Preserve the guide until a complete EPG refresh can activate

Adapted from MikaelKW/nodecast-tv-plus commits c267d98d734753a09b08d267c8ec2c3fa11c33f5, b761690bac7626a3cc5ddf754d96b14a02f506fe, and 5524fdaffed5c6a44ae69474e7eaa2f18d428c75. Preserve every parser batch, decode gzip once, and retain live channel metadata.

Co-authored-by: Mikael <mikaelkwessel@gmail.com>

server/routes/sources.js

@@ -120,6 +120,7 @@ router.delete('/:id', async (req, res) => {
         }
 
         // Cascade delete: Clean up SQLite data for this source
+        syncService.invalidateEpgSource(sourceId);
         const db = getDb();
         const deleteCategories = db.prepare('DELETE FROM categories WHERE source_id = ?');
         const deleteItems = db.prepare('DELETE FROM playlist_items WHERE source_id = ?');

server/services/epgParser.js

@@ -1,448 +1,179 @@
-/**
+/** Streaming XMLTV parsing with bounded batches and complete-document validation. */
- * EPG (XMLTV) Parser (Streaming)
- * Parses XMLTV format EPG data and extracts channel/programme information using streaming XML parser
- */
-
 const sax = require('sax');
-const zlib = require('zlib');
+const zlib = require('node:zlib');
-const { Readable } = require('stream');
+const { Readable } = require('node:stream');
+const { pipeline } = require('node:stream/promises');
+const { StringDecoder } = require('node:string_decoder');
+const { parseXmltvDate } = require('./xmltvDate');
 
-/**
+async function* parseStreaming(input, batchSize = 1000) {
- * Parse XMLTV date format (YYYYMMDDHHmmss +ZZZZ)
+    if (!Number.isInteger(batchSize) || batchSize < 1) throw new Error('Invalid EPG batch size');
- * @param {string} dateStr - XMLTV format date string
+    const stream = typeof input === 'string' ? Readable.from([input]) : input;
- * @returns {Date}
+    const parser = sax.parser(true, { trim: true, normalize: true });
- */
+    const decoder = new StringDecoder('utf8');
-function parseXmltvDate(dateStr) {
+    let channels = [], programmes = [], skippedProgrammes = 0;
-    if (!dateStr) return null;
+    const ready = [];
+    let currentObject = null, objectTag = null, textBuffer = '';
+    let validTimestamps = true, error = null, depth = 0;
+    let sawTvRoot = false, closedTvRoot = false;
 
-    // Format: 20231225120000 +0000
+    const queueBatch = isLast => {
-    const match = dateStr.match(/^(\d{4})(\d{2})(\d{2})(\d{2})(\d{2})(\d{2})\s*([+-]\d{4})?$/);
+        ready.push({ channels, programmes, skippedProgrammes, isLast });
-    if (!match) {
+        channels = [];
-        // Try ISO format fallback
+        programmes = [];
-        return new Date(dateStr);
+        skippedProgrammes = 0;
-    }
+    };
-
+    parser.onerror = e => {
-    const [, year, month, day, hour, minute, second, tz] = match;
+        error ||= new Error(`Invalid XMLTV document: ${e.message}`);
-    let isoStr = `${year}-${month}-${day}T${hour}:${minute}:${second}`;
+        parser.resume();
-
+    };
-    if (tz) {
+    parser.onopentag = node => {
-        const tzHours = tz.substring(0, 3);
+        if (depth === 0) {
-        const tzMins = tz.substring(3);
+            if (node.name !== 'tv' || sawTvRoot) error ||= new Error('Invalid XMLTV document: expected one <tv> root');
-        isoStr += `${tzHours}:${tzMins}`;
+            sawTvRoot = node.name === 'tv';
-    } else {
-        isoStr += 'Z';
-    }
-
-    return new Date(isoStr);
-}
-
-/**
- * Parse XMLTV content (Stream or String)
- * @param {Readable|string} input - XMLTV content as Stream or String
- * @returns {Promise<{ channels: Array, programmes: Array }>}
- */
-function parse(input) {
-    return new Promise((resolve, reject) => {
-        const channels = [];
-        const programmes = [];
-
-        const saxStream = sax.createStream(true, { trim: true, normalize: true }); // strict mode
-
-        let currentTag = null;
-        let currentObject = null;
-        let textBuffer = '';
-
-        saxStream.on('error', function (e) {
-            // clear the error
-            this._parser.error = null;
-            this._parser.resume();
-            console.warn('XML Parse Warning:', e.message);
-        });
-
-        saxStream.on('opentag', function (node) {
-            currentTag = node.name;
-            const attr = node.attributes;
-
-            if (currentTag === 'channel') {
-                currentObject = {
-                    id: attr.id,
-                    name: null, // Will be populated by display-name tag
-                    icon: null,
-                    url: null
-                };
-            } else if (currentTag === 'programme') {
-                currentObject = {
-                    channelId: attr.channel,
-                    start: parseXmltvDate(attr.start),
-                    stop: parseXmltvDate(attr.stop),
-                    title: null,
-                    subtitle: null,
-                    description: null,
-                    category: [],
-                    icon: null,
-                    date: null,
-                    episodeNum: null
-                };
-            } else if (currentTag === 'icon') {
-                if (currentObject) {
-                    currentObject.icon = attr.src;
-                }
-            }
-            textBuffer = '';
-        });
-
-        saxStream.on('text', function (text) {
-            textBuffer += text;
-        });
-
-        saxStream.on('cdata', function (text) {
-            textBuffer += text;
-        });
-
-        saxStream.on('closetag', function (tagName) {
-            if (tagName === 'channel') {
-                if (currentObject) channels.push(currentObject);
-                currentObject = null;
-            } else if (tagName === 'programme') {
-                if (currentObject) programmes.push(currentObject);
-                currentObject = null;
-            } else if (currentObject) {
-                // Handle properties within objects
-                switch (tagName) {
-                    case 'display-name': // channel name
-                        if (!currentObject.name) currentObject.name = textBuffer;
-                        break;
-                    case 'url': // channel url
-                        currentObject.url = textBuffer;
-                        break;
-                    case 'title':
-                        currentObject.title = textBuffer;
-                        break;
-                    case 'sub-title':
-                        currentObject.subtitle = textBuffer;
-                        break;
-                    case 'desc':
-                        currentObject.description = textBuffer;
-                        break;
-                    case 'category':
-                        if (textBuffer && currentObject.category) currentObject.category.push(textBuffer);
-                        break;
-                    case 'date':
-                        currentObject.date = textBuffer;
-                        break;
-                    case 'episode-num':
-                        // Prefer system "xmltv_ns" or just take text
-                        // Complex episode parsing logic can go here if needed
-                        currentObject.episodeNum = textBuffer;
-                        break;
-                }
-            }
-        });
-
-        saxStream.on('end', function () {
-            resolve({ channels, programmes });
-        });
-
-        // Handle input type
-        if (typeof input === 'string') {
-            const inputStream = Readable.from([input]);
-            inputStream.pipe(saxStream);
-        } else {
-            input.pipe(saxStream);
         }
-    });
+        depth++;
+        const attr = node.attributes;
+        if (depth === 2 && node.name === 'channel') {
+            objectTag = 'channel';
+            currentObject = { id: attr.id, name: null, icon: null, url: null };
+        } else if (depth === 2 && node.name === 'programme') {
+            objectTag = 'programme';
+            const start = parseXmltvDate(attr.start), stop = parseXmltvDate(attr.stop);
+            validTimestamps = Boolean(attr.channel && start) && (!attr.stop || Boolean(stop));
+            currentObject = { channelId: attr.channel, start, stop, title: null,
+                subtitle: null, description: null, category: [], icon: null, date: null, episodeNum: null };
+        } else if (node.name === 'icon' && currentObject) {
+            currentObject.icon = attr.src;
+        }
+        textBuffer = '';
+    };
+    parser.ontext = text => { textBuffer += text; };
+    parser.oncdata = parser.ontext;
+    parser.onclosetag = tag => {
+        if (depth === 1 && tag === 'tv') closedTvRoot = true;
+        if (depth === 2 && tag === objectTag) {
+            if (objectTag === 'channel' && currentObject.id) {
+                currentObject.name ||= currentObject.id;
+                channels.push(currentObject);
+            } else if (objectTag === 'programme') {
+                if (validTimestamps) programmes.push(currentObject);
+                else skippedProgrammes++;
+            }
+            currentObject = null;
+            objectTag = null;
+            if (programmes.length >= batchSize || channels.length >= batchSize) queueBatch(false);
+        } else if (currentObject) {
+            switch (tag) {
+                case 'display-name': currentObject.name ||= textBuffer; break;
+                case 'url': currentObject.url = textBuffer; break;
+                case 'title': currentObject.title = textBuffer; break;
+                case 'sub-title': currentObject.subtitle = textBuffer; break;
+                case 'desc': currentObject.description = textBuffer; break;
+                case 'category': if (textBuffer && currentObject.category) currentObject.category.push(textBuffer); break;
+                case 'date': currentObject.date = textBuffer; break;
+                case 'episode-num': currentObject.episodeNum = textBuffer; break;
+            }
+        }
+        depth--;
+    };
+
+    try {
+        for await (const chunk of stream) {
+            const bytes = typeof chunk === 'string' ? Buffer.from(chunk) : chunk;
+            // A network chunk can contain many batches. Keep each one and yield
+            // between bounded SAX writes instead of overwriting a pending batch.
+            for (let offset = 0; offset < bytes.length; offset += 16384) {
+                parser.write(decoder.write(bytes.subarray(offset, offset + 16384)));
+                if (error) throw error;
+                while (ready.length) yield ready.shift();
+            }
+        }
+        parser.write(decoder.end()).close();
+        if (error) throw error;
+        if (!sawTvRoot || !closedTvRoot) throw new Error('Invalid XMLTV document: missing complete <tv> root');
+        queueBatch(true);
+        while (ready.length) yield ready.shift();
+    } finally {
+        stream.destroy?.();
+    }
+}
+
+async function parse(input) {
+    const channels = [], programmes = [];
+    let skippedProgrammes = 0;
+    for await (const batch of parseStreaming(input)) {
+        channels.push(...batch.channels);
+        programmes.push(...batch.programmes);
+        skippedProgrammes += batch.skippedProgrammes;
+    }
+    return { channels, programmes, skippedProgrammes };
+}
+
+async function* fetchAndParseStreaming(url, batchSize = 1000) {
+    const response = await fetch(url);
+    if (!response.ok) {
+        await response.body?.cancel();
+        throw new Error(`Failed to fetch EPG: ${response.status} ${response.statusText}`);
+    }
+    const body = response.body && typeof response.body.pipe === 'function'
+        ? response.body : response.body ? Readable.fromWeb(response.body) : Readable.from([]);
+    let source, decoded, completion;
+    try {
+        // Fetch transparently decodes Content-Encoding. Inspect actual bytes
+        // so .gz downloads work without double-decompressing HTTP gzip.
+        const iterator = body[Symbol.asyncIterator]();
+        const prefix = [];
+        let prefixLength = 0;
+        while (prefixLength < 2) {
+            const next = await iterator.next();
+            if (next.done) break;
+            const chunk = Buffer.from(next.value);
+            prefix.push(chunk);
+            prefixLength += chunk.length;
+        }
+        const first = Buffer.concat(prefix);
+        source = Readable.from((async function* () {
+            if (first.length) yield first;
+            for await (const chunk of { [Symbol.asyncIterator]: () => iterator }) yield chunk;
+        })(), { objectMode: false });
+        decoded = source;
+        if (first[0] === 0x1f && first[1] === 0x8b) {
+            decoded = zlib.createGunzip();
+            completion = pipeline(source, decoded);
+            completion.catch(() => {}); // The decoder's async iterator reports failures.
+        }
+        yield* parseStreaming(decoded, batchSize);
+    } finally {
+        decoded?.destroy();
+        source?.destroy();
+        body.destroy();
+        if (completion) await completion.catch(() => {});
+    }
+}
+
+async function fetchAndParse(url) {
+    const channels = [], programmes = [];
+    let skippedProgrammes = 0;
+    for await (const batch of fetchAndParseStreaming(url)) {
+        channels.push(...batch.channels);
+        programmes.push(...batch.programmes);
+        skippedProgrammes += batch.skippedProgrammes;
+    }
+    return { channels, programmes, skippedProgrammes };
 }
 
-/**
- * Get programmes for a specific channel
- */
 function getProgrammesForChannel(programmes, channelId) {
     return programmes.filter(p => p.channelId === channelId);
 }
 
-/**
- * Get current and upcoming programmes for a channel
- */
 function getCurrentAndUpcoming(programmes, channelId, count = 5) {
     const now = new Date();
     const channelProgrammes = getProgrammesForChannel(programmes, channelId);
-
-    // Sort by start time
     channelProgrammes.sort((a, b) => a.start - b.start);
-
+    return { current: channelProgrammes.find(p => p.start <= now && p.stop > now),
-    // Find current and upcoming
+        upcoming: channelProgrammes.filter(p => p.start > now).slice(0, count) };
-    const current = channelProgrammes.find(p => p.start <= now && p.stop > now);
-    const upcoming = channelProgrammes
-        .filter(p => p.start > now)
-        .slice(0, count);
-
-    return { current, upcoming };
 }
 
-/**
+module.exports = { parse, parseXmltvDate, fetchAndParse, fetchAndParseStreaming,
- * Fetch and parse XMLTV from URL
+    parseStreaming, getProgrammesForChannel, getCurrentAndUpcoming };
- */
-async function fetchAndParse(url) {
-    const response = await fetch(url);
-    if (!response.ok) {
-        throw new Error(`Failed to fetch EPG: ${response.status} ${response.statusText}`);
-    }
-
-    let stream;
-    if (response.body && typeof response.body.pipe === 'function') {
-        stream = response.body;
-    } else if (response.body) {
-        stream = Readable.fromWeb(response.body);
-    } else {
-        stream = Readable.from([]);
-    }
-
-    // Check for GZIP
-    // Note: We can't easily check for magic bytes on a stream without buffering.
-    // We'll rely on response headers or file extension mostly, or try to peek.
-    // For now, let's assume if content-encoding is gzip OR url ends in .gz
-
-    // However, undici/fetch usually handles 'Content-Encoding: gzip' automatically transparently.
-    // We only need to manually gunzip if the server serves it as application/octet-stream but it's actually gzipped, 
-    // or if it's a .gz file download.
-
-    // A robust way for streams is checking magic bytes, but that requires peeking.
-    // Simplified approach: try to pipe through gunzip if the URL indicates it.
-
-    const isGzipped = url.endsWith('.gz') || (response.headers.get('content-type') || '').includes('gzip');
-
-    if (isGzipped) {
-        const gunzip = zlib.createGunzip();
-        stream.pipe(gunzip);
-        return parse(gunzip);
-    }
-
-    // In the previous version we read magic bytes. 
-    // To support that with streams we'd need a peek stream.
-    // For now let's trust the transparent decompression of fetch or the URL.
-
-    return parse(stream);
-}
-
-/**
- * Streaming EPG parser that yields batches of programmes (memory-efficient)
- * Channels are collected and returned with the first batch, then programmes are yielded in batches.
- * 
- * @param {string} url - XMLTV URL
- * @param {number} batchSize - Number of programmes per batch (default: 1000)
- * @yields {{ channels: Array|null, programmes: Array, isLast: boolean }}
- */
-async function* fetchAndParseStreaming(url, batchSize = 1000) {
-    const response = await fetch(url);
-    if (!response.ok) {
-        throw new Error(`Failed to fetch EPG: ${response.status} ${response.statusText}`);
-    }
-
-    let stream;
-    if (response.body && typeof response.body.pipe === 'function') {
-        stream = response.body;
-    } else if (response.body) {
-        stream = Readable.fromWeb(response.body);
-    } else {
-        stream = Readable.from([]);
-    }
-
-    const isGzipped = url.endsWith('.gz') || (response.headers.get('content-type') || '').includes('gzip');
-
-    if (isGzipped) {
-        const gunzip = zlib.createGunzip();
-        stream.pipe(gunzip);
-        stream = gunzip;
-    }
-
-    // Use async iterator pattern with SAX
-    yield* parseStreaming(stream, batchSize);
-}
-
-/**
- * Parse XMLTV as streaming async generator
- * @param {Readable} input - XMLTV stream
- * @param {number} batchSize - Number of programmes per batch
- * @yields {{ channels: Array|null, programmes: Array, isLast: boolean }}
- */
-async function* parseStreaming(input, batchSize = 1000) {
-    const channels = [];
-    let programmeBatch = [];
-    let channelsYielded = false;
-
-    // We need to convert SAX events to an async iterator
-    // This requires collecting events and yielding when batch is full
-
-    const saxStream = sax.createStream(true, { trim: true, normalize: true });
-
-    let currentTag = null;
-    let currentObject = null;
-    let textBuffer = '';
-    let resolveNext = null;
-    let pendingBatch = null;
-    let ended = false;
-    let error = null;
-
-    saxStream.on('error', function (e) {
-        this._parser.error = null;
-        this._parser.resume();
-        console.warn('XML Parse Warning:', e.message);
-    });
-
-    saxStream.on('opentag', function (node) {
-        currentTag = node.name;
-        const attr = node.attributes;
-
-        if (currentTag === 'channel') {
-            currentObject = {
-                id: attr.id,
-                name: null,
-                icon: null,
-                url: null
-            };
-        } else if (currentTag === 'programme') {
-            currentObject = {
-                channelId: attr.channel,
-                start: parseXmltvDate(attr.start),
-                stop: parseXmltvDate(attr.stop),
-                title: null,
-                subtitle: null,
-                description: null,
-                category: [],
-                icon: null,
-                date: null,
-                episodeNum: null
-            };
-        } else if (currentTag === 'icon') {
-            if (currentObject) {
-                currentObject.icon = attr.src;
-            }
-        }
-        textBuffer = '';
-    });
-
-    saxStream.on('text', function (text) {
-        textBuffer += text;
-    });
-
-    saxStream.on('cdata', function (text) {
-        textBuffer += text;
-    });
-
-    saxStream.on('closetag', function (tagName) {
-        if (tagName === 'channel') {
-            if (currentObject) channels.push(currentObject);
-            currentObject = null;
-        } else if (tagName === 'programme') {
-            if (currentObject) {
-                programmeBatch.push(currentObject);
-
-                // Check if we should yield a batch
-                if (programmeBatch.length >= batchSize) {
-                    const batch = {
-                        channels: !channelsYielded ? channels : null,
-                        programmes: programmeBatch,
-                        isLast: false
-                    };
-                    channelsYielded = true;
-                    programmeBatch = [];
-
-                    if (resolveNext) {
-                        resolveNext(batch);
-                        resolveNext = null;
-                    } else {
-                        pendingBatch = batch;
-                    }
-                }
-            }
-            currentObject = null;
-        } else if (currentObject) {
-            switch (tagName) {
-                case 'display-name':
-                    if (!currentObject.name) currentObject.name = textBuffer;
-                    break;
-                case 'url':
-                    currentObject.url = textBuffer;
-                    break;
-                case 'title':
-                    currentObject.title = textBuffer;
-                    break;
-                case 'sub-title':
-                    currentObject.subtitle = textBuffer;
-                    break;
-                case 'desc':
-                    currentObject.description = textBuffer;
-                    break;
-                case 'category':
-                    if (textBuffer && currentObject.category) currentObject.category.push(textBuffer);
-                    break;
-                case 'date':
-                    currentObject.date = textBuffer;
-                    break;
-                case 'episode-num':
-                    currentObject.episodeNum = textBuffer;
-                    break;
-            }
-        }
-    });
-
-    saxStream.on('end', function () {
-        ended = true;
-        // Yield final batch
-        const batch = {
-            channels: !channelsYielded ? channels : null,
-            programmes: programmeBatch,
-            isLast: true
-        };
-        if (resolveNext) {
-            resolveNext(batch);
-            resolveNext = null;
-        } else {
-            pendingBatch = batch;
-        }
-    });
-
-    saxStream.on('error', function (e) {
-        error = e;
-        if (resolveNext) {
-            resolveNext(null);
-        }
-    });
-
-    // Start piping
-    input.pipe(saxStream);
-
-    // Yield batches as they become available
-    while (!ended || pendingBatch) {
-        if (pendingBatch) {
-            const batch = pendingBatch;
-            pendingBatch = null;
-            yield batch;
-            if (batch.isLast) break;
-        } else if (!ended) {
-            // Wait for next batch
-            const batch = await new Promise(resolve => {
-                resolveNext = resolve;
-            });
-            if (batch) {
-                yield batch;
-                if (batch.isLast) break;
-            }
-        }
-    }
-
-    if (error) {
-        throw error;
-    }
-}
-
-module.exports = {
-    parse,
-    parseXmltvDate,
-    fetchAndParse,
-    fetchAndParseStreaming,
-    parseStreaming,
-    getProgrammesForChannel,
-    getCurrentAndUpcoming
-};
-

server/services/syncService.js

@@ -3,9 +3,12 @@ const { sources, settings } = require('../db'); // For source config and setting
 const xtreamApi = require('./xtreamApi');
 const m3uParser = require('./m3uParser');
 const epgParser = require('./epgParser');
+const { randomUUID } = require('node:crypto');
 
 // Sync tracking
 const activeSyncs = new Set(); // sourceId
+const activeEpgSyncs = new Set();
+const epgSourceGenerations = new Map();
 
 class SyncService {
     constructor() {
@@ -14,6 +17,11 @@ class SyncService {
         this._currentInterval = null;
     }
 
+    invalidateEpgSource(sourceId) {
+        const key = String(sourceId);
+        epgSourceGenerations.set(key, (epgSourceGenerations.get(key) || 0) + 1);
+    }
+
     /**
      * Get when the last global sync completed
      */
@@ -389,107 +397,216 @@ class SyncService {
      * Processes EPG files in batches to avoid OOM on large EPG data
      */
     async syncEpgFromUrl(sourceId, url) {
-        console.log(`[Sync] Fetching EPG from: ${url.substring(0, 60)}...`);
+        console.log(`[Sync] Fetching EPG from: ${new URL(url).origin}`);
 
-        // Temporary memory logging for verification
+        const sourceKey = String(sourceId);
-        const logMemory = () => {
+        if (activeEpgSyncs.has(sourceKey)) {
-            const used = process.memoryUsage();
+            throw new Error(`EPG refresh already in progress for source ${sourceId}`);
-            console.log(`[Sync] Memory: ${Math.round(used.heapUsed / 1024 / 1024)}MB heap`);
-        };
-
-        logMemory();
-
-        const db = getDb();
-        let allChannels = [];
-        let totalProgrammes = 0;
-        let batchCount = 0;
-
-        // Clear old programmes first
-        db.prepare('DELETE FROM epg_programs WHERE source_id = ?').run(sourceId);
-
-        const programmeStmt = db.prepare(`
-            INSERT INTO epg_programs (channel_id, source_id, start_time, end_time, title, description, data)
-            VALUES (?, ?, ?, ?, ?, ?, ?)
-        `);
-
-        const insertProgrammes = db.transaction((progs) => {
-            for (const p of progs) {
-                programmeStmt.run(
-                    p.channelId,
-                    sourceId,
-                    p.start ? p.start.getTime() : 0,
-                    p.stop ? p.stop.getTime() : 0,
-                    p.title,
-                    p.description || p.desc,
-                    JSON.stringify(p)
-                );
-            }
-        });
-
-        // Stream and process in batches (default 1000 programmes per batch)
-        for await (const batch of epgParser.fetchAndParseStreaming(url)) {
-            batchCount++;
-
-            // Collect channels from first batch
-            if (batch.channels) {
-                allChannels = batch.channels;
-            }
-
-            // Save this batch of programmes immediately
-            if (batch.programmes.length > 0) {
-                insertProgrammes(batch.programmes);
-                totalProgrammes += batch.programmes.length;
-            }
-
-            // Log progress every 10 batches
-            if (batchCount % 10 === 0) {
-                console.log(`[Sync] Processed ${totalProgrammes} programmes so far...`);
-                logMemory();
-            }
-
-            // Yield to event loop
-            await new Promise(resolve => setImmediate(resolve));
         }
+        activeEpgSyncs.add(sourceKey);
+        const sourceGeneration = epgSourceGenerations.get(sourceKey) || 0;
+        let cleanupRun = null;
+        let refreshError = null;
 
-        console.log(`[Sync] EPG Parsed: ${allChannels.length} channels, ${totalProgrammes} programmes`);
+        try {
-        logMemory();
 
-        // Save EPG Channels
+            // Temporary memory logging for verification
-        if (allChannels.length > 0) {
+            const logMemory = () => {
+                const used = process.memoryUsage();
+                console.log(`[Sync] Memory: ${Math.round(used.heapUsed / 1024 / 1024)}MB heap`);
+            };
+
+            logMemory();
+
+            const db = getDb();
+            const runId = randomUUID();
+            let totalChannels = 0;
+            let totalProgrammes = 0;
+            let skippedProgrammes = 0;
+            let batchCount = 0;
+            let sawFinalBatch = false;
+
+            db.exec(`
+                CREATE TEMP TABLE IF NOT EXISTS epg_programs_staging (
+                    run_id TEXT NOT NULL,
+                    source_id INTEGER NOT NULL,
+                    channel_id TEXT NOT NULL,
+                    start_time INTEGER NOT NULL,
+                    end_time INTEGER NOT NULL,
+                    title TEXT,
+                    description TEXT,
+                    data JSON
+                );
+                CREATE INDEX IF NOT EXISTS temp.idx_epg_programs_staging_run
+                    ON epg_programs_staging(run_id, source_id);
+
+                CREATE TEMP TABLE IF NOT EXISTS epg_channels_staging (
+                    run_id TEXT NOT NULL,
+                    source_id INTEGER NOT NULL,
+                    id TEXT NOT NULL,
+                    item_id TEXT NOT NULL,
+                    name TEXT,
+                    stream_icon TEXT,
+                    data JSON,
+                    PRIMARY KEY (run_id, id)
+                );
+            `);
+
+            const deleteStagedProgrammes = db.prepare(
+                'DELETE FROM temp.epg_programs_staging WHERE run_id = ?'
+            );
+            const deleteStagedChannels = db.prepare(
+                'DELETE FROM temp.epg_channels_staging WHERE run_id = ?'
+            );
+            cleanupRun = () => {
+                deleteStagedProgrammes.run(runId);
+                deleteStagedChannels.run(runId);
+            };
+
+            // A prior interrupted attempt in this process must never be reused.
+            db.prepare('DELETE FROM temp.epg_programs_staging WHERE source_id = ?').run(sourceId);
+            db.prepare('DELETE FROM temp.epg_channels_staging WHERE source_id = ?').run(sourceId);
+
+            const programmeStmt = db.prepare(`
+                INSERT INTO temp.epg_programs_staging (
+                    run_id, source_id, channel_id, start_time, end_time, title, description, data
+                ) VALUES (?, ?, ?, ?, ?, ?, ?, ?)
+            `);
             const channelStmt = db.prepare(`
-                INSERT INTO playlist_items (
+                INSERT INTO temp.epg_channels_staging (
-                    id, source_id, item_id, type, name, stream_icon, 
+                    run_id, source_id, id, item_id, name, stream_icon, data
-                    stream_url, category_id, data
+                ) VALUES (?, ?, ?, ?, ?, ?, ?)
-                )
+                ON CONFLICT(run_id, id) DO UPDATE SET
-                VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)
+                    item_id = excluded.item_id,
-                ON CONFLICT(id) DO UPDATE SET
                     name = excluded.name,
                     stream_icon = excluded.stream_icon,
                     data = excluded.data
             `);
 
-            const insertChannels = db.transaction((chanList) => {
+            const stageProgrammes = db.transaction((programmes) => {
-                for (const ch of chanList) {
+                for (const programme of programmes) {
-                    const id = `${sourceId}:${ch.id}`;
+                    programmeStmt.run(
-                    channelStmt.run(
+                        runId,
-                        id,
                         sourceId,
-                        ch.id,
+                        programme.channelId,
-                        'epg_channel',
+                        programme.start ? programme.start.getTime() : 0,
-                        ch.name,
+                        programme.stop ? programme.stop.getTime() : 0,
-                        ch.icon || null,
+                        programme.title,
-                        null,
+                        programme.description || programme.desc,
-                        null,
+                        JSON.stringify(programme)
-                        JSON.stringify(ch)
+                    );
+                }
+            });
+            const stageChannels = db.transaction((channels) => {
+                for (const channel of channels) {
+                    // EPG channel IDs often overlap Xtream stream IDs. Keep the
+                    // staged row in the same dedicated namespace as the active row.
+                    const id = `${sourceId}:epg_channel:${channel.id}`;
+                    channelStmt.run(
+                        runId,
+                        sourceId,
+                        id,
+                        channel.id,
+                        channel.name,
+                        channel.icon || null,
+                        JSON.stringify(channel)
                     );
                 }
             });
 
-            insertChannels(allChannels);
+            const activateStagedGuide = db.transaction(() => {
-            console.log(`[Sync] Saved ${allChannels.length} EPG channels`);
+                db.prepare('DELETE FROM epg_programs WHERE source_id = ?').run(sourceId);
-        }
+                db.prepare(`
+                    INSERT INTO epg_programs (
+                        channel_id, source_id, start_time, end_time, title, description, data
+                    )
+                    SELECT channel_id, source_id, start_time, end_time, title, description, data
+                    FROM temp.epg_programs_staging
+                    WHERE run_id = ? AND source_id = ?
+                `).run(runId, sourceId);
 
-        console.log(`[Sync] Saved ${totalProgrammes} programmes`);
+                db.prepare(`
+                    DELETE FROM playlist_items
+                    WHERE source_id = ? AND type = 'epg_channel'
+                `).run(sourceId);
+                db.prepare(`
+                    INSERT INTO playlist_items (
+                        id, source_id, item_id, type, name, stream_icon,
+                        stream_url, category_id, data
+                    )
+                    SELECT id, source_id, item_id, 'epg_channel', name, stream_icon,
+                           NULL, NULL, data
+                    FROM temp.epg_channels_staging
+                    WHERE run_id = ? AND source_id = ?
+                `).run(runId, sourceId);
+
+                cleanupRun();
+            });
+
+            const sourceAtStart = await sources.getById(sourceId);
+
+            // Stream into isolated staging tables. The active guide remains
+            // readable throughout download and parsing.
+            for await (const batch of epgParser.fetchAndParseStreaming(url)) {
+                batchCount++;
+                skippedProgrammes += batch.skippedProgrammes || 0;
+
+                if (batch.channels !== null && batch.channels !== undefined) {
+                    stageChannels(batch.channels);
+                    totalChannels += batch.channels.length;
+                }
+
+                if (batch.programmes.length > 0) {
+                    stageProgrammes(batch.programmes);
+                    totalProgrammes += batch.programmes.length;
+                }
+
+                if (batch.isLast) sawFinalBatch = true;
+
+                if (batchCount % 10 === 0) {
+                    console.log(`[Sync] Staged ${totalProgrammes} programmes so far...`);
+                    logMemory();
+                }
+
+                // Keep requests responsive between SQLite batches.
+                await new Promise(resolve => setImmediate(resolve));
+            }
+
+            if (!sawFinalBatch) {
+                throw new Error('EPG refresh ended before the XMLTV document completed');
+            }
+
+            // If a real configured source disappeared while its download was
+            // running, do not recreate any of its guide data.
+            const sourceStillExists = !sourceAtStart || await sources.getById(sourceId);
+            const sourceWasInvalidated = (epgSourceGenerations.get(sourceKey) || 0) !== sourceGeneration;
+            if (sourceWasInvalidated || !sourceStillExists) {
+                throw new Error(`EPG source ${sourceId} was removed during refresh`);
+            }
+
+            console.log(`[Sync] EPG Parsed: ${totalChannels} channels, ${totalProgrammes} programmes`);
+            if (skippedProgrammes > 0) {
+                console.warn(`[Sync] Skipped ${skippedProgrammes} programme entries with invalid XMLTV timestamps`);
+            }
+            logMemory();
+
+            // One short transaction makes programmes and channel mapping
+            // visible together. A valid empty feed intentionally clears both.
+            activateStagedGuide();
+            console.log(`[Sync] Activated ${totalChannels} EPG channels and ${totalProgrammes} programmes`);
+        } catch (error) {
+            refreshError = error;
+            throw error;
+        } finally {
+            try {
+                if (cleanupRun) cleanupRun();
+            } catch (cleanupError) {
+                console.warn('[Sync] Failed to clean EPG staging data:', cleanupError.message);
+                if (!refreshError) throw cleanupError;
+            } finally {
+                activeEpgSyncs.delete(sourceKey);
+            }
+        }
     }
 
     /**

server/services/xmltvDate.js

@@ -0,0 +1,94 @@
+function createValidatedCalendarDate(year, month, day, hour, minute, second) {
+    if (
+        month < 1 || month > 12 ||
+        day < 1 || day > 31 ||
+        hour < 0 || hour > 23 ||
+        minute < 0 || minute > 59 ||
+        second < 0 || second > 59
+    ) {
+        return null;
+    }
+
+    // setUTCFullYear avoids Date.UTC's special handling of years 0-99.
+    const calendarDate = new Date(0);
+    calendarDate.setUTCFullYear(year, month - 1, day);
+    calendarDate.setUTCHours(hour, minute, second, 0);
+
+    // Date normalizes impossible calendar values (for example February 30),
+    // so compare every component before accepting it.
+    if (
+        calendarDate.getUTCFullYear() !== year ||
+        calendarDate.getUTCMonth() !== month - 1 ||
+        calendarDate.getUTCDate() !== day ||
+        calendarDate.getUTCHours() !== hour ||
+        calendarDate.getUTCMinutes() !== minute ||
+        calendarDate.getUTCSeconds() !== second
+    ) {
+        return null;
+    }
+
+    return calendarDate;
+}
+
+function parseTimezoneOffset(timezone) {
+    if (!timezone || timezone.toUpperCase() === 'Z') return 0;
+
+    const normalized = timezone.replace(':', '');
+    const offsetHours = Number(normalized.slice(1, 3));
+    const offsetRemainder = Number(normalized.slice(3, 5));
+    if (offsetHours > 23 || offsetRemainder > 59) return null;
+
+    const total = (offsetHours * 60) + offsetRemainder;
+    return normalized[0] === '-' ? -total : total;
+}
+
+/**
+ * Parse an XMLTV date/time. XMLTV permits YYYYMMDDHHmmss or a shorter
+ * initial precision (for example YYYYMMDDHHmm, YYYYMMDDHH, or YYYYMMDD).
+ * Missing components use the earliest value in that precision and UTC is
+ * assumed when no numeric offset is provided.
+ * @param {string} dateStr - XMLTV format date string
+ * @returns {Date|null}
+ */
+function parseXmltvDate(dateStr) {
+    if (!dateStr) return null;
+
+    const value = String(dateStr).trim();
+    const match = value.match(/^(\d{4}(?:\d{2}){0,5})\s*(Z|[+-]\d{4})?$/i);
+    if (!match) {
+        // Preserve the existing compatibility fallback for explicit ISO 8601
+        // timestamps without accepting arbitrary host-dependent date strings.
+        const isoMatch = value.match(/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2})(?::(\d{2})(?:\.\d{1,3})?)?(Z|[+-]\d{2}:?\d{2})$/i);
+        if (!isoMatch) return null;
+
+        const [, year, month, day, hour, minute, second = '0', timezone] = isoMatch;
+        if (!createValidatedCalendarDate(
+            Number(year),
+            Number(month),
+            Number(day),
+            Number(hour),
+            Number(minute),
+            Number(second)
+        ) || parseTimezoneOffset(timezone) === null) return null;
+
+        const isoDate = new Date(value);
+        return Number.isNaN(isoDate.getTime()) ? null : isoDate;
+    }
+
+    const digits = match[1];
+    const timezone = match[2]?.toUpperCase();
+    const year = Number(digits.slice(0, 4));
+    const month = digits.length >= 6 ? Number(digits.slice(4, 6)) : 1;
+    const day = digits.length >= 8 ? Number(digits.slice(6, 8)) : 1;
+    const hour = digits.length >= 10 ? Number(digits.slice(8, 10)) : 0;
+    const minute = digits.length >= 12 ? Number(digits.slice(10, 12)) : 0;
+    const second = digits.length >= 14 ? Number(digits.slice(12, 14)) : 0;
+
+    const calendarDate = createValidatedCalendarDate(year, month, day, hour, minute, second);
+    const offsetMinutes = parseTimezoneOffset(timezone);
+    if (!calendarDate || offsetMinutes === null) return null;
+
+    return new Date(calendarDate.getTime() - (offsetMinutes * 60 * 1000));
+}
+
+module.exports = { parseXmltvDate };

test/epg-refresh.test.js

@@ -0,0 +1,241 @@
+const test = require('node:test');
+const assert = require('node:assert/strict');
+const fs = require('node:fs');
+const os = require('node:os');
+const path = require('node:path');
+const vm = require('node:vm');
+const http = require('node:http');
+const zlib = require('node:zlib');
+const { Readable } = require('node:stream');
+const { createRequire } = require('node:module');
+const parser = require('../server/services/epgParser');
+
+const programme = (title, channel = '1') => `<programme channel="${channel}" start="202607140600 +0000" stop="202607140700 +0000"><title>${title}</title></programme>`;
+const channel = (id = '1', name = 'Guide channel') => `<channel id="${id}"><display-name>${name}</display-name></channel>`;
+const guide = (title = 'Old', id = '1') => `<tv>${channel(id)}${programme(title, id)}</tv>`;
+
+async function collect(input, batchSize = 7) {
+    const result = { channels: [], programmes: [], skipped: 0, final: 0 };
+    for await (const batch of parser.parseStreaming(input, batchSize)) {
+        assert.ok(batch.programmes.length <= batchSize);
+        assert.ok(batch.channels.length <= batchSize);
+        result.channels.push(...batch.channels);
+        result.programmes.push(...batch.programmes);
+        result.skipped += batch.skippedProgrammes;
+        result.final += Number(batch.isLast);
+    }
+    return result;
+}
+
+test('XMLTV accepts reduced precision and rejects impossible timestamps', async () => {
+    for (const [value, expected] of [
+        ['20260714061234 +0000', '2026-07-14T06:12:34.000Z'],
+        ['202607140612 +0000', '2026-07-14T06:12:00.000Z'],
+        ['2026071406 -0500', '2026-07-14T11:00:00.000Z'],
+        ['20260714 +0230', '2026-07-13T21:30:00.000Z'],
+        ['202607', '2026-07-01T00:00:00.000Z'], ['2026', '2026-01-01T00:00:00.000Z'],
+        ['20260714061234Z', '2026-07-14T06:12:34.000Z'],
+        ['2026-07-14T06:12:34+02:00', '2026-07-14T04:12:34.000Z']
+    ]) assert.equal(parser.parseXmltvDate(value).toISOString(), expected, value);
+    for (const value of ['', 'garbage', '20260230060000 +0000', '20261301060000',
+        '20260714240000', '20260714066000', '20260714060060', '20260714060000 +2460',
+        '20260714060 +0000', '2026-02-30T06:00:00Z']) assert.equal(parser.parseXmltvDate(value), null, value);
+    const xml = `<tv>${channel()}${programme('Valid')}${programme('Invalid').replace('202607140600', '202602300600')}</tv>`;
+    assert.equal((await parser.parse(xml)).programmes.length, 1);
+    const streamed = await collect(xml);
+    assert.equal(streamed.programmes.length, 1);
+    assert.equal(streamed.skipped, 1);
+});
+
+test('streaming XMLTV retains every batch in one chunk and channels arriving after programmes', async () => {
+    const titles = Array.from({ length: 2501 }, (_, i) => `Programme ${i}`);
+    const xml = `<tv>${channel()}${titles.map(title => programme(title)).join('')}${channel('10', 'Late')}</tv>`;
+    const result = await collect(Readable.from([Buffer.from(xml)]));
+    assert.deepEqual(result.programmes.map(p => p.title), titles);
+    assert.deepEqual(result.channels.map(c => c.id), ['1', '10']);
+    assert.equal(result.final, 1);
+    const unicode = Buffer.from(guide('Café 東京'));
+    const split = await collect(Readable.from(Array.from(unicode, byte => Buffer.from([byte]))));
+    assert.equal(split.programmes[0].title, 'Café 東京');
+});
+
+test('both XMLTV parsers reject malformed or incomplete documents and propagate stream errors', async () => {
+    for (const xml of ['', '<html>Failure</html>', '<tv>', `<tv>${programme('Partial')}`,
+        '<tv><channel id="1"></tv>', '<tv/><tv/>']) {
+        await assert.rejects(parser.parse(xml), /XMLTV/);
+        await assert.rejects(collect(xml), /XMLTV/);
+    }
+    const broken = () => Readable.from((async function* () { yield '<tv>'; throw new Error('Network interrupted'); })());
+    await assert.rejects(parser.parse(broken()), /Network interrupted/);
+    await assert.rejects(collect(broken()), /Network interrupted/);
+});
+
+function fixture(t, epg = parser) {
+    const dir = fs.mkdtempSync(path.join(os.tmpdir(), 'nodecast-epg-test-'));
+    const filename = path.join(__dirname, '..', 'server/db/sqlite.js');
+    const sqliteModule = { exports: {} };
+    vm.runInNewContext(fs.readFileSync(filename, 'utf8'), { module: sqliteModule,
+        require: createRequire(filename), __dirname: path.dirname(filename),
+        process: { env: { NODECAST_DATA_DIR: dir } }, console: { log() {} } }, { filename });
+    const db = sqliteModule.exports.getDb();
+    t.after(() => {
+        db.close();
+        assert.equal(path.dirname(path.resolve(dir)), path.resolve(os.tmpdir()));
+        fs.rmSync(dir, { recursive: true, force: true });
+    });
+    const configured = new Map([[1, { id: 1 }], [2, { id: 2 }]]);
+    const sources = { getById: async id => configured.get(Number(id)), delete: async id => configured.delete(Number(id)) };
+    const syncFile = path.join(__dirname, '..', 'server/services/syncService.js');
+    const syncModule = { exports: {} }, realRequire = createRequire(syncFile);
+    vm.runInNewContext(fs.readFileSync(syncFile, 'utf8'), { module: syncModule, URL, process, setImmediate,
+        console: { log() {}, warn() {} }, require(id) {
+            if (id === '../db/sqlite') return { getDb: () => db };
+            if (id === '../db') return { sources, settings: {} };
+            if (id === './epgParser') return epg;
+            if (id === './xtreamApi' || id === './m3uParser') return {};
+            return realRequire(id);
+        } }, { filename: syncFile });
+    const sync = syncModule.exports;
+    const snapshot = sourceId => ({
+        programmes: db.prepare('SELECT channel_id,title,start_time,end_time FROM epg_programs WHERE source_id=? ORDER BY title').all(sourceId),
+        channels: db.prepare("SELECT id,item_id,name FROM playlist_items WHERE source_id=? AND type='epg_channel' ORDER BY id").all(sourceId)
+    });
+    const stagedCount = () => db.prepare('SELECT COUNT(*) AS count FROM temp.epg_programs_staging').get().count
+        + db.prepare('SELECT COUNT(*) AS count FROM temp.epg_channels_staging').get().count;
+    return { db, sync, sources, configured, snapshot, stagedCount };
+}
+
+async function origin(t, handler) {
+    const server = http.createServer(handler);
+    await new Promise(resolve => server.listen(0, '127.0.0.1', resolve));
+    t.after(() => new Promise(resolve => { server.close(resolve); server.closeAllConnections(); }));
+    return `http://127.0.0.1:${server.address().port}`;
+}
+
+test('EPG replacement preserves live media and other sources while clearing stale guide entries', async t => {
+    const { db, sync, snapshot, stagedCount } = fixture(t);
+    let xml = guide();
+    const base = await origin(t, (req, res) => res.end(xml));
+    const insert = db.prepare('INSERT INTO playlist_items (id,source_id,item_id,type,name,stream_url,data) VALUES (?,?,?,?,?,?,?)');
+    for (const id of ['1', '10']) insert.run(`1:${id}`, 1, id, 'live', `Live ${id}`, `http://provider.test/${id}`, '{"retained":true}');
+    insert.run('1:legacy', 1, 'legacy', 'epg_channel', 'Legacy guide', null, '{}');
+    const liveBefore = db.prepare("SELECT * FROM playlist_items WHERE type='live' ORDER BY id").all();
+    await sync.syncEpgFromUrl(2, base);
+    const otherBefore = snapshot(2);
+    xml = `<tv>${channel('1')}${channel('10')}${programme('Fresh', '10')}</tv>`;
+    await sync.syncEpgFromUrl(1, base);
+    assert.deepEqual(db.prepare("SELECT * FROM playlist_items WHERE type='live' ORDER BY id").all(), liveBefore);
+    assert.deepEqual(snapshot(1).channels.map(c => c.id), ['1:epg_channel:1', '1:epg_channel:10']);
+    assert.equal(snapshot(1).programmes[0].title, 'Fresh');
+    assert.deepEqual(snapshot(2), otherBefore);
+    xml = '<tv/>';
+    await sync.syncEpgFromUrl(1, base);
+    assert.deepEqual(snapshot(1), { programmes: [], channels: [] });
+    assert.deepEqual(db.prepare("SELECT * FROM playlist_items WHERE type='live' ORDER BY id").all(), liveBefore);
+    assert.equal(stagedCount(), 0);
+});
+
+test('failed XML, gzip, HTTP and interrupted downloads preserve the complete previous guide', async t => {
+    const { sync, snapshot, stagedCount } = fixture(t);
+    const prefix = `<tv>${channel()}${Array.from({ length: 1001 }, (_, i) => programme(`New ${i}`)).join('')}`;
+    const base = await origin(t, (req, res) => {
+        if (req.url === '/good') res.end(guide());
+        else if (req.url === '/truncated') res.end(prefix);
+        else if (req.url === '/bad.gz') res.end(Buffer.from([0x1f, 0x8b, 0, 0, 0]));
+        else if (req.url === '/http') { res.writeHead(503); res.end('Unavailable'); }
+        else { res.writeHead(200, { 'Content-Length': Buffer.byteLength(prefix) + 100 }); res.write(prefix); setImmediate(() => res.destroy()); }
+    });
+    await sync.syncEpgFromUrl(1, `${base}/good`);
+    const old = snapshot(1);
+    for (const suffix of ['truncated', 'bad.gz', 'http', 'interrupted']) {
+        await assert.rejects(sync.syncEpgFromUrl(1, `${base}/${suffix}`));
+        assert.deepEqual(snapshot(1), old, suffix);
+        assert.equal(stagedCount(), 0, suffix);
+    }
+    await sync.syncEpgFromUrl(1, `${base}/good`);
+    assert.deepEqual(snapshot(1), old);
+});
+
+test('gzip downloads and transparent HTTP gzip decode once, including split magic bytes', async t => {
+    const { sync, snapshot } = fixture(t);
+    const compressed = zlib.gzipSync(guide('Compressed'));
+    const base = await origin(t, (req, res) => {
+        if (req.url === '/encoded.gz') res.setHeader('Content-Encoding', 'gzip');
+        res.write(compressed.subarray(0, 1));
+        setImmediate(() => res.end(compressed.subarray(1)));
+    });
+    for (const suffix of ['download.gz?token=test', 'encoded.gz']) {
+        await sync.syncEpgFromUrl(1, `${base}/${suffix}`);
+        assert.equal(snapshot(1).programmes[0].title, 'Compressed');
+    }
+    assert.equal((await parser.fetchAndParse(`${base}/encoded.gz`)).programmes[0].title, 'Compressed');
+});
+
+test('different sources can refresh concurrently without mixing staged data', async t => {
+    const { sync, snapshot, stagedCount } = fixture(t);
+    const base = await origin(t, (req, res) => res.end(`<tv>${channel()}${Array.from({ length: 1101 }, (_, i) => programme(`${req.url}-${i}`)).join('')}</tv>`));
+    await Promise.all([sync.syncEpgFromUrl(1, `${base}/one`), sync.syncEpgFromUrl(2, `${base}/two`)]);
+    for (const [sourceId, prefix] of [[1, '/one-'], [2, '/two-']]) {
+        const data = snapshot(sourceId);
+        assert.equal(data.programmes.length, 1101);
+        assert.ok(data.programmes.every(p => p.title.startsWith(prefix)));
+        assert.equal(data.channels.length, 1);
+    }
+    assert.equal(stagedCount(), 0);
+});
+
+test('activation is atomic, rolls back SQL failures, and serializes same-source refreshes', async t => {
+    let streamFactory = async function* () { yield* parser.parseStreaming(guide()); };
+    const epg = { fetchAndParseStreaming: (...args) => streamFactory(...args) };
+    const { db, sync, snapshot, stagedCount } = fixture(t, epg);
+    const url = 'http://provider.test/guide';
+    await sync.syncEpgFromUrl(1, url);
+    const old = snapshot(1);
+    streamFactory = async function* () {
+        for await (const batch of parser.parseStreaming(guide('New', '10'), 1)) {
+            yield batch;
+            assert.deepEqual(snapshot(1), old);
+            await assert.rejects(sync.syncEpgFromUrl(1, url), /already in progress/);
+        }
+    };
+    db.exec("CREATE TRIGGER fail_guide BEFORE INSERT ON playlist_items WHEN NEW.type='epg_channel' BEGIN SELECT RAISE(ABORT,'activation failed'); END;");
+    await assert.rejects(sync.syncEpgFromUrl(1, url), /activation failed/);
+    assert.deepEqual(snapshot(1), old);
+    assert.equal(stagedCount(), 0);
+    db.exec('DROP TRIGGER fail_guide');
+    await sync.syncEpgFromUrl(1, url);
+    assert.equal(snapshot(1).programmes[0].title, 'New');
+});
+
+test('deleting a source through its route invalidates an in-flight guide refresh', async t => {
+    let release, staged;
+    const paused = new Promise(resolve => { staged = resolve; });
+    const gate = new Promise(resolve => { release = resolve; });
+    const epg = { async *fetchAndParseStreaming() {
+        for await (const batch of parser.parseStreaming(guide('Deleted'), 1)) {
+            yield batch;
+            if (!batch.isLast) { staged(); await gate; }
+        }
+    } };
+    const { db, sync, sources, snapshot, stagedCount } = fixture(t, epg);
+    const filename = path.join(__dirname, '..', 'server/routes/sources.js');
+    let deleteRoute;
+    const router = { get() {}, post() {}, put() {}, delete(route, handler) { deleteRoute = handler; } };
+    vm.runInNewContext(fs.readFileSync(filename, 'utf8'), { module: { exports: {} }, console: { log() {}, error() {} }, require(id) {
+        if (id === 'express') return { Router: () => router };
+        if (id === '../db') return { sources };
+        if (id === '../db/sqlite') return { getDb: () => db };
+        if (id === '../services/syncService') return sync;
+        return {};
+    } }, { filename });
+    const refreshing = sync.syncEpgFromUrl(1, 'http://provider.test/guide');
+    const rejected = assert.rejects(refreshing, /removed during refresh/);
+    await paused;
+    const res = { status(code) { this.code = code; return this; }, json(value) { this.value = value; } };
+    await deleteRoute({ params: { id: '1' } }, res);
+    assert.equal(res.value.success, true);
+    release();
+    await rejected;
+    assert.deepEqual(snapshot(1), { programmes: [], channels: [] });
+    assert.equal(stagedCount(), 0);
+});