Fixed #603 -- Added template debugging errors to pretty error-page output, if TEMPLATE_DEBUG setting is True. Also refactored FilterParser for a significant speed increase and changed the template_loader interface so that it returns information about the loader. Taken from new-admin. Thanks rjwittams and crew

git-svn-id: http://code.djangoproject.com/svn/django/trunk@1379 bcc190cf-cafb-0310-a4f2-bffc1f526a37

1 files changed, 95 insertions, 30 deletions

diff --git a/django/views/debug.py b/django/views/debug.py
index 189b244af2..012d7f9a75 100644
--- a/django/views/debug.py
+++ b/django/views/debug.py
@@ -1,19 +1,64 @@
-import re
-import os
-import sys
-import inspect
 from django.conf import settings
-from os.path import dirname, join as pathjoin
 from django.core.template import Template, Context
+from django.utils.html import escape
 from django.utils.httpwrappers import HttpResponseServerError, HttpResponseNotFound
+import inspect, os, re, sys
+from itertools import count, izip
+from os.path import dirname, join as pathjoin
 
 HIDDEN_SETTINGS = re.compile('SECRET|PASSWORD')
 
+def linebreak_iter(template_source):
+    newline_re = re.compile("^", re.M)
+    for match in newline_re.finditer(template_source):
+        yield match.start()
+    yield len(template_source) + 1
+
+def get_template_exception_info(exc_type, exc_value, tb):
+    origin, (start, end) = exc_value.source
+    template_source = origin.reload()
+    context_lines = 10
+    line = 0
+    upto = 0
+    source_lines = []
+    linebreaks = izip(count(0), linebreak_iter(template_source))
+    linebreaks.next() # skip the nothing before initial line start
+    for num, next in linebreaks:
+        if start >= upto and end <= next:
+            line = num
+            before = escape(template_source[upto:start])
+            during = escape(template_source[start:end])
+            after = escape(template_source[end:next - 1])
+        source_lines.append( (num, escape(template_source[upto:next - 1])) )
+        upto = next
+    total = len(source_lines)
+
+    top = max(0, line - context_lines)
+    bottom = min(total, line + 1 + context_lines)
+
+    template_info = {
+        'message': exc_value.args[0],
+        'source_lines': source_lines[top:bottom],
+        'before': before,
+        'during': during,
+        'after': after,
+        'top': top ,
+        'bottom': bottom ,
+        'total': total,
+        'line': line,
+        'name': origin.name,
+    }
+    exc_info = hasattr(exc_value, 'exc_info') and exc_value.exc_info or (exc_type, exc_value, tb)
+    return exc_info + (template_info,)
+
 def technical_500_response(request, exc_type, exc_value, tb):
     """
     Create a technical server error response.  The last three arguments are
     the values returned from sys.exc_info() and friends.
     """
+    template_info = None
+    if settings.TEMPLATE_DEBUG and hasattr(exc_value, 'source'):
+        exc_type, exc_value, tb, template_info = get_template_exception_info(exc_type, exc_value, tb)
     frames = []
     while tb is not None:
         filename = tb.tb_frame.f_code.co_filename
@@ -21,16 +66,16 @@ def technical_500_response(request, exc_type, exc_value, tb):
         lineno = tb.tb_lineno - 1
         pre_context_lineno, pre_context, context_line, post_context = _get_lines_from_file(filename, lineno, 7)
         frames.append({
-            'tb' : tb,
-            'filename' : filename,
-            'function' : function,
-            'lineno' : lineno,
-            'vars' : tb.tb_frame.f_locals.items(),
-            'id' : id(tb),
-            'pre_context' : pre_context,
-            'context_line' : context_line,
-            'post_context' : post_context,
-            'pre_context_lineno' : pre_context_lineno,
+            'tb': tb,
+            'filename': filename,
+            'function': function,
+            'lineno': lineno,
+            'vars': tb.tb_frame.f_locals.items(),
+            'id': id(tb),
+            'pre_context': pre_context,
+            'context_line': context_line,
+            'post_context': post_context,
+            'pre_context_lineno': pre_context_lineno,
         })
         tb = tb.tb_next
 
@@ -46,14 +91,14 @@ def technical_500_response(request, exc_type, exc_value, tb):
 
     t = Template(TECHNICAL_500_TEMPLATE)
     c = Context({
-        'exception_type' : exc_type.__name__,
-        'exception_value' : exc_value,
-        'frames' : frames,
-        'lastframe' : frames[-1],
-        'request' : request,
-        'request_protocol' : os.environ.get("HTTPS") == "on" and "https" or "http",
-        'settings' : settings_dict,
-
+        'exception_type': exc_type.__name__,
+        'exception_value': exc_value,
+        'frames': frames,
+        'lastframe': frames[-1],
+        'request': request,
+        'request_protocol': os.environ.get("HTTPS") == "on" and "https" or "http",
+        'settings': settings_dict,
+        'template_info': template_info,
     })
     return HttpResponseServerError(t.render(c), mimetype='text/html')
 
@@ -69,12 +114,12 @@ def technical_404_response(request, exception):
 
     t = Template(TECHNICAL_404_TEMPLATE)
     c = Context({
-        'root_urlconf' : settings.ROOT_URLCONF,
-        'urlpatterns' : tried,
-        'reason' : str(exception),
-        'request' : request,
-        'request_protocol' : os.environ.get("HTTPS") == "on" and "https" or "http",
-        'settings' : dict([(k, getattr(settings, k)) for k in dir(settings) if k.isupper()]),
+        'root_urlconf': settings.ROOT_URLCONF,
+        'urlpatterns': tried,
+        'reason': str(exception),
+        'request': request,
+        'request_protocol': os.environ.get("HTTPS") == "on" and "https" or "http",
+        'settings': dict([(k, getattr(settings, k)) for k in dir(settings) if k.isupper()]),
     })
     return HttpResponseNotFound(t.render(c), mimetype='text/html')
 
@@ -144,6 +189,9 @@ TECHNICAL_500_TEMPLATE = """
     #summary table { border:none; background:transparent; }
     #requestinfo h2, #requestinfo h3 { position:relative; margin-left:-100px; }
     #requestinfo h3 { margin-bottom:-1em; }
+    table.source td { font-family: monospace; white-space: pre; }
+    span.specific { background:#ffcab7; }
+    .error { background: #ffc; }
   </style>
   <script type="text/javascript">
   //<!--
@@ -221,7 +269,24 @@ TECHNICAL_500_TEMPLATE = """
     </tr>
   </table>
 </div>
-
+{% if template_info %}
+<div id="template">
+   <h2>Template</h2>
+   In template {{ template_info.name }}, error at line {{ template_info.line }}
+   <div>{{ template_info.message|escape }}</div>
+   <table class="source{% if template_info.top %} cut-top{% endif %}{% ifnotequal template_info.bottom template_info.total %} cut-bottom{% endifnotequal %}">
+   {% for source_line in template_info.source_lines %}
+   {% ifequal source_line.0 template_info.line %}
+       <tr class="error"><td>{{ source_line.0 }}</td>
+       <td>{{ template_info.before }}<span class="specific">{{ template_info.during }}</span>{{ template_info.after }}</td></tr>
+   {% else %}
+      <tr><td>{{ source_line.0 }}</td>
+      <td> {{ source_line.1 }}</td></tr>
+   {% endifequal %}
+   {% endfor %}
+   </table>
+</div>
+{% endif %}
 <div id="traceback">
   <h2>Traceback <span>(innermost last)</span></h2>
   <ul class="traceback">