Use stored metadata when offline

Author: ajungg

core/src/main/java/io/snabble/sdk/MetadataDownloader.java

@@ -1,7 +1,5 @@
 package io.snabble.sdk;
 
-import android.os.Bundle;
-
 import com.google.gson.Gson;
 import com.google.gson.JsonObject;
 import com.google.gson.JsonSyntaxException;
@@ -23,15 +21,19 @@ class MetadataDownloader extends StringDownloader {
     private JsonObject metadata;
     private JsonObject project;
 
+    private boolean hasData = false;
+
     public MetadataDownloader(SnabbleSdk sdk,
                               String bundledFileAssetPath) {
         super(sdk.getOkHttpClient());
 
         this.sdk = sdk;
+        File storageFile = new File(sdk.getInternalStorageDirectory(), "metadata.json");
 
         if (bundledFileAssetPath != null) {
-            setBundledData(sdk.getApplication(), bundledFileAssetPath,
-                    new File(sdk.getInternalStorageDirectory(), "metadata.json"));
+            setBundledData(sdk.getApplication(), bundledFileAssetPath, storageFile);
+        } else {
+            setStorageFile(storageFile);
         }
 
         setUrl(sdk.getMetadataUrl());
@@ -42,8 +44,6 @@ protected void onDownloadFinished(String content) {
         try {
             Map<String, String> urls = new HashMap<>();
             Map<String, String> extras = new HashMap<>();
-            Bundle flags = new Bundle();
-            Bundle projectSettings = new Bundle();
 
             Gson gson = new Gson();
             JsonObject jsonObject = gson.fromJson(content, JsonObject.class);
@@ -73,11 +73,16 @@ protected void onDownloadFinished(String content) {
             this.extras = Collections.unmodifiableMap(extras);
 
             updateStorage(content);
+            hasData = true;
         } catch (JsonSyntaxException e){
             Logger.e(e.getMessage());
         }
     }
 
+    public boolean hasData() {
+        return hasData;
+    }
+
     public Map<String, String> getUrls() {
         return urls;
     }

core/src/main/java/io/snabble/sdk/SnabbleSdk.java

@@ -298,7 +298,11 @@ protected void onDataLoaded(boolean wasStillValid) {
 
                 @Override
                 protected void onError() {
-                    setupError(setupCompletionListener, Error.CONNECTION_TIMEOUT);
+                    if(metadataDownloader.hasData()){
+                        setupSdk(config, setupCompletionListener);
+                    } else {
+                        setupError(setupCompletionListener, Error.CONNECTION_TIMEOUT);
+                    }
                 }
             });
         }

utils/src/main/java/io/snabble/sdk/utils/StringDownloader.java

@@ -42,11 +42,8 @@ public void setBundledData(Context context, String assetPath, File storageFile)
             //so we check for the install time of the app
             //this implicitly means that while developing you always start with the seeded data
             //and that app updates should always contain updated seeds
-            if (storageFile.exists() && storageFile.lastModified() > packageInfo.lastUpdateTime) {
-                FileInputStream fis = new FileInputStream(this.storageFile);
-                Logger.d("Using saved data: %s", storageFile.getAbsolutePath());
-                onDownloadFinished(IOUtils.toString(fis, Charset.forName("UTF-8")));
-                fis.close();
+            if(storageFile.exists() && storageFile.lastModified() > packageInfo.lastUpdateTime) {
+                loadFromSavedData();
             } else {
                 Logger.d("Using initial seed: %s", storageFile.getAbsolutePath());
                 onDownloadFinished(IOUtils.toString(bundledDataInputStream, Charset.forName("UTF-8")));
@@ -56,8 +53,23 @@ public void setBundledData(Context context, String assetPath, File storageFile)
         }
     }
 
+    private void loadFromSavedData() throws IOException {
+        FileInputStream fis = new FileInputStream(storageFile);
+        Logger.d("Using saved data: %s", storageFile.getAbsolutePath());
+        onDownloadFinished(IOUtils.toString(fis, Charset.forName("UTF-8")));
+        fis.close();
+    }
+
     public void setStorageFile(File storageFile) {
         this.storageFile = storageFile;
+
+        if (storageFile.exists()) {
+            try {
+                loadFromSavedData();
+            } catch (IOException e) {
+                Logger.e("Could not load saved data: %s", storageFile.getAbsolutePath());
+            }
+        }
     }
 
     /**
@@ -88,8 +100,6 @@ protected void onResponse(Response response) throws IOException {
         if (body != null) {
             onDownloadFinished(body.string());
             Logger.d("Received data for %s", getUrl());
-        } else {
-            Logger.d("Error receiving data for %s", getUrl());
         }
     }