RPC to Durable Objects should work with multiple wrangler dev sessions

[mgandolfi7]

Describe the solution

I requested #5918 be reopened for tracking however I did not hear back so decided to create a new issue.

Currently, accessing a Durable Object over RPC in multiple wrangler instances causes this error:

Cannot access `MyDurableObject#myMethod` as Durable Object RPC is not yet supported between multiple `wrangler dev` sessions.

To get around this, you can start all your workers/durable objects in one command (same Miniflare instance) by chaining -c however, this is not ideal for several reasons such as large monorepos with dozens of workers and durable objects depending on each other. Another workaround is to create a wrapper instance that extends WorkerEntrypoint which just proxies everything to the DO but this is an extra layer and a ton of duplication.

[emily-shen]

Hey, thanks for making a feature request - this is something we've still been thinking about internally and figuring out how to implement.

Can you elaborate about what's not ergonomic about using wrangler dev -c -c etc. in big multiworker setups or monorepos? we'd like to (also) improve the experience there if there's anything specific.

[mgandolfi7]

No problem and appreciate the prompt response.

Can you elaborate about what's not ergonomic about using wrangler dev -c -c etc. in big multiworker setups or monorepos?

I can't think of anything that could be better/more ergonomic with the current implementation of launching multiple workers in a single miniflare instance. I think it's a great option to have.

In our case, we want every worker/do to be independent and have turborepo manage the dependency graph. That way we can just do something like: turbo dev -F workerUsingVite -F wranglerWorker - F wranglerDurableObject -F workerWithCustomBuildStep -F containerDockerDurableObject and turborepo handles all orchestration.

I think the docs do a good job of explaining multi dev commands vs single dev instance. The only problem is that the Note section about combining approaches does not help for DOs since they will be 2 different instances.

I do have some other ideas/wishes about better monorepo support but none are related to this so I'll likely make a separate issue/request.

[petebacondarwin]

Should be fixed by #12600