Update e2e instructions

[ryaplots]

Summary

References https://github.com/TheThingsIndustries/lorawan-stack/issues/4471
This PR updates the documentation regarding how to run the stack locally for frontend development and how to run the e2e tests locally.

Changes

• Update serve-dev-webui.js tool to support cypress tests
• Update docs

Testing

Steps

1. Run e2e tests with laucher tool following development.md

Checklist

• Scope: The referenced issue is addressed, there are no unrelated changes.
• Compatibility: The changes are backwards compatible with existing API, storage, configuration and CLI, according to the compatibility commitments in README.md for the chosen target branch.
• Documentation: Relevant documentation is added or updated.
• Testing: The steps/process to test this feature are clearly explained including testing for regressions.
• Infrastructure: If infrastructural changes (e.g., new RPC, configuration) are needed, a separate issue is created in the infrastructural repositories.
• Changelog: Significant features, behavior changes, deprecations and fixes are added to CHANGELOG.md.
• Commits: Commit messages follow guidelines in CONTRIBUTING.md, there are no fixup commits left.

[johanstokking]

So all these env blocks are only needed when not using dev:serveDevWebui, right?

If that is the case, can this be moved lower in the page for advanced use?

[johanstokking]

What I'm getting is tons of stack errors about Redis keys not existing:

[stack] WARN    Task failed     {"error": "error:pkg/redis:store (store error)", "error_cause": "NOGROUP No such key 'ttn:v3:is:tasks:telemetry:ready' or consumer group 'is' in XREADGROUP with GROUP option", "invocation": 13, "namespace": "identityserver", "task_id": "is_telemetry_consumer_0"}
[stack] ERROR   Failed to pop entry from downlink task queue    {"error": "error:pkg/redis:store (store error)", "error_cause": "NOGROUP No such key 'ttn:v3:ns:tasks:downlink:ready' or consumer group 'ns' in XREADGROUP with GROUP option", "namespace": "networkserver"}

This is probably because of dev:redisFlush. But shoudn't there be some sort of restore of the Redis database? Or am I doing something wrong still?

[ryaplots]

This is probably because of dev:redisFlush. But shoudn't there be some sort of restore of the Redis database? Or am I doing something wrong still?

I am also seeing these warnings. It's weird because we before we also didn't restore the Redis db, but these warnings weren't there. Besides, dev:redisFlush only deletes the keys that were created during testing, it does not drop the db.

[johanstokking]

I am also seeing these warnings. It's weird because we before we also didn't restore the Redis db, but these warnings weren't there. Besides, dev:redisFlush only deletes the keys that were created during testing, it does not drop the db.

I wonder how it worked before. This dev:redisFlush does actually flush the database, as in it looks like it deletes all keys. That's an issue because there are some "system" keys that are not tested-related that should not be deleted.

[ryaplots]

I am also seeing these warnings. It's weird because we before we also didn't restore the Redis db, but these warnings weren't there. Besides, dev:redisFlush only deletes the keys that were created during testing, it does not drop the db.

I wonder how it worked before. This dev:redisFlush does actually flush the database, as in it looks like it deletes all keys. That's an issue because there are some "system" keys that are not tested-related that should not be deleted.

I see. How do I know which keys are test-related and delete only those?

[johanstokking]

I am also seeing these warnings. It's weird because we before we also didn't restore the Redis db, but these warnings weren't there. Besides, dev:redisFlush only deletes the keys that were created during testing, it does not drop the db.

I wonder how it worked before. This dev:redisFlush does actually flush the database, as in it looks like it deletes all keys. That's an issue because there are some "system" keys that are not tested-related that should not be deleted.

I see. How do I know which keys are test-related and delete only those?

I think that everything can be deleted except:

2) "ttn:v3:ns:tasks:downlink:ready"
3) "ttn:v3:ns:tasks:downlink:input"
8) "ttn:v3:ns:application-uplinks:uplinks"

Also make sure that telemetry is disabled in the config (if that is not already the case).

Alternatively, as part of flushing the Redis database, the stack may also be restarted. Then it recreates these Redis keys automatically. Not sure if it is possible/desired to restart the stack between tests though?

[nicholaspcr]

Tried to run the E2E locally it was really easy to setup, very helpful.

I left some comments regarding the readability of the development.md.