# Docker Service

> wdio-docker-service is a 3rd party package, for more information please see [GitHub](https://github.com/stsvilik/wdio-docker-service) | [npm](https://www.npmjs.com/package/wdio-docker-service)

This service is intended for use with [WebdriverIO](http://webdriver.io/) and it helps run functional/integration tests against/using containerized applications. It uses popular [Docker](https://www.docker.com/) service (installed separately) to run containers.

## Why use it?[​](#why-use-it "Direct link to Why use it?")

Ideally your tests would run in some variety of CI/CD pipeline where often there are no "real" browsers and other resources your application depends on. With advent of Docker practically all necessary application dependencies can be containerized. With this service you may run your application container or a [docker-selenium](https://github.com/SeleniumHQ/docker-selenium) in your CI and in complete isolation (assuming CI can have Docker installed as a dependency). Same may apply to local development if your application needs to have a level of isolation from your main OS.

## How it works[​](#how-it-works "Direct link to How it works")

Service will run an existing docker image and once its ready, will initiate WebdriverIO tests that should run against your containerized application.

## Installation[​](#installation "Direct link to Installation")

Run:

```
npm install wdio-docker-service --save-dev
```

Instructions on how to install WebdriverIO can be found [here](https://webdriver.io/docs/gettingstarted).

## Configuration[​](#configuration "Direct link to Configuration")

By default, Google Chrome, Firefox and PhantomJS are available when installed on the host system. In order to use the service you need to add `docker` to your service array:

```
// wdio.conf.ts
export const config: WebdriverIO.Config = {
   // ...
   services: ['docker'],
   // ...
};
```

## Options[​](#options "Direct link to Options")

### dockerOptions[​](#dockeroptions "Direct link to dockerOptions")

Various options required to run docker container

Type: `Object`

Default: `{ options: { rm: true } }`

Example:

```
dockerOptions: {
    image: 'selenium/standalone-chrome',
    healthCheck: 'http://localhost:4444',
    options: {
        p: ['4444:4444'],
        shmSize: '2g'
    }
}
```

### dockerOptions.image[​](#dockeroptionsimage "Direct link to dockerOptions.image")

Docker container name tag. Could be local or from Docker HUB.

Type: `String`

Required: `true`

### dockerOptions.healthCheck[​](#dockeroptionshealthcheck "Direct link to dockerOptions.healthCheck")

Configuration which checks your containers' readiness before initiating tests. Normally this would be a localhost url. If healthCheck is not configured, Webdriver will start running tests immediately after Docker container starts, which maybe too early considering that it takes time for web service to start inside a Docker container.

Type: `String|Object`

Options for Object use:

* *url* - url to an app running inside your container
* *maxRetries* - number of retries until healthcheck fails. Default: 10
* *inspectInterval* - interval between each retry in ms. Default: 500
* *startDelay* - initial delay to begin healthcheck in ms. Default: 0

Example 1 (String): `healthCheck: 'http://localhost:4444'`

Example 2 (Object):

```
healthCheck: {
    url: 'http://localhost:4444',
    maxRetries: 3,
    inspectInterval: 1000,
    startDelay: 2000
}
```

### dockerOptions.options[​](#dockeroptionsoptions "Direct link to dockerOptions.options")

Map of options used by `docker run` command. For more details on `run` command click [here](https://docs.docker.com/edge/engine/reference/commandline/run/).

Any single-letter option will be converted to `-[option]` (i.e. `d: true` -> `-d`).

Any option of two-character or more will be converted to `--[option]` (i.e. `rm: true` -> `--rm`).

For options that may be used more than once (i.e. `-e`,`-add-host`, `--expose`, etc.), please use array notation (i.e. `e: ["NODE_ENV=development", "FOO=bar"]`).

Type: `Object`

Example:

```
options: {
    e: ['NODE_ENV=development', 'PROXY=http://myproxy:80']
    p: ['4444:4444', '5900:5900'],
    shmSize: '2g'
}
```

### dockerOptions.args[​](#dockeroptionsargs "Direct link to dockerOptions.args")

Any arguments you may want to pass into container. Corresponds to `[ARG...]` in Docker run CLI.

Type: `String`

### dockerOptions.command[​](#dockeroptionscommand "Direct link to dockerOptions.command")

Any command you may want to pass into container. Corresponds to `[COMMAND]` in Docker run CLI.

Type: `String`

### onDockerReady[​](#ondockerready "Direct link to onDockerReady")

A callback method which is called when Docker application is ready. Readiness is determined by ability to ping `healthCheck` url.

Type: `Function`

### dockerLogs[​](#dockerlogs "Direct link to dockerLogs")

Path to where logs from docker container should be stored

Type: `String`

## Testing Use Cases / Recipes[​](#testing-use-cases--recipes "Direct link to Testing Use Cases / Recipes")

Please visit our [Wiki](https://github.com/stsvilik/wdio-docker-service/wiki) for more details.