APIcast on Docker
You will need to configure APIcast in your 3scale Admin Portal as per the APIcast Overview, if you haven't done so already.
Step 1: Install Docker
This guide covers the steps to set up Docker on Red Hat Enterprise Linux (RHEL) 7.
Docker packages provided by Red Hat are released as part of the Extras channel in RHEL. To enable additional repositories, you can use either the Subscription Manager, or Yum config manager, see the RHEL product documentation for details.
For a RHEL 7 deployed on a AWS EC2 instance we'll use the following the instructions:
- List all repositories:
sudo yum repolist all
- Enable extras repository:
sudo yum-config-manager --enable rhui-REGION-rhel-server-extras
- Install Docker package:
sudo yum install docker
For other operating systems please refer to the Docker documentation on:
Step 2: Run the Docker Gateway
Start the Docker daemon:
sudo systemctl start docker.service
To check if the Docker daemon is running use the following command:
sudo systemctl status docker.service
You can download a ready to use Docker image from the Red Hat registry:
sudo docker pull registry.access.redhat.com/3scale-amp20/apicast-gateway:1.0
Run APIcast in a Docker container with the command:
sudo docker run --name apicast --rm -p 8080:8080 -e THREESCALE_PORTAL_ENDPOINT=https://<ACCESS_TOKEN>@<DOMAIN>-admin.3scale.net registry.access.redhat.com/3scale-amp20/apicast-gateway:1.0
<ACCESS_TOKEN> is an Access Token for the 3scale Account Management API, the Provider Key can also be used instead of the access token, and
<DOMAIN>-admin.3scale.net is the URL of your 3scale admin portal.
This command runs a Docker container called "apicast" on port
8080 and grabs the JSON configuration file from your 3scale portal. For other configuration options check out the APIcast Overview guide.
Here are some useful options that can be used with
docker run command:
--rmAutomatically remove the container when it exits
--detachRun container in background and print container ID. When it is not specified, the container runs in foreground mode, and you can stop it by
CTRL + c. When started in detached mode, you can reattach to the container with the docker attach command, for example,
docker attach apicast.
--publishPublish a container's port to the host. The value should have the format
<host port>:<container port>, so
-p 80:8080will bind port
8080of the container to port
80of the host machine.
For example, the Management API uses port
8090, so you may want to publish this port by adding
-p 8090:8090 to the
docker run command.
--envSet environment variables
--volumeMount a volume. The value is typically represented as
<host path>:<container path>[:<options>].
<options>is an optional attribute, it can be set to
:roto specify that the volume will be read only (it is mounted in read-write mode by default). Example:
See the Docker run reference for more information on available options.
Step 3: Testing APIcast
So now your Docker container is running with your own configuration file and the Docker image from the 3scale registry. You will want to test calls through APIcast on port
8080 and provide the correct authentication credentials which you can get from your 3scale account.
Test calls will not only verify that APIcast is running correctly but also that authentication and reporting is being handled successfully.
Step 4: Troubleshooting APIcast on Docker
Cannot connect to the Docker daemon error
If you see the error message:
docker: Cannot connect to the Docker daemon. Is the docker daemon running on this host?.
then it may be that the Docker service hasn't started. You can check the status of the Docker daemon by running
sudo systemctl status docker.service.
Make sure you are running as root user, as Docker requires root permissions in RHEL by default (see more information here).
Basic Docker commands
If you started the container in detached mode (
-d option) and want to check the logs for the running APIcast instance, you can use the
sudo docker logs <CONTAINER>
<CONTAINER> is the container name ("apicast" in the example above) or the container ID. You can get the list of the running containers and ther IDs and names with the command
sudo docker ps.
To stop the container, run
sudo docker stop <CONTAINER>. You can also remove the container by running
sudo docker rm <CONTAINER>.
Please refer to Docker commands reference for more information on available commands.
Step 5: Customising the Gateway
There are some customizations that cannot be managed through the admin portal and require writing custom logic to APIcast itself.
Custom Lua logic
The easiest way to customise APIcast logic is to rewrite the existing file with your own and attach it as a volume.
-v flag attaches the local file to the stated path in the Docker container.
Customising the configuration files
The same steps apply to custom configuration files as the Lua scripting. If you just want to add to the existing conf files rather than overwrite then ensure the name of your new file does not clash with pre-existing ones. This will automatically be included in the main nginx.conf.
To make edits to the config.json you can grab this file from your admin portal with the following URL:
https://<account>-admin.3scale.net/admin/api/nginx/spec.json and copy & paste the contents locally. You can pass this local JSON file with the following command to start APIcast:
docker run --name apicast --rm -p 8080:8080 -v $(pwd)/path_to/config.json:/opt/app/config.json:ro -e THREESCALE_CONFIG_FILE=/opt/app/config.json
You should now be able to run APIcast on Docker. For other deployment options, check out the related articles.