From 4d77c6cf8a08cd29a38736e033e6c412c9e610dc Mon Sep 17 00:00:00 2001
From: Marcel Hellkamp <marc@gsites.de>
Date: Thu, 6 Jun 2024 11:13:41 +0200
Subject: [PATCH] Better error handling and visual clue on errors

---
 src/App.vue    | 68 ++++++++++++++++++++++++++++++++++---------
 src/main.ts    |  4 +--
 src/sources.ts | 78 +++++++++++++++++++++++++++++++++-----------------
 3 files changed, 109 insertions(+), 41 deletions(-)

diff --git a/src/App.vue b/src/App.vue
index cc0e0c2..fde9898 100644
--- a/src/App.vue
+++ b/src/App.vue
@@ -10,6 +10,7 @@ import { fetchPosts } from '@/sources'
 import Card from './components/Card.vue';
 import ConfigModal from './components/ConfigModal.vue';
 import InfoBar from './components/InfoBar.vue';
+import { arrayUnique } from './utils';
 
 const config = ref<Config>();
 
@@ -18,6 +19,9 @@ const pinned = ref<Array<string>>([])
 const hidden = ref<Array<string>>([])
 const updateInProgress = ref(false)
 
+const statusText = ref<string | undefined>("Initializing ...")
+const statusIsError = ref(false)
+
 var updateIntervalHandle: number;
 var lastUpdate = 0;
 
@@ -127,10 +131,19 @@ async function updateWall() {
   updateInProgress.value = true
 
   try {
-    allPosts.value = await fetchPosts(cfg)
+    allPosts.value = await fetchPosts(cfg, progress => {
+      if (progress.errors.length) {
+        setStatus(progress.errors.slice(-1)[0].message, true)
+      } else if (progress.finished < progress.total) {
+        setStatus(`Updating [${progress.finished}/${progress.total}] ...`)
+      } else {
+        setStatus(false)
+      }
+    })
+
     console.debug("Update completed")
   } catch (e) {
-    console.warn("Update failed", e)
+    setStatus(`Update failed: ${e}`)
   } finally {
     lastUpdate = Date.now()
     updateInProgress.value = false;
@@ -138,18 +151,29 @@ async function updateWall() {
 
 }
 
+
+function setStatus(text: string | false, isError?: boolean) {
+  if (text === false) {
+    statusText.value = undefined
+    statusIsError.value = false
+  } else {
+    statusText.value = text
+    statusIsError.value = isError === true
+  }
+}
+
 /**
  * Filter and order posts based on real-time criteria (e.g. pinned or hidden posts).
  * Most of filtering already happened earlier.
  */
 const filteredPosts = computed(() => {
   // Copy to make sure those are detected as a reactive dependencies
-  var posts: Array<Post> = [... allPosts.value]
+  var posts: Array<Post> = [...allPosts.value]
   const pinnedLocal = [...pinned.value]
   const hiddenLocal = [...hidden.value]
 
   // Filter hidden posts, authors or domains
-  posts = posts.filter((p) => !hiddenLocal.some(hide => 
+  posts = posts.filter((p) => !hiddenLocal.some(hide =>
     p.id == hide || p.author?.profile.endsWith(hide)
   ))
 
@@ -186,7 +210,8 @@ const hideAuthor = (profile: string) => {
 
 const hideDomain = (profile: string) => {
   var domain = profile.split("@").pop()
-  toggle(hidden.value, "@" + domain)
+  if (domain)
+    toggle(hidden.value, "@" + domain)
 }
 
 const toggleTheme = () => {
@@ -204,8 +229,7 @@ const privacyLink = computed(() => {
 
 <template>
   <div id="page">
-    <icon v-show="updateInProgress" icon="spinner" spin
-      class="position-fixed bottom-0 start-0 m-1 opacity-25 text-muted" />
+
     <header v-if="config?.showInfobar" class="secret-hover" style="cursor: context-menu" data-bs-toggle="modal"
       data-bs-target="#configModal" title="Click to edit wall settings">
       <span class="text-muted float-end secret">
@@ -214,11 +238,16 @@ const privacyLink = computed(() => {
       <InfoBar :config="config" />
     </header>
 
+    <aside id="status-row" class="position-absolute opacity-25">
+      <Transition>
+        <icon v-if="statusIsError" icon="triangle-exclamation" class="mx-1" :title="statusText" />
+        <icon v-else-if="updateInProgress" icon="spinner" spin class="mx-1" />
+      </Transition>
+    </aside>
+
     <main>
-      <div v-if="config === undefined">Initializing ...</div>
-      <div v-else-if="filteredPosts.length === 0 && updateInProgress">Loading first posts ...</div>
-      <div v-else-if="filteredPosts.length === 0">Nothing there yet ...</div>
-      <div v-else v-masonry transition-duration="1s" item-selector=".wall-item" percent-position="true" id="wall">
+      <div v-if="config && filteredPosts.length > 0" v-masonry transition-duration="1s" item-selector=".wall-item"
+        percent-position="true" id="wall">
         <Card v-masonry-tile class="wall-item secret-hover" v-for="post in filteredPosts" :key="post.id" :post="post"
           :config="config">
 
@@ -228,7 +257,7 @@ const privacyLink = computed(() => {
                 aria-expanded="false">...</button>
               <ul class="dropdown-menu">
                 <li><a class="dropdown-item" href="#" @click.prevent="pin(post.id)">{{ post.pinned ? "Unpin" : "Pin"
-                }}</a></li>
+                    }}</a></li>
                 <li><a class="dropdown-item" href="#" @click.prevent="hide(post.id)">Hide Post</a></li>
                 <li v-if="post.author?.profile"><a class="dropdown-item" href="#"
                     @click.prevent="hideAuthor(post.author?.profile)">Hide
@@ -247,8 +276,11 @@ const privacyLink = computed(() => {
     <ConfigModal v-if="config" v-model="config" id="configModal" />
 
     <footer>
+      <aside class="opacity-50 text-center">
+        Status: {{ statusText || "OK" }}
+      </aside>
       <button class="btn btn-link text-muted" @click="toggleTheme(); false">[{{ actualTheme == "dark" ? "Light" : "Dark"
-      }} mode]</button>
+        }} mode]</button>
       <button class="btn btn-link text-muted" data-bs-toggle="modal" data-bs-target="#configModal">[Customize]</button>
       <div>
         <a href="https://github.com/defnull/fediwall" target="_blank" class="mx-1 text-muted">Fediwall <span
@@ -363,4 +395,14 @@ body {
     width: 100%;
   }
 }
+
+.v-enter-active,
+.v-leave-active {
+  transition: opacity 0.3s ease;
+}
+
+.v-enter-from,
+.v-leave-to {
+  opacity: 0;
+}
 </style>
diff --git a/src/main.ts b/src/main.ts
index 6c884a8..e4c0621 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -27,8 +27,8 @@ import VueDOMPurifyHTML from 'vue-dompurify-html';
 // Register fontawesome icons
 import { library } from '@fortawesome/fontawesome-svg-core'
 import { FontAwesomeIcon } from '@fortawesome/vue-fontawesome'
-import { faGear, faSpinner } from '@fortawesome/free-solid-svg-icons'
-library.add(faGear, faSpinner)
+import { faGear, faSpinner, faTriangleExclamation } from '@fortawesome/free-solid-svg-icons'
+library.add(faGear, faSpinner, faTriangleExclamation)
 
 import App from '@/App.vue'
 const app = createApp(App)
diff --git a/src/sources.ts b/src/sources.ts
index abca2ff..1d9e5d8 100644
--- a/src/sources.ts
+++ b/src/sources.ts
@@ -5,22 +5,32 @@ import type { faTags } from "@fortawesome/free-solid-svg-icons";
 import DOMPurify from 'dompurify'
 
 /**
- * Fetch unique posts from all sources (curently only Mastodon is implemented)
+ * Fetch unique posts from all sources (currently only Mastodon is implemented)
  */
-export async function fetchPosts(cfg: Config): Promise<Post[]> {
+export type Progress = {
+    total: number
+    started: number
+    finished: number
+    errors: Error[]
+}
+
+export async function fetchPosts(cfg: Config, onProgress: (progress: Progress) => void): Promise<Post[]> {
+
     type Task = () => Promise<MastodonStatus[]>;
+    let progress: Progress = {total: 0, started: 0, finished: 0, errors: []}
 
     // Group tasks by domain (see below)
     const domainTasks: Record<string, Array<Task>> = {}
     const addTask = (domain: string, task: Task) => {
+        progress.total += 1;
         (domainTasks[domain] ??= []).push(task)
     }
 
     // Load tags from all servers
     for (const domain of cfg.servers) {
         const query: Record<string, any> = { limit: cfg.limit }
-        if(cfg.badWords.length) query.none = cfg.badWords.join(",")
-        if(!cfg.showText) query.only_media = "True"
+        if (cfg.badWords.length) query.none = cfg.badWords.join(",")
+        if (!cfg.showText) query.only_media = "True"
         for (const tag of cfg.tags) {
             addTask(domain, async () => {
                 return await fetchJson(domain, `api/v1/timelines/tag/${encodeURIComponent(tag)}`, query)
@@ -93,14 +103,19 @@ export async function fetchPosts(cfg: Config): Promise<Post[]> {
         .map(([domain, tasks]) => {
             return async () => {
                 for (const task of tasks) {
+                    progress.started += 1;
                     try {
                         (await task())
                             .map(status => fixLocalAcct(domain, status))
                             .filter(status => filterStatus(cfg, status))
                             .map(status => statusToWallPost(cfg, status))
                             .forEach(addOrRepacePost)
-                    } catch (err) {
-                        console.warn(`Update task failed for domain ${domain}`, err)
+                    } catch (err: any) {
+                        let error = err instanceof Error ? err : new Error(err?.toString())
+                        progress.errors.push(error)
+                    } finally {
+                        progress.finished += 1
+                        onProgress(progress)
                     }
                 }
             }
@@ -145,34 +160,45 @@ async function fetchJson(domain: string, path: string, query?: Record<string, an
         const pairs = Object.entries(query).map(([key, value]) => [key, value.toString()])
         url += "?" + new URLSearchParams(pairs).toString()
     }
-    let rs = await fetch(url)
 
-    // Auto-retry rate limit errors
-    let errCount = 0
-    while (!rs.ok) {
-        if (errCount++ > 3)
-            break // Do not retry anymore
+    let rs: Response;
+    let json: any;
 
-        if (rs.headers.get("X-RateLimit-Remaining") === "0") {
-            const resetTime = new Date(rs.headers.get("X-RateLimit-Reset") || (new Date().getTime() + 10000)).getTime();
-            const referenceTime = new Date(rs.headers.get("Date") || new Date()).getTime();
-            const sleep = Math.max(0, resetTime - referenceTime) + 1000 // 1 second leeway
-            await new Promise(resolve => setTimeout(resolve, sleep));
-        } else {
-            break // Do not retry
-        }
+    await new Promise(resolve => setTimeout(resolve, 1000));
 
-        // Retry
+    try {
         rs = await fetch(url)
+
+        // Auto-retry rate limit errors
+        let errCount = 0
+        while (!rs.ok) {
+            if (errCount++ > 3)
+                break // Do not retry anymore
+
+            if (rs.headers.get("X-RateLimit-Remaining") === "0") {
+                const resetTime = new Date(rs.headers.get("X-RateLimit-Reset") || (new Date().getTime() + 10000)).getTime();
+                const referenceTime = new Date(rs.headers.get("Date") || new Date()).getTime();
+                const sleep = Math.max(0, resetTime - referenceTime) + 1000 // 1 second leeway
+                await new Promise(resolve => setTimeout(resolve, sleep));
+            } else {
+                break // Do not retry
+            }
+
+            // Retry
+            rs = await fetch(url)
+        }
+        json = await rs.json()
+    } catch (e: any) {
+        throw new Error(`Failed to fetch ${url} (${e.message || e})`);
     }
 
-    const json = await rs.json()
-    if (json.error) {
-        console.warn(`Fetch error: ${rs.status} ${JSON.stringify(json)}`)
-        const err = new Error(json.error);
+    if (!rs.ok || json.error) {
+        const err = new Error(`Failed to fetch ${url} (${rs.status}: ${json.error || "Unknown reason"})`);
         (err as any).status = rs.status;
+        (err as any).body = json;
         throw err;
     }
+
     return json
 }
 
@@ -218,7 +244,7 @@ const filterStatus = (cfg: Config, status: MastodonStatus) => {
 }
 
 /**
- * Convert a mastdon status object to a Post.
+ * Convert a mastodon status object to a Post.
  */
 const statusToWallPost = (cfg: Config, status: MastodonStatus): Post => {
     const date = new Date(status.created_at)