Dockerode Utils
Set of useful functions for working with dockerode.
TOC
- [pullImageAsync](#pullimageasyncdockerode-imagename-onprogress) pull docker image and wait to finish download. You can track progress.- [execCommand](#execcommandcontainer-cmd) execute shell command inside a running container, returns output.- [waitForOutput](#waitforoutputcontainer-predicate-timeout--15000) wait for specific string to appear in running container's `stdout`.- [imageExists](#imageexistsdockerode-imagenames) check if image with imageName already exists.Installation
npm ```bash npm install dockerode-utils --save ``` yarn ```bash yarn add dockerode-utils ```API
pullImageAsync(dockerode, imageName, onProgress?)
```typescript
pullImageAsync(dockerode: Dockerode, imageName: string, onProgress?: (output: string) => void): void
```
Will pull docker image, you can wait for finish or track a progress. If you forget to specify
:tag, it'll download :latest
```javascript
/
Example how to pull alpine:latest image from dockerhub
/
import as Dockerode from 'dockerode';
import { pullImageAsync } from 'dockerode-utils';
const dockerode = new Dockerode();
await pullImageAsync(dockerode, 'alpine:latest');
```
execCommand(container, cmd)
```typescript
execCommand(container: Dockerode.Container, cmd: string): string
```
Execute shell command in container and returns output as string[].
```javascript
/
Print list of env from docker container
/
import as Dockerode from 'dockerode';
import { execCommand } from 'dockerode-utils';
// first, we need to create a container
const dockerode = new Dockerode();
const alpineContainer = await dockerode.run('alpine', , {}, null);
const envList = execCommand(alpineContainer, 'env');
console.log(envList);
// command with argument
const envList2 = execCommand(alpineContainer, 'env', '--help');
console.log(envList2);
```
waitForOutput(container, predicate, timeout = 15000)
```typescript
waitForOutput(container: Dockerode.Container, predicate: (output: string) => boolean, timeout: number = 15000)
```
Wait for specific output from container. Useful, when you're working
with container, in which is running daemon and you have to wait for specific output/line to appears in container.
```javascript
/
Example with waiting for specific output.
Here, we're waiting for 'InnoDB: 5.7.18 started' to appears in mysql container
only after that, we know that mysql container is fully initialized and we can
continue executing commands
/
import as Dockerode from 'dockerode';
import { waitForOutput } from 'dockerode-utils';
const dockerode = new Dockerode();
const mysqlContainer = await dockerode.run('mysql:5.7.18', , {}, null);
await waitForOutput(mysqlContainer, (line) => line === 'InnoDB: 5.7.18 started');
console.log('MySql db started');
```
imageExists(dockerode, ...imageNames)
```typescript
imageExists(dockerode: Dockerode, ...imageNames: string | string): boolean
```
Check if images with imageNames exist. You can check more than one image at once, like imageExists(dockerode, ['mongo', 'mysql']) or only one imageExists(dockerode, 'mongo'). In case, you won't define :tag it'll check if any image with imageName prefix exists.
