[Heartbeat] Better handling of subfolders in package.json

[andrewvc]

It is currently the case that heartbeat browser options only copy the exact folder specified to the tmp directory used for actually running it. This can be confusing to users who specify a path in a subfolder below their package.json, and can result in failed includes etc.

This issue proposes:

1. Returning an error if the specified folder does not contain a package.json file
2. Adding a new filter_journeys.folder option to let users actually filter by folder.

In the case of using the new filter_journeys.folder option heartbeat will run npm @elastic/synthetics $filter_journeys.folder to do the filtering.

[elasticmachine]

Pinging @elastic/uptime (Team:Uptime)

[vigneshshanmugam]

Some thoughts here,

• Isnt this already solved by target_directory?
• Also, if the folder does not contain package.json, Synthetics runner already does error out which would be captured as part of stderr with our new changes - [Heartbeat]: catch all error handler for browser jobs #30013

[andrewvc]

Hmmm, the user who reported this was using local folders. So maybe it's just those that need additional error handling?

target_directory only unzips that folder.

If your folder structure is:

README.md
synthetics/package.json
synthetics/tests-a/test-a.ts
synthetics/tests-b/test-b.ts
synthetics/common.ts

and you have a target_directory of synthetics/tests-a things won't work right since we're missing the package.json and presumably the user wants common.ts (if it's used as a require)

In this case, what I'm saying is there'd be a separate filter_journeys.folder option that would be set to synthetics/tests-a, but the user would set synthetics as the target_directory

[vigneshshanmugam]

you have a target_directory of synthetics/tests-a things won't work right since we're missing the package.json

If the user passed in synthetics/tests-a as the local path, then he wont get message from Synthetics runner as we cannot find the root package.json as we dont know the project structure due to missing parent folder.

In this case, the runner would throw error as it cannot find root package.json file - https://github.com/elastic/synthetics/blob/251f504aa859ab0c4a119b5a59f7bbc84c586510/src/helpers.ts#L151

I am not sure about if its worth adding folder level filtering, We do already support names and tags filtering.

[andrewvc]

We agreed that we'll not add the new filter_journeys option, but we will change the target_directory option's behavior. We will now unpack the full zip and just cwd to that directory to avoid dependency issues.

[paulb-elastic]

Replaced by the PUSH option