test pact-go verifications on alpine

[YOU54F]

Problem

pact-go v2 verifications fail on linux musl implementations (tested on Alpine)

Investigation

Add simple verification test to isolate pact-go's implementation, and the underlying libpact_ffi calls via cgo / ebitengine/purego

Test implementations

• pact-go
• libpact_ffi native calls via cgo CGO_ENABLED=1
• libpact_ffi native calls via ebitengine/purego CGO_ENABLED=0

Test combinations

• go versions
  • 1.22
  • 1.23
• cgo
  • on
  • off
• variant
  • alpine
  • debian
• implementation
  • pact-go
  • cgo when CGO_ENABLED=1
  • ebitengine/purego when CGO_ENABLED=0

Test Results

1. libpact_ffi native calls via cgo or ebitengine/purego both pass in our simple test on alpine linux
2. pact-go fails in our simple test on alpine linux

Hypothesis - pact-go creates a http proxy, which sits in-between pact-reference and the SUT. The main use case for this is request filters (modifications on requests from the Pact Verifier and the SUT). The error must reside somewhere in that code.

Next steps

1. modify pact-go to not start a proxy, and retest.
2. If the above step passes, look into proxy code.

[YOU54F]

Using an alpine container, I've been doing some debugging.

The following is from testing against this code

https://github.com/YOU54F/pact-reference/tree/feat/purego

add https://github.com/ianlancetaylor/cgosymbolizer to project

_ "github.com/ianlancetaylor/cgosymbolizer"

apk add golang musl-dev gcc gdb # install deps
go test -v pact/go/native/native -count 1 -c # build test binary
# setup gdb
mkdir -p /root/.config/gdb 
echo "set auto-load safe-path /" > /root/.config/gdb/gdbinit 
# run test under gdb
PACT_PROVIDER_DIR=./native/pacts_http gdb -ex run --args ./native.test -test.count=5

Seg fault shown

(gdb) run
Starting program: /home/go/native.test -test.count=5
warning: Error disabling address space randomization: Operation not permitted
[New LWP 6326]
[New LWP 6327]
[New LWP 6328]
[New LWP 6329]
[New LWP 6330]
[New LWP 6331]
[New LWP 6332]
[New LWP 6333]
[New LWP 6334]
[New LWP 6335]
[New LWP 6336]
[New LWP 6337]
[New LWP 6338]
[New LWP 6339]
[New LWP 6340]

Verifying a pact between c1 and p1

  A POST request to create book (0s loading, 9ms verification)
     Given No book fixtures required
      Request Failed - error sending request for url (http://localhost:8000/api/books)


Failures:

1) Verifying a pact between c1 and p1 Given No book fixtures required - A POST request to create book - error sending request for url (http://localhost:8000/api/books)


There were 1 pact failures

Result is not 0: 1
Thread 4 "native.test" received signal SIGSEGV, Segmentation fault.
[Switching to LWP 6328]
0x0000ffff7e8b9654 in pact_ffi::verifier::handle::{impl#0}::execute::{async_block#1} () at pact_ffi/src/verifier/handle.rs:289
289         match RUNTIME.block_on(LOG_ID.scope(format!("verify:{}", self.provider.name), async {
(gdb) bt
#0  0x0000ffff7e8b9654 in pact_ffi::verifier::handle::{impl#0}::execute::{async_block#1} () at pact_ffi/src/verifier/handle.rs:289
#1  0x0000ffff7e7aa88c in tokio::task::task_local::{impl#4}::poll::{closure#0}<alloc::string::String, pact_ffi::verifier::handle::{impl#0}::execute::{async_block_env#1}> () at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.42.0/src/task/task_local.rs:391
#2  0x0000ffff7e7ab518 in tokio::task::task_local::LocalKey<alloc::string::String>::scope_inner<alloc::string::String, tokio::task::task_local::{impl#4}::poll::{closure_env#0}<alloc::string::String, pact_ffi::verifier::handle::{impl#0}::execute::{async_block_env#1}>, core::option::Option<core::task::poll::Poll<core::result::Result<pact_verifier::verification_result::VerificationExecutionResult, anyhow::Error>>>> (
    self=0xffff80a4ad08 <pact_matching::logging::LOG_ID>, slot=0xffff36353ed8, f=...)
    at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.42.0/src/task/task_local.rs:217
#3  0x0000ffff7e7aa32c in tokio::task::task_local::{impl#4}::poll<alloc::string::String, pact_ffi::verifier::handle::{impl#0}::execute::{async_block_env#1}> (self=..., cx=0xffff377cad10) at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.42.0/src/task/task_local.rs:387
#4  0x0000ffff7e660f18 in core::future::future::{impl#1}::poll<alloc::boxed::Box<tokio::task::task_local::TaskLocalFuture<alloc::string::String, pact_ffi::verifier::handle::{impl#0}::execute::{async_block_env#1}>, alloc::alloc::Global>> (self=..., cx=0xffff377cad10)
    at /rustc/90b35a6239c3d8bdabc530a6a0816f7ff89a0aaf/library/core/src/future/future.rs:123
#5  0x0000ffff7e484fc8 in tokio::runtime::park::{impl#4}::block_on::{closure#0}<core::pin::Pin<alloc::boxed::Box<tokio::task::task_local::TaskLocalFuture<alloc::string::String, pact_ffi::verifier::handle::{impl#0}::execute::{async_block_env#1}>, alloc::alloc::Global>>> ()
    at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.42.0/src/runtime/park.rs:281
#6  0x0000ffff7e4844a8 in tokio::runtime::coop::with_budget<core::task::poll::Poll<core::result::Result<pact_verifier::verification_result::VerificationExecutionResult, anyhow::Error>>, tokio::runtime::park::{impl#4}::block_on::{closure_env#0}<core::pin::Pin<alloc::boxed::Box<tokio::task::task_local::TaskLocalFuture<alloc::string::String, pact_ffi::verifier::handle::{impl#0}::execute::{async_block_env#1}>, alloc::alloc::Global>>>> (budget=..., f=...)
    at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.42.0/src/runtime/coop.rs:107
#7  tokio::runtime::coop::budget<core::task::poll::Poll<core::result::Result<pact_verifier::verification_result::VerificationExecutionResult, anyhow::Error>>, tokio::runtime::park::{impl#4}::block_on::{closure_env#0}<core::pin::Pin<alloc::boxed::Box<tokio::task::task_local::TaskLocalFuture<alloc::string::String, pact_ffi::verifier::handle::{impl#0}::execute::{async_block_env#1}>, alloc::alloc::Global>>>> (f=...)
    at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.42.0/src/runtime/coop.rs:73
#8  tokio::runtime::park::CachedParkThread::block_on<core::pin::Pin<alloc::boxed::Box<tokio::task::task_local::TaskLocalFuture<alloc::string::String, pact_ffi::verifier::handle::{impl#0}::execute::{async_block_env#1}>, alloc::alloc::Global>>> (self=0xffff377caefe, f=...)
    at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.42.0/src/runtime/park.rs:281
#9  0x0000ffff7e74e1e4 in tokio::runtime::context::blocking::BlockingRegionGuard::block_on<core::pin::Pin<alloc::boxed::Box<tokio::task::task_local::TaskLocalFuture<alloc::string::String, pact_ffi::verifier::handle::{impl#0}::execute::{async_block_env#1}>, alloc::alloc::Global>>> (self=0xffff377cb060, f=...)
    at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.42.0/src/runtime/context/blocking.rs:66
#10 0x0000ffff7e80c2f4 in tokio::runtime::scheduler::multi_thread::{impl#0}::block_on::{closure#0}<core::pin::Pin<alloc::boxed::Box<tokio::task::task_local::TaskLocalFuture<alloc::string::String, pact_ffi::verifier::handle::{impl#0}::execute::{async_block_env#1}>, alloc::alloc::Global>>> (
--Type <RET> for more, q to quit, c to continue without paging--
    blocking=0xffff377cb060) at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.42.0/src/runtime/scheduler/multi_thread/mod.rs:87
#11 0x0000ffff7e6c2d40 in tokio::runtime::context::runtime::enter_runtime<tokio::runtime::scheduler::multi_thread::{impl#0}::block_on::{closure_env#0}<core::pin::Pin<alloc::boxed::Box<tokio::task::task_local::TaskLocalFuture<alloc::string::String, pact_ffi::verifier::handle::{impl#0}::execute::{async_block_env#1}>, alloc::alloc::Global>>>, core::result::Result<pact_verifier::verification_result::VerificationExecutionResult, anyhow::Error>> (
    handle=0xffff80b5ab18 <<pact_ffi::RUNTIME as core::ops::deref::Deref>::deref::__stability::LAZY+48>, allow_block_in_place=true, f=...)
    at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.42.0/src/runtime/context/runtime.rs:65
#12 0x0000ffff7e80be88 in tokio::runtime::scheduler::multi_thread::MultiThread::block_on<core::pin::Pin<alloc::boxed::Box<tokio::task::task_local::TaskLocalFuture<alloc::string::String, pact_ffi::verifier::handle::{impl#0}::execute::{async_block_env#1}>, alloc::alloc::Global>>> (
    self=0xffff80b5aaf0 <<pact_ffi::RUNTIME as core::ops::deref::Deref>::deref::__stability::LAZY+8>, 
    handle=0xffff80b5ab18 <<pact_ffi::RUNTIME as core::ops::deref::Deref>::deref::__stability::LAZY+48>, future=...)
    at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.42.0/src/runtime/scheduler/multi_thread/mod.rs:86
#13 0x0000ffff7e9354c4 in tokio::runtime::runtime::Runtime::block_on_inner<core::pin::Pin<alloc::boxed::Box<tokio::task::task_local::TaskLocalFuture<alloc::string::String, pact_ffi::verifier::handle::{impl#0}::execute::{async_block_env#1}>, alloc::alloc::Global>>> (
    self=0xffff80b5aae8 <<pact_ffi::RUNTIME as core::ops::deref::Deref>::deref::__stability::LAZY>, future=...)
    at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.42.0/src/runtime/runtime.rs:370
#14 0x0000ffff7e935754 in tokio::runtime::runtime::Runtime::block_on<tokio::task::task_local::TaskLocalFuture<alloc::string::String, pact_ffi::verifier::handle::{impl#0}::execute::{async_block_env#1}>> (self=0xffff80b5aae8 <<pact_ffi::RUNTIME as core::ops::deref::Deref>::deref::__stability::LAZY>, 
    future=...) at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.42.0/src/runtime/runtime.rs:340
#15 0x0000ffff7e55bb9c in pact_ffi::verifier::handle::VerifierHandle::execute (self=0xffff80c713c0) at pact_ffi/src/verifier/handle.rs:289
#16 0x0000ffff7e854aac in pact_ffi::verifier::pactffi_verifier_execute::{closure#0} () at pact_ffi/src/verifier/mod.rs:645
#17 0x0000ffff7e6e23d0 in std::panicking::try::do_call<pact_ffi::verifier::pactffi_verifier_execute::{closure_env#0}, core::result::Result<i32, anyhow::Error>> (data=0xffff377db1f0) at /rustc/90b35a6239c3d8bdabc530a6a0816f7ff89a0aaf/library/std/src/panicking.rs:557
#18 0x0000ffff7e518974 in __rust_try () from /home/rust/target/debug/libpact_ffi.so
#19 0x0000ffff7e51268c in std::panicking::try<core::result::Result<i32, anyhow::Error>, pact_ffi::verifier::pactffi_verifier_execute::{closure_env#0}> (
    f=...) at /rustc/90b35a6239c3d8bdabc530a6a0816f7ff89a0aaf/library/std/src/panicking.rs:520
#20 std::panic::catch_unwind<pact_ffi::verifier::pactffi_verifier_execute::{closure_env#0}, core::result::Result<i32, anyhow::Error>> (f=...)
    at /rustc/90b35a6239c3d8bdabc530a6a0816f7ff89a0aaf/library/std/src/panic.rs:358
#21 0x0000ffff7e75f914 in pact_ffi::error::panic::catch_panic<i32, pact_ffi::verifier::pactffi_verifier_execute::{closure_env#0}> (f=...)
    at pact_ffi/src/error/panic.rs:20
#22 0x0000ffff7e479400 in pact_ffi::verifier::pactffi_verifier_execute (handle=0xffff80c713c0) at pact_ffi/src/util/ffi.rs:23
#23 0x0000000000515acc in _cgo_e74e85c454e1_Cfunc_pactffi_verifier_execute (v=0x4000062e78) at /tmp/go-build/cgo-gcc-prolog:249
#24 0x00000000004772bc in runtime.asmcgocall () at /usr/lib/go/src/runtime/asm_arm64.s:1000
--Type <RET> for more, q to quit, c to continue without paging--

I'll create a minimal repro in a docker container using the pact-ref source, and raise it with the go team and see if they can offer any pointers.