Well, not exactly magic. According to Clarke's Law, any sufficiently advanced technology is indistimguishable from magic, so that is what we are dealing with here. I was struggling to come up with a more advanced example for tonight, but seripendipity came to my aid. Last month, I think I mentioned that Rancher Labs was hosting a Rancher Rodeo in Ottawa and that happened yesterday. While going through the introductory scenario for Kubernetes under Rancher, we used a service I think I have heard of in the past, but never really utilized - xip.io.
As a result, I solved the problem that was holding me back from a number of potential talks and we can all take advantage of it. More about that later.
With a little work, you will be able to duplicate the environment we are using to display the information for tonight.
We are all going to have a self-hosted git server with most of the features of Github or Gitlab, running in a Docker instance on our laptops, and the ability to reach anybody's server by DNS name from the local network. It should be fun and somewhat entertaining.
"How can that work?" you all ask sceptically.
"Well, that is why you are all here tonight. To learn a few new things." I reply with a maniacal laugh! [cue maniaical laugh]
Seriously though, the objective is to create a Docker Compose file that will assemble all of the requirements for such a service, set up the appriopriate services, expose them through the host computer and get you started on a simple web capable git service. This will be suitable for use on a Synology and other environments, so it does have practical applications.
Of course, this does require the environment from last month to still be on your systems. We will be building on the base system from last month and creating a new environment.
What will we be using for all of this?
- Docker
- Docker Compose
- Gitea
- PostgreSQL
- Traefik Reverse Proxy (we could also use nginx)
- Ubuntu
- Xip.io service
This is a modified version of the HOWTO Forge article: Install Gitea using Docker on Ububtu. It had most of what I wanted to describe and all it needed were a few tweaks to make if work for our talk. I doubt I changed much from the actual article.
Gitea is a fork of Gogs, the easy to use self-hosted Git service. It is similar to GitHub, Bitbucket, and Gitlab.
Gitea is:
- A lightweight code hosting solution written in Go.
- Can run on minimal hardware requirements.
- It is cross-platform, so it can run anywhere Go can be compiled such as Windows, Linux, MacOS, ARM etc.
You will:
- Create the basic infrastructure for your new container
- Author a suitable Docker Compose file (kind of an advanced Dockerfile)
- Install and configure the lightweight Git service Gitea.
- Deploy the Gitea server using Docker be using the PostgreSQL database and Traefik Reverse proxy.
- Full Docker install
- A working system based on last month's talk
- A little free space for the new container
- Your IP address that you are using tonight.
Verify you still have a Docker command line working: docker version
➜ ~ docker version
Client: Docker Engine - Community
Version: 19.03.1
API version: 1.40
Go version: go1.12.5
Git commit: 74b1e89
Built: Thu Jul 25 21:18:17 2019
OS/Arch: darwin/amd64
Experimental: false
Server: Docker Engine - Community
Engine:
Version: 19.03.1
API version: 1.40 (minimum version 1.12)
Go version: go1.12.5
Git commit: 74b1e89
Built: Thu Jul 25 21:17:52 2019
OS/Arch: linux/amd64
Experimental: true
containerd:
Version: v1.2.6
GitCommit: 894b81a4b802e4eb2a91d1ce216b8817763c29fb
runc:
Version: 1.0.0-rc8
GitCommit: 425e105d5a03fabd737a126ad93d62a9eeede87f
docker-init:
Version: 0.18.0
GitCommit: fec3683
If that doesn't work, make sure the docker service is running. That will depend on your laptop. On the Mac, there will be a docker whale in the top status bar.
Verify that is works with the hello-world container
➜ ~ docker run hello-world
Unable to find image 'hello-world:latest' locally
latest: Pulling from library/hello-world
1b930d010525: Pull complete
Digest: sha256:6540fc08ee6e6b7b63468dc3317e3303aae178cb8a45ed3123180328bcc1d20f
Status: Downloaded newer image for hello-world:latest
Hello from Docker!
This message shows that your installation appears to be working correctly.
To generate this message, Docker took the following steps:
1. The Docker client contacted the Docker daemon.
2. The Docker daemon pulled the "hello-world" image from the Docker Hub.
(amd64)
3. The Docker daemon created a new container from that image which runs the
executable that produces the output you are currently reading.
4. The Docker daemon streamed that output to the Docker client, which sent it
to your terminal.
To try something more ambitious, you can run an Ubuntu container with:
$ docker run -it ubuntu bash
Share images, automate workflows, and more with a free Docker ID:
https://hub.docker.com/
For more examples and ideas, visit:
https://docs.docker.com/get-started/
Verify that Docker Compose is available: docker-compose version
➜ ~ docker-compose version
docker-compose version 1.24.1, build 4667896b
docker-py version: 3.7.3
CPython version: 3.6.8
OpenSSL version: OpenSSL 1.1.0j 20 Nov 2018
We are going to create and deploy a Gitea container. First we will create the necessary environment for all of our requirements.
Create a new Docker network for the traefik
docker network ls
docker network create ovsagenet
docker network ls
You should now notice a new bridge network called ovsagenet.
Now create a directory called deployment
mkdir deployment
cd deployment
Create directories for Gitea and PostgreSQL
mkdir gitea postgres
Create an empty Docker Compose file
touch docker-compose.yml
Create a configuration file for the traefik reverse proxy
touch traefik.toml
Things should look like this:
➜ docker-gitea tree
.
├── deployment
│ ├── docker-compose.yml
│ ├── gitea
│ ├── postgres
│ └── traefik.toml
└── readme.md
The database service PostgreSQL is the first service that we want to configure. The database service will run only on the internal docker network.
And we will be using the Postgres 9.6 image, using 'gitea' as database name, user, and password, and set up the postgres data volume.
Edit the docker-compose.yml file and put the following in it:
version: "3"
networks:
ovsagenet:
external: true
internal:
external: false
services:
db:
image: postgres:9.6
restart: always
environment:
- POSTGRES_USER=gitea
- POSTGRES_PASSWORD=gitea
- POSTGRES_DB=gitea
labels:
- "traefik.enable=false"
networks:
- internal
volumes:
- ./postgres:/var/lib/postgresql/data
Save and continue editing. We will add the trafik configuration at the bottom next:
Where you see IPADDR, use the ip address you gathered earlier. If we were going to utilize HTTPS, we would also add port 443 below 80.
traefik:
image: traefik:latest
command: --docker
ports:
- 80:80
labels:
- "traefik.enable=true"
- "traefik.backend=dashboard"
- "traefik.frontend.rule=Host:traefik.IPADDR.xip.io"
- "traefik.port=8080"
networks:
- ovsagenet
volumes:
- /var/run/docker.sock:/var/run/docker.sock
- ./traefik.toml:/traefik.toml
container_name: traefik
restart: always
Save and continue editing.
Add the gitea portion below the trafik section:
server:
image: gitea/gitea:latest
environment:
- USER_UID=1000
- USER_GID=1000
restart: always
networks:
- internal
volumes:
- ./gitea:/data
ports:
- "3000"
- "22"
labels:
- "traefik.enabled=true"
- "traefik.backend=gitea"
- "traefik.frontend.rule=Host:git.IPADDR.xip.io"
- "traefik.docker.network=ovsagenet"
- "traefik.port=3000"
networks:
- internal
- ovsagenet
depends_on:
- db
- traefik
Now we configure the traefik.toml file
Edit traefik.toml and add the following:
Note the comments where we are disbaling things, If we wanted to utilize SSL/TLS, we would enable all of this and use LetsEncrypt to provide certificates.
#Traefik Global Configuration
debug = false
checkNewVersion = true
logLevel = "ERROR"
#Define the EntryPoint for HTTP and HTTPS
#defaultEntryPoints = ["https","http"]
defaultEntryPoints = ["http"]
#Define the HTTP port 80 and
#HTTPS port 443 EntryPoint
#Enable automatically redirect HTTP to HTTPS (which we will not do tonight)
[entryPoints]
[entryPoints.http]
address = ":80"
#[entryPoints.http.redirect]
#entryPoint = "https"
#[entryPoints.https]
#address = ":443"
#[entryPoints.https.tls]
#Enable Traefik Dashboard on port 8080
#with basic authentication method
#ovsage and password
[entryPoints.dash]
address=":8080"
[entryPoints.dash.auth]
[entryPoints.dash.auth.basic]
users = [
"ovsage:$apr1$hEgpZUN2$OYG3KwpzI3T1FqIg9LIbi.",
]
[api]
entrypoint="dash"
dashboard = true
#Enable retry sending a request if the network error
[retry]
#Define Docker Backend Configuration
[docker]
endpoint = "unix:///var/run/docker.sock"
domain = "xip.io"
watch = true
exposedbydefault = false
#Letsencrypt Registration
#Define the Letsencrypt ACME HTTP challenge (we are skipping this as well)
#[acme]
#email = "ovsage@gmail.com"
#storage = "acme.json"
#entryPoint = "https"
#OnHostRule = true
# [acme.httpChallenge]
# entryPoint = "http"
Save and exit.
If you made it to here, then when we build this container and run it, the Gitea service will be running on the TCP port '3000', using those two docker networks 'internal' and 'ovsagenet', and will run under the traefik reverse proxy on domain 'git.IPADDR.xip.io'.
Your Docker Compose configuration for Gitea deployment has been completed.
Also known as hurry up and wait.
Issue the command `docker-compose up -d' and wait a bit.
When it is finished, you will be able to run the command docker-compose ps and see interesting things.
➜ deployment docker-compose ps
Name Command State Ports
------------------------------------------------------------------------------------------------------------
deployment_db_1 docker-entrypoint.sh postgres Up 5432/tcp
deployment_server_1 /usr/bin/entrypoint /bin/s ... Up 0.0.0.0:32783->22/tcp,
0.0.0.0:32782->3000/tcp
traefik /traefik --docker Up 0.0.0.0:80->80/tcp
You can see that your services are up and running.
If you browse to http://git.IPADDR.xip.io, you will see the gitea splash page. Now you can start configuring. Go to http://git.IPADDR.xip.io/install to perform your initial configuration.
Select PostgreSQL, db as the host and gitea for the next three items. Leave
SSL disabled. Why gitea? Look at the docker-compose file for the configuration
you gave it.
Change the Site Title to your name. Makes it easy to see which git server we are connecting to.
Make sure that Server domain is set to git.IPADDR.xip.io
Make sure the Gitea Base URL is set to http://git.IPADDR.xip.io
Set the admin username, password and an email address.
Click the INSTALL button.
You should now be redirected to your repository dashboard.
- Docker upgrade. My version of Docker flagged an update when I loaded it while preparing for this. You can safely ignore it for now. You may want to update it on a higher speed network later.
- Read up on Gitea. It is an elegant solution for much of the things you would want a git ecosystem for.
- Look at docker-compose and what it actually does - management of your containers. Kubernetes is the "on steroids" version of this.