* added HETZNER_SERVER_IMAGE

* added HETZNER_SERVER_LOCATION
* added HETZNER_SERVER_MAX
* added HETZNER_SERVER_MIN
* added HETZNER_SERVER_TYPE
* exposing SCALER_POLL_INTERVAL in Dockerfile
* now logging error instead of quitting program
* added support for newer woodpecker server version 1.0.x

Dockerfile

@@ -9,9 +9,15 @@ COPY --from=builder /jynx/jynx /jynx
 COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/
 ENTRYPOINT ["/jynx"]
 
-ENV HCLOUD_API_TOKEN=""
-ENV WOODPECKER_HOSTNAME=""
-ENV WOODPECKER_AGENT_SECRET=""
-ENV HCLOUD_PREFIX=""
-ENV WOODPECKER_PROMETHEUS_AUTH_TOKEN=""
+ENV HETZNER_CLOUD_API_TOKEN=""
+ENV HETZNER_CLOUD_PREFIX=""
+ENV HETZNER_SERVER_IMAGE=""
+ENV HETZNER_SERVER_LOCATION=""
+ENV HETZNER_SERVER_MAX=""
+ENV HETZNER_SERVER_MIN=""
+ENV HETZNER_SERVER_TYPE=""
 ENV LOGLEVEL=""
+ENV SCALER_POLL_INTERVAL=""
+ENV WOODPECKER_AGENT_SECRET=""
+ENV WOODPECKER_HOSTNAME=""
+ENV WOODPECKER_PROMETHEUS_AUTH_TOKEN=""

backend/hetzner/servers.go

@@ -22,12 +22,7 @@ type VersionInfo struct {
 }
 
 func connect() *hcloud.Client {
-	token := os.Getenv("HCLOUD_API_TOKEN")
-	if token == "" {
-		log.PrintError("please specify HCLOUD_API_TOKEN")
-		os.Exit(1)
-	}
-	return hcloud.NewClient(hcloud.WithToken(token))
+	return hcloud.NewClient(hcloud.WithToken(os.Getenv("HETZNER_CLOUD_API_TOKEN")))
 }
 
 func GetNewSuffix(servers []*hcloud.Server) (int, error) {
@@ -100,7 +95,7 @@ func CheckServerDeletions(servers []*hcloud.Server) error {
 		pollIntervalSeconds %= 3600
 	}
 
-	for _, server := range servers {
+	for i, server := range servers {
 		safeInterval := time.Duration(3600-pollIntervalSeconds) * time.Second
 		optimalDeleteTime := server.Created.Add(safeInterval).Local()
 		log.PrintDebug(server.Name, "optimal delete time:", optimalDeleteTime)
@@ -108,6 +103,21 @@ func CheckServerDeletions(servers []*hcloud.Server) error {
 			continue
 		}
 
+		// check if HETZNER_SERVER_MIN was provided as an environment variable
+		if minServersString := os.Getenv("HETZNER_SERVER_MIN"); minServersString != "" {
+			minServers, err := strconv.Atoi(minServersString)
+			if err != nil {
+				return err
+			}
+
+			// if the amount of servers is less than the minimal amount required
+			// leave this server running
+			if i < minServers {
+				log.PrintDebug("not deleting server", server.Name, "because HETZNER_SERVER_MIN is", minServers)
+				continue
+			}
+		}
+
 		// optimal delete time has passed, delete the server
 		if err := DeleteServer(server); err != nil {
 			return err
@@ -199,16 +209,31 @@ func CreateServers(servers []string) error {
 			return nil
 		}
 
+		// get location and server type from environment
+		serverImage := os.Getenv("HETZNER_SERVER_IMAGE")
+		serverLocation := os.Getenv("HETZNER_SERVER_LOCATION")
+		serverType := os.Getenv("HETZNER_SERVER_TYPE")
+
+		// set default values for servers if none were provided
+		switch "" {
+		case serverImage:
+			serverImage = "docker-ce"
+		case serverLocation:
+			serverLocation = "fsn1"
+		case serverType:
+			serverType = "cax11"
+		}
+
 		serverOpts := hcloud.ServerCreateOpts{
-			Name:             server,
-			StartAfterCreate: hcloud.Ptr(true),
-			SSHKeys:          sshkeys,
-			Image:            &hcloud.Image{Name: "docker-ce"},
-			ServerType:       &hcloud.ServerType{Name: "cax11"},
-			Location:         &hcloud.Location{Name: "fsn1"},
-			UserData:         userdata,
-			PublicNet:        &hcloud.ServerCreatePublicNet{EnableIPv4: true},
+			Image:            &hcloud.Image{Name: serverImage},
 			Labels:           labels,
+			Location:         &hcloud.Location{Name: serverLocation},
+			Name:             server,
+			PublicNet:        &hcloud.ServerCreatePublicNet{EnableIPv4: true},
+			SSHKeys:          sshkeys,
+			ServerType:       &hcloud.ServerType{Name: serverType},
+			StartAfterCreate: hcloud.Ptr(true),
+			UserData:         userdata,
 		}
 		_, _, err = client.Server.Create(context.Background(), serverOpts)
 		if err != nil {

ci/woodpecker/woodpecker.go

@@ -61,7 +61,7 @@ func (s Server) GetStats() (*Stats, error) {
 
 	lines := strings.Split(string(b), "\n")
 
-	r := regexp.MustCompile(`^((woodpecker_)(worker_count|pending_jobs|running_jobs)) (\d+)`)
+	r := regexp.MustCompile(`^((woodpecker_)(worker_count|pending_jobs|pending_steps|running_jobs|running_steps)) (\d+)`)
 
 	var stats Stats
 
@@ -76,9 +76,9 @@ func (s Server) GetStats() (*Stats, error) {
 
 		// assign stats to struct
 		switch matches[3] {
-		case "pending_jobs":
+		case "pending_jobs", "pending_steps":
 			stats.PendingJobs = parseStringToInt(matches[4])
-		case "running_jobs":
+		case "running_jobs", "running_steps":
 			stats.RunningJobs = parseStringToInt(matches[4])
 		case "worker_count":
 			stats.IdlingWorkers = parseStringToInt(matches[4])

main.go

@@ -35,13 +35,13 @@ func main() {
 
 	// start scaler once
 	if err := scaler.Start(&w); err != nil {
-		panic(err)
+		log.PrintError(err)
 	}
 
 	// start scaler every tick
 	for range ticker {
 		if err := scaler.Start(&w); err != nil {
-			panic(err)
+			log.PrintError(err)
 		}
 	}
 }
@@ -50,18 +50,18 @@ func checkEnv() {
 	switch "" {
 	case os.Getenv("WOODPECKER_HOSTNAME"):
 		log.PrintError("WOODPECKER_HOSTNAME not set")
+		os.Exit(1)
 	case os.Getenv("WOODPECKER_AGENT_SECRET"):
 		log.PrintError("WOODPECKER_AGENT_SECRET not set")
 		os.Exit(1)
-	case os.Getenv("HCLOUD_PREFIX"):
-		log.PrintError("HCLOUD_PREFIX not set")
-		os.Exit(1)
 	case os.Getenv("WOODPECKER_PROMETHEUS_AUTH_TOKEN"):
 		log.PrintError("WOODPECKER_PROMETHEUS_AUTH_TOKEN not set")
 		os.Exit(1)
 	case os.Getenv("HETZNER_SSH_KEY_NAMES"):
 		log.PrintError("HETZNER_SSH_KEY_NAMES not set")
 		os.Exit(1)
+	case os.Getenv("HETZNER_CLOUD_API_TOKEN"):
+		log.PrintError("please specify HETZNER_CLOUD_API_TOKEN")
+		os.Exit(1)
 	}
-
 }

scaler/scaler.go

@@ -3,6 +3,7 @@ package scaler
 import (
 	"fmt"
 	"os"
+	"strconv"
 
 	"git.stinnesbeck.com/go/jynx/backend/hetzner"
 	"git.stinnesbeck.com/go/jynx/ci/woodpecker"
@@ -16,7 +17,12 @@ func Start(w *woodpecker.Server) error {
 	}
 
 	// get the prefix for jynx managed servers
-	prefix := os.Getenv("HCLOUD_PREFIX")
+	prefix := os.Getenv("HETZNER_CLOUD_PREFIX")
+
+	// set default prefix if none was provided
+	if prefix == "" {
+		prefix = "jynx"
+	}
 
 	// get a list of all servers from hetzner (from jynx)
 	servers, err := hetzner.ListJynxServers(prefix)
@@ -51,14 +57,26 @@ func Start(w *woodpecker.Server) error {
 		return nil
 	}
 
-	// there are servers to be created
+	if maxServersString := os.Getenv("HETZNER_SERVER_MAX"); maxServersString != "" {
+		maxServers, err := strconv.Atoi(maxServersString)
+		if err != nil {
+			return err
+		}
+		// check if the maximum amount of servers is reached if one is provided
+		if newServers+len(servers) > maxServers && maxServers != 0 {
+			newServers = maxServers - len(servers)
+		}
+	}
 
+	// if there are no servers to be created, exit here
 	if newServers < 1 {
 		return nil
 	}
 
+	// slice to hold servers to be created
 	var ScaleUpServers []string
 
+	// there are servers to be created
 	// get the suffix for the starting server
 	suffix, err := hetzner.GetNewSuffix(servers)
 	for i := 0; i < newServers; i++ {