ETXTBSY on execute_install()

[Kiskae]

Recently been getting run failures with an Error: spawn ETXTBSY error.

Tracking down the source appears to show

nix-installer-action/src/main.ts

Lines 268 to 270 in 721f94f

	const spawned = spawn(`${binary_path}`, args, {
	env: merged_env,
	});

failing and causing an uncaught exception to propagate through the action.

This specific failure reminds me of the race condition mentioned in the README of https://github.com/buildbarn/bb-remote-execution - requiring separate processes to handle downloading of an executable and executing that executable.

• To work around os: StartProcess ETXTBSY race on Unix systems golang/go#22315 that effectively prevents multi-threaded processes from writing executables to disk and spawning them. Through this decomposition, bb_worker writes executables to disk, while bb_runner spawns them.

Excerpt from workflow log:

2023-11-02T13:53:48.8844243Z ##[group]Run DeterminateSystems/nix-installer-action@v6
2023-11-02T13:53:48.8844899Z with:
2023-11-02T13:53:48.8845200Z   flakehub: false
2023-11-02T13:53:48.8845821Z   github-token: ***
2023-11-02T13:53:48.8846200Z   modify-profile: true
2023-11-02T13:53:48.8846748Z   reinstall: false
2023-11-02T13:53:48.8847092Z   start-daemon: true
2023-11-02T13:53:48.8847777Z   diagnostic-endpoint: https://install.determinate.systems/nix/diagnostic
2023-11-02T13:53:48.8848606Z   trust-runner-user: true
2023-11-02T13:53:48.8848997Z ##[endgroup]
2023-11-02T13:53:49.0060064Z Fetching binary from https://install.determinate.systems/nix/nix-installer-x86_64-linux?ci=github&correlation=GH-599763b2-1658-467b-abe6-984a90a66e96
2023-11-02T13:53:49.5869054Z Downloaded `nix-installer` to `/tmp/nix-installer-7iB0Nw/nix-installer-x86_64-linux`
2023-11-02T13:53:49.5897493Z Execution environment: {
2023-11-02T13:53:49.5903883Z     "NIX_INSTALLER_NO_CONFIRM": "true",
2023-11-02T13:53:49.5904829Z     "NIX_INSTALLER_DIAGNOSTIC_ATTRIBUTION": "GH-599763b2-1658-467b-abe6-984a90a66e96",
2023-11-02T13:53:49.5905559Z     "NIX_INSTALLER_MODIFY_PROFILE": "true",
2023-11-02T13:53:49.5906364Z     "NIX_INSTALLER_DIAGNOSTIC_ENDPOINT": "https://install.determinate.systems/nix/diagnostic",
2023-11-02T13:53:49.5907140Z     "NIX_INSTALLER_START_DAEMON": "true",
2023-11-02T13:53:49.5909417Z     "NIX_INSTALLER_EXTRA_CONF": "access-tokens = github.com=***\ntrusted-users = root runner\n"
2023-11-02T13:53:49.5910164Z }
2023-11-02T13:53:49.6049345Z ##[error]Error: spawn ETXTBSY
2023-11-02T13:53:49.6219046Z Post job cleanup.

[Hoverbear]

Thanks for the report!

@colemickens prepared a possible fix with #47, I'll be cutting that this morning.

[Kiskae]

I'm not sure how useful it would be, but perhaps the error should be propagated instead of going through the uncaught exception handler?

nix-installer-action/src/main.ts

Lines 288 to 290 in 721f94f

	const exit_code: number = await new Promise((resolve, _reject) => {
	spawned.on("close", resolve);
	});

const exit_code: number = await new Promise((resolve, reject) => {
  spawned.on("close", resolve);
  spawned.on("error", reject);
});

EDIT: might need to replace close with exit, since close gets emitted after error or exit

[Kiskae]

Haven't seen the error since updating the action, will reopen if it shows up again.

[Hoverbear]

Great!