Logging

When building workflow apps, you can use both function-level and app-level logging to troubleshoot and debug your app.

Local app logs

When developing locally, you can log information to the console of the terminal window where you are running your development server with calls to console.log. Calls to console.log are processed while your local developer server is running.

Let's use the Virtual Running Buddies sample app as an example. Say you'd like to print out items that are getting stored in your datastore to verify that you're getting the type of data you expect. Within the log_run.ts file, we'll add a console.log call to the function that logs a run and stores it in the datastore as follows:

// log_run.ts
export default SlackFunction(LogRunFunction, async ({ inputs, client }) => {
  const { distance, rundate, runner } = inputs;
  const uuid = crypto.randomUUID();

  const putResponse = await client.apps.datastore.put({
    datastore: RUN_DATASTORE,
    item: {
      id: uuid,
      runner: runner,
      distance: distance,
      rundate: rundate,
    },
  });

  if (!putResponse.ok) {
    return { error: `Failed to store run: ${putResponse.error}` };
  }
  console.log(putResponse); // add this line
  return { outputs: {} };
});

Now when you run your app locally, you'll see output similar to the following in your terminal window:

✨  yourname123 of Your DevEnv
Connected, awaiting events
2023-03-29 07:51:07 [info] [Wf050D7QTLR5] (Trace=Tr050M6Y6QF8) Execution started for workflow 'Log a run'
2023-03-29 07:51:07 [info] [Wf050D7QTLR5] (Trace=Tr050M6Y6QF8) Executing workflow step 1 of 3
2023-03-29 07:51:07 [info] [Fn010N] (Trace=Tr050M6Y6QF8) Function execution started for builtin function 'Open a form'
2023-03-29 07:51:17 [info] [Fn010N] (Trace=Tr050M6Y6QF8) Function execution completed for function 'Open a form'
2023-03-29 07:51:18 [info] [Wf050D7QTLR5] (Trace=Tr050M6Y6QF8) Execution completed for workflow step 'Open a form'
2023-03-29 07:51:19 [info] [Wf050D7QTLR5] (Trace=Tr050M6Y6QF8) Executing workflow step 2 of 3
{
  ok: true,
  datastore: "running_datastore",
  item: {
    runner: "ABC123DEF45",
    id: "abcd1234-ef56-gh78-ij91-klmnop234567",
    distance: 4.5,
    rundate: "2023-03-29"
  }
}
2023-03-29 07:51:19 [info] [Fn050TKLQJ3V] (Trace=Tr050M6Y6QF8) Function execution started for app function 'Log a run'
2023-03-29 07:51:20 [info] [Fn050TKLQJ3V] (Trace=Tr050M6Y6QF8) Function execution completed for function 'Log a run'
2023-03-29 07:51:21 [info] [Wf050D7QTLR5] (Trace=Tr050M6Y6QF8) Execution completed for workflow step 'Log a run'
2023-03-29 07:51:22 [info] [Wf050D7QTLR5] (Trace=Tr050M6Y6QF8) Executing workflow step 3 of 3
2023-03-29 07:51:22 [info] [Fn0102] (Trace=Tr050M6Y6QF8) Function execution started for builtin function 'Send a message to channel'
2023-03-29 07:51:24 [info] [Fn0102] (Trace=Tr050M6Y6QF8) Function execution completed for function 'Send a message to channel'
2023-03-29 07:51:25 [info] [Wf050D7QTLR5] (Trace=Tr050M6Y6QF8) Execution completed for workflow step 'Send a message to channel'
2023-03-29 07:51:25 [info] [Fn051HE94GSU] (Trace=Tr050TQV7ERG) Function execution completed for function 'Log a run'
2023-03-29 07:51:25 [info] [Wf050D7QTLR5] (Trace=Tr050M6Y6QF8) Execution completed for workflow 'Log a run'

Running console.log emits information that you provide for your app to emit. If you want to see logs for all your app's activity, you'll need to install your app and run slack activity.

Once you run slack activity and select your workspace and local app environment, you'll see output similar to the following in your terminal window:

✨  yourname123 of Your DevEnv
2023-03-29 07:51:07 [info] [Wf050D7QTLR5] (Trace=Tr050M6Y6QF8) Execution started for workflow 'Log a run'
2023-03-29 07:51:07 [info] [Wf050D7QTLR5] (Trace=Tr050M6Y6QF8) Executing workflow step 1 of 3
2023-03-29 07:51:07 [info] [Fn010N] (Trace=Tr050M6Y6QF8) Function execution started for builtin function 'Open a form'
2023-03-29 07:51:17 [info] [Fn010N] (Trace=Tr050M6Y6QF8) Function execution completed for function 'Open a form'
2023-03-29 07:51:18 [info] [Wf050D7QTLR5] (Trace=Tr050M6Y6QF8) Execution completed for workflow step 'Open a form'
2023-03-29 07:51:19 [info] [Wf050D7QTLR5] (Trace=Tr050M6Y6QF8) Executing workflow step 2 of 3
2023-03-29 07:51:19 [info] [Fn050TKLQJ3V] (Trace=Tr050M6Y6QF8) Function execution started for app function 'Log a run'
2023-03-29 07:51:20 [info] [Fn050TKLQJ3V] (Trace=Tr050M6Y6QF8) Function execution completed for function 'Log a run'
2023-03-29 07:51:21 [info] [Wf050D7QTLR5] (Trace=Tr050M6Y6QF8) Execution completed for workflow step 'Log a run'
2023-03-29 07:51:22 [info] [Wf050D7QTLR5] (Trace=Tr050M6Y6QF8) Executing workflow step 3 of 3
2023-03-29 07:51:22 [info] [Fn0102] (Trace=Tr050M6Y6QF8) Function execution started for builtin function 'Send a message to channel'
2023-03-29 07:51:24 [info] [Fn0102] (Trace=Tr050M6Y6QF8) Function execution completed for function 'Send a message to channel'
2023-03-29 07:51:25 [info] [Wf050D7QTLR5] (Trace=Tr050M6Y6QF8) Execution completed for workflow step 'Send a message to channel'
2023-03-29 07:51:25 [info] [Fn051HE94GSU] (Trace=Tr050TQV7ERG) Function execution completed for function 'Log a run'
2023-03-29 07:51:25 [info] [Wf050D7QTLR5] (Trace=Tr050M6Y6QF8) Execution completed for workflow 'Log a run'

✨ For more information about developing locally, refer to local development.

Deployed app logs

After your app is deployed, all calls to console.log will be captured remotely, and will be emitted along with the last seven days of your app's activity via the slack activity command only.

Once deployed, invoke some of your app's workflows, run slack activity, then select your workspace and deployed app environment. In your output, you'll see all of your calls to console.log in addition to the workflow steps and function executions, external auth information, and any errors encountered when running your app.

✨ For more information about deploying your app, refer to deploy to Slack.

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