Code now retries to send a request when there was a wrong response code (mostly 429, which is request limit reached). If there was another error, there will only be one retry

export/src/export/Main.java

@@ -34,6 +34,8 @@ public class Main
 {
 	public static final String baseUrl = "https://www.strava.com/api/v3/";
 	public static final String tokenUrl = "https://www.strava.com/api/v3/oauth/token";
+	private static final int retryTimes = 20;
+	private static final int httpCodeLimitReached = 429;
 	private static int athleteId = 0;
 	private static JSONParser parser = new JSONParser();
 	private static String testRequest;
@@ -95,6 +97,10 @@ public class Main
 
 		// get general information
 		JSONObject athleteInfo = saveGeneralInformation(token);
+		if(athleteInfo==null)	//error getting General Information
+		{
+			athleteInfo = new JSONObject();
+		}
 		athleteInfo.put("activities", allActivities);
 
 		try
@@ -127,9 +133,10 @@ public class Main
 		String requestUrlExtension = "activities/" + id + "/streams?"
 				+ "keys=[time,distance,latlng,altitude,velocity_smooth,heartrate,"
 				+ "cadence,watts,temp,moving,grade_smooth]&key_by_type=true";
-		String json = makeOneGetRequest(requestUrlExtension, token);
 		
-		if (json.isEmpty()||json.isBlank()||json.equals(""))
+		String json = makeGetRequestWithRetry(requestUrlExtension, token);;
+
+		if (json==null ||json.isEmpty()||json.isBlank()||json.equals(""))
 		{
 			return data;
 		}
@@ -179,9 +186,9 @@ public class Main
 		int pageIndex = 1;
 		while (true)
 		{							 
-			String requestExtension = "athlete/activities?page=" + pageIndex;
-			String json = makeOneGetRequest(requestExtension, token);
-			if (json.isEmpty() || json.isBlank() || json.equals("") || json.equals("[]")) // don't know where the last page is...
+			String requestExtension = "athlete/activities?per_page=500&page=" + pageIndex;
+			String json = makeGetRequestWithRetry(requestExtension, token);
+			if (json==null || json.isEmpty() || json.isBlank() || json.equals("") || json.equals("[]")) // don't know where the last page is...
 			{
 				break;
 			}
@@ -217,6 +224,53 @@ public class Main
 		return result;
 	}
 
+	/**
+	 * Method is used to find the next request window: It tries the same request again after 5 minutes.
+	 * After a set number of times (retryTimes) it stops if it still wasn't successful.
+	 * @param urlExtension UrlExtension for the request
+	 * @param token Token for the request
+	 * @return Data as a String or  {@code null} if there is no data
+	 */
+	static String makeGetRequestWithRetry(String urlExtension, String token)
+	{
+		String json=null;
+		int count=0;
+		do
+		{
+			try
+			{
+				json = makeOneGetRequest(urlExtension, token);
+			}
+			catch (ResponseCodeWrongException e)
+			{
+				//tried enough times, so stop now
+				if(count >= retryTimes)
+				{
+					return null;
+				}
+				//request limit is reached, try again later
+				if (e.getResponseCode()==httpCodeLimitReached)
+				{
+					count++;					
+				}
+				else //some other error: try only one other time!
+				{
+					count=retryTimes;
+				}
+				//Sleep for 5 minutes and try to get the next 15 min request window
+				try
+				{
+					TimeUnit.MINUTES.sleep(5);
+				}
+				catch (InterruptedException e1)
+				{
+				}
+			}
+			
+		}while(json==null);
+		return json;
+	}
+	
 	/**
 	 * Extracts an athletes general information.
 	 * 
@@ -232,7 +286,8 @@ public class Main
 		String meas_pref = "measurement_preference"; // Possible values = feet, meters
 		String weight = "weight";
 
-		String json = makeOneGetRequest("athlete", token);
+		
+		String json = makeGetRequestWithRetry("athlete", token);
 
 		JSONObject toSave = new JSONObject();
 		try
@@ -291,8 +346,9 @@ public class Main
 	 * @param token               Identification / authorization token of the
 	 *                            athlete
 	 * @return The response as a String, an empty String in case of error.
+	 * @throws ResponseCodeWrongException If there was an http error
 	 */
-	static String makeOneGetRequest(String requestUrlExtension, String token)
+	static String makeOneGetRequest(String requestUrlExtension, String token) throws ResponseCodeWrongException
 	{
 		if (testRequest != null)
 		{
@@ -335,20 +391,21 @@ public class Main
 	 * 
 	 * @param connection Connection to the site
 	 * @return Response as a String
-	 * @throws IOException in case of error
+	 * @throws IOException in case of error with the stream
+	 * @throws ResponseCodeWrongException if no data was read because of http problems
 	 */
-	static String getResponse(HttpsURLConnection connection) throws IOException
+	static String getResponse(HttpsURLConnection connection) throws IOException, ResponseCodeWrongException
 	{
 		StringBuilder result = new StringBuilder();
 		int responseCode = connection.getResponseCode();
 		if (responseCode != HttpURLConnection.HTTP_OK)
 		{
-			//excluded error messages appearing on missing streams
-			if(responseCode != HttpURLConnection.HTTP_NOT_FOUND)
+			//excluded error messages appearing on missing streams and reached rate limit
+			if(responseCode != HttpURLConnection.HTTP_NOT_FOUND && responseCode!= httpCodeLimitReached)
 			{
 				writeError("Wrong response code: " + responseCode);				
 			}
-			return "";
+			throw new ResponseCodeWrongException(responseCode);
 		}
 
 		try (Reader reader = new BufferedReader(
@@ -372,8 +429,9 @@ public class Main
 	 * @param data Triplet containing: a the client_id, b the client_secret, c the
 	 *             refresh_token
 	 * @return The response as a String, an empty String in case of error.
+	 * @throws ResponseCodeWrongException If there was an http error
 	 */
-	static String makeOnePostRequest(Triplet data)
+	static String makeOnePostRequest(Triplet data) throws ResponseCodeWrongException
 	{
 		HttpsURLConnection connection = null;
 		try
@@ -423,7 +481,41 @@ public class Main
 	 */
 	static Tuple getAccessToken(Triplet refreshInfo)
 	{
-		String json = makeOnePostRequest(refreshInfo);
+		String json=null;
+		int count =0;
+		do
+		{
+			try
+			{
+				json = makeOnePostRequest(refreshInfo);
+			}
+			catch (ResponseCodeWrongException e)
+			{
+				//tried enough times, so stop now
+				if(count >= retryTimes)
+				{
+					return null;
+				}
+				//request limit is reached, try again later
+				if (e.getResponseCode()==httpCodeLimitReached)
+				{
+					count++;					
+				}
+				else //some other error: try only one other time!
+				{
+					count=retryTimes;
+				}
+				//Sleep for 5 minutes and try to get the next 15 min request window
+				try
+				{
+					TimeUnit.MINUTES.sleep(5);
+				}
+				catch (InterruptedException e1)
+				{
+				}
+			}
+			
+		}while(json==null);
 		try
 		{
 			Object obj = parser.parse(json);
@@ -476,41 +568,3 @@ public class Main
 		}
 	}
 }
-
-class Tuple
-{
-	private String a;
-	private String b;
-
-	public Tuple(String a, String b)
-	{
-		this.a = a;
-		this.b = b;
-	}
-
-	public String getA()
-	{
-		return a;
-	}
-
-	public String getB()
-	{
-		return b;
-	}
-}
-
-class Triplet extends Tuple
-{
-	private String c;
-
-	public Triplet(String a, String b, String c)
-	{
-		super(a, b);
-		this.c = c;
-	}
-
-	public String getC()
-	{
-		return c;
-	}
-}

export/src/export/ResponseCodeWrongException.java

@@ -0,0 +1,24 @@
+package export;
+
+public class ResponseCodeWrongException extends Exception
+{
+	private static final long serialVersionUID = -1593242809354614946L;
+	private int responseCode;
+	
+	public ResponseCodeWrongException(int responseCode)
+	{
+		this.responseCode=responseCode;
+	}
+
+	public int getResponseCode()
+	{
+		return responseCode;
+	}
+
+	public void setResponseCode(int responseCode)
+	{
+		this.responseCode = responseCode;
+	}
+	
+	
+}

export/src/export/Triplet.java

@@ -0,0 +1,17 @@
+package export;
+
+public class Triplet extends Tuple
+{
+	private String c;
+
+	public Triplet(String a, String b, String c)
+	{
+		super(a, b);
+		this.c = c;
+	}
+
+	public String getC()
+	{
+		return c;
+	}
+}

export/src/export/Tuple.java

@@ -0,0 +1,23 @@
+package export;
+
+public class Tuple
+{
+	private String a;
+	private String b;
+
+	public Tuple(String a, String b)
+	{
+		this.a = a;
+		this.b = b;
+	}
+
+	public String getA()
+	{
+		return a;
+	}
+
+	public String getB()
+	{
+		return b;
+	}
+}