've tried to deploy it to different regions, with no success

When running container locally, using service account credentials, stackdriver log message does not appear in local terminal or stackdriver console

No matter what, on app start I see only "Before stackdriver logging" followed by "After stackdriver logging" with no other messages\errors in the middle

Here's part of logging code (use link above to get full source, Dockerfile and instructions to build and run the app):

import (
    "context"
    "log"
    "os"
    ...

    "cloud.google.com/go/compute/metadata"
    "cloud.google.com/go/logging"
)

func main() {
    loggingClient, err := stackdriverClient()
    ...
    log.Println("Before stackdriver logging")
    logger.StandardLogger(logging.Info).Println("Stackdriver log")
    if err = logger.Flush(); err != nil {
        log.Fatalf("Failed to flush client: %v", err)
    }
    if err = loggingClient.Close(); err != nil {
        log.Fatalf("Failed to close client: %v", err)
    }
    log.Println("After stackdriver logging")
    ...
}

func stackdriverClient() (client *logging.Client, err error) {
    var projectID string
    if projectID, err = metadata.ProjectID(); err == nil {
        client, err = logging.NewClient(context.Background(), projectID)
    }
    return
}

Why are u trying to use logger.StandardLogger or logging.Info instead of log.Println, which is working? — Ramon Medeiros
@RamonMedeiros because stackdriver logging has great features, like "Trace" and metadata map ("Fields") for easier search and filtering — Slava Medvediev
Update: Looks like logging is working, but default filter for "Cloud Run" does not include stackdriver entries. I'll post an answer soon with all the details. — Slava Medvediev

Slava Medvediev Slava Medvediev · Accepted Answer · 2019-11-17T13:49:18

It turns out that log entries are written successfully
But default Cloud Run filter in logviewer web UI does not include them
Filter expression below worked for me to get all the logs:

resource.type = "project" OR resource.type = "cloud_run_revision"

(service name, location, severity omitted)

"stdout\stderr" log entries match resource.type="cloud_run_revision", while stackdriver log entries match resource.type="project"

Update: I've created a ticket for this in google tracker

How to use Stackdriver logging on Cloud Run

1 Answers