Nextjs "server Sentry.Init()" is never called if npm run build happened in different environment than hosting

[jtn-junedesk]

• Review the documentation: https://docs.sentry.io/
• Search for existing issues: https://github.com/getsentry/sentry-javascript/issues
• Use the latest release: https://github.com/getsentry/sentry-javascript/releases
• Provide a link to the affected event from your Sentry account

Package + Version

• @sentry/browser
• @sentry/node
• raven-js
• raven-node (raven for node)
• other: @sentry/nextjs

Version:

6.5.1

Description

I use Github Actions to build my nextjs application, then deploy artifacts to a NodeJS Server hosted elsewhere.
https://nextjs.org/docs/deployment#nodejs-server

During npm run build @sentry/nextjs creates a file .env.local and sets an environment variable SENTRY_SERVER_INIT_PATH. The value of said variable is an absolute path i.e. C:\some_path_to_project\.next\server\sentry\initServerSDK.js

During npm run start process.env.SENTRY_SERVER_INIT_PATH is used to require initServerSDK.js. However, npm run start is called after artifacts have been uploaded to a different environment running a NodeJS server. Because of this, the absolute path of process.env.SENTRY_SERVER_INIT_PATH is no longer valid.

initServerSDK.js cannot be found and Sentry.Init() is never called - serverside logging does not happen.

Source code

sentry-javascript/packages/nextjs/src/utils/config.ts

Line 161 in e44bc63

setRuntimeEnvVars(projectDir, { SENTRY_SERVER_INIT_PATH: serverSDKInitOutputPath });

sentry-javascript/packages/nextjs/src/utils/instrumentServer.ts

Line 117 in e44bc63

require(process.env.SENTRY_SERVER_INIT_PATH as string);

[edoko]

I am having the same problem and same version.

I running the production mode, and it created .env.local, it has SENTRY_SERVER_INIT_PATH=/project_path/.next/server/sentry/initServerSDK.js.
But, .next/server/sentry is not here.
And Sentry logger is not working.

[AbhiPrasad]

Hey! Thank you for reporting, this was definitely an oversight on our part. We’ve merged in a fix for this bug, which will go out in the next release of the SDK.

I will update this issue when that release is out.

[jtn-junedesk]

@AbhiPrasad Thank you for fixing this so quickly! Looking forward to the release 👍

[jtn-junedesk]

@AbhiPrasad Looking through the code, I am a bit curious why you have chosen a 2 step model (create/consume) which creates a disk file dependency (.env.local).

Could instrumentServer.ts not simply do this:

import * as path from 'path';
import { SERVER_SDK_INIT_PATH } from './utils/config';

[...]

const serverSdk = path.join(this.server.serverBuildDir, config.SERVER_SDK_INIT_PATH);
require(serverSdk);

With this solution you would not need to create .env.local during build and could remove some complexity :)

[AbhiPrasad]

I am a bit curious why you have chosen a 2 step model (create/consume) which creates a disk file dependency (.env.local).

Great question @jtn-junedesk. We chose to take this approach because we can't really make any assumptions where webpack will place Sentry assets. In addition, a user's custom setup might move things around also.

To get an idea of all the possible permutations of dir/path locations, take a look at all the conditionals here: https://github.com/vercel/next.js/blob/3f2379a9ff88dd4a1c775862006d233c1510e5fd/packages/next/build/webpack-config.ts#L928-L939. Serverless options also can change the path: https://github.com/vercel/next.js/blob/3f2379a9ff88dd4a1c775862006d233c1510e5fd/packages/next/build/webpack-config.ts#L303-L309. I'm sure they will add even more options in the future.

We decided that the 2-step solution was the easiest for us to implement while minimizing possible conflicts with user/default configurations. It is also much less likely to break if (when) next or webpack changes the way they do things in the future.

Despite what I said above, it might be possible to find a way to get the paths to work properly here. If someone finds a way, suggestions + PRs always welcome :)

[jtn-junedesk]

Thank you for a great reply @AbhiPrasad - and for providing references.

However, from reading next-server.ts, my understanding is that next.js is already handling those scenarios (path locations, distDir, serverless) when they expose .serverBuildDir. If we use the property which next.js has already exposed, my feeling is that this would be the most safe option. This means that we have to make zero assumptions and give next.js 100% responsibility for telling us where the directory is.

If they add more options in the future, I would expect .serverBuildDir to reflect this.

You can see their current implementation here:
https://github.com/vercel/next.js/blob/0402fc459eb12a775372172a351f3a3f4fee83e3/packages/next/next-server/server/next-server.ts#L243-L246

I case this makes sense, I would gladly dedicate some time to creating a PR :)

[AbhiPrasad]

@jtn-junedesk Your thoughts definitely make sense to me. If you could open a PR we can discuss further.

Thank you so much for helping us iterate on this sdk, it’s greatly appreciated!

[jacob-indieocean]

I would really prefer sentry did not modify my .env.local file (especially without documentation!).

I was really surprised to see that there and I have no idea if I should duplicate that manually in all my environments.

[lobsterkatie]

Hi, @jacob-indieocean - we in fact no longer do.

Cheers!