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Custom Functions (CFs) can get debugged in production and when developing locally. While there are many ways to debug code, and specific IDEs that provide special tooling, here we're addressing the most general ways to debug custom functions in 8base.

Production Debugging

When a CF gets deployed to a workspace it becomes visible in the Logic screen on the 8base console. This both confirms that the function was successfully deployed and is where the CFs execution logs can get reviewed and tailed in real-time. Logs report each request uniquely.

START RequestId: 250be4db-cac4-425a-9d4c-24f94ccefd7f Version: $LATEST
END RequestId: 250be4db-cac4-425a-9d4c-24f94ccefd7f
REPORT RequestId: 250be4db-cac4-425a-9d4c-24f94ccefd7f Duration: 0.54 ms Billed Duration: 100 ms Memory Size: 1536 MB Max Memory Used: 88 MB XRAY TraceId: 1-5d794811-0a64a1f6f0c03eb43a0df3b0 SegmentId: 3353cda75bd91f53 Sampled: false

Using the console.log and console.error methods inside of a CF will output any given argument to the execution logs. Knowing this, a developer has the flexibility to enrich their logs as needed, as well as output arguments for debugging purposes.

export default async (event: any, ctx: any) : Promise<LocalizeResult> => {
/* To inspecting the object in production */
console.log('DEBUG: ',;
// more code

Local Debugging

The suggested method for debugging CFs locally requires a Chrome browser. Once installed, add this script to the project’s package.json file:

"scripts": {
"debug": "node --inspect $(npm root -g)/8base-cli/dist/index.js "

The script runs node --inspect, and then finds the path to the 8base-cli package installed globally on the machine - building a path to the executable (e.g., /usr/local/lib/node_modules/8base-cli/dist/index.js). Whether yarn or npm is being used won’t matter.

Next, place a debugger in the code where you want to pause the execution. When debugging an error, insure that the debugger is placed before error occurs.

export default async (event: any, ctx: any) : Promise<LocalizeResult> => {
// some code
// some error.
new DontExist({ something: 'is wrong' });

Before invoking the CF, open Chrome and visit chrome://inspect. Click the Open dedicated DevTools for Node link. The window that opens is the Chrome developer console where you’re debugger will be stopped.

You can now start debugging the function using the invoke-local command.

npm run debug invoke-local FUNCTION_NAME -p /path/to/mock.json
# or
yarn debug invoke-local FUNCTION_NAME -p /path/to/mock.json

When invoke-local is called, the 8base CLI first builds the code before running it. Therefore, it's always the built code that is being debugged. This is why the source script being debugged, when shown in the Chrome window, might look unfamiliar.

Know that this doesn't affect any access to scope for the debugger, but imported modules and function arguments might have been assigned abstracted names. If you want to inspect a module, it’s better to assign it to a variable so that the name will be the same. For example;

import AWS from 'aws-sdk';

export default async (event: any, ctx: any) : Promise<LocalizeResult> => {
// Want to inspect the AWS module?
const aws = AWS;
// Now in the debugger you can be sure aws variable is available.
// more code
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