renamed CrawlDebug downloader middleware to DebugMiddleware

docs/ref/downloader-middleware.rst

@@ -18,10 +18,24 @@ DefaultHeadersMiddleware
 .. module:: scrapy.contrib.downloadermiddleware.defaultheaders
    :synopsis: Default Headers Downloader Middleware
 
-.. class:: scrapy.contrib.downloadermiddleware.defaultheaders.DefaultHeadersMiddleware
+.. class:: DefaultHeadersMiddleware
 
-This middleware sets all default requests headers specified in the
-:setting:`DEFAULT_REQUEST_HEADERS` setting.
+    This middleware sets all default requests headers specified in the
+    :setting:`DEFAULT_REQUEST_HEADERS` setting.
+
+DebugMiddleware
+---------------
+
+.. module:: scrapy.contrib.downloadermiddleware.debug
+   :synopsis: Downloader middlewares for debugging
+
+.. class:: DebugMiddleware
+
+    This is a convenient middleware to inspect what's passing through the
+    downloader middleware. It logs all requests and responses catched by the
+    middleware component methods. This middleware does not use any settings and
+    does not come enabled by default. Instead, it's meant to be inserted at the
+    point of the middleware that you want to inspect.
 
 HttpCacheMiddleware
 -------------------

docs/ref/settings.rst

@@ -333,7 +333,6 @@ Default::
         'scrapy.contrib.downloadermiddleware.redirect.RedirectMiddleware': 600,
         'scrapy.contrib.downloadermiddleware.cookies.CookiesMiddleware': 700,
         'scrapy.contrib.downloadermiddleware.httpcompression.HttpCompressionMiddleware': 800,
-        'scrapy.contrib.downloadermiddleware.debug.CrawlDebug': 840,
         'scrapy.contrib.downloadermiddleware.stats.DownloaderStats': 850,
         'scrapy.contrib.downloadermiddleware.httpcache.HttpCacheMiddleware': 900,
     }

scrapy/conf/default_settings.py

@@ -72,7 +72,6 @@ DOWNLOADER_MIDDLEWARES_BASE = {
     'scrapy.contrib.downloadermiddleware.redirect.RedirectMiddleware': 600,
     'scrapy.contrib.downloadermiddleware.cookies.CookiesMiddleware': 700,
     'scrapy.contrib.downloadermiddleware.httpcompression.HttpCompressionMiddleware': 800,
-    'scrapy.contrib.downloadermiddleware.debug.CrawlDebug': 840,
     'scrapy.contrib.downloadermiddleware.stats.DownloaderStats': 850,
     'scrapy.contrib.downloadermiddleware.cache.HttpCacheMiddleware': 900,
     # Downloader side

scrapy/contrib/downloadermiddleware/debug.py

@@ -1,18 +1,24 @@
 from scrapy import log
 from scrapy.core.exceptions import NotConfigured
 
+class DebugMiddleware(object):
+
+    def process_request(self, request, spider):
+        log.msg("process_request %r" % request, domain=spider.domain_name, level=log.DEBUG)
+
+    def process_exception(self, request, exception, spider):
+        log.msg("process_exception %s in %r" % (exception, request), domain=spider.domain_name, level=log.DEBUG)
+
+    def process_response(self, request, response, spider):
+        log.msg("process_response %s from %r" % (response, request), domain=spider.domain_name, level=log.DEBUG)
+        return response
+
+# FIXME: backwards compatibility - will be removed before 0.7 release
+
+import warnings
+
 class CrawlDebug(object):
 
     def __init__(self):
-        raise NotConfigured
-    
-    def process_request(self, request, spider):
-        log.msg("Crawling %s" % repr(request), domain=spider.domain_name, level=log.DEBUG)
-
-    def process_exception(self, request, exception, spider):
-        log.msg("Crawl exception %s in %s" % (exception, repr(request)), domain=spider.domain_name, level=log.DEBUG)
-
-    def process_response(self, request, response, spider):
-        log.msg("Fetched %s from %s" % (response, repr(request)), domain=spider.domain_name, level=log.DEBUG)
-        return response
-
+        warnings.warn("scrapy.contrib.downloadermiddleware.debug.CrawlDebug has been replaced by scrapy.contrib.downloadermiddleware.debug.DebugDownloaderMiddleware")
+        DebugMiddleware.__init__(self)