Improved error handling, and error display in login form

app/pages/LoginPage.tsx

@@ -1,15 +1,17 @@
-import { AppState, injectState } from "@app/state";
-import log from "@common/logger";
 import { computed, observable } from "mobx";
 import { observer } from "mobx-react";
 import * as React from "react";
-import { Container, Dimmer, Form, Header, InputOnChangeData, Loader, Segment } from "semantic-ui-react";
+import { Container, Dimmer, Form, Header, InputOnChangeData, Loader, Message, Segment } from "semantic-ui-react";
+
+import { AppState, injectState } from "@app/state";
+import log from "@common/logger";
 
 class LoginPageState {
     @observable username = "";
     @observable password = "";
 
     @observable loading: boolean = false;
+    @observable error: string | null = null;
 
     @computed get canLogin() {
         return this.username.length > 0 && this.password.length > 0;
@@ -25,6 +27,7 @@ class LoginPageState {
 
     login(appState: AppState) {
         this.loading = true;
+        this.error = null;
         appState.tokenStore.grantPassword(this.username, this.password)
             .then(() => {
                 this.loading = false;
@@ -33,6 +36,7 @@ class LoginPageState {
             })
             .catch((err) => {
                 this.loading = false;
+                this.error = err.message;
                 log.error({ err }, "login error");
             });
     }
@@ -42,7 +46,7 @@ class LoginPage extends React.Component<{ appState: AppState }> {
     pageState = new LoginPageState();
 
     render() {
-        const { username, password, canLogin, loading } = this.pageState;
+        const { username, password, canLogin, loading, error } = this.pageState;
         return (
             <Container className="loginPage">
                 <Segment>
@@ -59,6 +63,7 @@ class LoginPage extends React.Component<{ appState: AppState }> {
                             type="password"
                             onChange={this.pageState.onPasswordChange}
                         />
+                        <Message error visible={error != null}>{error}</Message>
                         <Form.Button disabled={!canLogin} onClick={this.login}>Login</Form.Button>
                     </Form>
                 </Segment>

app/sprinklersRpc/websocketClient.ts

@@ -2,10 +2,10 @@ import { action, observable, when } from "mobx";
 import { update } from "serializr";
 
 import { TokenStore } from "@app/state/TokenStore";
+import { ErrorCode } from "@common/ErrorCode";
 import * as rpc from "@common/jsonRpc";
 import logger from "@common/logger";
 import * as deviceRequests from "@common/sprinklersRpc/deviceRequests";
-import { ErrorCode } from "@common/sprinklersRpc/ErrorCode";
 import * as s from "@common/sprinklersRpc/index";
 import * as schema from "@common/sprinklersRpc/schema/index";
 import { seralizeRequest } from "@common/sprinklersRpc/schema/requests";

app/state/HttpApi.ts

@@ -1,14 +1,8 @@
 import { TokenStore } from "@app/state/TokenStore";
+import ApiError from "@common/ApiError";
+import { ErrorCode } from "@common/ErrorCode";
 
-export class HttpApiError extends Error {
-    name = "HttpApiError";
-    status: number;
-
-    constructor(message: string, status: number = 500) {
-        super(message);
-        this.status = status;
-    }
-}
+export { ApiError };
 
 export default class HttpApi {
     baseUrl: string;
@@ -43,9 +37,14 @@ export default class HttpApi {
             ...options,
         };
         const response = await fetch(this.baseUrl + url, options);
-        const responseBody = await response.json() || {};
+        let responseBody: any;
+        try {
+            responseBody = await response.json() || {};
+        } catch (e) {
+            throw new ApiError("Invalid JSON response", ErrorCode.Internal, e);
+        }
         if (!response.ok) {
-            throw new HttpApiError(responseBody.message || response.statusText, response.status);
+            throw new ApiError(responseBody.message || response.statusText, responseBody.code, responseBody.data);
         }
         return responseBody;
     }

app/state/TokenStore.ts

@@ -1,8 +1,8 @@
 import { observable } from "mobx";
 
-import HttpApi, { HttpApiError } from "@app/state/HttpApi";
+import HttpApi, { ApiError } from "@app/state/HttpApi";
 import { Token } from "@app/state/Token";
-import { TokenGrantPasswordRequest, TokenGrantRefreshRequest, TokenGrantResponse } from "@common/http";
+import { TokenGrantPasswordRequest, TokenGrantRefreshRequest, TokenGrantResponse } from "@common/httpApi";
 import logger from "@common/logger";
 
 const log = logger.child({ source: "TokenStore"});
@@ -52,7 +52,7 @@ export class TokenStore {
 
     async grantRefresh() {
         if (!this.refreshToken.isValid) {
-            throw new HttpApiError("can not grant refresh with invalid refresh_token");
+            throw new ApiError("can not grant refresh with invalid refresh_token");
         }
         const request: TokenGrantRefreshRequest = {
             grant_type: "refresh", refresh_token: this.refreshToken.token!,

common/ApiError.ts

@@ -1,6 +1,6 @@
-import { ErrorCode, toHttpStatus } from "@common/sprinklersRpc/ErrorCode";
+import { ErrorCode, toHttpStatus } from "@common/ErrorCode";
 
-export class ApiError extends Error {
+export default class ApiError extends Error {
     name = "ApiError";
     statusCode: number;
     code: ErrorCode;

common/sprinklersRpc/websocketData.ts

@@ -1,7 +1,7 @@
 import * as rpc from "../jsonRpc/index";
 
+import { ErrorCode } from "@common/ErrorCode";
 import { Response as ResponseData } from "@common/sprinklersRpc/deviceRequests";
-import { ErrorCode } from "@common/sprinklersRpc/ErrorCode";
 
 export interface IAuthenticateRequest {
     accessToken: string;

server/express/authentication.ts

@@ -3,17 +3,16 @@ import Router from "express-promise-router";
 import * as jwt from "jsonwebtoken";
 
 import TokenClaims from "@common/TokenClaims";
-
 import {
     TokenGrantPasswordRequest,
     TokenGrantRefreshRequest,
     TokenGrantRequest,
     TokenGrantResponse,
-} from "@common/http";
-import { ErrorCode } from "@common/sprinklersRpc/ErrorCode";
+} from "@common/httpApi";
+import { ErrorCode } from "@common/ErrorCode";
 import { User } from "../models/User";
 import { ServerState } from "../state";
-import { ApiError } from "./errors";
+import ApiError from "@common/ApiError";
 
 export { TokenClaims };
 

server/express/errorHandler.ts

@@ -0,0 +1,14 @@
+import * as express from "express";
+
+import ApiError from "@common/ApiError";
+
+const errorHandler: express.ErrorRequestHandler =
+    (err: any, req: express.Request, res: express.Response, next: express.NextFunction) => {
+        if (err instanceof ApiError) {
+            res.status(err.statusCode).json(err.toJSON());
+        } else {
+            next(err);
+        }
+    };
+
+export default errorHandler;

server/express/index.ts

@@ -9,6 +9,7 @@ import serveApp from "./serveApp";
 
 import { User } from "../models/User";
 import { authentication } from "./authentication";
+import errorHandler from "./errorHandler";
 
 export function createApp(state: ServerState) {
     const app = express();
@@ -46,5 +47,7 @@ export function createApp(state: ServerState) {
 
     serveApp(app);
 
+    app.use(errorHandler);
+
     return app;
 }

server/sprinklersRpc/websocketServer.ts

@@ -5,7 +5,7 @@ import * as WebSocket from "ws";
 import * as rpc from "@common/jsonRpc";
 import log from "@common/logger";
 import * as deviceRequests from "@common/sprinklersRpc/deviceRequests";
-import { ErrorCode } from "@common/sprinklersRpc/ErrorCode";
+import { ErrorCode } from "@common/ErrorCode";
 import * as schema from "@common/sprinklersRpc/schema";
 import * as ws from "@common/sprinklersRpc/websocketData";
 import { TokenClaims, verifyToken } from "../express/authentication";