run snake-runner in docker

Taskfile.yml

@@ -11,14 +11,25 @@ vars:
 
 includes:
   go: tasks/go.yml
+  docker: tasks/docker.yml
 
 tasks:
   rr:
     cmds:
-      - task: reset
-      - task: build
+      - task: go:build
       - mkdir -p .runners/{{ .random_uuid }}
       - SNAKE_NAME={{ .random_uuid }}
         SNAKE_TOKEN_PATH=.runners/{{.random_uuid}}/token
         SNAKE_SSH_KEY_PATH=.runners/{{.random_uuid}}/id_rsa
-        ./snake-runner -c ./conf/snake.dev.conf
+        ./snake-runner -c ./conf/dev.conf
+  dock:
+    deps: [docker:alpine]
+    cmds:
+      - docker run -it
+          -e SNAKE_MASTER_ADDRESS=6.2.0.bitbucket:7990
+          -e SNAKE_DOCKER_NETWORK=bitbucket
+          -v /var/lib/snake-runner/secrets:{{.pwd}}/secrets
+          -v /var/run/docker.sock:/var/run/docker.sock
+          --rm
+          --network bitbucket
+          snake-runner

cmd/snake-runner/main.go

@@ -5,6 +5,7 @@ import (
 	"syscall"
 
 	"github.com/docopt/docopt-go"
+	"github.com/reconquest/karma-go"
 	"github.com/reconquest/pkg/log"
 	"github.com/reconquest/sign-go"
 )
@@ -42,6 +43,8 @@ func main() {
 		log.Fatal(err)
 	}
 
+	log.Infof(karma.Describe("version", version), "starting snake-runner")
+
 	config, err := LoadRunnerConfig(options.ConfigPathValue)
 	if err != nil {
 		log.Fatal(err)
@@ -55,6 +58,8 @@ func main() {
 		log.SetLevel(log.LevelTrace)
 	}
 
+	log.Infof(nil, "runner name: %s", config.Name)
+
 	runner := NewRunner(config)
 	runner.Start()
 

cmd/snake-runner/runner.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"net/http"
-	"os"
 	"strings"
 	"time"
 
@@ -21,27 +20,12 @@ type Runner struct {
 	client    *http.Client
 	config    *RunnerConfig
 	scheduler *Scheduler
-
-	name string
 }
 
 func NewRunner(config *RunnerConfig) *Runner {
-	name := config.Name
-	if name == "" {
-		hostname, err := os.Hostname()
-		if err != nil {
-			panic(err)
-		}
-
-		name = hostname
-	}
-
-	log.Infof(nil, "starting runner: %s", name)
-
 	return &Runner{
 		config: config,
 		client: http.DefaultClient,
-		name:   name,
 	}
 }
 
@@ -88,7 +72,7 @@ func (runner *Runner) request() *Request {
 		BaseURL(master+MasterPrefixAPI).
 		UserAgent("snake-runner/"+version).
 		// required by bitbucket itself
-		Header(NameHeader, runner.name).
+		Header(NameHeader, runner.config.Name).
 		Header(TokenHeader, runner.config.Token).
 		Header("X-Atlassian-Token", "no-check")
 }

cmd/snake-runner/runner_config.go

@@ -1,24 +1,29 @@
 package main
 
 import (
+	"fmt"
 	"io/ioutil"
 	"os"
-	"os/exec"
+	"path/filepath"
 	"runtime"
 	"strings"
 	"time"
 
 	"gopkg.in/yaml.v2"
 
 	"github.com/kovetskiy/ko"
-	"github.com/reconquest/executil-go"
 	"github.com/reconquest/karma-go"
 	"github.com/reconquest/pkg/log"
+	"github.com/reconquest/snake-runner/internal/sshkey"
+)
+
+const (
+	defaultBlockSize = 4096
 )
 
 type RunnerConfig struct {
-	ListenAddress string `yaml:"listen_address"  env:"SNAKE_LISTEN_ADDRESS" required:"true" default:":8585" `
-	MasterAddress string `yaml:"master_address" env:"SNAKE_MASTER_ADDRESS" required:"true"`
+	// it's actually required but it will be handled manually
+	MasterAddress string `yaml:"master_address" env:"SNAKE_MASTER_ADDRESS"`
 
 	Log struct {
 		Debug bool `yaml:"debug" env:"SNAKE_LOG_DEBUG"`
@@ -28,15 +33,17 @@ type RunnerConfig struct {
 	Name string `yaml:"name" env:"SNAKE_NAME"`
 
 	Token     string `yaml:"token" env:"SNAKE_TOKEN"`
-	TokenPath string `yaml:"token_path" env:"SNAKE_TOKEN_PATH" default:"/etc/snake-runner/token"`
+	TokenPath string `yaml:"token_path" env:"SNAKE_TOKEN_PATH" default:"/var/lib/snake-runner/secrets/token"`
 
 	HeartbeatInterval time.Duration `yaml:"heartbeat_interval" default:"30s"`
 	SchedulerInterval time.Duration `yaml:"scheduler_interval" default:"5s"`
 
-	Virtualization       string `yaml:"virtualization" default:"docker" required:"true"`
-	MaxParallelPipelines int64  `yaml:"max_parallel_pipelines" default:"0" required:"true"`
+	Virtualization       string `yaml:"virtualization" default:"docker" env:"SNAKE_VIRTUALIZATION" required:"true"`
+	MaxParallelPipelines int64  `yaml:"max_parallel_pipelines" env:"SNAKE_MAX_PARALLEL_PIPELINES" default:"0" required:"true"`
 
-	SSHKey string `yaml:"ssh_key" env:"SNAKE_SSH_KEY_PATH" default:"/etc/snake-runner/id_rsa" required:"true"`
+	SSHKey string `yaml:"ssh_key" env:"SNAKE_SSH_KEY_PATH" default:"/var/lib/snake-runner/secrets/id_rsa" required:"true"`
+
+	DockerNetwork string `yaml:"docker_network" env:"SNAKE_DOCKER_NETWORK"`
 }
 
 func LoadRunnerConfig(path string) (*RunnerConfig, error) {
@@ -48,6 +55,11 @@ func LoadRunnerConfig(path string) (*RunnerConfig, error) {
 		return nil, err
 	}
 
+	if config.MasterAddress == "" {
+		showMessageNoConfiguration()
+		os.Exit(1)
+	}
+
 	if config.TokenPath != "" && config.Token == "" {
 		tokenData, err := ioutil.ReadFile(config.TokenPath)
 		if err != nil && !os.IsNotExist(err) {
@@ -66,11 +78,23 @@ func LoadRunnerConfig(path string) (*RunnerConfig, error) {
 	}
 
 	if !isFileExists(config.SSHKey) && !isFileExists(config.SSHKey+".pub") {
-		log.Warningf(nil, "ssh key not found at %s, generating it", config.SSHKey)
-
-		_, _, err := executil.Run(
-			exec.Command("ssh-keygen", "-t", "rsa", "-C", "snake-runner", "-f", config.SSHKey),
+		log.Warningf(
+			nil,
+			"SSH key not found, generating it (block size: %d): %s",
+			defaultBlockSize,
+			config.SSHKey,
 		)
+
+		dir := filepath.Base(config.SSHKey)
+		err = os.MkdirAll(dir, 0644)
+		if err != nil {
+			return nil, karma.Format(
+				err,
+				"unable to make directory for ssh key: %s", dir,
+			)
+		}
+
+		err = sshkey.GeneratePair(config.SSHKey, defaultBlockSize)
 		if err != nil {
 			return nil, karma.Format(
 				err,
@@ -84,15 +108,71 @@ func LoadRunnerConfig(path string) (*RunnerConfig, error) {
 
 		log.Warningf(
 			nil,
-			"max_parallel_pipelines is not specified, number of cpu will be used instead: %d",
+			"max_parallel_pipelines is not specified, number of CPU will be used instead: %d",
 			config.MaxParallelPipelines,
 		)
 	}
 
+	if config.Name == "" {
+		hostname, err := os.Hostname()
+		if err != nil {
+			return nil, karma.Format(err, "unable to obtain hostname")
+		}
+
+		config.Name = hostname
+	}
+
 	return &config, nil
 }
 
 func isFileExists(path string) bool {
 	stat, err := os.Stat(path)
 	return !os.IsNotExist(err) && !stat.IsDir()
 }
+
+func showMessageNoConfiguration() {
+	fmt.Fprintln(os.Stderr, `
+
+ The snake-runner is ready to start but you have not provided address 
+ where you run Bitbucket server with Snake CI addon installed.
+ 
+ There are two ways to fix it:
+  1) specify master_address in your config file, by default it is /etc/snake-runner/snake-runner.conf
+  2) specify address using the environment variable SNAKE_MASTER_ADDRESS, like as following:
+   * SNAKE_MASTER_ADDRESS=http://mybitbucket.company/ snake-runner
+     or if you are running snake-runner in docker:
+   * docker run -e SNAKE_MASTER_ADDRESS=http://mybitbucket.company/ <other-docker-flags-here>
+
+ See also: <XXXXXXXXX>`)
+}
+
+func isDocker() bool {
+	contents, err := ioutil.ReadFile("/proc/1/cgroup")
+	if err != nil {
+		log.Errorf(err, "unable to read /proc/1/cgroup to determine "+
+			"is it docker container or not")
+	}
+
+	/**
+	* A docker container has /docker/ in its /cgroup file
+	*
+	* / # cat /proc/1/cgroup | grep docker
+	* 11:pids:/docker/14f3db3a669169c0b801a3ac99...
+	* 10:freezer:/docker/14f3db3a669169c0b801a3ac9...
+	* 9:cpu,cpuacct:/docker/14f3db3a669169c0b801a3ac...
+	* 8:hugetlb:/docker/14f3db3a669169c0b801a3ac99f89e...
+	* 7:perf_event:/docker/14f3db3a669169c0b801a3...
+	* 6:devices:/docker/14f3db3a669169c0b801a3ac99f...
+	* 5:memory:/docker/14f3db3a669169c0b801a3ac99f89e...
+	* 4:blkio:/docker/14f3db3a669169c0b801a3ac99f89e914...
+	* 3:cpuset:/docker/14f3db3a669169c0b801a3ac99f89e914a...
+	* 2:net_cls,net_prio:/docker/14f3db3a669169c0b801a3ac...
+	* 1:name=systemd:/docker/14f3db3a669169c0b801a3ac99f89e...
+	* 0::/system.slice/docker.service
+	***/
+	if strings.Contains(string(contents), "/docker/") {
+		return true
+	}
+
+	return false
+}

cmd/snake-runner/runner_register.go

@@ -44,7 +44,7 @@ func (runner *Runner) register() (string, error) {
 	}
 
 	request := requests.RunnerRegister{
-		Name:      runner.name,
+		Name:      runner.config.Name,
 		PublicKey: strings.TrimSpace(string(publicKey)),
 	}
 

cmd/snake-runner/scheduler.go

@@ -14,7 +14,7 @@ import (
 )
 
 func (runner *Runner) startScheduler() error {
-	docker, err := cloud.NewDocker()
+	docker, err := cloud.NewDocker(runner.config.DockerNetwork)
 	if err != nil {
 		return karma.Format(err, "unable to initialize container provider")
 	}

conf/snake-runner.conf

@@ -0,0 +1,30 @@
+# address of bitbucket server with Snake CI plugin installed
+# master_address: ""
+
+# log:
+#     debug: false
+#     trace: false
+
+# a custom name of runner, hostname is used as default
+# name: ""
+
+# specify custom runner token. you should never add it unless you are moving
+# your runner to another location and want to save it's id
+# token: ""
+
+# path to use to save token retrieved by master during registration
+# token_path: "/etc/snake-runner/token"
+
+# how often should runner let master know that it's online
+# heartbeat_interval: "30s"
+#
+# how often should runner ask for a job
+# heartbeat_interval: "5s"
+#
+# how many parallel pipelines can be running, 0 means to use number of CPUs
+# max_parallel_pipelines: 0
+#
+# path to ssh key that will be used for retrieving git repositories. it's not
+# required because snake-runner can generate it and send public part to Snake
+# CI plugin to add to repositories during job execution
+# ssh_key: "/etc/snake-runner/id_rsa"

docker/alpine.dockerfile

@@ -0,0 +1,23 @@
+FROM alpine:3
+
+COPY /snake-runner.docker /bin/snake-runner
+
+RUN  mkdir /etc/snake-runner/
+COPY /conf/snake-runner.conf /etc/snake-runner/snake-runner.conf
+
+ENV SNAKE_MASTER_ADDRESS         ""
+ENV SNAKE_LOG_DEBUG              ""
+ENV SNAKE_LOG_TRACE              ""
+ENV SNAKE_NAME                   ""
+ENV SNAKE_TOKEN                  ""
+ENV SNAKE_TOKEN_PATH             ""
+ENV SNAKE_VIRTUALIZATION         ""
+ENV SNAKE_MAX_PARALLEL_PIPELINES ""
+ENV SNAKE_SSH_KEY_PATH           ""
+
+VOLUME /var/run/docker.sock
+VOLUME /var/lib/snake-runner/secrets/
+
+CMD ["/bin/snake-runner"]
+
+# vim: ft=dockerfile

go.mod

@@ -18,6 +18,7 @@ require (
 	github.com/kovetskiy/ko v0.0.0-20200107130756-5aeb3d88d1de
 	github.com/kovetskiy/lorg v0.0.0-20200107130803-9a7136a95634 // indirect
 	github.com/kovetskiy/toml v0.2.0 // indirect
+	github.com/moby/moby v1.13.1
 	github.com/morikuni/aec v1.0.0 // indirect
 	github.com/opencontainers/go-digest v1.0.0-rc1 // indirect
 	github.com/opencontainers/image-spec v1.0.1 // indirect
@@ -30,7 +31,9 @@ require (
 	github.com/stretchr/testify v1.4.0
 	github.com/vmware/govmomi v0.22.1
 	github.com/zazab/zhash v0.0.0-20170403032415-ad45b89afe7a // indirect
+	golang.org/x/crypto v0.0.0-20191206172530-e9b2fee46413
 	golang.org/x/sys v0.0.0-20200116001909-b77594299b42 // indirect
+	gonum.org/v1/gonum v0.6.2
 	google.golang.org/api v0.15.0 // indirect
 	google.golang.org/grpc v1.26.0 // indirect
 	gopkg.in/yaml.v2 v2.2.7