# Changelog

All notable changes to this project will be documented in this file.

The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).

## [0.7.5] - 2020-11-27

### Fixed

 - GHC 8.10.2 compatibility for NixOS unstable / NixOS 21.03

 - Build with cachix 0.5.1. Write token support is not included due to a break configuration semantics. It will be available in >= 0.8.

### Changed

 - The in-repo expressions have upgraded their dependency to NixOS 20.09

 - Agent will now use `HERCULES_CI_API_BASE_URL` over `HERCULES_API_BASE_URL` if set.

 - Temporarily switch to cabal tooling due to breakage. `master` continues to be stack-based.

## [0.7.4] - 2020-08-25

### Fixed

 - Paths that are missing from the binary cache will be rebuilt. This affected
   agent 0.7 - 0.7.3 users with trusted user optimizations turned on, which is
   the default when using the NixOS or nix-darwin modules.

 - Prevent states where no progress can be made. One caused by a potential buildup
   of batched messages that may not fit within the timeout interval; the other
   a receive operation without a timeout during the initial socket handshake.

 - The log socket will remain open instead of reconnecting unnecessarily.

 - Add a safety measure to prevent unintended increases in workload in case
   Nix sees an opportunity for concurrency that was not intended by Hercules CI.

### Changed

 - The NixOS module in the hercules-ci-agent repo now disables the upcoming
   module that is packaged upstream with NixOS.

   The upstream module will configure fewer things for you, to be in line with
   normal NixOS expectations. Notably, it does not configure automatic garbage
   collection and it does not preconfigure NixOps keys deployment.

   The configuration interface will remain unchanged for `0.7` but `0.8` will
   match the upstream interface.

## [0.7.3] - 2020-07-18

### Added

 - Evaluation log

 - Configurable log level via config file or `extraOptions`

### Changed

 - Default log level is `InfoS` rather than `DebugS`

## [0.7.2] - 2020-06-18

### Changed

 - cachix: 0.3.7 -> 0.3.8. Improves reliability through better retries and improves error reporting

## [0.7.1] - 2020-06-17

### Added

 - Push to any nix store, including S3, using the `NixCache` kind in `binary-caches.json`

### Changed

 - Switch to Nixpkgs 20.03

 - Environment variables are now passed on to evaluation and build by default. This allows configuration to be passed to Nix without intervention from hercules-ci-agent.

 - `trusted-user` is not a requirement and is configured automatically when using the NixOS module or nix-darwin module.

### Fixed

 - Agent will now reset its connection with hercules-ci.com when pings are not acknowledged in time.

 - Prevent running out of file descriptors by increasing the soft limit if possible.

## [0.7.0] - 2020-05-05

### Known issues

 - Agent process user must be in `trusted-users`. This is the case with the NixOS and nix-darwin module. Doing so is recommended for ease of use and performance but should not be a requirement.

### Added

 - Jobs can be cancelled

 - Build logs are streamed in realtime

 - The build log now has timestamps and color

 - Distributed builds performance has improved by fetching fewer derivations

### Fixed

 - Extra nix options were not passed to the build process

## [0.6.6] - 2020-03-16

### Fixed

 - NixOS, nix-darwin modules: check the `nix-daemon` source and add option to patch an in-memory cache expiry issue
   causing errors in build clusters (of more than 1 machine). The module asks for confirmation.

 - **Manual action:** if you are not using the provided module and you run the agent on
   more than one machine, and you use `nix-daemon`, to fix above issue, you need to:
    - either upgrade your system's Nix to a recent `master` or version 2.4.0 when released,
    - or apply this patch to your system's Nix installation: https://github.com/NixOS/nix/pull/3405

 - Cachix: 0.3.5 -> [0.3.7](https://github.com/cachix/cachix/blob/master/cachix/CHANGELOG.md#037---2020-03-12) to prevent uploading bad NARs in rare cases.

## [0.6.5] - 2020-03-07

### Fixed

 - Work around a systemd behavior where it didn't restart the unit

### Added

 - `--test-configuration` flag to validate the configuration without actually running the agent.

## [0.6.4] - 2020-03-06

### Fixed

 - Fix a bug blocking evaluation when a store path is removed from cache or cache configuration is changed.

### Added

 - Cached builds to speed up `aarch64-linux` agent deployments.

### [0.6.3] - 2020-02-19

### Fixed

 - Fix a concurrency problem causing not all evaluation events to be written to server when evaluation fails.

 - Fix evaluation errors triggered by build outputs go missing from cache, by requesting a forced rebuild.

 - Fix blocked shutdown on NixOS, fix agent status in dashboard, by stopping agent before network shutdown #195.

 - Fix upload of large outputs by using the correct http client manager for Cachix, removing a timeout.

### Changed

 - Agent will now try to verify that the nix-daemon has narinfo-cache-negative-ttl = 0. This is required for correct operation.

### [0.6.2] - 2020-01-30

### Fixed

 - Update cachix to support the API change for the new CDN. This update is
   required for uploading sources and compressed outputs over 100MB in size.
   Please update.

### [0.6.1] - 2019-11-06

### Fixed

 - Fix token leak to system log when reporting an HTTP exception. This was introduced by a library upgrade.
   This was discovered after tagging 0.6.0 but before the release was
   announced and before moving of the `stable` branch.
   Only users of the `hercules-ci-agent` `master` branch and the unannounced
   tag were exposed to this leak.
   We recommend to follow the `stable` branch.

 - Temporarily revert a Nix GC configuration change that might cause problems
   until agent gc root behavior is improved.

### [0.6.0] - 2019-11-04

### Changed

 - Switch to Nix 2.3 and NixOS 19.09. *You should update your deployment to reflect the NixOS upgrade*, unless you're using terraform or nix-darwin, where it's automatic.
 - Increased parallellism during push to cachix
 - Switch to NixOS 19.09
 - Enable min-free/max-free Nix GC

### Fixed

 - Transient errors during source code fetching are now retried
 - Fixed a bug related to narinfo caching in the context of IFD
 - Fixed an exception when the root of ci.nix is a list, although lists are unsupported

## [0.5.0] - 2019-10-01

### Added

- Now deployable with [terraform-hercules-ci](https://github.com/hercules-ci/terraform-hercules-ci)

### Changed

- The `binary-caches.json` file can now be deployed like any other confidential file. Its contents are not required at module evaluation time any more.

- The `services.hercules-ci-agent.binaryCachesFile` option has been removed.

  **NixOps users**: rename to `deployment.keys."binary-caches.json".file`

  **Others**: remove your `binaryCachesFile` value. Make sure `binary-caches.json` is deployed.

- The `binary-caches.json` file is now required. The empty object `{}` is a
  valid file, but we highly recommend to configure a cache.


### Fixed

 - The agent will now actually auto-restart when the secrets files change.


## [0.4.0] - 2019-08-30

### Added

- Support for import-from-derivation. See https://blog.hercules-ci.com/2019/08/30/native-support-for-import-for-derivation/ for details.

### Changed


- Report build failures and technical errors (misconfigurations, etc) separately

- Remove HerculesScribe

- Worker now uses structured logging (including worker pid, etc)

### Fixed

- Disable parallel GHC GC to improve runtime performance

- Bump Cachix to fix a few bugs (errors with too many derivations, performance fixes, etc.)

 - Modern BoehmGC initial settings for Nix memory limits 

## [0.3.2] - 2019-08-11

### Fixed

- Deploying the agent from different system (darwin to linux) resulted into
  using the wrong executable


## [0.3.1] - 2019-08-07

### Changed

- Emit a log when evaluator starts to push to cachix

- Increase attribute limit to 50k

- Pin nixpkgs commit and speed up compilation via https://hercules-ci.cachix.org


### Fixed

- Possible exception during evaluation was not propagated,
  resulting into lack of retries

- #8: Refresh agent session on cluster join token change

- Fix segfault on involved IFD project (remove a finalizer)

- Cachix: fix a crash with a lot of attributes (when determining closure graph)

## [0.3.0] - 2019-07-05

### Changed

- Configuration of the agent is now done via `--config agent.toml`
  so all command line arguments were removed.

  See https://docs.hercules-ci.com/#agent-configuration-file

- NixOS-based deployments now require `enable`.

      services.hercules-ci-agent.enable = true;

- All files are placed/expected in new locations that by default derive
  from the `baseDirectory` option in the `agent.toml` file.

  You may remove `~/.hercules-ci-agent` and `~/.local/share/hercules-ci-agent` after upgrading.

### Fixed

- Added retries to status reporting to fix potential
  inconsistencies on the service

### Added

- Added Cachix support, for multi-agent and multi-platform support

- Report derivation outputs with their size and hashes

- Added Darwin support via nix-darwin

- Support `requiredFeatures` attribute on derivations

- Hello and hearthbeat protocol, which will allow the
  service to be aware of how the agent is configured and
  when it's online.

## [0.2] - 2019-05-14

- use [gitignore] instead of [nix-gitignore]
- fix build on Darwin
- limit internal concurrency to max eight OS threads for beefier machines
- show version on `--help`
- build against NixOS 19.03 as default
- propagate agent information to agent view: Nix version, substituters,
  platform and Nix features

## [0.1.1] - 2019-04-16

### Added

- Support ci.nix or nix/ci.nix along with default.nix

## [0.1.0.0] - 2019-03-28

- Initial release

[0.7.4]: https://github.com/hercules-ci/hercules-ci-agent/compare/hercules-ci-agent-0.7.3...hercules-ci-agent-0.7.4
[0.7.3]: https://github.com/hercules-ci/hercules-ci-agent/compare/hercules-ci-agent-0.7.2...hercules-ci-agent-0.7.3
[0.7.2]: https://github.com/hercules-ci/hercules-ci-agent/compare/hercules-ci-agent-0.7.1...hercules-ci-agent-0.7.2
[0.7.1]: https://github.com/hercules-ci/hercules-ci-agent/compare/hercules-ci-agent-0.6.6...hercules-ci-agent-0.7.1
[0.6.6]: https://github.com/hercules-ci/hercules-ci-agent/compare/hercules-ci-agent-0.6.5...hercules-ci-agent-0.6.6
[0.6.5]: https://github.com/hercules-ci/hercules-ci-agent/compare/hercules-ci-agent-0.6.4...hercules-ci-agent-0.6.5
[0.6.4]: https://github.com/hercules-ci/hercules-ci-agent/compare/hercules-ci-agent-0.6.3...hercules-ci-agent-0.6.4
[0.6.3]: https://github.com/hercules-ci/hercules-ci-agent/compare/hercules-ci-agent-0.6.2...hercules-ci-agent-0.6.3
[0.6.2]: https://github.com/hercules-ci/hercules-ci-agent/compare/hercules-ci-agent-0.6.1...hercules-ci-agent-0.6.2
[0.6.1]: https://github.com/hercules-ci/hercules-ci-agent/compare/hercules-ci-agent-0.6.0...hercules-ci-agent-0.6.1
[0.6.0]: https://github.com/hercules-ci/hercules-ci-agent/compare/hercules-ci-agent-0.5.0...hercules-ci-agent-0.6.0
[0.5.0]: https://github.com/hercules-ci/hercules-ci-agent/compare/hercules-ci-agent-0.4.0...hercules-ci-agent-0.5.0
[0.4.0]: https://github.com/hercules-ci/hercules-ci-agent/compare/hercules-ci-agent-0.3.2...hercules-ci-agent-0.4.0
[0.3.2]: https://github.com/hercules-ci/hercules-ci-agent/compare/hercules-ci-agent-0.3.1...hercules-ci-agent-0.3.2
[0.3.1]: https://github.com/hercules-ci/hercules-ci-agent/compare/hercules-ci-agent-0.3.0...hercules-ci-agent-0.3.1
[0.3.0]: https://github.com/hercules-ci/hercules-ci-agent/compare/hercules-ci-agent-0.2...hercules-ci-agent-0.3.0
[0.2]: https://github.com/hercules-ci/hercules-ci-agent/compare/hercules-ci-agent-0.1.1...hercules-ci-agent-0.2
[0.1.1]: https://github.com/hercules-ci/hercules-ci-agent/compare/hercules-ci-agent-0.1.0.0...hercules-ci-agent-0.1.1
[Unreleased]: https://github.com/hercules-ci/hercules-ci-agent/compare/stable...master
[nix-gitignore]: https://github.com/siers/nix-gitignore
[gitignore]: https://github.com/hercules-ci/gitignore