feat(worker): Implemented docker executor, close #55

if docker is enabled in configure file and `docker_image` is set on mirror config, the command would

be executed via `docker run ...`

worker/docker_test.go

@@ -0,0 +1,97 @@
+package worker
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"testing"
+	"time"
+
+	"github.com/codeskyblue/go-sh"
+	. "github.com/smartystreets/goconvey/convey"
+)
+
+func getDockerByName(name string) (string, error) {
+	// docker ps -f 'name=$name' --format '{{.Names}}'
+	out, err := sh.Command(
+		"docker", "ps",
+		"--filter", "name="+name,
+		"--format", "{{.Names}}",
+	).Output()
+	return string(out), err
+}
+
+func TestDocker(t *testing.T) {
+	Convey("Docker Should Work", t, func(ctx C) {
+		tmpDir, err := ioutil.TempDir("", "tunasync")
+		defer os.RemoveAll(tmpDir)
+		So(err, ShouldBeNil)
+		cmdScript := filepath.Join(tmpDir, "cmd.sh")
+		tmpFile := filepath.Join(tmpDir, "log_file")
+		expectedOutput := "HELLO_WORLD"
+
+		c := cmdConfig{
+			name:        "tuna-docker",
+			upstreamURL: "http://mirrors.tuna.moe/",
+			command:     "/bin/cmd.sh",
+			workingDir:  tmpDir,
+			logDir:      tmpDir,
+			logFile:     tmpFile,
+			interval:    600 * time.Second,
+			env: map[string]string{
+				"TEST_CONTENT": expectedOutput,
+			},
+		}
+
+		cmdScriptContent := `#!/bin/sh
+echo ${TEST_CONTENT}
+sleep 10
+`
+		err = ioutil.WriteFile(cmdScript, []byte(cmdScriptContent), 0755)
+		So(err, ShouldBeNil)
+
+		provider, err := newCmdProvider(c)
+		So(err, ShouldBeNil)
+
+		d := &dockerHook{
+			provider: provider,
+			image:    "alpine",
+			volumes: []string{
+				fmt.Sprintf("%s:%s", cmdScript, "/bin/cmd.sh"),
+			},
+		}
+		provider.AddHook(d)
+		So(provider.Docker(), ShouldNotBeNil)
+
+		err = d.preExec()
+		So(err, ShouldBeNil)
+
+		go func() {
+			err = provider.Run()
+			ctx.So(err, ShouldNotBeNil)
+		}()
+
+		time.Sleep(1 * time.Second)
+
+		// assert container running
+		names, err := getDockerByName(d.Name())
+		So(err, ShouldBeNil)
+		So(names, ShouldEqual, d.Name()+"\n")
+
+		err = provider.Terminate()
+		So(err, ShouldBeNil)
+
+		// container should be terminated and removed
+		names, err = getDockerByName(d.Name())
+		So(err, ShouldBeNil)
+		So(names, ShouldEqual, "")
+
+		// check log content
+		loggedContent, err := ioutil.ReadFile(provider.LogFile())
+		So(err, ShouldBeNil)
+		So(string(loggedContent), ShouldEqual, expectedOutput+"\n")
+
+		d.postExec()
+	})
+}