feat: very basic context management

Taken from this gist by github.com/agbaraka

https://gist.github.com/agbaraka/654a218f8ea13b3da8a47d47595f5d05

There is no in-built way of dealing with contexts using the golang sdk.

This means we have to make our own Dial helper borrowing from Docker CLI

This means all Docker API calls are made within the ssh connection

This uses `docker system dial-stdio`

client/client.go

@@ -0,0 +1,45 @@
+package client
+
+import (
+	"fmt"
+	"net/http"
+	"os"
+
+	"github.com/docker/docker/client"
+)
+
+func NewClientWithContext(contextURL string) *client.Client {
+	helper := newConnectionHelper(contextURL)
+	httpClient := &http.Client{
+		// No tls
+		// No proxy
+		Transport: &http.Transport{
+			DialContext: helper.Dialer,
+		},
+	}
+
+	var clientOpts []client.Opt
+
+	clientOpts = append(clientOpts,
+		client.WithHTTPClient(httpClient),
+		client.WithHost(helper.Host),
+		client.WithDialContext(helper.Dialer),
+	)
+
+	// FIXME: Maybe don't have this variable here and load it beforehand
+	version := os.Getenv("DOCKER_API_VERSION")
+
+	if version != "" {
+		clientOpts = append(clientOpts, client.WithVersion(version))
+	} else {
+		clientOpts = append(clientOpts, client.WithAPIVersionNegotiation())
+	}
+
+	cl, err := client.NewClientWithOpts(clientOpts...)
+
+	if err != nil {
+		fmt.Println("Unable to create docker client")
+		panic(err)
+	}
+	return cl
+}

client/connection.go

@@ -0,0 +1,12 @@
+package client
+
+import "github.com/docker/cli/cli/connhelper"
+
+func newConnectionHelper(daemonURL string) *connhelper.ConnectionHelper {
+	helper, err := connhelper.GetConnectionHelper(daemonURL)
+
+	if err != nil {
+		panic(err)
+	}
+	return helper
+}