Postgres Support

[acx1729]

This PR adds support for postgres as as a built-in alternative to sqlite for storing orchestration state. There is an other PR, which appears to have gone stale (#33).

[acx1729]

@microsoft-github-policy-service agree company="Open Governance Inc."

[cgillum]

This is great to see! Is it possible to add some tests to confirm that the Postgres backend is working as designed?

[acx1729]

Sure! Working on it.

[Mahanmmi]

I've added the tests with using the current test suit for sqlite, the line is commented out to avoid any errors in automation pipelines since it does need a running postgres and I was not sure if or how you are planning to add it to the pipeline, but I tested it locally and it passes all tests.

[acx1729]

Hi @cgillum

Greetings. Let me know if there is anything else you wish to see in this PR.

Thank you!

[cgillum]

@acx1729 @Mahanmmi looks great, thanks! I've kicked off a test run to see if everything works as expected, and everything looks green.

One more thing: I worry a little about the dev experience of running tests locally and requiring postgres to be running. Would it be possible to have the postgres variant run only when a particular environment variable is specified, and then set that variable as part of the CI process? That way testing with postgres can be opt-in. Ideally, we'd document this environment variable flag in a README.md file in the backend/postgres directory.

[acx1729]

Thank you @Mahanmmi
Hopefully we are all OK @cgillum

[cgillum]

Looks good - thanks!

[umeshdkonda]

@cgillum , any plans to make postgres available in the next version?

[cgillum]

Any plans to make postgres available in the next version?

@umeshdkonda anyone is free to use it now. Are you asking if/when we'll add a release tag for a version that contains this change? Or if you're asking specifically about support in Dapr, we don't currently have plans for that since the existing actor implementation for workflows already supports Postgres as a backend state store.