static void Main(string[] args)
{
// Creating Needed Instances
RequestsHandler httpClient = new RequestsHandler();
AppStoreParser parser = new AppStoreParser();
// Loading Configuration
LogSetup.InitializeLog("Apple_Store_Categories_Worker.log", "info");
_logger = LogManager.GetCurrentClassLogger();
// Loading Config
_logger.Info("Loading Configurations from App.config");
LoadConfiguration();
// Control Variable (Bool - Should the process use proxies? )
bool shouldUseProxies = false;
// Checking for the need to use proxies
if (args != null && args.Length == 1)
{
// Setting flag to true
shouldUseProxies = true;
// Loading proxies from .txt received as argument
String fPath = args[0];
// Sanity Check
if (!File.Exists(fPath))
{
_logger.Fatal("Couldnt find proxies on path : " + fPath);
System.Environment.Exit(-100);
}
// Reading Proxies from File
string[] fLines = File.ReadAllLines(fPath, Encoding.GetEncoding("UTF-8"));
try
{
// Actual Load of Proxies
ProxiesLoader.Load(fLines.ToList());
}
catch (Exception ex)
{
_logger.Fatal(ex);
System.Environment.Exit(-101);
}
}
// AWS Queue Handler
_logger.Info("Initializing Queues");
AWSSQSHelper categoriesUrlQueue = new AWSSQSHelper(_categoriesQueueName, _maxMessagesPerDequeue, _awsKey, _awsKeySecret);
AWSSQSHelper charactersUrlQueue = new AWSSQSHelper(_characterUrlsQueueName, _maxMessagesPerDequeue, _awsKey, _awsKeySecret);
// Setting Error Flag to No Error ( 0 )
System.Environment.ExitCode = 0;
// Initialiazing Control Variables
int fallbackWaitTime = 1;
_logger.Info("Started Processing Category Urls");
do
{
try
{
// Dequeueing messages from the Queue
if (!categoriesUrlQueue.DeQueueMessages())
{
Thread.Sleep(_hiccupTime); // Hiccup
continue;
}
// Checking for no message received, and false positives situations
if (!categoriesUrlQueue.AnyMessageReceived())
{
// If no message was found, increases the wait time
int waitTime;
if (fallbackWaitTime <= 12)
{
// Exponential increase on the wait time, truncated after 12 retries
waitTime = Convert.ToInt32(Math.Pow(2, fallbackWaitTime) * 1000);
}
else // Reseting Wait after 12 fallbacks
{
waitTime = 2000;
fallbackWaitTime = 0;
}
fallbackWaitTime++;
// Sleeping before next try
_logger.Info("Fallback (seconds) => " + waitTime);
Thread.Sleep(waitTime);
continue;
}
// Reseting fallback time
fallbackWaitTime = 1;
// Iterating over dequeued Messages
foreach (var categoryUrl in categoriesUrlQueue.GetDequeuedMessages())
{
// Console Feedback
_logger.Info("Started Parsing Category : " + categoryUrl.Body);
try
{
// Retries Counter
int retries = 0;
string htmlResponse;
// Retrying if necessary
do
{
// Executing Http Request for the Category Url
htmlResponse = httpClient.Get(categoryUrl.Body, shouldUseProxies);
if (String.IsNullOrEmpty(htmlResponse))
{
_logger.Error("Retrying Request for Category Page");
retries++;
}
} while (String.IsNullOrWhiteSpace(htmlResponse) && retries <= _maxRetries);
// Checking if retries failed
if (String.IsNullOrWhiteSpace(htmlResponse))
{
// Deletes Message and moves on
categoriesUrlQueue.DeleteMessage(categoryUrl);
continue;
}
// If the request worked, parses the urls out of the page
foreach (string characterUrls in parser.ParseCharacterUrls(htmlResponse))
{
// Enqueueing Urls
charactersUrlQueue.EnqueueMessage(HttpUtility.HtmlDecode(characterUrls));
}
}
catch (Exception ex)
{
_logger.Error(ex);
}
finally
{
// Deleting the message
categoriesUrlQueue.DeleteMessage(categoryUrl);
}
}
}
catch (Exception ex)
{
_logger.Error(ex);
}
} while (true);
}
static void Main(string[] args)
{
// Creating Needed Instances
RequestsHandler httpClient = new RequestsHandler();
AppStoreParser parser = new AppStoreParser();
_logger = new LogWrapper();
// Loading Configuration
_logger.LogMessage("Loading Configurations from App.config");
LoadConfiguration();
// AWS Queue Handler
_logger.LogMessage("Initializing Queues");
AWSSQSHelper categoriesUrlQueue = new AWSSQSHelper(_categoriesQueueName, _maxMessagesPerDequeue, _awsKey, _awsKeySecret);
AWSSQSHelper charactersUrlQueue = new AWSSQSHelper(_characterUrlsQueueName, _maxMessagesPerDequeue, _awsKey, _awsKeySecret);
// Setting Error Flag to No Error ( 0 )
System.Environment.ExitCode = 0;
// Initialiazing Control Variables
int fallbackWaitTime = 1;
_logger.LogMessage("Started Processing Category Urls");
do
{
try
{
// Dequeueing messages from the Queue
if (!categoriesUrlQueue.DeQueueMessages())
{
Thread.Sleep(_hiccupTime); // Hiccup
continue;
}
// Checking for no message received, and false positives situations
if (!categoriesUrlQueue.AnyMessageReceived())
{
// If no message was found, increases the wait time
int waitTime;
if (fallbackWaitTime <= 12)
{
// Exponential increase on the wait time, truncated after 12 retries
waitTime = Convert.ToInt32(Math.Pow(2, fallbackWaitTime) * 1000);
}
else // Reseting Wait after 12 fallbacks
{
waitTime = 2000;
fallbackWaitTime = 0;
}
fallbackWaitTime++;
// Sleeping before next try
Console.WriteLine("Fallback (seconds) => " + waitTime);
Thread.Sleep(waitTime);
continue;
}
// Reseting fallback time
fallbackWaitTime = 1;
// Iterating over dequeued Messages
foreach (var categoryUrl in categoriesUrlQueue.GetDequeuedMessages())
{
// Console Feedback
_logger.LogMessage("Started Parsing Category : " + categoryUrl.Body);
try
{
// Retries Counter
int retries = 0;
string htmlResponse;
// Retrying if necessary
do
{
// Executing Http Request for the Category Url
htmlResponse = httpClient.Get(categoryUrl.Body);
if (String.IsNullOrEmpty(htmlResponse))
{
_logger.LogMessage("Retrying Request for Category Page", "Request Error", BDC.BDCCommons.TLogEventLevel.Error);
retries++;
}
} while (String.IsNullOrWhiteSpace(htmlResponse) && retries <= _maxRetries);
// Checking if retries failed
if (String.IsNullOrWhiteSpace(htmlResponse))
{
// Deletes Message and moves on
categoriesUrlQueue.DeleteMessage(categoryUrl);
continue;
}
// If the request worked, parses the urls out of the page
foreach (string characterUrls in parser.ParseCharacterUrls(htmlResponse))
{
// Enqueueing Urls
charactersUrlQueue.EnqueueMessage(HttpUtility.HtmlDecode(characterUrls));
}
}
catch (Exception ex)
{
_logger.LogMessage(ex.Message, "Category Url Processing", BDC.BDCCommons.TLogEventLevel.Error);
}
finally
{
// Deleting the message
categoriesUrlQueue.DeleteMessage(categoryUrl);
}
}
}
catch (Exception ex)
{
_logger.LogMessage(ex);
}
} while (true);
}