Add procs config field, add gitea act_runner example

.dockerignore

@@ -0,0 +1,8 @@
+Dockerfile
+.git
+autoscaler-proxy
+cloud-init.yml
+dev.env
+config.yml
+variables.yml
+TODO

.github/workflows/act_runner.yml

@@ -0,0 +1,43 @@
+name: Build act_runner image
+
+on:
+  push:
+    tags:
+      - '*'
+
+env:
+  REGISTRY: ghcr.io
+  IMAGE_NAME: ${{ github.repository }}
+
+jobs:
+  build-and-push-image:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Log in to the Container registry
+        uses: docker/[email protected]
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ github.token }}
+
+      - name: Extract metadata (tags, labels) for Docker
+        id: meta
+        uses: docker/[email protected]
+        with:
+          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+
+      - name: Build and push Docker image
+        uses: docker/[email protected]
+        with:
+          context: .
+          file: example/act_runner/Dockerfile
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}

.gitignore

@@ -1,6 +1,6 @@
 autoscaler-proxy
 cloud-init.yml
 dev.env
-config.yml
+/config.yml
 variables.yml
 TODO

README.md

@@ -9,7 +9,7 @@ The main motivation was to replace my drone.io setup that uses a [Hetzner autosc
 Test it with:
 
 ```
-HCLOUD_TOKEN=your_token go run .
+HCLOUD_TOKEN=your_token go run . example/docker/config.yml
 
 # New terminal window:
 DOCKER_HOST=tcp://127.0.0.1:8081 docker ps
@@ -44,21 +44,19 @@ autoscaler:
         name: autoscaler
         ssh_authorized_keys:
           - ${AUTOSCALER_AUTHORIZED_KEY}
-listen_addr:
-  127.0.0.1:8081:
-    net: unix
-    addr: /var/run/docker.sock
 ```
 
 If you haven't provided some of the fields, it will default to the values here.
 
 The configuration file supports some basic templating for the following variables:
 
-| Field                       | Description                                                 |
-| --------------------------- | ----------------------------------------------------------- |
-| `SERVER_RSA_PRIVATE`        | Private ssh key for the server, generated by the autoscaler |
-| `SERVER_RSA_PUBLIC`         | Public ssh key for the server, generated by the autoscaler  |
-| `AUTOSCALER_AUTHORIZED_KEY` | Public key of the autoscaler                                |
+| Field                       | Description                                                                               |
+| --------------------------- | ----------------------------------------------------------------------------------------- |
+| `SERVER_RSA_PRIVATE`        | Private ssh key for the server, generated by the autoscaler                               |
+| `SERVER_RSA_PUBLIC`         | Public ssh key for the server, generated by the autoscaler                                |
+| `AUTOSCALER_AUTHORIZED_KEY` | Public key of the autoscaler                                                              |
+| `AUTOSCALER_AUTHORIZED_KEY` | Public key of the autoscaler                                                              |
+| `env.[VARIABLE]`            | The value of the environment variable specified (from the process running the autoscaler) |
 
 You can also put key-value pairs in `autoscaler.cloud_init_variables` and reference them the same way. If you want to add some secrets you can create a yaml file with [sops](https://github.com/mozilla/sops) and put the file name in `autoscaler.cloud_init_variables_from`.
 
@@ -102,3 +100,9 @@ autoscaler:
 ```
 
 This would install tailscale and run `tailscale up` with an authkey from an encrypted file (secrets.yml). The autoscaler would wait until it was able to connect to `some_tailscale_ip:22` from the server before starting to proxy connections, so we know the server is fully configured and working as intended.
+
+There is also the option to configure `procs`, which lets you run other processes when starting this program. The processes are started when the server is ready to receive connections, and is stopped before shutting down the autoscaler. See example in `example/act_runner/config.yml`.
+
+## Autoscaling gitea runner
+
+There is a working example of an autoscaling gitea runner in `example/act_runner/`, it uses a "slightly patched" version of the runner and scales a server up when doing ci jobs, and down when idle.

autoscaler/cloud-init.go

@@ -36,7 +36,7 @@ func CreateCloudInitFile(template map[string]interface{}, opts AutoscalerOpts, s
 	variables["SERVER_RSA_PUBLIC"] = string(pubkeyBytes)
 	variables["AUTOSCALER_AUTHORIZED_KEY"] = string(authorizedKeyBytes)
 
-	config := utils.BuildTemplate(utils.TemplateMap(variables), template)
+	config := utils.BuildTemplate(utils.WithEnvMap(utils.TemplateMap(variables)), template)
 
 	d, err := yaml.Marshal(&config)
 

autoscaler/main.go

@@ -5,7 +5,6 @@ import (
 	"fmt"
 	"io"
 	"net"
-	"sync"
 	"time"
 
 	"github.com/JonasBak/autoscaler-proxy/utils"
@@ -15,8 +14,9 @@ import (
 var log = utils.Logger().WithField("pkg", "autoscaler")
 
 type UpstreamOpts struct {
-	Net  string `yaml:"net"`
-	Addr string `yaml:"addr"`
+	Net  string  `yaml:"net"`
+	Addr string  `yaml:"addr"`
+	Name *string `yaml:"name"`
 }
 
 type AutoscalerOpts struct {
@@ -73,7 +73,6 @@ func serverOptions(client *hcloud.Client, opts AutoscalerOpts, cloudInit string)
 
 type Autoscaler struct {
 	client     *hcloud.Client
-	mx         *sync.Mutex
 	server     *hcloud.Server
 	serverOpts hcloud.ServerCreateOpts
 
@@ -111,7 +110,6 @@ func New(opts AutoscalerOpts) Autoscaler {
 	serverOpts := serverOptions(client, opts, cloudInit)
 
 	as := Autoscaler{
-		mx:                new(sync.Mutex),
 		client:            client,
 		serverOpts:        serverOpts,
 		sshClient:         sshClient,
@@ -183,9 +181,6 @@ func (as *Autoscaler) evaluateScaledown(ctx context.Context) error {
 		return nil
 	}
 
-	as.mx.Lock()
-	defer as.mx.Unlock()
-
 	timeSinceLastInteraction := time.Now().Sub(as.lastInteraction)
 
 	log.WithField("time_since_last_interaction", timeSinceLastInteraction.String()).Debug("Evaluating scaledown")
@@ -203,8 +198,6 @@ func (as *Autoscaler) evaluateScaledown(ctx context.Context) error {
 // other should use EnsureOnline.
 func (as *Autoscaler) ensureOnline(ctx context.Context) error {
 	log.Debug("Making sure server is online")
-	as.mx.Lock()
-	defer as.mx.Unlock()
 
 	as.lastInteraction = time.Now()
 
@@ -297,8 +290,6 @@ LOOP:
 			}
 			break
 		case c := <-as.cShutdown:
-			as.mx.Lock()
-			defer as.mx.Unlock()
 			c <- as.deleteServer()
 			break LOOP
 		}

config.go

@@ -1,11 +1,13 @@
 package main
 
 import (
+	"fmt"
 	"os"
 	"time"
 
 	as "github.com/JonasBak/autoscaler-proxy/autoscaler"
 	"github.com/JonasBak/autoscaler-proxy/proxy"
+	"github.com/JonasBak/autoscaler-proxy/utils"
 	"gopkg.in/yaml.v3"
 )
 
@@ -38,13 +40,20 @@ func DefaultConfig() proxy.ProxyOpts {
 			},
 			CloudInitVariables: map[string]string{},
 		},
-		ListenAddr: map[string]as.UpstreamOpts{
-			"127.0.0.1:8081": {
-				Net:  "unix",
-				Addr: "/var/run/docker.sock",
-			},
-		},
+		ListenAddr: map[string]as.UpstreamOpts{},
+	}
+}
+
+func patchProcsOpts(opts proxy.ProxyOpts) proxy.ProxyOpts {
+	variables := make(map[string]string)
+	for addr, upstream := range opts.ListenAddr {
+		if upstream.Name != nil {
+			variables[fmt.Sprintf("autoscaler.listen.%s", *upstream.Name)] = addr
+		}
 	}
+	env := utils.BuildTemplate(utils.TemplateMap(variables), opts.Procs.Env).(map[string]string)
+	opts.Procs.Env = env
+	return opts
 }
 
 func ParseConfigFile(path string) (proxy.ProxyOpts, error) {
@@ -59,9 +68,7 @@ func ParseConfigFile(path string) (proxy.ProxyOpts, error) {
 		return opts, err
 	}
 
-	if opts.Autoscaler.HCloudToken == "" {
-		opts.Autoscaler.HCloudToken = os.Getenv("HCLOUD_TOKEN")
-	}
+	opts = patchProcsOpts(opts)
 
 	return opts, nil
 }

example/act_runner/Dockerfile

@@ -0,0 +1,36 @@
+FROM golang:1.21-alpine as runner
+
+WORKDIR /build
+
+RUN apk add make git
+
+RUN git clone https://gitea.com/gitea/act_runner.git . && git reset --hard d07fbfc8c3
+
+COPY ./example/act_runner/docker-client-ping.patch .
+
+RUN git apply docker-client-ping.patch
+
+RUN make build
+
+FROM golang:1.21-alpine as proxy
+
+WORKDIR /build
+
+COPY . .
+
+RUN go build .
+
+FROM alpine
+
+RUN mkdir /app /data && chown 10000:10000 /app /data
+
+USER 10000
+
+WORKDIR /data
+
+COPY --from=runner /build/act_runner /usr/bin/act_runner
+COPY --from=proxy /build/autoscaler-proxy /usr/bin/autoscaler-proxy
+
+COPY ./example/act_runner/config.yml /app/config.yml
+
+ENTRYPOINT ["autoscaler-proxy", "/app/config.yml"]

example/act_runner/config.yml

@@ -0,0 +1,12 @@
+listen_addr:
+  127.0.0.1:8081:
+    net: unix
+    addr: /var/run/docker.sock
+    name: docker
+procs:
+  env:
+    GITEA_INSTANCE: "${env.GITEA_INSTANCE}"
+    GITEA_TOKEN: "${env.GITEA_TOKEN}"
+    DOCKER_HOST: "tcp://${autoscaler.listen.docker}"
+  run:
+    - test -f .runner || act_runner register --instance $GITEA_INSTANCE --token $GITEA_TOKEN --no-interactive; act_runner daemon

example/act_runner/docker-client-ping.patch

@@ -0,0 +1,55 @@
+diff --git a/internal/pkg/envcheck/docker.go b/internal/pkg/envcheck/docker.go
+index 0a634ad..173b53a 100644
+--- a/internal/pkg/envcheck/docker.go
++++ b/internal/pkg/envcheck/docker.go
+@@ -5,30 +5,30 @@ package envcheck
+
+ import (
+ 	"context"
+-	"fmt"
++	// "fmt"
+
+-	"github.com/docker/docker/client"
++	// "github.com/docker/docker/client"
+ )
+
+ func CheckIfDockerRunning(ctx context.Context, configDockerHost string) error {
+-	opts := []client.Opt{
+-		client.FromEnv,
+-	}
+-
+-	if configDockerHost != "" {
+-		opts = append(opts, client.WithHost(configDockerHost))
+-	}
+-
+-	cli, err := client.NewClientWithOpts(opts...)
+-	if err != nil {
+-		return err
+-	}
+-	defer cli.Close()
+-
+-	_, err = cli.Ping(ctx)
+-	if err != nil {
+-		return fmt.Errorf("cannot ping the docker daemon, does it running? %w", err)
+-	}
++	// opts := []client.Opt{
++	// 	client.FromEnv,
++	// }
++
++	// if configDockerHost != "" {
++	// 	opts = append(opts, client.WithHost(configDockerHost))
++	// }
++
++	// cli, err := client.NewClientWithOpts(opts...)
++	// if err != nil {
++	// 	return err
++	// }
++	// defer cli.Close()
++
++	// _, err = cli.Ping(ctx)
++	// if err != nil {
++	// 	return fmt.Errorf("cannot ping the docker daemon, does it running? %w", err)
++	// }
+
+ 	return nil
+ }

example/docker/config.yml

@@ -0,0 +1,4 @@
+listen_addr:
+  127.0.0.1:8081:
+    net: unix
+    addr: /var/run/docker.sock

main.go

@@ -21,6 +21,10 @@ func main() {
 		}
 		config = c
 	}
+	if config.Autoscaler.HCloudToken == "" {
+		config.Autoscaler.HCloudToken = os.Getenv("HCLOUD_TOKEN")
+	}
+
 	p := proxy.New(config)
 
 	ctx, cancel := context.WithCancel(context.Background())
@@ -29,7 +33,7 @@ func main() {
 
 	go func() {
 		c := make(chan os.Signal, 1)
-		signal.Notify(c, os.Kill, syscall.SIGTERM)
+		signal.Notify(c, syscall.SIGTERM)
 		<-c
 		log.Warn("Killing...")
 		p.Kill()