platformsh-config

Platform.sh Config Reader (Node.js)

This library provides a streamlined and easy to use way to interact the a Platform.sh environment. It offers utility methods to access routes and relationships more cleanly than reading the raw environment variables yourself.

This library requires Node.js 10 or later.

Install

npm install platformsh-config --save

Usage Example

Example:

const mysql = require('mysql2/promise');
const config = require("platformsh-config").config();

if (!config.isValidPlatform()) {
    process.exit('Not in a Platform.sh Environment.');
}

const credentials = config.credentials('database');

const connection = await mysql.createConnection({
    host: credentials.host,
    port: credentials.port,
    user: credentials.username,
    password: credentials.password,
    database: credentials.path,
});

// Do stuff with connection.

// Note the use of config.port.
app.listen(config.port, function() {
    console.log(`Listening on port ${config.port}`)
});

API Reference

Create a config object

const config = require("platformsh-config").config();

config is now a Config object that provides access to the Platform.sh environment.

The isValidPlatform() method returns true if the code is running in a context that has Platform.sh environment variables defined. If it returns false then most other functions will throw exceptions if used.

Inspect the environment

The following methods return true or false to help determine in what context the code is running:

config.inBuild();

config.inRuntime();

config.onEnterprise();

config.onProduction();

Read environment variables

The following magic properties return the corresponding environment variable value. See the Platform.sh documentation for a description of each.

The following are available both in Build and at Runtime:

config.applicationName;

config.appDir;

config.project;

config.treeId;

config.projectEntropy;

The following are available only if inRuntime() returned true:

config.branch;

config.documentRoot;

config.smtpHost;

config.environment;

config.socket;

config.port;

Reading service credentials

Platform.sh services are defined in a services.yaml file, and exposed to an application by listing a relationship to that service in the application's .platform.app.yaml file. User, password, host, etc. information is then exposed to the running application in the PLATFORM_RELATIONSHIPS environment variable, which is a base64-encoded JSON string. The following method allows easier access to credential information than decoding the environment variable yourself.

creds = config.credentials('database');

The return value of credentials() is a an object matching the relationship JSON object, which includes the appropriate user, password, host, database name, and other pertinent information. See the Service documentation for your service for the exact structure and meaning of each property. In most cases that information can be passed directly to whatever other client library is being used to connect to the service.

Formatting service credentials

In some cases the library being used to connect to a service wants its credentials formatted in a specific way; it could be a DSN string of some sort or it needs certain values concatenated to the database name, etc. For those cases you can use "Credential Formatters". A Credential Formatter is any function that takes a credentials object and returns any type, since the library may want different types.

Credential Formatters can be registered on the configuration object, and a few are included out of the box. That allows 3rd party libraries to ship their own formatters that can be easily integrated into the Config object to allow easier use.

function formatMyService(credentials) {
	return "some string based on credentials";
}

// Call this in setup.
config.registerFormatter("my_service", formatMyService);


// Then call this method to get the formatted version

formatted = config.FormattedCredentials("database", "my_service");

The first parameter is the name of a relationship defined in .platform.app.yaml. The second is a formatter that was previously registered with registerFormatter(). If either the service or formatter is missing an exception will be thrown. The type of formatted will depend on the formatter function and can be safely passed directly to the client library.

Two formatters are included out of the box:

• solr-node returns an object appropriate for the solr-node library. solr-node needs the collection name on its own while the relationship's path property by default is a full URL path. This formatter handles that conversion.
• mongodb returns a DSN to use with the mongodb client library's connect() method. Note that the credentials object is still needed to pass the database name (the path property) to the db() method.

Reading Platform.sh variables

Platform.sh allows you to define arbitrary variables that may be available at build time, runtime, or both. They are stored in the PLATFORM_VARIABLES environment variable, which is a base64-encoded JSON string.

The following two methods allow access to those values from your code without having to bother decoding the values yourself:

config.variables();

This method returns an associative array of all variables defined. Usually this method is not necessary and config.variable() is preferred.

config.variable("foo", "default");

This method looks for the "foo" variable. If found, it is returned. If not, the optional second parameter is returned as a default.

Reading Routes

Routes on Platform.sh define how a project will handle incoming requests; that primarily means what application container will serve the request, but it also includes cache configuration, TLS settings, etc. Routes may also have an optional ID, which is the preferred way to access them.

config.route("main");

The route() method takes a single string for the route ID ("main" in this case) and returns the corresponding route object. If the route is not found it will throw an exception.

To access all routes, or to search for a route that has no ID, the routes() method returns a list of all route objects keyed by their URL. That mirrors the structure of the PLATFORM_ROUTES environment variable.

If called in the build phase an exception is thrown.