feat(motd): add the ability to display motd and dimiss information panels (#2191)

* feat(api): add motd handler

* feat(app): add the motd api layer

* feat(motd): display motd and add the ability to dismiss information messages

* style(home): relocate important message before info01

* feat(api): silently fail when an error occurs during motd retrieval

api/http/client/client.go

@@ -13,6 +13,10 @@ import (
 	"github.com/portainer/portainer"
 )
 
+const (
+	errInvalidResponseStatus = portainer.Error("Invalid response status (expecting 200)")
+)
+
 // HTTPClient represents a client to send HTTP requests.
 type HTTPClient struct {
 	*http.Client
@@ -75,6 +79,10 @@ func Get(url string) ([]byte, error) {
 	}
 	defer response.Body.Close()
 
+	if response.StatusCode != http.StatusOK {
+		return nil, errInvalidResponseStatus
+	}
+
 	body, err := ioutil.ReadAll(response.Body)
 	if err != nil {
 		return nil, err

api/http/handler/handler.go

@@ -10,6 +10,7 @@ import (
 	"github.com/portainer/portainer/http/handler/endpointproxy"
 	"github.com/portainer/portainer/http/handler/endpoints"
 	"github.com/portainer/portainer/http/handler/file"
+	"github.com/portainer/portainer/http/handler/motd"
 	"github.com/portainer/portainer/http/handler/registries"
 	"github.com/portainer/portainer/http/handler/resourcecontrols"
 	"github.com/portainer/portainer/http/handler/settings"
@@ -33,6 +34,7 @@ type Handler struct {
 	EndpointHandler        *endpoints.Handler
 	EndpointProxyHandler   *endpointproxy.Handler
 	FileHandler            *file.Handler
+	MOTDHandler            *motd.Handler
 	RegistryHandler        *registries.Handler
 	ResourceControlHandler *resourcecontrols.Handler
 	SettingsHandler        *settings.Handler
@@ -67,6 +69,8 @@ func (h *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		default:
 			http.StripPrefix("/api", h.EndpointHandler).ServeHTTP(w, r)
 		}
+	case strings.HasPrefix(r.URL.Path, "/api/motd"):
+		http.StripPrefix("/api", h.MOTDHandler).ServeHTTP(w, r)
 	case strings.HasPrefix(r.URL.Path, "/api/registries"):
 		http.StripPrefix("/api", h.RegistryHandler).ServeHTTP(w, r)
 	case strings.HasPrefix(r.URL.Path, "/api/resource_controls"):

api/http/handler/motd/handler.go

@@ -0,0 +1,24 @@
+package motd
+
+import (
+	"net/http"
+
+	"github.com/gorilla/mux"
+	"github.com/portainer/portainer/http/security"
+)
+
+// Handler is the HTTP handler used to handle MOTD operations.
+type Handler struct {
+	*mux.Router
+}
+
+// NewHandler returns a new Handler
+func NewHandler(bouncer *security.RequestBouncer) *Handler {
+	h := &Handler{
+		Router: mux.NewRouter(),
+	}
+	h.Handle("/motd",
+		bouncer.AuthenticatedAccess(http.HandlerFunc(h.motd))).Methods(http.MethodGet)
+
+	return h
+}

api/http/handler/motd/motd.go

@@ -0,0 +1,27 @@
+package motd
+
+import (
+	"net/http"
+
+	"github.com/portainer/portainer"
+	"github.com/portainer/portainer/crypto"
+	"github.com/portainer/portainer/http/client"
+	"github.com/portainer/portainer/http/response"
+)
+
+type motdResponse struct {
+	Message string `json:"Message"`
+	Hash    []byte `json:"Hash"`
+}
+
+func (handler *Handler) motd(w http.ResponseWriter, r *http.Request) {
+
+	motd, err := client.Get(portainer.MessageOfTheDayURL)
+	if err != nil {
+		w.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+
+	hash := crypto.HashFromBytes(motd)
+	response.JSON(w, &motdResponse{Message: string(motd), Hash: hash})
+}

api/http/server.go

@@ -11,6 +11,7 @@ import (
 	"github.com/portainer/portainer/http/handler/endpointproxy"
 	"github.com/portainer/portainer/http/handler/endpoints"
 	"github.com/portainer/portainer/http/handler/file"
+	"github.com/portainer/portainer/http/handler/motd"
 	"github.com/portainer/portainer/http/handler/registries"
 	"github.com/portainer/portainer/http/handler/resourcecontrols"
 	"github.com/portainer/portainer/http/handler/settings"
@@ -115,6 +116,8 @@ func (server *Server) Start() error {
 
 	var fileHandler = file.NewHandler(filepath.Join(server.AssetsPath, "public"))
 
+	var motdHandler = motd.NewHandler(requestBouncer)
+
 	var registryHandler = registries.NewHandler(requestBouncer)
 	registryHandler.RegistryService = server.RegistryService
 
@@ -175,6 +178,7 @@ func (server *Server) Start() error {
 		EndpointHandler:        endpointHandler,
 		EndpointProxyHandler:   endpointProxyHandler,
 		FileHandler:            fileHandler,
+		MOTDHandler:            motdHandler,
 		RegistryHandler:        registryHandler,
 		ResourceControlHandler: resourceControlHandler,
 		SettingsHandler:        settingsHandler,