AUTH-2993 added workers updater logic

cmd/cloudflared/updater/workers_service.go

@@ -0,0 +1,154 @@
+package updater
+
+import (
+	"encoding/json"
+	"errors"
+	"net/http"
+	"runtime"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// Options are the update options supported by the
+type Options struct {
+	// IsBeta is for beta updates to be installed if available
+	IsBeta bool
+
+	// IsForced is to forcibly download the latest version regardless of the current version
+	IsForced bool
+
+	// RequestedVersion is the specific version to upgrade or downgrade to
+	RequestedVersion string
+}
+
+// VersionResponse is the JSON response from the Workers API endpoint
+type VersionResponse struct {
+	URL          string `json:"url"`
+	Version      string `json:"version"`
+	Checksum     string `json:"checksum"`
+	IsCompressed bool   `json:"compressed"`
+	Error        string `json:"error"`
+}
+
+// WorkersService implements Service.
+// It contains everything needed to check in with the WorkersAPI and download and apply the updates
+type WorkersService struct {
+	currentVersion string
+	url            string
+	targetPath     string
+	opts           Options
+}
+
+// NewWorkersService creates a new updater Service object.
+func NewWorkersService(currentVersion, url, targetPath string, opts Options) Service {
+	return &WorkersService{
+		currentVersion: currentVersion,
+		url:            url,
+		targetPath:     targetPath,
+		opts:           opts,
+	}
+}
+
+// Check does a check in with the Workers API to get a new version update
+func (s *WorkersService) Check() (Version, error) {
+	client := &http.Client{
+		Timeout: time.Second * 5,
+	}
+
+	req, err := http.NewRequest(http.MethodGet, s.url, nil)
+	q := req.URL.Query()
+	q.Add(OSKeyName, runtime.GOOS)
+	q.Add(ArchitectureKeyName, runtime.GOARCH)
+
+	if s.opts.IsBeta {
+		q.Add(BetaKeyName, "true")
+	}
+
+	if s.opts.RequestedVersion != "" {
+		q.Add(VersionKeyName, s.opts.RequestedVersion)
+	}
+
+	req.URL.RawQuery = q.Encode()
+	resp, err := client.Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	var v VersionResponse
+	if err := json.NewDecoder(resp.Body).Decode(&v); err != nil {
+		return nil, err
+	}
+
+	if v.Error != "" {
+		return nil, errors.New(v.Error)
+	}
+
+	if !s.opts.IsForced && !IsNewerVersion(s.currentVersion, v.Version) {
+		return nil, nil
+	}
+
+	return NewWorkersVersion(v.URL, v.Version, v.Checksum, s.targetPath, v.IsCompressed), nil
+}
+
+// IsNewerVersion checks semantic versioning for the latest version
+// cloudflared tagging is more of a date than a semantic version,
+// but the same comparision logic still holds for major.minor.patch
+// e.g. 2020.8.2 is newer than 2020.8.1.
+func IsNewerVersion(current string, check string) bool {
+	if strings.Contains(strings.ToLower(current), "dev") {
+		return false // dev builds shouldn't update
+	}
+
+	cMajor, cMinor, cPatch, err := SemanticParts(current)
+	if err != nil {
+		return false
+	}
+
+	nMajor, nMinor, nPatch, err := SemanticParts(check)
+	if err != nil {
+		return false
+	}
+
+	if nMajor > cMajor {
+		return true
+	}
+
+	if nMajor == cMajor && nMinor > cMinor {
+		return true
+	}
+
+	if nMajor == cMajor && nMinor == cMinor && nPatch > cPatch {
+		return true
+	}
+	return false
+}
+
+// SemanticParts gets the major, minor, and patch version of a semantic version string
+// e.g. 3.1.2 would return 3, 1, 2, nil
+func SemanticParts(version string) (major int, minor int, patch int, err error) {
+	major = 0
+	minor = 0
+	patch = 0
+	parts := strings.Split(version, ".")
+	if len(parts) != 3 {
+		err = errors.New("invalid version")
+		return
+	}
+	major, err = strconv.Atoi(parts[0])
+	if err != nil {
+		return
+	}
+
+	minor, err = strconv.Atoi(parts[1])
+	if err != nil {
+		return
+	}
+
+	patch, err = strconv.Atoi(parts[2])
+	if err != nil {
+		return
+	}
+	return
+}