From 00f7ca72a55563ee52822587a7caebbd92804842 Mon Sep 17 00:00:00 2001
From: hippoz <10706925-hippoz@users.noreply.gitlab.com>
Date: Sun, 23 Jul 2023 05:06:07 +0300
Subject: [PATCH] add error handling for failed requests

---
 .../components/overlays/AddCommunity.svelte   |  16 +-
 .../components/overlays/CreateAccount.svelte  |  16 +-
 .../components/overlays/CreateChannel.svelte  |  16 +-
 .../components/overlays/EditChannel.svelte    |  22 ++-
 .../components/overlays/EditMessage.svelte    |  21 ++-
 frontend/src/components/overlays/Login.svelte |  22 +--
 .../src/components/rpc/RpcErrorDisplay.svelte |  41 +++++
 frontend/src/request.js                       | 167 +++++++++++++-----
 frontend/src/stores.js                        |  18 +-
 9 files changed, 233 insertions(+), 106 deletions(-)
 create mode 100644 frontend/src/components/rpc/RpcErrorDisplay.svelte

diff --git a/frontend/src/components/overlays/AddCommunity.svelte b/frontend/src/components/overlays/AddCommunity.svelte
index 6410691..a779dd8 100644
--- a/frontend/src/components/overlays/AddCommunity.svelte
+++ b/frontend/src/components/overlays/AddCommunity.svelte
@@ -1,19 +1,19 @@
 <script>
-    import { overlayStore } from "../../stores";
-    import { methods, remoteSignal } from "../../request";
+    import { methods, remoteSignal, responseOk } from "../../request";
+    import RpcErrorDisplay from "../rpc/RpcErrorDisplay.svelte";
     import Modal from "./Modal.svelte";
 
     let communityName = "";
     let createButtonEnabled = true;
+    let response;
     export let close = () => {};
 
     const create = async () => {
         createButtonEnabled = false;
-        const { ok } = await remoteSignal(methods.createCommunity, communityName);
-        if (!ok) {
-            overlayStore.toast("Couldn't create community");
-        }
-        close();
+        response = await remoteSignal(methods.createCommunity, communityName);
+        createButtonEnabled = true;
+        if (responseOk(response))
+            close();
     };
 </script>
 
@@ -21,6 +21,8 @@
     <span class="h4" slot="header">Create Community</span>
 
     <svelte:fragment slot="content">
+        <RpcErrorDisplay response={response} />
+        <RpcErrorDisplay validationIndex={0} response={response} />
         <label class="input-label">
             Community Name
             <input class="input full-width" minlength="1" maxlength="32" bind:value={ communityName } />
diff --git a/frontend/src/components/overlays/CreateAccount.svelte b/frontend/src/components/overlays/CreateAccount.svelte
index ba0401e..e22d311 100644
--- a/frontend/src/components/overlays/CreateAccount.svelte
+++ b/frontend/src/components/overlays/CreateAccount.svelte
@@ -1,24 +1,24 @@
 <script>
     import { overlayStore, OverlayType } from "../../stores";
-    import { methods, remoteCall } from "../../request";
+    import { methods, remoteCall, responseOk } from "../../request";
     import Modal from "./Modal.svelte";
+    import RpcErrorDisplay from "../rpc/RpcErrorDisplay.svelte";
 
     let username = "";
     let password = "";
     let buttonsEnabled = true;
     let pendingOtherOpen = false;
+    let response;
     export let close = () => {};
 
     const create = async () => {
         buttonsEnabled = false;
-        const { ok } = await remoteCall(methods.createUser, username, password);
-        if (ok) {
+        response = await remoteCall(methods.createUser, username, password);
+        if (responseOk(response)) {
             overlayStore.toast("Account created");
             loginInstead();
         } else {
-            overlayStore.toast("Couldn't create account");
             buttonsEnabled = true;
-            return;
         }
     };
     const loginInstead = () => {
@@ -42,6 +42,9 @@
     <span class="h4" slot="header">Create an Account</span>
 
     <svelte:fragment slot="content">
+        <RpcErrorDisplay response={response} />
+
+        <RpcErrorDisplay validationIndex={0} response={response} />
         <label class="input-label">
             Username
             <input class="input full-width" minlength="1" maxlength="32" bind:value={ username } />
@@ -49,6 +52,7 @@
 
         <div class="separator" />
 
+        <RpcErrorDisplay validationIndex={1} response={response} />
         <label class="input-label">
             Password
             <input class="input full-width" minlength="8" type="password" bind:value={ password } />
@@ -56,7 +60,7 @@
     </svelte:fragment>
 
     <svelte:fragment slot="footer">
-        <button class="button modal-secondary-action" on:click="{ loginInstead }">Log in instead</button>
+        <button class="button modal-secondary-action" on:click="{ loginInstead }" disabled="{ !buttonsEnabled }">Log in instead</button>
         <button class="button button-accent modal-primary-action" on:click="{ create }" disabled="{ !buttonsEnabled }">Create</button>
     </svelte:fragment>
 </Modal>
diff --git a/frontend/src/components/overlays/CreateChannel.svelte b/frontend/src/components/overlays/CreateChannel.svelte
index bb43b6f..8b44021 100644
--- a/frontend/src/components/overlays/CreateChannel.svelte
+++ b/frontend/src/components/overlays/CreateChannel.svelte
@@ -1,20 +1,20 @@
 <script>
-    import { overlayStore } from "../../stores";
-    import { methods, remoteSignal } from "../../request";
+    import { methods, remoteSignal, responseOk } from "../../request";
+    import RpcErrorDisplay from "../rpc/RpcErrorDisplay.svelte";
     import Modal from "./Modal.svelte";
 
     let channelName = "";
     let createButtonEnabled = true;
+    let response;
     export let close = () => {};
     export let community = null;
 
     const create = async () => {
         createButtonEnabled = false;
-        const { ok } = await remoteSignal(methods.createChannel, channelName, community.id !== -1 ? community.id : null);
-        if (!ok) {
-            overlayStore.toast("Couldn't create channel");
-        }
-        close();
+        response = await remoteSignal(methods.createChannel, channelName, community.id !== -1 ? community.id : null);
+        createButtonEnabled = true;
+        if (responseOk(response))
+            close();
     };
 </script>
 
@@ -27,6 +27,8 @@
     </svelte:fragment>
 
     <svelte:fragment slot="content">
+        <RpcErrorDisplay response={response} />
+        <RpcErrorDisplay validationIndex={0} response={response} />
         <label class="input-label">
             Channel Name
             <input class="input full-width" minlength="1" maxlength="32" bind:value={ channelName } />
diff --git a/frontend/src/components/overlays/EditChannel.svelte b/frontend/src/components/overlays/EditChannel.svelte
index d104af8..ebd71c6 100644
--- a/frontend/src/components/overlays/EditChannel.svelte
+++ b/frontend/src/components/overlays/EditChannel.svelte
@@ -1,27 +1,29 @@
 <script>
     import { overlayStore } from "../../stores";
-    import { methods, remoteSignal } from "../../request";
+    import { getMessageFromResponse, methods, remoteSignal, responseOk } from "../../request";
     import Modal from "./Modal.svelte";
+    import RpcErrorDisplay from "../rpc/RpcErrorDisplay.svelte";
 
     export let channel;
 
     let channelName = channel.name;
     let buttonsEnabled = true;
+    let response;
     export let close = () => {};
 
     const save = async () => {
         buttonsEnabled = false;
-        const { ok } = await remoteSignal(methods.updateChannelName, channel.id, channelName);
-        if (!ok) {
-            overlayStore.toast("Couldn't edit channel");
+        response = await remoteSignal(methods.updateChannelName, channel.id, channelName);
+        buttonsEnabled = true;
+        if (responseOk(response)) {
+            close();
         }
-        close();
     };
     const deleteChannel = async () => {
         buttonsEnabled = false;
-        const { ok } = await remoteSignal(methods.deleteChannel, channel.id);
-        if (!ok) {
-            overlayStore.toast("Couldn't delete channel");
+        const res = await remoteSignal(methods.deleteChannel, channel.id);
+        if (!responseOk(res)) {
+            overlayStore.toast(`Couldn't delete channel: ${getMessageFromResponse(res)}`);
         }
         close();
     };
@@ -37,8 +39,10 @@
     <span class="h4" slot="header">Edit Channel</span>
 
     <svelte:fragment slot="content">
+        <RpcErrorDisplay response={response} />
+        <RpcErrorDisplay validationIndex={1} response={response} />
         <label class="input-label">
-            Channel Name
+            <span>Channel Name</span>
             <input class="input full-width" minlength="1" maxlength="32" bind:value={ channelName } />
         </label>
     </svelte:fragment>
diff --git a/frontend/src/components/overlays/EditMessage.svelte b/frontend/src/components/overlays/EditMessage.svelte
index f8ff1df..2ea0752 100644
--- a/frontend/src/components/overlays/EditMessage.svelte
+++ b/frontend/src/components/overlays/EditMessage.svelte
@@ -1,27 +1,28 @@
 <script>
     import { overlayStore } from "../../stores";
-    import { methods, remoteSignal } from "../../request";
+    import { getMessageFromResponse, methods, remoteSignal, responseOk } from "../../request";
     import Modal from "./Modal.svelte";
+    import RpcErrorDisplay from "../rpc/RpcErrorDisplay.svelte";
 
     export let message;
 
     let messageContent = message.content;
     let buttonsEnabled = true;
+    let response;
     export let close = () => {};
 
     const save = async () => {
         buttonsEnabled = false;
-        const { ok } = await remoteSignal(methods.updateMessageContent, message.id, messageContent);
-        if (!ok) {
-            overlayStore.toast("Couldn't edit message");
-        }
-        close();
+        response = await remoteSignal(methods.updateMessageContent, message.id, messageContent);
+        buttonsEnabled = true;
+        if (responseOk(response))
+            close();
     };
     const deleteMessage = async () => {
         buttonsEnabled = false;
-        const { ok } = await remoteSignal(methods.deleteMessage, message.id);
-        if (!ok) {
-            overlayStore.toast("Couldn't delete message");
+        const res = await remoteSignal(methods.deleteMessage, message.id);
+        if (!responseOk(res)) {
+            overlayStore.toast(`Couldn't delete message: ${getMessageFromResponse(res)}`);
         }
         close();
     };
@@ -37,6 +38,8 @@
     <span class="h4" slot="header">Edit Message</span>
 
     <svelte:fragment slot="content">
+        <RpcErrorDisplay response={response} />
+        <RpcErrorDisplay validationIndex={1} response={response} />
         <label class="input-label">
             Content
             <input class="input full-width" minlength="1" bind:value={ messageContent } />
diff --git a/frontend/src/components/overlays/Login.svelte b/frontend/src/components/overlays/Login.svelte
index 27aaf14..1c90305 100644
--- a/frontend/src/components/overlays/Login.svelte
+++ b/frontend/src/components/overlays/Login.svelte
@@ -1,29 +1,25 @@
 <script>
     import { overlayStore, OverlayType } from "../../stores";
-    import { remoteCall } from "../../request";
+    import { remoteCall, responseOk } from "../../request";
     import { authWithToken } from "../../auth";
     import { methods } from "../../request";
     import Modal from "./Modal.svelte";
+    import RpcErrorDisplay from "../rpc/RpcErrorDisplay.svelte";
 
     let username = "";
     let password = "";
     let buttonsEnabled = true;
     let pendingOtherOpen = false;
+    let response;
     export let close = () => {};
 
     const login = async () => {
         buttonsEnabled = false;
-        const { ok, json } = await remoteCall(methods.loginUser, username, password);
-        if (ok && json && json.token) {
-            authWithToken(json.token, true);
+        response = await remoteCall(methods.loginUser, username, password);
+        if (responseOk(response) && response.data && response.data.token) {
+            authWithToken(response.data.token, true);
         } else {
-            if (json && json.code && json.code === 6002) { // 6002 is the code for bad login
-                overlayStore.toast("Invalid username or password");
-            } else {
-                overlayStore.toast("Couldn't log in");
-            }
             buttonsEnabled = true;
-            return;
         }
     };
     const createAccountInstead = () => {
@@ -47,6 +43,9 @@
     <span class="h4" slot="header">Welcome back!</span>
 
     <svelte:fragment slot="content">
+        <RpcErrorDisplay response={response} />
+
+        <RpcErrorDisplay validationIndex={0} response={response} />
         <label class="input-label">
             Username
             <input class="input full-width" minlength="1" maxlength="32" bind:value={ username } />
@@ -54,6 +53,7 @@
 
         <div class="separator" />
 
+        <RpcErrorDisplay validationIndex={1} response={response} />
         <label class="input-label">
             Password
             <input class="input full-width" minlength="8" type="password" bind:value={ password } />
@@ -61,7 +61,7 @@
     </svelte:fragment>
 
     <svelte:fragment slot="footer">
-        <button class="button modal-secondary-action" on:click="{ createAccountInstead }">Create an account instead</button>
+        <button class="button modal-secondary-action" on:click="{ createAccountInstead }" disabled="{ !buttonsEnabled }">Create an account instead</button>
         <button class="button button-accent modal-primary-action" on:click="{ login }" disabled="{ !buttonsEnabled }">Log In</button>
     </svelte:fragment>
 </Modal>
diff --git a/frontend/src/components/rpc/RpcErrorDisplay.svelte b/frontend/src/components/rpc/RpcErrorDisplay.svelte
new file mode 100644
index 0000000..e800855
--- /dev/null
+++ b/frontend/src/components/rpc/RpcErrorDisplay.svelte
@@ -0,0 +1,41 @@
+<script>
+    import { getErrorFromResponse } from "../../request";
+
+    export let response = null;
+    export let validationIndex = -1;
+
+    let message = null;
+
+    $: {
+        const error = getErrorFromResponse(response);
+        if (error) {
+            if (validationIndex >= 0) {
+                if (error.validationErrors) {
+                    const found = error.validationErrors.find(e => e.index === validationIndex);
+                    if (found) {
+                        message = found.msg;
+                    }
+                } else {
+                    message = null;
+                }
+            } else {
+                if (error.validationErrors) {
+                    message = null;
+                } else {
+                    message = error.message;
+                }
+            }
+        }
+    }
+</script>
+
+<style>
+    span {
+        color: var(--red-1);
+        display: block;
+    }
+</style>
+
+{#if message}
+    <span>{ message }</span>
+{/if}
diff --git a/frontend/src/request.js b/frontend/src/request.js
index bb53087..e554f2c 100644
--- a/frontend/src/request.js
+++ b/frontend/src/request.js
@@ -29,34 +29,71 @@ export const methods = {
     getCommunityChannels: withCacheable(method(405, true)),
 };
 
-export function compatibleFetch(endpoint, options) {
-    if (window.fetch && typeof window.fetch === "function") {
-        return fetch(endpoint, options);
-    } else {
-        return new Promise((resolve, reject) => {
-            const req = new XMLHttpRequest();
-            req.addEventListener("load", () => {
-                resolve({
-                    status: req.status,
-                    ok: [200, 201, 204].includes(req.status),
-                    json() {
-                        return JSON.parse(req.responseText);
-                    }
-                });
-            });
-            req.addEventListener("error", (e) => {
-                reject(e);
-            });
-    
-            req.open(options.method || "GET", endpoint);
-            if (options.headers) {
-                for (const [header, value] of Object.entries(options.headers)) {
-                    req.setRequestHeader(header, value);
-                }
-            }
-            req.send(options.body);
-        });
+export const RPCError = {
+    BAD_REQUEST: { code: 6000, message: "Bad request" },
+    RPC_VALIDATION_ERROR: { code: 6001, message: "We couldn't validate this request" },
+    BAD_LOGIN_CREDENTIALS: { code: 6002, message: "Incorrect login credentials" },
+    BAD_AUTH: { code: 6003, message: "You're not authenticated" },
+    NOT_FOUND: { code: 6004, message: "Not found" },
+    FORBIDDEN_DUE_TO_MISSING_PERMISSIONS: { code: 6005, message: "You don't have the required permissions to perform this action" },
+    BAD_REQUEST_KEY: { code: 6006, message: "This request requires a special password, however, the password you provided was incorrect" },
+    GOT_NO_DATABASE_DATA: { code: 7001, message: "Sorry, we couldn't process this request (server expected data from database, however got none)" },
+    FEATURE_DISABLED: { code: 7002, message: "This feature is disabled" },
+    INTERNAL_ERROR: { code: 7003, message: "Sorry, we couldn't process this request (internal server error)" },
+};
+
+export const RequestStatus = {
+    OK: 0,
+    NETWORK_EXCEPTION: 1,
+    JSON_EXCEPTION: 2,
+    FAILURE_STATUS: 3,
+    RPC_ERROR: 4,
+    INVARIANT_RPC_RESPONSE_COUNT: 5,
+};
+
+export const RequestStatusToMessage = {
+    [RequestStatus.OK]: "",
+    [RequestStatus.NETWORK_EXCEPTION]: "We couldn't reach the server right now",
+    [RequestStatus.JSON_EXCEPTION]: "We couldn't process this request right now (server gave an invalid response, failed to parse as JSON)",
+    [RequestStatus.FAILURE_STATUS]: "We couldn't process this request right now (server gave a failure status code)",
+    [RequestStatus.RPC_ERROR]: "We couldn't process this request right now (RPC error)",
+    [RequestStatus.INVARIANT_RPC_RESPONSE_COUNT]: "We couldn't process this request right now (invalid RPC response)",
+};
+
+
+export function getErrorFromResponse(response) {
+    if (!response) return;
+    if (response.status === RequestStatus.OK) return;
+    console.log(response);
+
+    let message = RequestStatusToMessage[response.status];
+    if (!message) message = "Something went wrong (unknown request error)";
+
+    if (response.status === RequestStatus.RPC_ERROR) {
+        let rpcErrorMessage = Object.values(RPCError).find(({ code }) => code === response.data.code);
+        if (rpcErrorMessage) {
+            rpcErrorMessage = rpcErrorMessage.message;
+        } else {
+            rpcErrorMessage = "Something went wrong (unknown RPC error)";
+        }
+
+        if (response.data.code === RPCError.RPC_VALIDATION_ERROR.code) {
+            return { message: rpcErrorMessage, validationErrors: response.data.errors };
+        }
+
+        return { message: rpcErrorMessage };
     }
+
+    return { message };
+}
+
+export function getMessageFromResponse(response) {
+    return getErrorFromResponse(response).message || "Something went wrong";
+}
+
+export function responseOk(response) {
+    if (response.status !== RequestStatus.OK) return false;
+    return true;
 }
 
 export default function doRequest(method, endpoint, auth=true, body=null) {
@@ -82,32 +119,46 @@ export default function doRequest(method, endpoint, auth=true, body=null) {
                 };
             }
         }
-    
+
+        let res;
         try {
-            const res = await compatibleFetch(endpoint, options);
-            const json = res.status === 204 ? {} : await res.json();
-    
+            res = await fetch(endpoint, options);
+        } catch(o_O) {
             return resolve({
-                json,
-                ok: res.ok,
-            });
-        } catch (e) {
-            return resolve({
-                json: null,
-                ok: false,
+                status: RequestStatus.NETWORK_EXCEPTION
             });
         }
+
+        let json;
+        try {
+            json = res.status === 204 ? {} : await res.json();
+        } catch(o_O) {
+            return resolve({
+                status: RequestStatus.JSON_EXCEPTION
+            });
+        }
+
+        resolve({
+            data: json,
+            status: res.ok ? RequestStatus.OK : RequestStatus.FAILURE_STATUS
+        });
     });
 }
 
 export async function remoteCall({methodId, requiresAuthentication, cacheable, _isSignal=false}, ...args) {
     const calls = [[methodId, ...args]];
+
     if (requiresAuthentication && gateway.authenticated && !cacheable) {
         const replies = await gateway.sendRPCRequest(calls, _isSignal);
-        const ok = Array.isArray(replies) && !(replies[0] && replies[0].code);
+        if (!Array.isArray(replies) || replies.length !== 1) {
+            return { status: RequestStatus.INVARIANT_RPC_RESPONSE_COUNT };
+        }
+
+        const reply = replies[0];
+
         return {
-            json: ok ? replies[0] : null,
-            ok
+            data: reply,
+            status: reply && reply.code ? RequestStatus.RPC_ERROR : RequestStatus.OK
         };
     }
 
@@ -117,9 +168,21 @@ export async function remoteCall({methodId, requiresAuthentication, cacheable, _
     } else {
         response = await doRequest("POST", apiRoute("rpc"), requiresAuthentication, calls);
     }
-    response.ok = response.ok && Array.isArray(response.json) && !(response.json[0] && response.json[0].code);
-    response.json = response.ok ? response.json[0] : null;
-    return response;
+
+    if (response.status !== RequestStatus.OK) {
+        return { status: response.status };
+    }
+
+    if (!Array.isArray(response.data) || response.data.length !== 1) {
+        return { status: RequestStatus.INVARIANT_RPC_RESPONSE_COUNT };
+    }
+
+    const reply = response.data[0];
+
+    return {
+        data: reply,
+        status: reply && reply.code ? RequestStatus.RPC_ERROR : RequestStatus.OK
+    };
 }
 
 export async function remoteSignal(method, ...args) {
@@ -131,14 +194,22 @@ export async function remoteSignal(method, ...args) {
 
 export async function remoteBlobUpload({methodId, requiresAuthentication, _isSignal=false}, blob) {
     const calls = [[methodId, [0, blob.size]]];
+
     if (requiresAuthentication && gateway.authenticated) {
         const replies = await gateway.sendRPCRequest(calls, _isSignal, blob);
-        const ok = Array.isArray(replies) && !(replies[0] && replies[0].code);
+        if (!Array.isArray(replies) || replies.length !== 1) {
+            return { status: RequestStatus.INVARIANT_RPC_RESPONSE_COUNT };
+        }
+
+        const reply = replies[0];
+
         return {
-            json: ok ? replies[0] : null,
-            ok
+            data: reply,
+            status: reply && reply.code ? RequestStatus.RPC_ERROR : RequestStatus.OK
         };
     } else {
-        return { json: null, ok: false };
+        return  {
+            status: RequestStatus.NETWORK_EXCEPTION
+        };
     }
 }
diff --git a/frontend/src/stores.js b/frontend/src/stores.js
index 389949d..18c279f 100644
--- a/frontend/src/stores.js
+++ b/frontend/src/stores.js
@@ -1,6 +1,6 @@
 import gateway, { GatewayEventType, GatewayPayloadType, GatewayPresenceStatus } from "./gateway";
 import logger from "./logging";
-import { methods, remoteCall, remoteSignal } from "./request";
+import { getMessageFromResponse, methods, remoteCall, remoteSignal, responseOk } from "./request";
 import { getItem, setItem } from "./storage";
 
 const storeLog = logger("Store");
@@ -335,17 +335,17 @@ class MessageStore extends Store {
 
         const oldestMessage = this.value[0];
         const res = await remoteCall(methods.getChannelMessages, this.channelId, null, oldestMessage ? oldestMessage.id : null);
-        if (res.ok) {
-            if (res.json.length < 1)
+        if (responseOk(res)) {
+            if (res.data.length < 1)
                 return;
             if (beforeCommitToStore)
-                beforeCommitToStore(res.json);
-            res.json.reverse();
-            this.value = res.json.concat(this.value);
+                beforeCommitToStore(res.data);
+            res.data.reverse();
+            this.value = res.data.concat(this.value);
             this._recomputeMessages();
             this.updated();
         } else {
-            overlayStore.toast("Messages failed to load");
+            overlayStore.toast(`Messages failed to load: ${getMessageFromResponse(res)}`);
         }
     }
 
@@ -877,11 +877,11 @@ export const sendMessageAction = createAction("sendMessageAction", async ({chann
 
     const res = await remoteSignal(methods.createChannelMessage, channelId, content, optimisticMessageId, null);
 
-    if (!res.ok) {
+    if (!responseOk(res)) {
         messagesStoreForChannel.deleteMessage({
             id: optimisticMessageId
         });
-        overlayStore.toast("Couldn't send message");
+        overlayStore.toast(`Couldn't send message: ${getMessageFromResponse(res)}`);
     }
 });