server/camlistored: upload gpg key blob on startup

Fixes Issue #700

Change-Id: Ica92c321666220043e9c157de38e67a043250afe

pkg/jsonsign/signhandler/sig.go

@@ -125,7 +125,9 @@ func newJSONSignFromConfig(ld blobserver.Loader, conf jsonconfig.Obj) (http.Hand
 	return h, nil
 }
 
-func (h *Handler) uploadPublicKey() error {
+// UploadPublicKey writes the public key to the destination blobserver
+// defined for the handler, if needed.
+func (h *Handler) UploadPublicKey() error {
 	h.pubKeyUploadMu.RLock()
 	if h.pubKeyUploaded {
 		h.pubKeyUploadMu.RUnlock()
@@ -256,7 +258,7 @@ func (h *Handler) handleSign(rw http.ResponseWriter, req *http.Request) {
 		badReq(fmt.Sprintf("%v", err))
 		return
 	}
-	if err := h.uploadPublicKey(); err != nil {
+	if err := h.UploadPublicKey(); err != nil {
 		log.Printf("signing handler failed to upload public key: %v", err)
 	}
 	rw.Write([]byte(signedJSON))
@@ -282,7 +284,7 @@ func (h *Handler) Sign(bb *schema.Builder) (string, error) {
 	} else {
 		sreq.SignatureTime = claimTime
 	}
-	if err := h.uploadPublicKey(); err != nil {
+	if err := h.UploadPublicKey(); err != nil {
 		log.Printf("signing handler failed to upload public key: %v", err)
 	}
 	return sreq.Sign()

pkg/serverinit/serverinit.go

@@ -42,6 +42,7 @@ import (
 	"camlistore.org/pkg/blobserver/handlers"
 	"camlistore.org/pkg/httputil"
 	"camlistore.org/pkg/index"
+	"camlistore.org/pkg/jsonsign/signhandler"
 	"camlistore.org/pkg/osutil"
 	"camlistore.org/pkg/server"
 	"camlistore.org/pkg/server/app"
@@ -400,6 +401,10 @@ type Config struct {
 	// apps is the list of server apps configured during InstallHandlers,
 	// and that should be started after camlistored has started serving.
 	apps []*app.Handler
+	// signHandler is found and configured during InstallHandlers, or nil.
+	// It is stored in the Config, so we can call UploadPublicKey on on it as
+	// soon as camlistored is ready for it.
+	signHandler *signhandler.Handler
 }
 
 // detectConfigChange returns an informative error if conf contains obsolete keys.
@@ -587,6 +592,9 @@ func (config *Config) InstallHandlers(hi HandlerInstaller, baseURL string, reind
 		if helpHandler, ok := handler.(*server.HelpHandler); ok {
 			helpHandler.SetServerConfig(config.Obj)
 		}
+		if signHandler, ok := handler.(*signhandler.Handler); ok {
+			config.signHandler = signHandler
+		}
 		if in, ok := handler.(blobserver.HandlerIniter); ok {
 			if err := in.InitHandler(hl); err != nil {
 				return nil, fmt.Errorf("Error calling InitHandler on %s: %v", pfx, err)
@@ -618,6 +626,15 @@ func (config *Config) StartApps() error {
 	return nil
 }
 
+// UploadPublicKey uploads the public key blob with the sign handler that was
+// configured during InstallHandlers.
+func (config *Config) UploadPublicKey() error {
+	if config.signHandler == nil {
+		return nil
+	}
+	return config.signHandler.UploadPublicKey()
+}
+
 // AppURL returns a map of app name to app base URL for all the configured
 // server apps.
 func (config *Config) AppURL() map[string]string {

server/camlistored/camlistored.go

@@ -400,6 +400,10 @@ func Main(up chan<- struct{}, down <-chan struct{}) {
 		osutil.DieOnParentDeath()
 	}
 
+	if err := config.UploadPublicKey(); err != nil {
+		exitf("Error uploading public key on startup: %v", err)
+	}
+
 	if err := config.StartApps(); err != nil {
 		exitf("StartApps: %v", err)
 	}