1 files changed, 149 insertions, 0 deletions
diff --git a/paste/debug/prints.py b/paste/debug/prints.py
new file mode 100644
index 0000000..b660bfa
--- /dev/null
+++ b/paste/debug/prints.py
@@ -0,0 +1,149 @@
+# (c) 2005 Ian Bicking and contributors; written for Paste (http://pythonpaste.org)
+# Licensed under the MIT license: http://www.opensource.org/licenses/mit-license.php
+"""
+Middleware that displays everything that is printed inline in
+application pages.
+
+Anything printed during the request will get captured and included on
+the page.  It will usually be included as a floating element in the
+top right hand corner of the page.  If you want to override this
+you can include a tag in your template where it will be placed::
+
+  <pre id="paste-debug-prints"></pre>
+
+You might want to include ``style="white-space: normal"``, as all the
+whitespace will be quoted, and this allows the text to wrap if
+necessary.
+
+"""
+
+from cStringIO import StringIO
+import re
+import cgi
+from paste.util import threadedprint
+from paste import wsgilib
+from paste import response
+import six
+import sys
+
+_threadedprint_installed = False
+
+__all__ = ['PrintDebugMiddleware']
+
+class TeeFile(object):
+
+    def __init__(self, files):
+        self.files = files
+
+    def write(self, v):
+        if isinstance(v, unicode):
+            # WSGI is picky in this case
+            v = str(v)
+        for file in self.files:
+            file.write(v)
+
+class PrintDebugMiddleware(object):
+
+    """
+    This middleware captures all the printed statements, and inlines
+    them in HTML pages, so that you can see all the (debug-intended)
+    print statements in the page itself.
+
+    There are two keys added to the environment to control this:
+    ``environ['paste.printdebug_listeners']`` is a list of functions
+    that will be called everytime something is printed.
+
+    ``environ['paste.remove_printdebug']`` is a function that, if
+    called, will disable printing of output for that request.
+
+    If you have ``replace_stdout=True`` then stdout is replaced, not
+    captured.
+    """
+
+    log_template = (
+        '<pre style="width: 40%%; border: 2px solid #000; white-space: normal; '
+        'background-color: #ffd; color: #000; float: right;">'
+        '<b style="border-bottom: 1px solid #000">Log messages</b><br>'
+        '%s</pre>')
+
+    def __init__(self, app, global_conf=None, force_content_type=False,
+                 print_wsgi_errors=True, replace_stdout=False):
+        # @@: global_conf should be handled separately and only for
+        # the entry point
+        self.app = app
+        self.force_content_type = force_content_type
+        if isinstance(print_wsgi_errors, six.string_types):
+            from paste.deploy.converters import asbool
+            print_wsgi_errors = asbool(print_wsgi_errors)
+        self.print_wsgi_errors = print_wsgi_errors
+        self.replace_stdout = replace_stdout
+        self._threaded_print_stdout = None
+
+    def __call__(self, environ, start_response):
+        global _threadedprint_installed
+        if environ.get('paste.testing'):
+            # In a testing environment this interception isn't
+            # useful:
+            return self.app(environ, start_response)
+        if (not _threadedprint_installed
+            or self._threaded_print_stdout is not sys.stdout):
+            # @@: Not strictly threadsafe
+            _threadedprint_installed = True
+            threadedprint.install(leave_stdout=not self.replace_stdout)
+            self._threaded_print_stdout = sys.stdout
+        removed = []
+        def remove_printdebug():
+            removed.append(None)
+        environ['paste.remove_printdebug'] = remove_printdebug
+        logged = StringIO()
+        listeners = [logged]
+        environ['paste.printdebug_listeners'] = listeners
+        if self.print_wsgi_errors:
+            listeners.append(environ['wsgi.errors'])
+        replacement_stdout = TeeFile(listeners)
+        threadedprint.register(replacement_stdout)
+        try:
+            status, headers, body = wsgilib.intercept_output(
+                environ, self.app)
+            if status is None:
+                # Some error occurred
+                status = '500 Server Error'
+                headers = [('Content-type', 'text/html')]
+                start_response(status, headers)
+                if not body:
+                    body = 'An error occurred'
+            content_type = response.header_value(headers, 'content-type')
+            if (removed or
+                (not self.force_content_type and
+                 (not content_type
+                  or not content_type.startswith('text/html')))):
+                if replacement_stdout == logged:
+                    # Then the prints will be lost, unless...
+                    environ['wsgi.errors'].write(logged.getvalue())
+                start_response(status, headers)
+                return [body]
+            response.remove_header(headers, 'content-length')
+            body = self.add_log(body, logged.getvalue())
+            start_response(status, headers)
+            return [body]
+        finally:
+            threadedprint.deregister()
+
+    _body_re = re.compile(r'<body[^>]*>', re.I)
+    _explicit_re = re.compile(r'<pre\s*[^>]*id="paste-debug-prints".*?>',
+                              re.I+re.S)
+
+    def add_log(self, html, log):
+        if not log:
+            return html
+        text = cgi.escape(log)
+        text = text.replace('\n', '<br>')
+        text = text.replace('  ', '&nbsp; ')
+        match = self._explicit_re.search(html)
+        if not match:
+            text = self.log_template % text
+            match = self._body_re.search(html)
+        if not match:
+            return text + html
+        else:
+            return html[:match.end()] + text + html[match.end():]