Batch exports mega-issue

TL;DR

It's proven to be a lot more reliable than our previous streaming system. ## Done - [x] Best effort duplicate removal (#16354) - [x] Revamp exports UI - [x] S3 exports - [x] S3 key templating (#16591) - [x] Add support for file compression (S3/blob storage, #17233, #17269) - [x] Snowflake exports - [x] Postgres exports (#17045, #17178) - [x] Reliability improvements.

Steps

1. On PostHog batch exports (the Temporal-based export system): it is not possible to cancel an already scheduled export. If you need an export stopped, you have to let the scheduled run complete and disable or delete the export config so no further runs are scheduled. Maintainer-confirmed in the batch exports mega-issue.

When to use

You are seeing this: Issue posthog/posthog#15997 (closed, 40 comments): We're moving a lot of currently available apps to a new export system based on Temporal, which exports events in batches. Use this skill when you run into "Batch exports mega-issue".

When not to use

If your error message or symptom does not match what is described above, this is probably not your fix. Search for your exact error text instead of forcing this one to fit.

Versions

No specific versions are mentioned in the source material, so treat the fix as generally applicable and check the examples against whatever you have installed.

Why this happens

The original report does not dig into a root cause. It documents the symptom and the fix that resolved it.

In gh:posthog/posthog#15997 (PostHog Feature Flags), the issue reported was: Issue posthog/posthog#15997 (closed, 40 comments): We're moving a lot of currently available apps to a new export system based on Temporal, which exports events in batches. It's proven to be a lot more reliable than our previous streaming system. ## Done - [x] Best effort duplicate removal (#16354) - [x] Revamp exports UI - [x] S3 exports - [x] S3 key templating (#16591) - [x] Add support for file compression (S3/blob storage, #17233, #17269) - [x] Snowflake exports - [x] Postgres exports (#17045, #17178) - [x] Reliability improvements. The verified resolution from the thread: On PostHog batch exports (the Temporal-based export system): it is not possible to cancel an already scheduled export. If you need an export stopped, you have to let the scheduled run complete and disable or delete the export config so no further runs are scheduled. Maintainer-confirmed in the batch exports mega-issue. Source: mount the host path https at container path //github.com/posthog/posthog/issues/15997