It's maybe a bug for clear target by using okhttp3

[zaydenyang]

0. the problem:

The function of GlideApp.with(context).clear(target); was invoked when I try to cancel a url-request. It expected that the url-request was canceled but I found the callback function of target which is named onLoadCleared() worked while the url-request was still in the queue of okhttp3 and it still could load the bitmap from internet. I think it seemed to be a bug.

1. my dependencies:

    implementation 'com.squareup.okio:okio:2.1.0'
    implementation 'com.squareup.okhttp3:okhttp:3.11.0'
    implementation 'com.jakewharton:disklrucache:2.0.2'
    implementation 'com.github.bumptech.glide:glide:4.8.0'
    annotationProcessor 'com.github.bumptech.glide:compiler:4.8.0'
    implementation 'com.github.bumptech.glide:okhttp3-integration:4.8.0'

2. my test code:

    // DemoAppGlideModule.java
    @Override
    public void registerComponents(@NonNull Context context, @NonNull Glide glide, @NonNull Registry registry) {
        super.registerComponents(context, glide, registry);
        OkHttpClient client = new OkHttpClient.Builder()
                .connectTimeout(5, TimeUnit.SECONDS)
                .readTimeout(10, TimeUnit.SECONDS)
                .writeTimeout(10, TimeUnit.SECONDS)
                .retryOnConnectionFailure(false)
                .build();
        registry.replace(GlideUrl.class, InputStream.class, new OkHttpUrlLoader.Factory(client));
    }

   // MainActivity.java
    @Override
    protected void onResume() {
        super.onResume();
        Random random = new Random();
        new Thread() {
            @Override
            public void run() {
                super.run();
                // pathSet contains some urls
                Iterator<String> iterator = pathSet.iterator();
                while (iterator.hasNext()) {
                    final String path = iterator.next();
                    // DemoGlideTarget extends SimpleTarget<Drawable>, do nothing but just show log of callback 
                    final DemoGlideTarget target = new DemoGlideTarget(500, 500, path, null, false);
                    UIHANDLER.post(new Runnable() {
                        @Override
                        public void run() {
                            GlideApp.with(MainActivity.this).load(path).skipMemoryCache(true).diskCacheStrategy(DiskCacheStrategy.NONE).into(target);
                        }
                    });
                    UIHANDLER.postDelayed(new Runnable() {
                        @Override
                        public void run() {
                            GlideApp.with(MainActivity.this).clear(target);
                        }
                    }, 60 + random.nextInt(500));

                    try {
                        Thread.sleep(random.nextInt(100));
                    } catch (Throwable e) {
                    }
                }
            }
        }.start();
    }

3. my analyze:

When use registry.replace(GlideUrl.class, InputStream.class, new OkHttpUrlLoader.Factory(client));, the MultiModelLoader.MultiFetcher.fetchers contains UrlUriLoader's fetcher and HttpUriLoader's fetcher, so it will create two OkHttpStreamFetcher for each of the url-requests, and the UrlUriLoader's fetcher excutes first. When cancel(clear target) occurs, the OkHttpStreamFetcher.cancel() works, and then comes OkHttpStreamFetcher.onFailure("Cancle"). Eventually MultiFetcher.startNextOrFail() will be called and the HttpUriLoader's fetcher will enqueue a new request into okhttp3's queue although the url-request should have been canceled.

Please check for that?