one world, one error-reporting mechanism

[invirt/packages/invirt-web.git] / code / main.py

diff --git a/code/main.py b/code/main.py
index d05eaca..646f7d0 100755 (executable)
--- a/code/main.py
+++ b/code/main.py
@@ -17,7 +17,7 @@ def revertStandardError():
     """Move stderr to stdout, and return the contents of the old stderr."""
     errio = sys.stderr
     if not isinstance(errio, StringIO):
-        return None
+        return ''
     sys.stderr = sys.stdout
     errio.seek(0)
     return errio.read()
@@ -30,7 +30,6 @@ def printError():
 if __name__ == '__main__':
     import atexit
     atexit.register(printError)
-    sys.stderr = StringIO()
 
 sys.path.append('/home/ecprice/.local/lib/python2.5/site-packages')
 
@@ -118,10 +117,14 @@ class Defaults:
 
 DEFAULT_HEADERS = {'Content-Type': 'text/html'}
 
-def error(op, username, fields, err, emsg):
-    """Print an error page when a CodeError occurs"""
-    d = dict(op=op, user=username, errorMessage=str(err),
-             stderr=emsg)
+def error(op, username, fields, err, emsg, traceback):
+    """Print an error page when an exception occurs"""
+    d = dict(op=op, user=username, fields=fields,
+             errorMessage=str(err), stderr=emsg, traceback=traceback)
+    details = templates.error_raw(searchList=[d])
+    send_error_mail('xvm error on %s for %s: %s' % (op, username, err),
+                    details)
+    d['details'] = details
     return templates.error(searchList=[d])
 
 def invalidInput(op, username, fields, err, emsg):
@@ -579,6 +582,10 @@ def unauthFront(_, _2, fields):
     """Information for unauth'd users."""
     return templates.unauth(searchList=[{'simple' : True}])
 
+def throwError(_, __, ___):
+    """Throw an error, to test the error-tracing mechanisms."""
+    raise RuntimeError("test of the emergency broadcast system")
+
 mapping = dict(list=listVms,
                vnc=vnc,
                command=command,
@@ -586,7 +593,8 @@ mapping = dict(list=listVms,
                info=info,
                create=create,
                help=helpHandler,
-               unauth=unauthFront)
+               unauth=unauthFront,
+               errortest=throwError)
 
 def printHeaders(headers):
     """Print a dictionary as HTTP headers."""
@@ -594,6 +602,20 @@ def printHeaders(headers):
         print '%s: %s' % (key, value)
     print
 
+def send_error_mail(subject, body):
+    import subprocess
+
+    to = 'xvm@mit.edu'
+    mail = """To: %s
+From: root@xvm.mit.edu
+Subject: %s
+
+%s
+""" % (to, subject, body)
+    p = subprocess.Popen(['/usr/sbin/sendmail', to], stdin=subprocess.PIPE)
+    p.stdin.write(mail)
+    p.stdin.close()
+    p.wait()
 
 def getUser(environ):
     """Return the current user based on the SSL environment variables"""
@@ -614,8 +636,8 @@ class App:
         self.state.environ = environ
 
     def __iter__(self):
+        sys.stderr = StringIO()
         fields = cgi.FieldStorage(fp=self.environ['wsgi.input'], environ=self.environ)
-        print >> sys.stderr, fields
         operation = self.environ.get('PATH_INFO', '')
         if not operation:
             self.start("301 Moved Permanently", [('Location',
@@ -655,26 +677,19 @@ class App:
             checkpoint.checkpoint('output as a string')
         except Exception, err:
             if not fields.has_key('js'):
-                if isinstance(err, CodeError):
-                    self.start('500 Internal Server Error', [('Content-Type', 'text/html')])
-                    e = revertStandardError()
-                    s = error(operation, self.username, fields, err, e)
-                    yield str(s)
-                    return
                 if isinstance(err, InvalidInput):
                     self.start('200 OK', [('Content-Type', 'text/html')])
                     e = revertStandardError()
                     yield str(invalidInput(operation, self.username, fields, err, e))
                     return
-            self.start('500 Internal Server Error', [('Content-Type', 'text/plain')])
             import traceback
-            yield '''Uh-oh!  We experienced an error.'
-Please email xvm-dev@mit.edu with the contents of this page.'
-----
-%s
-----
-%s
-----''' % (str(err), traceback.format_exc())
+            self.start('500 Internal Server Error',
+                       [('Content-Type', 'text/html')])
+            e = revertStandardError()
+            s = error(operation, self.username, fields,
+                           err, e, traceback.format_exc())
+            yield str(s)
+            return
         status = headers.setdefault('Status', '200 OK')
         del headers['Status']
         self.start(status, headers.items())