apns-simulator (archived)

This repository is archived and unmaintained. It is kept for history only.

It simulates APNs over the binary provider protocol, which Apple switched off on 31 March 2021. Nothing it accepts on the wire will reach a device, and nothing that talks to real APNs today can be tested against it. The last change here was in 2018; there is no go.mod, so it predates Go modules and will not build with a modern toolchain without one.

srv/apns/apnstest in uniqush-push is an APNs simulator for the HTTP/2 provider API, the one Apple still serves. It is a Go package rather than a separate process, so a test starts it in-process on a random port:

server := apnstest.NewServer()
defer server.Close()

// Point the provider at server.URL(), then assert on what arrived.
for _, r := range server.Requests() { ... }
for _, v := range server.Violations() { ... }

It answers what Apple documents, and it rejects what Apple rejects — a missing apns-push-type, a background push at priority 10, a topic header sent twice under two spellings — recording each as a conformance violation, so a failing test says which rule was broken rather than only that the push failed. It also validates .p8 provider tokens, models the token refresh interval with an injectable clock, and counts open connections. It does not deliver to a device and never authenticates a client certificate.

This closes the two open issues that were filed here:

• #2, scriptable library for integration testing — SetResponse makes the response depend on the device token, Requests() is the call log, and ActiveConnections() reports connection lifecycle.
• #3, HTTP/2 simulation with a local certificate — apnstest.NewServer generates a self-signed certificate, and WriteCACert writes it out so the client under test can verify the chain rather than skip verification.

It lives in uniqush-push rather than here on purpose. The simulator's value is that it disagrees with uniqush when uniqush is wrong, so it is developed in the same commit as the behaviour it pins; splitting it across two repositories would put a release boundary in the middle of that loop. Being in-tree does not make it private — it is an ordinary importable package:

import "github.com/uniqush/uniqush-push/srv/apns/apnstest"

If you need a standalone simulator process — because the client you are testing is not written in Go — open an issue on uniqush-push. Wrapping apnstest in a command is small; it has not been done because no one has asked.