added automagical detection of woodpecker server version

backend/hetzner/servers.go

@@ -2,7 +2,10 @@ package hetzner
 
 import (
 	"context"
+	"encoding/json"
 	"fmt"
+	"io"
+	"net/http"
 	"os"
 	"regexp"
 	"strconv"
@@ -13,6 +16,11 @@ import (
 	"github.com/hetznercloud/hcloud-go/hcloud"
 )
 
+type VersionInfo struct {
+	Source  string `json:"source"`
+	Version string `json:"version"`
+}
+
 func connect() *hcloud.Client {
 	token := os.Getenv("HCLOUD_API_TOKEN")
 	if token == "" {
@@ -130,9 +138,10 @@ func CreateServers(servers []string) error {
 	// read in some environment variables
 	agentSecret := os.Getenv("WOODPECKER_AGENT_SECRET")
 	r := regexp.MustCompile(`http[s]*:\/\/(.*)`)
+	woodpeckerHostname := os.Getenv("WOODPECKER_HOSTNAME")
 	hasPort := regexp.MustCompile(`^.*(:\d+)`)
 	withoutPort := regexp.MustCompile(`^https?:\/\/(.*):`)
-	woodpeckerHost := r.FindStringSubmatch(os.Getenv("WOODPECKER_HOSTNAME"))[1]
+	woodpeckerHost := r.FindStringSubmatch(woodpeckerHostname)[1]
 	if hasPort.MatchString(woodpeckerHost) {
 		woodpeckerHost = withoutPort.FindStringSubmatch(woodpeckerHost)[1]
 	}
@@ -146,10 +155,36 @@ func CreateServers(servers []string) error {
 	}
 	woodpeckerHost += ":" + statsPort
 
+	// get woodpecker server version
+	// prepare request
+	req, err := http.NewRequest(http.MethodGet, woodpeckerHostname+"/version", nil)
+	if err != nil {
+		return err
+	}
+
+	c := http.DefaultClient
+	response, err := c.Do(req)
+	if err != nil {
+		return err
+	}
+
+	b, err := io.ReadAll(response.Body)
+	if err != nil {
+		return err
+	}
+
+	var version VersionInfo
+
+	err = json.Unmarshal(b, &version)
+
+	if err != nil {
+		return err
+	}
+
 	// loop through each server
 	for _, server := range servers {
 		// create unique AgentCMD for cloud init
-		AgentCMD := fmt.Sprintf("docker run -d -v /var/run/docker.sock:/var/run/docker.sock -e WOODPECKER_GRPC_SECURE=false -e WOODPECKER_SERVER=%s -e WOODPECKER_AGENT_SECRET=%s -e WOODPECKER_MAX_PROCS=%d -e WOODPECKER_HOSTNAME=%s woodpeckerci/woodpecker-agent", woodpeckerHost, agentSecret, 1, server)
+		AgentCMD := fmt.Sprintf("docker run -d -v /var/run/docker.sock:/var/run/docker.sock -e WOODPECKER_GRPC_SECURE=false -e WOODPECKER_SERVER=%s -e WOODPECKER_AGENT_SECRET=%s -e WOODPECKER_MAX_PROCS=%d -e WOODPECKER_HOSTNAME=%s woodpeckerci/woodpecker-agent:v"+version.Version, woodpeckerHost, agentSecret, 1, server)
 
 		userdata := fmt.Sprintf("#cloud-config\nruncmd:\n  - %s", AgentCMD)
 		labels := make(map[string]string)