<p align="center">
<a href="https://github.com/dotenv-linter/dotenv-linter">
<img alt="dotenv-linter"
width="350" height="192"
src="https://raw.githubusercontent.com/dotenv-linter/dotenv-linter/master/logo.svg?sanitize=true">
</a>
</p>
<h2 align="center">
⚡️Lightning-fast linter for <code>.env</code> files. Written in Rust 🦀
</h2>
<p align="center">
<a href="https://github.com/dotenv-linter/dotenv-linter/actions">
<img alt="GitHub Actions" src="https://github.com/dotenv-linter/dotenv-linter/workflows/CI/badge.svg">
</a>
<a href="https://codecov.io/gh/dotenv-linter/dotenv-linter">
<img alt="Coverage Status" src="https://codecov.io/gh/dotenv-linter/dotenv-linter/branch/master/graph/badge.svg">
</a>
<a href="https://github.com/dotenv-linter/dotenv-linter/blob/master/LICENSE">
<img alt="License" src="https://img.shields.io/github/license/dotenv-linter/dotenv-linter">
</a>
<a href="https://github.com/dotenv-linter/dotenv-linter/releases">
<img alt="Releases" src="https://img.shields.io/github/release/dotenv-linter/dotenv-linter">
</a>
</p>
It checks `.env` files for problems that may cause the application to malfunction:
<p>
✅ <a href="#duplicated-key">Duplicated Key</a><br />
✅ <a href="#ending-blank-line">Ending Blank Line</a><br />
✅ <a href="#extra-blank-line">Extra Blank Line</a><br />
✅ <a href="#incorrect-delimiter">Incorrect delimiter</a><br />
✅ <a href="#key-without-value">Key without value</a><br />
✅ <a href="#leading-character">Leading character</a><br />
✅ <a href="#lowercase-key">Lowercase key</a><br />
✅ <a href="#quote-character">Quote character</a><br />
✅ <a href="#space-character">Space character</a><br />
✅ <a href="#trailing-whitespace">Trailing whitespace</a><br />
✅ <a href="#unordered-Key">Unordered Key</a><br />
</p>
The key features:
<p>
⚡️ Lightning-fast because it is written in Rust 🦀<br />
💣 Can be used on any project regardless of the programming language 💥<br />
🚀 Can be integrated with <a href="https://github.com/reviewdog/reviewdog">reviewdog</a> and other CI services (including <a href="https://github.com/dotenv-linter/action-dotenv-linter">GitHub Actions</a>) 🔥
</p>
Articles about dotenv-linter:
* [In English](https://evrone.com/dotenv-linter?utm_source=github&utm_campaign=dotenv-linter)
* [In Russian](https://www.mgrachev.com/2020/04/20/dotenv-linter)
[Dotenv-linter](https://evrone.com/dotenv-linter?utm_source=github&utm_campaign=dotenv-linter) is created & supported by [Evrone](https://evrone.com/?utm_source=github&utm_campaign=dotenv-linter). What else we develop with [Rust](https://evrone.com/rust?utm_source=github&utm_campaign=dotenv-linter).
## 👨💻 Installation
### Binary
```shell script
# Linux
$ curl https://github.com/dotenv-linter/dotenv-linter/releases/download/v2.0.0/dotenv-linter-linux-x86_64.tar.gz -sSfL | tar -xzf -
# Alpine Linux
$ wget https://github.com/dotenv-linter/dotenv-linter/releases/download/v2.0.0/dotenv-linter-alpine-x86_64.tar.gz -O - -q | tar -xzf -
# macOS
$ curl https://github.com/dotenv-linter/dotenv-linter/releases/download/v2.0.0/dotenv-linter-darwin-x86_64.tar.gz -sSfL | tar -xzf -
```
### Homebrew / Linuxbrew
```shell script
$ brew install dotenv-linter/tap/dotenv-linter
```
### Arch Linux / AUR
```shell script
# use your favourite AUR-helper
$ trizen -S dotenv-linter-bin # for the binary distribution
$ trizen -S dotenv-linter-git # for the current master branch
```
### Docker
```shell script
$ docker run --rm -v `pwd`:/app -w /app dotenvlinter/dotenv-linter
```
### Cargo
If you are a **Rust** programmer, you can install `dotenv-linter` via `cargo`:
```shell script
$ cargo install dotenv-linter
```
### GitHub Action
<details>
<summary>Example: <code>.github/workflows/dotenv_linter.yml</code></summary>
```yaml
name: dotenv-linter
on: [pull_request]
jobs:
dotenv-linter:
name: runner / dotenv-linter
runs-on: ubuntu-latest
steps:
- name: Check out code
uses: actions/checkout@v1
- name: dotenv-linter
uses: dotenv-linter/action-dotenv-linter@v1
with:
github_token: ${{ secrets.github_token }}
```
In the example above, [action-dotenv-linter](https://github.com/dotenv-linter/action-dotenv-linter) is used to run `dotenv-linter`.
</details>
### CircleCI
<details>
<summary>Example: <code>.circleci/config.yml</code></summary>
```yaml
version: 2.1
jobs:
dotenv-linter:
docker:
- image: circleci/rust:latest
steps:
- checkout
- run:
name: Run dotenv-linter
command: |
DOTENV_LINTER_VERSION=v2.0.0
wget https://github.com/dotenv-linter/dotenv-linter/releases/download/$DOTENV_LINTER_VERSION/dotenv-linter-alpine-x86_64.tar.gz \
-O - -q | tar -xzf -
./dotenv-linter
```
</details>
## 🚀 Usage
By default, `dotenv-linter` checks all `.env` files in the current directory:
```shell script
$ dotenv-linter
.env:2 DuplicatedKey: The FOO key is duplicated
.env:3 UnorderedKey: The BAR key should go before the FOO key
.env.test:1 LeadingCharacter: Invalid leading character detected
```
To check another directory, just pass its path as an argument. The same approach works if you need to check any files individually:
```shell script
$ dotenv-linter dir1 dir2/.my-env-file
dir1/.env:1 LeadingCharacter: Invalid leading character detected
dir1/.env:3 IncorrectDelimiter: The FOO-BAR key has incorrect delimiter
dir2/.my-env-file:1 LowercaseKey: The bar key should be in uppercase
```
If you need to exclude a file from check, you can use the argument `--exclude FILE_PATH` or its short version `-e FILE_PATH`:
```shell script
$ dotenv-linter --exclude .env.test
.env:2 DuplicatedKey: The FOO key is duplicated
.env:3 UnorderedKey: The BAR key should go before the FOO key
```
If you need to skip some checks, you can use the argument `--skip CHECK_NAME` or its short version `-s CHECK_NAME`:
```shell script
$ dotenv-linter --skip UnorderedKey EndingBlankLine
.env:2 DuplicatedKey: The FOO key is duplicated
```
If you need to view all available checks, you can use the argument `--show-checks`:
```shell script
$ dotenv-linter --show-checks
DuplicatedKey
EndingBlankLine
ExtraBlankLine
IncorrectDelimiter
KeyWithoutValue
LeadingCharacter
LowercaseKey
QuoteCharacter
SpaceCharacter
TrailingWhitespace
UnorderedKey
```
## ✅ Checks
### Duplicated Key
Detects if a key is not unique:
```env
❌ Wrong
FOO=BAR
FOO=BAR
✅ Correct
FOO=BAR
BAR=FOO
```
### Ending Blank Line
Detects if a file doesn't have a blank line at the end:
```env
❌ Wrong
FOO=BAR
```
```env
✅ Correct
FOO=BAR
```
### Extra Blank Line
Detects if a file contains more than one blank line in a row:
```env
❌ Wrong
A=B
FOO=BAR
```
```env
❌ Wrong
A=B
FOO=BAR
```
```env
✅ Correct
A=B
FOO=BAR
```
```env
✅ Correct
A=B
FOO=BAR
```
### Incorrect delimiter
Detects if a key does not use an underscore to separate words:
```env
❌ Wrong
FOO-BAR=FOOBAR
✅ Correct
FOO_BAR=FOOBAR
```
### Key without value
Detects if a line has a key without a value:
```env
❌ Wrong
FOO
✅ Correct
FOO=
✅ Correct
FOO=BAR
```
### Leading character
Detects if a line starts with an unallowed character (characters from `A` to `Z` and `_` (underscore) are allowed):
```env
❌ Wrong
FOO=BAR
❌ Wrong
.FOO=BAR
❌ Wrong
*FOO=BAR
❌ Wrong
1FOO=BAR
✅ Correct
FOO=BAR
✅ Correct
_FOO=BAR
```
### Lowercase key
Detects if a key has lowercase characters:
```env
❌ Wrong
FOo_BAR=FOOBAR
❌ Wrong
foo_bar=FOOBAR
✅ Correct
FOO_BAR=FOOBAR
```
### Quote character
Detects if a value is wrapped in quotes:
```env
❌ Wrong
FOO="BAR"
❌ Wrong
FOO='BAR'
✅ Correct
FOO=BAR
```
### Space character
Detects lines with a whitespace around equal sign character `=`:
```env
❌ Wrong
FOO =BAR
❌ Wrong
FOO= BAR
❌ Wrong
FOO = BAR
✅ Correct
FOO=BAR
```
### Trailing whitespace
Detects if a line has a trailing whitespace.
### Unordered Key
Detects if a key is not alphabetically ordered:
```env
❌ Wrong
FOO=BAR
BAR=FOO
✅ Correct
BAR=FOO
FOO=BAR
```
## 🤝 Contributing
If you've ever wanted to contribute to open source, now you have a great opportunity:
* [How to set up the project](/CONTRIBUTING.md#how-to-set-up-the-project)
* [How to add a new check](/CONTRIBUTING.md#how-to-add-a-new-check)
## 👍 Similar projects
* [wemake-services/dotenv-linter](https://github.com/wemake-services/dotenv-linter) (Python)
## ✨ Contributors
This project exists thanks to all the people who contribute. [[Contribute](CONTRIBUTING.md)].
<a href="https://github.com/dotenv-linter/dotenv-linter/graphs/contributors"><img src="https://opencollective.com/dotenv-linter/contributors.svg?width=890&button=false" /></a>
## ♥️ Sponsors
<p>
<a href="https://evrone.com/?utm_source=github&utm_campaign=dotenv-linter">
<img src="https://www.mgrachev.com/assets/static/evrone-sponsored-300.png"
alt="Sponsored by Evrone" width="210">
</a>
</p>
Become a financial contributor and help us sustain our community.
<a href="https://opencollective.com/dotenv-linter"><img src="https://opencollective.com/dotenv-linter/individuals.svg?width=890"></a>
## 📃 License
[MIT](https://choosealicense.com/licenses/mit)
