Format discovery responses like a real device in MIM requester - #67
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Format discovery responses like a real device in MIM requester#67tovitch wants to merge 1 commit into
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The Second Screen app silently discards the emulated device's SRCH response, so "PlayActor" never shows up in the app and the PS4 credential flow cannot complete (dhleong#25, dhleong#59). Compared byte-for-byte with a real console's response, the emulated one had three differences: - the status line was formatted like a request ("HTTP/1.1 620 Server Standby * HTTP/1.1" instead of the bare status line) - no system-version field - host-request-port pointed to the UDP wake port (987) instead of the TCP second-screen port (997) that real consoles advertise Responding exactly like a real device makes the app list the emulated device again; verified end-to-end against the current iOS app and a PS4 on firmware 13.52. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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Jul 20, 2026
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Thanks for taking a look at this 🙏
| formatted += `${key}:${data[key]}\n`; | ||
| } | ||
| } | ||
| return Buffer.from(`${type} * HTTP/1.1\n${formatOutgoingKeys(data)}device-discovery-protocol-version:${version}\n`); |
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I think we can simplify a lot in this PR by borrowing the heuristic I employed in ps4-waker and only append * HTTP/1.1 if type doesn't already include HTTP
| data: { | ||
| "host-id": this.emulatorOptions.hostId, | ||
| "host-name": this.emulatorOptions.hostName, | ||
| "host-request-port": secondScreenRequestPort, |
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Rather than a fixed constant, let's do a similar map lookup based on device.type that we did for the wakePortsByType, above. requestPortsByType perhaps? I would prefer to keep this less tightly coupled to PS4 specifics.
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| await new Promise(resolve => { setImmediate(resolve); }); | ||
| await new Promise(resolve => { setImmediate(resolve); }); |
| netFactory.onMessage!({ | ||
| type: "SRCH", | ||
| sender: appSender, | ||
| } as unknown as IDiscoveryMessage); |
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Any chance we can just fill out the other couple of properties of IDiscoveryMessage rather than hard cast?
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Problem
When running
playactor loginagainst a PS4, the emulated "PlayActor" device never shows up in the PS4 Second Screen app, so the credential flow can never complete. This is the issue reported in #25 and #59.Root cause
The MIM requester's SRCH response goes through
formatDiscoveryMessage, which formats requests. Comparing the emulated response byte-for-byte with a real console's response to the same SRCH probe:Real PS4 (firmware 13.52):
Emulated device (current main):
Three differences:
* HTTP/1.1, as if it were a request.system-versionfield.host-request-portadvertises the UDP wake port (987) instead of the TCP second-screen port (997) that real consoles advertise.The current Second Screen app (tested on iOS) silently discards this response, so the emulated device never appears in its device list.
Fix
formatDiscoveryResponsetoprotocol.ts: same outgoing-key filtering, but the first line is the bare status line, like a real device sends.host-request-port:997and borrowing thesystem-versionof the device we are requesting credentials for.Verified end-to-end: with this change the Second Screen app lists "PlayActor", taps through, and the credential exchange + device registration on the console complete successfully.
Fixes #25
Fixes #59
🤖 Generated with Claude Code