Starting model manager for sdAlgNn

app/src/main/java/uk/org/openseizuredetector/MlModelManager.java

@@ -0,0 +1,112 @@
+package uk.org.openseizuredetector;
+
+import android.content.Context;
+import android.os.Handler;
+import android.util.Log;
+
+import com.android.volley.AuthFailureError;
+import com.android.volley.Request;
+import com.android.volley.RequestQueue;
+import com.android.volley.Response;
+import com.android.volley.VolleyError;
+import com.android.volley.VolleyLog;
+import com.android.volley.toolbox.StringRequest;
+import com.android.volley.toolbox.Volley;
+
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import java.io.UnsupportedEncodingException;
+import java.text.DateFormat;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+import java.util.HashMap;
+import java.util.Map;
+
+
+// This class manages machine learning models by downloading them from a remote server when necessary.
+public class MlModelManager {
+    protected Context mContext;
+    protected OsdUtil mUtil;
+    private String TAG = "MlModelManager";
+
+    public boolean mServerConnectionOk = false;
+    public boolean mModelReady = false;
+    private final String mUrlBase = "https://openseizuredetector.org.uk/static/MLmodels/";
+    private final String mModelIndexFname = "MLmodels.json";
+   RequestQueue mQueue;
+
+    public interface JSONObjectCallback {
+        public void accept(JSONObject retValObj);
+    }
+
+
+    public MlModelManager(Context context) {
+        Log.i(TAG,"MlModelManager Constructor");
+        mContext = context;
+        mUtil = new OsdUtil(mContext, new Handler());
+        mQueue = Volley.newRequestQueue(mContext);
+    }
+
+    public void close() {
+        Log.i(TAG, "close()");
+        mQueue.stop();
+    }
+
+
+
+    /**
+     * Retrieve the file containing the list of available ML models from the server.
+     * Calls the specified callback function, passing a JSONObject as a parameter when the data has been received and parsed.
+     *
+     * @return true if request sent successfully or else false.
+     */
+    public boolean getMlModelIndex(JSONObjectCallback callback) {
+        Log.v(TAG, "getMlModelIndex()");
+        String urlStr = mUrlBase + mModelIndexFname;
+        Log.v(TAG, "urlStr=" + urlStr);
+
+        StringRequest req = new StringRequest(Request.Method.GET, urlStr,
+                new Response.Listener<String>() {
+                    @Override
+                    public void onResponse(String response) {
+                        Log.v(TAG, "getMlModelIndex.onResponse(): Response is: " + response);
+                        mServerConnectionOk = true;
+                        try {
+                            JSONObject retObj = new JSONObject(response);
+                            callback.accept(retObj);
+                        } catch (JSONException e) {
+                            Log.e(TAG, "getMlModelIndex.onRespons(): Error: " + e.getMessage() + "," + e.toString());
+                            callback.accept(null);
+                        }
+                    }
+                },
+                new Response.ErrorListener() {
+                    @Override
+                    public void onErrorResponse(VolleyError error) {
+                        mServerConnectionOk = false;
+                        if (error != null) {
+                            Log.e(TAG, "getMlModelIndex.onErrorResponse(): " + error.toString() + ", message:" + error.getMessage());
+                        } else {
+                            Log.e(TAG, "getMlModelIndex.onErrorResponse() - returned null response");
+                        }
+                        callback.accept(null);
+                    }
+                }) {
+            // Note, this is overriding part of StringRequest, not one of the sub-classes above!
+            @Override
+            public Map<String, String> getHeaders() throws AuthFailureError {
+                Map<String, String> params = new HashMap<String, String>();
+                params.put("Content-Type", "application/json; charset=UTF-8");
+                //params.put("Authorization", "Token " + getStoredToken());
+                return params;
+            }
+        };
+
+        mQueue.add(req);
+        return (true);
+
+    }
+
+}

app/src/main/java/uk/org/openseizuredetector/SdAlgNn.java

@@ -32,6 +32,7 @@ public class SdAlgNn {
     private String mUrlBase = "https://osdApi.ddns.net";
     private InterpreterApi interpreter;
     private Context mContext;
+    private MlModelManager mMm;
     RequestQueue mQueue;
 
     private double mSdThresh;  // Acceleration Standard Deviation Threshold required to activate analysis (%)
@@ -42,6 +43,7 @@ public class SdAlgNn {
     public SdAlgNn(Context context) {
         Log.d(TAG, "SdAlgNn Constructor");
         mContext = context;
+        mMm = new MlModelManager(mContext);
 
         SharedPreferences SP = PreferenceManager
                 .getDefaultSharedPreferences(mContext);