<p>Here's a small sample program which shows how you can access the <a href="https://www.docker.com">Docker CLI</a> from within a Go program using the <a href="https://github.com/moby/moby/tree/master/client">Docker API</a>.</p>
<p>We'll start simple with showing how to list the running containers</p>
<p>We first start with creating an empty project:</p>
<pre><code>$ mkdir list-docker-containers
$ cd list-docker-containers
$ go mod init github.com/pieterclaerhout/go-example/go-list-docker-containers</code></pre>
<p>In there, we create a <code>main.go</code> file containing:</p>
<div class="highlight"><pre><span></span><span class="kn">package</span> <span class="nx">main</span>
<span class="kn">import</span> <span class="p">(</span>
<span class="s">"context"</span>
<span class="s">"github.com/docker/docker/api/types"</span>
<span class="s">"github.com/docker/docker/client"</span>
<span class="s">"github.com/pieterclaerhout/go-log"</span>
<span class="p">)</span>
<span class="kd">func</span> <span class="nx">main</span><span class="p">()</span> <span class="p">{</span>
<span class="nx">log</span><span class="p">.</span><span class="nx">PrintColors</span> <span class="p">=</span> <span class="kc">true</span>
<span class="nx">log</span><span class="p">.</span><span class="nx">PrintTimestamp</span> <span class="p">=</span> <span class="kc">false</span>
<span class="nx">cli</span><span class="p">,</span> <span class="nx">err</span> <span class="o">:=</span> <span class="nx">client</span><span class="p">.</span><span class="nx">NewEnvClient</span><span class="p">()</span>
<span class="nx">log</span><span class="p">.</span><span class="nx">CheckError</span><span class="p">(</span><span class="nx">err</span><span class="p">)</span>
<span class="nx">containers</span><span class="p">,</span> <span class="nx">err</span> <span class="o">:=</span> <span class="nx">cli</span><span class="p">.</span><span class="nx">ContainerList</span><span class="p">(</span><span class="nx">context</span><span class="p">.</span><span class="nx">Background</span><span class="p">(),</span> <span class="nx">types</span><span class="p">.</span><span class="nx">ContainerListOptions</span><span class="p">{</span>
<span class="nx">All</span><span class="p">:</span> <span class="kc">true</span><span class="p">,</span>
<span class="p">})</span>
<span class="nx">log</span><span class="p">.</span><span class="nx">CheckError</span><span class="p">(</span><span class="nx">err</span><span class="p">)</span>
<span class="k">for</span> <span class="nx">_</span><span class="p">,</span> <span class="nx">container</span> <span class="o">:=</span> <span class="k">range</span> <span class="nx">containers</span> <span class="p">{</span>
<span class="nx">log</span><span class="p">.</span><span class="nx">InfoDump</span><span class="p">(</span><span class="nx">container</span><span class="p">,</span> <span class="nx">container</span><span class="p">.</span><span class="nx">Image</span><span class="p">)</span>
<span class="p">}</span>
<span class="p">}</span>
</pre></div>
<p>The way it works is pretty simple. We first setup the logging (we are using <a href="https://github.com/pieterclaerhout/go-log">go-log</a> for this. We then create a client from the current environment (which should auto-detect your Docker installation). The, we can ask the API to use <code>ContainerList</code> to get the full list of running containers.</p>
<p>To test, make sure you have one or more Docker containers running. You can start one by running a <a href="http://redis.io">Redis server</a> for example:</p>
<pre><code>$ docker run redis:alpine</code></pre>
<p>Then run our program from within the project directory and you should get a list of the running containers with all their details:</p>
<pre><code>$ go run .
redis:alpine types.Container{
ID: "ef6a2229985cb6bd9ee1595c5b0c4e4a3e4d14282a863dd2f4d9a3d6c68f2b6a",
Names: []string{
"/brave_hoover",
},
Image: "redis:alpine",
ImageID: "sha256:c1949ec48c51d73e24be652eb3bcba0477121d7970f05abc234c2d5aef97d1a7",
Command: "docker-entrypoint.sh redis-server",
Created: 1610642670,
Ports: []types.Port{
types.Port{
IP: "",
PrivatePort: 6379,
PublicPort: 0,
Type: "tcp",
},
},
SizeRw: 0,
SizeRootFs: 0,
Labels: map[string]string{
},
State: "running",
Status: "Up 3 seconds",
HostConfig: struct { NetworkMode string "json:\",omitempty\"" }{
NetworkMode: "default",
},
NetworkSettings: &types.SummaryNetworkSettings{
Networks: map[string]*network.EndpointSettings{
"bridge": &network.EndpointSettings{
IPAMConfig: nil,
Links: nil,
Aliases: nil,
NetworkID: "77b41b91ce98cf3a2ac8c7d4ce0984bc125eb6f8e656afb500d49ea195a1493d",
EndpointID: "7c0cd8205d04df21d412b27e783422eb27bfa31ccf1b2bcf81e4252ce91f9600",
Gateway: "172.17.0.1",
IPAddress: "172.17.0.2",
IPPrefixLen: 16,
IPv6Gateway: "",
GlobalIPv6Address: "",
GlobalIPv6PrefixLen: 0,
MacAddress: "02:42:ac:11:00:02",
DriverOpts: map[string]string{
},
},
},
},
Mounts: []types.MountPoint{
types.MountPoint{
Type: "volume",
Name: "0e689f87f96d0f4b7e84bf6063f884a0ceb4f7b8977cf6422db0b662b109673b",
Source: "",
Destination: "/data",
Driver: "local",
Mode: "",
RW: true,
Propagation: "",
},
},
}</code></pre>
