feat: support the music cache limit

src/main/api/cache.js

@@ -8,8 +8,9 @@ class Cache {
     /**
      * @param {string} path cache directory path
      * @param {string} configPath config directory path
+     * @param {number} cacheLimitcache size limit in bytes. 0 means unlimited
      */
-    constructor(path, configPath) {
+    constructor(path, configPath, cacheLimit) {
         if (typeof path === 'string') {
             if (!fs.existsSync(path)) {
                 fs.mkdirSync(path);
@@ -34,6 +35,7 @@ class Cache {
         } else {
             throw new Error('Cache path unvalid');
         }
+        this.cacheLimit = cacheLimit;
     }
 
     attachExternalCache(fileName, filePath) {
@@ -56,7 +58,35 @@ class Cache {
         return path.join(this.path, String(fileName));
     }
 
+    async setCacheLimit(newSize) {
+        this.cacheLimit = newSize;
+        this.spareSpace();
+    }
+
+    /**
+     * delete cache until cache size <= limit
+     */
+    spareSpace() {
+        if (this.cacheLimit === 0) return;
+
+        const stats = fs.readdirSync(this.path)
+                        .map(f => ({name: f, attr: fs.statSync(path.join(this.path, f))}))
+                        .filter(f => f.attr.isFile());
+        let diskUsage = stats.reduce((x, y)=> x + y.attr.size, 0);
+        if (diskUsage <= this.cacheLimit)
+            return;
+        stats.sort((a, b)=> a.attr.atime < b.attr.atime);
+        for (const st of stats) {
+            const size = st.attr.size;
+            diskUsage -= size;
+            fs.unlinkSync(path.join(this.path, st.name));
+            if (diskUsage <= this.cacheLimit)
+                break;
+        }
+    }
+
     writeStream(fileName) {
+        this.spareSpace();
         return fs.createWriteStream(this.internalPath(fileName));
     }
 

src/main/api/index.js

@@ -24,7 +24,7 @@ const CachePath = {
     all: dataPath,
     music: path.join(dataPath, 'musicCache')
 };
-const musicCache = new Cache(CachePath.music, dataPath);
+const musicCache = new Cache(CachePath.music, dataPath, Settings.getSync().musicCacheLimit*1024*1024);
 migrate();
 
 const musicServer = new MusicServer(musicCache);
@@ -530,6 +530,22 @@ export async function clearCache(type) {
     return { ok: true };
 }
 
+/**
+ * @param {Types.CacheType} size cache limit in bytes
+ * @returns {Promise<{ok: boolean; msg?: string}>}
+ */
+export async function setMusicCacheLimit(size) {
+    try {
+        await musicServer.cache.setCacheLimit(size);
+    } catch (e) {
+        return {
+            ok: false,
+            msg: e.stack
+        };
+    }
+    return { ok: true };
+}
+
 /**
  * @returns {Promise<string>}
  */

src/main/api/musicServer.js

@@ -153,7 +153,7 @@ class MusicServer {
             d('Got URL for music id=%d', id);
             const musicRes = await this.cache.fetch(music.url.replace(/^http:/, 'https:'));
             // TODO: write file only md5 matches
-            musicRes.body.pipe(fs.createWriteStream(this.cache.internalPath(fileName)));
+            musicRes.body.pipe(this.cache.writeStream(fileName));
 
             const range = MusicServer.getRange(req, +musicRes.headers.get('content-length'));
             res.writeHead(206, MusicServer.buildHeaders(range));

src/main/settings.js

@@ -24,7 +24,8 @@ export const defaultSettings = {
     themePrimaryColor: '#7e57c2',
     themeSecondaryColor: '#ff4081',
     themeVariety: 'auto',
-    autoReplacePlaylist: false
+    autoReplacePlaylist: false,
+    musicCacheLimit: 512,
 };
 
 /**
@@ -44,10 +45,18 @@ function writeFile(target) {
     return fsp.writeFile(configPath, JSON.stringify(target, null, 4), 'utf8');
 }
 
+function writeFileSync(target) {
+    return fs.writeFileSync(configPath, JSON.stringify(target, null, 4), 'utf8');
+}
+
 function readFile() {
     return fsp.readFile(configPath, 'utf8');
 }
 
+function readFileSync() {
+    return fs.readFileSync(configPath, 'utf8');
+}
+
 export async function set(target) {
     try {
         await fsp.access(configDir);
@@ -57,6 +66,15 @@ export async function set(target) {
     return writeFile(target);
 }
 
+export function setSync(target) {
+    try {
+        fs.accessSync(configDir);
+    } catch (e) {
+        fs.mkdirSync(configDir);
+    }
+    return writeFileSync(target);
+}
+
 export async function get() {
     let settings = defaultSettings;
     try {
@@ -68,3 +86,15 @@ export async function get() {
     }
     return settings;
 }
+
+export function getSync() {
+    let settings = defaultSettings;
+    try {
+        fs.accessAsync(configPath);
+        const json = JSON.parse(readFileSync());
+        settings = trimSettings(json);
+    } catch (e) {
+        setSync(defaultSettings);
+    }
+    return settings;
+}

src/renderer/page/Settings/Settings.vue

@@ -81,6 +81,10 @@ export default {
             Api.getDataSize('all').then(s => this.dataSize = humanSize(s.size));
             Api.getDataSize('music').then(s => this.musicSize = humanSize(s.size));
         },
+        setMusicCacheLimit(size) {
+            Api.setMusicCacheLimit(size);
+            Api.getDataSize('music').then(s => this.musicSize = humanSize(s.size));
+        },
         initData() {
             this.refreshSize();
             Api.getVersionName().then(v => this.versionName = v);
@@ -201,6 +205,9 @@ export default {
                                 this.$toast.message('实际下载码率取决于歌曲最高码率和帐号最高可播放码率');
                             }
                             break;
+                        case 'musicCacheLimit':
+                            this.setMusicCacheLimit(val*1024*1024);
+                            break;
                     }
                 }
             });

src/renderer/page/Settings/entries.js

@@ -163,6 +163,18 @@ export const Entries = [
                 data: 'musicSize',
                 handler: 'promptClearMusicCache'
             },
+            {
+                type: 'select',
+                title: '歌曲缓存空间限制',
+                prop: 'musicCacheLimit',
+                options: [
+                    { label: '无限制', value: 0 },
+                    { label: '128 MiB', value: 128 },
+                    { label: '256 MiB', value: 256 },
+                    { label: '512 MiB', value: 512 },
+                    { label: '1 GiB', value: 1024 },
+                ]
+            },
             {
                 type: 'plain',
                 title: '所有应用数据',