phpdotenv

PHP dotenv ========== Loads environment variables from `.env` to `$_ENV` and `$_SERVER` automagically, and optionally to `getenv()`.

## Why .env? **You should never store sensitive credentials in your code**. Storing [configuration in the environment](https://www.12factor.net/config) is one of the tenets of a [twelve-factor app](https://www.12factor.net/). Anything that is likely to change between deployment environments – such as database credentials or credentials for 3rd party services – should be extracted from the code into environment variables. Basically, a `.env` file is an easy way to load custom configuration variables that your application needs without having to modify .htaccess files or Apache/nginx virtual hosts. This means you won't have to edit any files outside the project, and all the environment variables are always set no matter how you run your project - Apache, Nginx, CLI, and even PHP's built-in webserver. It's WAY easier than all the other ways you know of to set environment variables, and you're going to love it! * NO editing virtual hosts in Apache or Nginx * NO adding `php_value` flags to .htaccess files * EASY portability and sharing of required ENV values * COMPATIBLE with PHP's built-in web server and CLI runner PHP dotenv is a PHP version of the original [Ruby dotenv](https://github.com/bkeepers/dotenv). ## Installation Installation is super-easy via [Composer](https://getcomposer.org/): ```bash composer require vlucas/phpdotenv ``` or add it by hand to your `composer.json` file. ## Upgrading We follow [semantic versioning](https://semver.org/), which means breaking changes may occur between major releases. We have upgrading guides for V2 to V3, V3 to V4 and V4 to V5 available [here](UPGRADING.md). ## Usage The `.env` file is generally kept out of version control since it can contain sensitive API keys and passwords. A separate `.env.example` file is created with all the required environment variables defined except for the sensitive ones, which are either user-supplied for their own development environments or are communicated elsewhere to project collaborators. The project collaborators then independently copy the `.env.example` file to a local `.env` and ensure all the settings are correct for their local environment, filling in the secret keys or providing their own values when necessary. In this usage, the `.env` file should be added to the project's `.gitignore` file so that it will never be committed by collaborators. This usage ensures that no sensitive passwords or API keys will ever be in the version control history so there is less risk of a security breach, and production values will never have to be shared with all project collaborators. Add your application configuration to a `.env` file in the root of your project. **Make sure the `.env` file is added to your `.gitignore` so it is not checked-in the code** ```shell S3_BUCKET="dotenv" SECRET_KEY="souper_seekret_key" ``` Now create a file named `.env.example` and check this into the project. This should have the ENV variables you need to have set, but the values should either be blank or filled with dummy data. The idea is to let people know what variables are required, but not give them the sensitive production values. ```shell S3_BUCKET="devbucket" SECRET_KEY="abc123" ``` You can then load `.env` in your application with: ```php $dotenv = Dotenv\Dotenv::createImmutable(__DIR__); $dotenv->load(); ``` To suppress the exception that is thrown when there is no `.env` file, you can: ```php $dotenv = Dotenv\Dotenv::createImmutable(__DIR__); $dotenv->safeLoad(); ``` Optionally you can pass in a filename as the second parameter, if you would like to use something other than `.env`: ```php $dotenv = Dotenv\Dotenv::createImmutable(__DIR__, 'myconfig'); $dotenv->load(); ``` Both the directory and the file name may also be given as arrays, in which case only the first readable file found is loaded. To merge every readable file instead, with later files overriding earlier ones, pass `false` as the third parameter. The file encoding may be specified using the fourth parameter: ```php $dotenv = Dotenv\Dotenv::createImmutable(__DIR__, ['.env', '.env.local'], false, 'UTF-8'); $dotenv->load(); ``` All of the defined variables are now available in the `$_ENV` and `$_SERVER` super-globals. ```php $s3_bucket = $_ENV['S3_BUCKET']; $s3_bucket = $_SERVER['S3_BUCKET']; ``` ### Putenv and Getenv Using `getenv()` and `putenv()` is strongly discouraged due to the fact that these functions are not thread safe, however it is still possible to instruct PHP dotenv to use these functions. Instead of calling `Dotenv::createImmutable`, one can call `Dotenv::createUnsafeImmutable` (or `Dotenv::createUnsafeMutable` instead of `Dotenv::createMutable`), which will add the `PutenvAdapter` behind the scenes. Your environment variables will now be available using the `getenv` method, as well as the super-globals: ```php $s3_bucket = getenv('S3_BUCKET'); $s3_bucket = $_ENV['S3_BUCKET']; $s3_bucket = $_SERVER['S3_BUCKET']; ``` ### Nesting Variables It's possible to nest an environment variable within another, useful to cut down on repetition. This is done by wrapping an existing environment variable in `${…}` e.g. ```shell BASE_DIR="/var/webroot/project-root" CACHE_DIR="${BASE_DIR}/cache" TMP_DIR="${BASE_DIR}/tmp" ``` Nested references must use the `${…}` syntax: a bare `$BASE_DIR` is never interpolated. Interpolation happens in unquoted and double-quoted values, but never inside single-quoted ones, and inside double quotes a reference can be escaped by writing `\${BASE_DIR}`. If a referenced variable is not defined, the reference is left in place verbatim rather than being replaced by an empty string. References are resolved from right to left, so a resolved inner reference can itself form part of an outer one. Resolution reads from the repository being loaded into, so when using `createImmutable`, a variable already present in `$_SERVER` or `$_ENV` takes precedence over the value defined in your file, and when using `createUnsafeImmutable`, values visible through `getenv()` and `putenv()` are read and protected as well. ### Quoting and Escaping Values may be unquoted, single-quoted or double-quoted. Single-quoted values are treated completely literally: no escape sequences are recognised, and no variables are interpolated. Backslashes in unquoted values are also treated literally. Inside double quotes, exactly the escape sequences `\"`, `\\`, `\$`, `\f`, `\n`, `\r`, `\t` and `\v` are recognised, with the character escapes producing their real control characters, and any other backslash sequence is a parse error, so a double-quoted Windows path must use doubled backslashes (or be single-quoted instead): ```shell WIN1='C:\Users\vlucas' WIN2="C:\\Users\\vlucas" ``` Only double-quoted values may span multiple lines: ```shell MESSAGE="Hello World" ``` A double-quoted value left unterminated at the end of the file is currently discarded silently, along with any lines that follow it. A line consisting of just a variable name with no equals sign will clear that variable from the environment when loading in mutable mode. ### Immutability and Repository Customization Immutability refers to if Dotenv is allowed to overwrite existing environment variables. If you want Dotenv to overwrite existing environment variables, use `createMutable` instead of `createImmutable`: ```php $dotenv = Dotenv\Dotenv::createMutable(__DIR__); $dotenv->load(); ``` A variable counts as existing if it is set in any of the repository's adapters, including values only present in `$_SERVER`, and once one immutable instance has loaded a variable, a second instance will treat it as existing too. Within a single load, however, an instance may overwrite a variable it wrote itself, which is how later files in a merge override earlier ones. The array returned by `load()` contains only the variables that were actually written, so variables skipped due to immutability are omitted. For validation or testing without touching the real environment, use `createArrayBacked`. Behind the scenes, this is instructing the "repository" to allow immutability or not. By default, the repository is configured to allow overwriting existing values by default, which is relevant if one is calling the "create" method using the `RepositoryBuilder` to construct a more custom repository: ```php $repository = Dotenv\Repository\RepositoryBuilder::createWithNoAdapters() ->addAdapter(Dotenv\Repository\Adapter\EnvConstAdapter::class) ->addWriter(Dotenv\Repository\Adapter\PutenvAdapter::class) ->immutable() ->make(); $dotenv = Dotenv\Dotenv::create($repository, __DIR__); $dotenv->load(); ``` The above example will write loaded values to `$_ENV` and `putenv`, but when interpolating environment variables, we'll only read from `$_ENV`. Moreover, it will never replace any variables already set before loading the file. By means of another example, one can also specify a set of variables to be allow listed. That is, only the variables in the allow list will be loaded: ```php $repository = Dotenv\Repository\RepositoryBuilder::createWithDefaultAdapters() ->allowList(['FOO', 'BAR']) ->make(); $dotenv = Dotenv\Dotenv::create($repository, __DIR__); $dotenv->load(); ``` ### Requiring Variables to be Set PHP dotenv has built in validation functionality, including for enforcing the presence of an environment variable. This is particularly useful to let people know any explicit required variables that your app will not work without. You can use a single string: ```php $dotenv->required('DATABASE_DSN'); ``` Or an array of strings: ```php $dotenv->required(['DB_HOST', 'DB_NAME', 'DB_USER', 'DB_PASS']); ``` If any ENV vars are missing, Dotenv will throw a `Dotenv\Exception\ValidationException` like this: ``` One or more environment variables failed assertions: DATABASE_DSN is missing. ``` ### Empty Variables Beyond simply requiring a variable to be set, you might also need to ensure the variable is not empty: ```php $dotenv->required('DATABASE_DSN')->notEmpty(); ``` If the environment variable is empty, you'd get an Exception: ``` One or more environment variables failed assertions: DATABASE_DSN is empty. ``` ### Integer Variables You might also need to ensure that the variable is of an integer value. You may do the following: ```php $dotenv->required('FOO')->isInteger(); ``` Note that only unsigned digit strings pass this check: signed values such as `-5` or `+5` are rejected. If the environment variable is not an integer, you'd get an Exception: ``` One or more environment variables failed assertions: FOO is not an integer. ``` One may only want to enforce validation rules when a variable is set. We support this too: ```php $dotenv->ifPresent('FOO')->isInteger(); ``` ### Boolean Variables You may need to ensure a variable is in the form of a boolean, accepting "true", "false", "On", "1", "Yes", "Off", "0" and "No", case-insensitively and ignoring surrounding whitespace. This check requires the `filter` extension. You may do the following: ```php $dotenv->required('FOO')->isBoolean(); ``` If the environment variable is not a boolean, you'd get an Exception: ``` One or more environment variables failed assertions: FOO is not a boolean. ``` Similarly, one may write: ```php $dotenv->ifPresent('FOO')->isBoolean(); ``` ### Allowed Values It is also possible to define a set of values that your environment variable should be. This is especially useful in situations where only a handful of options or drivers are actually supported by your code: ```php $dotenv->required('SESSION_STORE')->allowedValues(['Filesystem', 'Memcach