This file contains notes and code examples for using Docker.
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## UBUNTU INSTALLATION
@ -49,7 +53,7 @@ You can reboot to make it take effect or...
`su - ${USER}`
## IMAGES AND CONTAINERS
## CONCEPTS
### Images
@ -61,32 +65,47 @@ Containers are packages that contain the application and the environment in whic
## IMAGES
Two ways to get images
### Define your own image using a Dockerfile
1. Get a premade image from a place like DockerHub.
2. Create your own image using a Dockerfile
Create a Dockerfile in the project directory. This file is a set of instructions for building a container.
### Run a container from a DockerHub image
```
# the baseImage is either a name from DockerHub or is the
# name of an Image on your system
FROM node
`docker run node`
# tell Docker where to run commands from
WORKDIR /app
This command will create and run a container instance from the image. In this example it is using the office nodejs image to create a running instance in a container. Note: this command as it is doesn't do much.
# tell Docker which files go into the image
# COPY localFolder imageFolder
COPY . /app
`docker run -it node`
# do some node stuff
RUN npm install
Adding the -it flag creates an interactive terminal instance where you can interact with the instance of node.
# show the port to the world outside of Docker so that the
# web pages are visible
EXPOSE 80
# these commands are executed when a container is instanced
CMD ["node", "server.js"]
```
### Basic build command
### Build an image from the Dockerfile.
Using this command results in a random Image ID that you use to run a container. This is not the way.
`docker build .`
### Assign a Name:Tag to the build
### Assign a Name:Tag to the image
Assign a name and tag to the image because you are a responsible dev.
`docker build -t name:tag .`
## MANAGING IMAGES
### List out the images installed on this server
@ -98,6 +117,26 @@ Assign a name and tag to the image because you are a responsible dev.
### Remove all dangling (untagged) images
`docker image prune`
## CONTAINERS
### Run a container from a DockerHub image
`docker run node`
This command will create and run a container instance from the image. In this example it is using the office nodejs image to create a running instance in a container. Note: this command as it is doesn't do much.
`docker run -it node`
Adding the -it flag creates an interactive terminal instance where you can interact with the instance of node.
### Running a container from your own image
After the image is built you will get an ID for the image. Use the ID to start the container. If you are a good dev, then you assigned a name:tag and you use that instead.
