Removed parallel loop from download. Double checking the urls of the images

source/sites/basesite.d

@@ -16,7 +16,7 @@ protected:
     import std.array    : replace, split;
     import std.string   : indexOf;
     import std.net.curl : download;
-    import std.parallelism : parallel;
+    /* import std.parallelism : parallel; */
 
     Config _config;
 
@@ -59,8 +59,9 @@ protected:
     +/
     void downloadImages(string[] imageUrls, string outputPath)
     {
-        foreach(string url; parallel(imageUrls))
+        foreach(string url; imageUrls)
         {
+
             // Extract the filename from the url
             string filepath = outputPath ~ extractFileNameFromUrl(url);
 

source/sites/nhentai.d

@@ -23,7 +23,7 @@ class NHentai : BaseSite
     + This function tests if the jpg supplied in the url actually
     + exists on the server or if its a 404
     +/
-    bool isJPGValid(string url)
+    bool isUrlValid(string url)
     {
         try
         {
@@ -88,21 +88,32 @@ class NHentai : BaseSite
 
         // Loop over the range in parallel to make it faster
         auto range = new int[pageNumber];
-        foreach(i, ref element; parallel(range))
+        foreach(i, ref elment; parallel(range))
         {
             // Craft the url with all parameters
-            string extractedUrl = imageUrl ~ contentIDMatch ~ "/" ~ to!string(i) ~ ".jpg";
+            string extractedUrl = imageUrl ~ contentIDMatch ~ "/" ~ to!string(i+1);// ~ ".jpg";
 
-            if(_config.enable_debug_output) writefln("[i] Checking if %s is an actual jpg", extractedUrl);
-
-            // See if the url is a valid jpg and if not change the extension to png
-            if(!isJPGValid(extractedUrl))
+            if(isUrlValid(extractedUrl ~ ".jpg"))
             {
-                if(_config.enable_debug_output) writefln("[i] %s is not a valid jpg changing to png!!", extractedUrl);
-                extractedUrl = extractedUrl.replace(".jpg", ".png");
+                // The url with a jpg at the end didn't return a
+                // 404 so the image is assumed to be valid
+                extractedUrl ~= ".jpg";
+            }
+            else if(isUrlValid(extractedUrl ~ ".png"))
+            {
+                // The url with a jpg at the end didn't return a
+                // 404 so the image is assumed to be valid
+                extractedUrl ~= ".png";
+            }
+            else
+            {
+                // Both reqests failed so we are going to skip this image
+                writeln("[!] Failed to get image for url : ", extractedUrl);
+                continue;
             }
 
             // Add the url to the list
+            if(_config.enable_debug_output) writefln("[i] The image url %s is assumed to be valid", extractedUrl);
             urls ~= extractedUrl;
         }