# nvfetcher

[![Hackage](https://img.shields.io/hackage/v/nvfetcher.svg?logo=haskell)](https://hackage.haskell.org/package/nvfetcher)
[![MIT license](https://img.shields.io/badge/license-MIT-blue.svg)](LICENSE)
[![nix](https://github.com/berberman/nvfetcher/actions/workflows/nix.yml/badge.svg)](https://github.com/berberman/nvfetcher/actions/workflows/nix.yml)

nvfetcher is a tool to automate nix package updates. It's built on top of [shake](https://www.shakebuild.com/),
integrating [nvchecker](https://github.com/lilydjwg/nvchecker).
nvfetcher cli program accepts a TOML file as config, which defines a set of package sources to run.

## Overview

For example, feeding the following configuration to`nvfetcher`:

```toml
# nvfetcher.toml
[feeluown]
src.pypi = "feeluown"
fetch.pypi = "feeluown"
```

it will create `_sources/generated.nix`:

```nix
{ fetchgit, fetchurl, fetchFromGitHub }:
{
  feeluown = {
    pname = "feeluown";
    version = "3.8.2";
    src = fetchurl {
      url = "https://pypi.io/packages/source/f/feeluown/feeluown-3.8.2.tar.gz";
      sha256 = "sha256-V2yzpkmjRkipZOvQGB2mYRhiiEly6QPrTOMJ7BmyWBQ=";
    };
  };
}
```

and `_sources/generated.json`:

```json
{
  "feeluown": {
    "pinned": false,
    "cargoLocks": null,
    "name": "feeluown-core",
    "version": "3.8.2",
    "passthru": null,
    "src": {
      "url": "https://pypi.io/packages/source/f/feeluown/feeluown-3.8.2.tar.gz",
      "name": null,
      "type": "url",
      "sha256": "sha256-V2yzpkmjRkipZOvQGB2mYRhiiEly6QPrTOMJ7BmyWBQ="
    },
    "extract": null,
    "rustGitDeps": null
  }
}
```

We tell nvfetcher how to get the latest version number of packages and how to fetch their sources given version numbers,
and nvfetcher will help us keep their version and prefetched SHA256 sums up-to-date, producing ready-to-use nix expressions in `_sources/generated.nix`.
Nvfetcher reads `generated.json` to produce version change message, such as `feeluown: 3.8.1 → 3.8.2`.
We always check versions of packages during each run, but only do prefetch and further operations when needed.

### Live examples

How to use the generated sources file? Here are several examples:

- My [flakes repo](https://github.com/berberman/flakes)

- Nick Cao's [flakes repo](https://gitlab.com/NickCao/flakes/-/tree/master/pkgs)

## Installation

`nvfetcher` package is available in [nixpkgs](https://github.com/NixOS/nixpkgs), so you can try it with:

```
$ nix-shell -p nvfetcher
```

This repo also has flakes support:

```
$ nix run github:berberman/nvfetcher
```

To use it as a Haskell library, the package is available on [Hackage](https://hackage.haskell.org/package/nvfetcher).
If you want to use the Haskell library from flakes, there is also a shell `ghcWithNvfetcher`:

```
$ nix develop github:berberman/nvfetcher#ghcWithNvfetcher
$ runghc Main.hs
```

where you can define packages in `Main.hs`. See [Haskell library](#Haskell-library) for details.

## Usage

Basically, there are two ways to use nvfetcher, where the difference is how we provide package sources definitions to it.

### CLI

To run nvfetcher as a CLI program, you'll need to provide package sources defined in TOML.

```
Usage: nvfetcher [--version] [--help] [-o|--build-dir DIR] [--commit-changes]
                 [-l|--changelog FILE] [-j NUM] [-r|--retry NUM] [-t|--timing]
                 [-v|--verbose] [-f|--filter REGEX] [-k|--keyfile FILE] [TARGET]
                 [-c|--config FILE]
  generate nix sources expr for the latest version of packages

Available options:
  --version                Show version
  --help                   Show this help text
  -o,--build-dir DIR       Directory that nvfetcher puts artifacts to
                           (default: "_sources")
  --commit-changes         `git commit` build dir with version changes as commit
                           message
  -l,--changelog FILE      Dump version changes to a file
  -j NUM                   Number of threads (0: detected number of processors)
                           (default: 0)
  -r,--retry NUM           Times to retry of some rules (nvchecker, prefetch,
                           nix-build, etc.) (default: 3)
  -t,--timing              Show build time
  -v,--verbose             Verbose mode
  -f,--filter REGEX        Regex to filter packages to be updated
  -k,--keyfile FILE        Nvchecker keyfile
  TARGET                   Two targets are available: 1.build 2.clean
                           (default: build)
  -c,--config FILE         Path to nvfetcher TOML config
                           (default: "nvfetcher.toml")
```

Each _package_ corresponds to a TOML table, whose name is encoded as table key, with
two required fields and three optional fields in each table.
You can find an example of the configuration file, see [`nvfetcher_example.toml`](nvfetcher_example.toml).

### Keyfile

You can specify nvchecker keyfile via command line option.
For the format of this file, please refer to [nvchecker documentation](https://nvchecker.readthedocs.io/en/latest/usage.html#configuration-table).

#### Nvchecker

Version source -- how do we track upstream version updates?

- `src.github = owner/repo` - the latest github release
- `src.github_tag = owner/repo` - the max github tag, usually used with list options (see below)
- `src.pypi = pypi_name` - the latest pypi release
- `src.git = git_url` (and an optional `src.branch = git_branch`) - **the latest commit** of a repo
- `src.archpkg = archlinux_pkg_name` -- the latest version of an archlinux package
- `src.aur = aur_pkg_name` -- the latest version of an aur package
- `src.manual = v` -- a fixed version, which never updates
- `src.repology = project:repo` -- the latest version from repology
- `src.webpage = web_url` and `src.regex` -- a string in webpage that matches with regex
- `src.httpheader = request_url` and `src.regex` -- a string in http header that matches with regex
- `src.openvsx = publisher.ext_name` -- the latest version of a vscode extension from open vsx
- `src.vsmarketplace = publisher.ext_name` -- the latest version of a vscode extension from vscode marketplace
- `src.cmd = cmd` -- the version from a shell command (e.g. `echo Meow`)
- `src.container = owner/name` - the latest tag of a container from the Docker registry

Optional list options for some version sources (`src.github_tag`, `src.webpage`, and `src.httpheader` and `src.container`),
see the corresponding [nvchecker documentation](https://nvchecker.readthedocs.io/en/latest/usage.html#list-options) for details.

- `src.include_regex`
- `src.exclude_regex`
- `src.sort_version_key`
- `src.ignored`

Optional global options for all kinds of version sources,
see the corresponding [nvchecker documentation](https://nvchecker.readthedocs.io/en/latest/usage.html#global-options) for details. You can tweak obtained version number using this option, e.g. stripping the prefix `v` or transforming the result by regex.

- `src.prefix`
- `src.from_pattern`
- `src.to_pattern`

#### Nix fetcher

How do we fetch the package source if we have the target version number?
`$ver` is available in string, which will be set to the result of nvchecker.

- `fetch.github = owner/repo`
- `fetch.pypi = pypi_name`
- `fetch.git = git_url`
- `fetch.url = url`
- `fetch.openvsx = publisher.ext_name`
- `fetch.vsmarketplace = publisher.ext_name`
- `fetch.tarball = tarball_url`
- `fetch.docker = owner/name`

Optional `nix-prefetch fetchgit` config, which make sense only when the fetcher equals to `fetch.github` or `fetch.git`.
They can exist simultaneously.

- `git.deepClone`
- `git.fetchSubmodules`
- `git.leaveDotGit`

Optional config for `fetch.docker`/`dockerTools.pullImage`:

- `docker.os`
- `docker.arch`
- `docker.finalImageName`
- `docker.finalImageTag`
- `docker.tlsVerify`

#### Extract src

Optional _extract src_ config, files are extracted into build directory, and then read by `readFile` in generated nix expr.

- `extract = [ "file_1", "file_2", ...]` - file paths are relative to the source root

#### Rust support

`rustPlatform.buildRustPackage` now accepts an attribute [`cargoLock`](https://github.com/NixOS/nixpkgs/blob/master/doc/languages-frameworks/rust.section.md#importing-a-cargolock-file) to vendor dependencies from `Cargo.lock`,
so we can use this instead of TOFU `cargoSha256` for Rust packaging. `nvfetcher` supports automating this process,
extracting the lock file to build and calculating `cargoLock.outputHashes`, as long as you set the config.
There can be many lock files in one source.

- `cargo_locks = [ "cargo_lock_path_1", "cargo_lock_path_2", ...]` - relative to the source root

#### Passthru

_passthru_ config, an additional set of attrs to be generated.

- `passthru = { k1 = "v1", k2 = "v2", ... }`

Note: currently the values can only be strings

#### Pinned

If a package is pinned, we call nvchecker to check the new version iff there's no existing version.

- `pinned = true`

#### Git commit date

If the version source of a package is `git`, nvfetcher can finds out the commit date of this revision,
in the format of `%Y-%m-%d` by default. You can provide your own [`strftime`](https://strftime.org/) format:

- `git.date_format = "strftime_format"`

#### Force fetching

Always fetch the package, even if its version (nvchecker output) doesn't change.
This is useful when the file to be downloaded cannot not be determined by the url.

- `fetch.force = true`

> Note: In such case, nvfetcher will not produce a version change log, since the version doesn't change at all.
> Only sha256 in generated files will be updated.

### Haskell library

nvfetcher itself is a Haskell library as well, whereas the CLI program is just a trivial wrapper of the library.
You can create a Haskell program depending on it directly, by using the `runNvFetcher` entry point.
In this case, we can define packages in Haskell language, getting rid of TOML constraints.

You can find an example of using nvfetcher in the library way, see [`Main_example.hs`](Main_example.hs).

## Documentation

For details of the library, documentation of released versions is available on [Hackage](https://hackage.haskell.org/package/nvfetcher),
and of master is on our [github pages](https://nvfetcher.berberman.space).

## Contributing

Issues and PRs are always welcome. **\_(:з」∠)\_**

Building from source:

```
$ git clone https://github.com/berberman/nvfetcher
$ nix develop
$ cabal update
$ cabal build
```