Issue #8510: getPlatformProxy invariant behavior with RPC targets

Summary

Field	Value
Issue	#8510
Title	getPlatformProxy invariant behavior with RPC targets
State	OPEN
Created	2025-03-15
Updated	2025-10-30
Labels	bug
Reporter Version	Wrangler 4.0.0
Current Version	Wrangler 4.60.0

Problem Description

The reporter is trying to access a method on an RPC target through a service binding using getPlatformProxy(). When calling a method on an RpcTarget returned from a getter property, the following error occurs:

TypeError: proxy.env.WORKER_A.foo.getFoo is not a function

The issue is that:

• await proxy.env.WORKER_A.foo returns [Function: foo]
• await proxy.env.WORKER_A.getBar() works correctly (returns "bar")
• await proxy.env.WORKER_A.foo.getFoo() throws TypeError

The same code works correctly when running via wrangler dev on actual workers.

Analysis

Maintainer Response

A maintainer (dario-piotrowicz) acknowledged the issue on 2025-03-17 and indicated the problem is likely caused by foo being a getter, with the proxy not returning the correct value in that case.

Related PRs Searched

• PR #6301 (merged 2024-07-30): "fix: allow getPlatformProxy to handle RPC calls returning objects" - This fixed issues with RpcProperty handling but predates this issue
• PR #10249 (merged 2025-08-15): "Support JSRPC for remote bindings" - Major RPC improvements but doesn't specifically mention getter handling

Changelog Search

• No mention of issue #8510 in wrangler or miniflare changelogs
• No PRs found that directly reference this issue number

Version Gap

• Reporter used Wrangler 4.0.0
• Current version is 4.60.0 (significant gap with many releases)

Recommendation

KEEP OPEN - This issue should remain open because:

1. Acknowledged by maintainer: The issue was confirmed by a Cloudflare team member who identified the likely root cause (getter property handling)
2. No fix found: No PRs reference this issue, and the issue number doesn't appear in changelogs
3. Valid bug: The behavior difference between getPlatformProxy() and actual wrangler dev represents a genuine local development parity issue
4. Reproduction available: The reporter provided a minimal reproduction repository

Suggested Actions

1. Verify with current version: The reporter or maintainers should test with Wrangler 4.60.0 to see if any of the RPC improvements have inadvertently fixed this
2. Prioritize fix: Given the impact on local development workflows involving RPC targets with getter properties, this warrants attention
3. Consider labeling: May benefit from additional labels like miniflare or local-dev for better triage

Verdict

Recommendation	Confidence	Reason
KEEP OPEN	High	Maintainer-acknowledged bug with no evidence of a fix