small code cleanups
[invirt/packages/invirt-web.git] / code / main.py
index 620c0b9..8199250 100755 (executable)
@@ -6,7 +6,6 @@ import cPickle
 import cgi
 import datetime
 import hmac
-import os
 import sha
 import simplejson
 import sys
@@ -18,7 +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()
@@ -31,7 +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')
 
@@ -119,12 +117,6 @@ 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)
-    return templates.error(searchList=[d])
-
 def invalidInput(op, username, fields, err, emsg):
     """Print an error page when an InvalidInput exception occurs"""
     d = dict(op=op, user=username, err_field=err.err_field,
@@ -262,7 +254,7 @@ def vnc(username, state, fields):
              on=status,
              has_vnc=has_vnc,
              machine=machine,
-             hostname=os.environ.get('SERVER_NAME', 'localhost'),
+             hostname=state.environ.get('SERVER_NAME', 'localhost'),
              authtoken=token)
     return templates.vnc(searchList=[d])
 
@@ -340,7 +332,7 @@ def command(username, state, fields):
         return templates.list(searchList=[d])
     elif back == 'info':
         machine = validation.Validate(username, state, machine_id=fields.getfirst('machine_id')).machine
-        return ({'Status': '302',
+        return ({'Status': '303 See Other',
                  'Location': '/info?machine_id=%d' % machine.machine_id},
                 "You shouldn't see this message.")
     else:
@@ -378,7 +370,7 @@ def modifyDict(username, state, fields):
             machine.owner = validate.owner
             update_acl = True
         if hasattr(validate, 'name'):
-            machine.name = name
+            machine.name = validate.name
         if hasattr(validate, 'admin') and validate.admin != machine.administrator:
             machine.administrator = validate.admin
             update_acl = True
@@ -412,7 +404,7 @@ def modify(username, state, fields):
         machine = modify_dict['machine']
         result = 'Success!'
         err = None
-    info_dict = infoDict(username, machine)
+    info_dict = infoDict(username, state, machine)
     info_dict['err'] = err
     if err:
         for field in fields.keys():
@@ -472,11 +464,11 @@ console will suffer artifacts.
     return templates.help(searchList=[d])
 
 
-def badOperation(u, e):
+def badOperation(u, s, e):
     """Function called when accessing an unknown URI."""
     raise CodeError("Unknown operation")
 
-def infoDict(username, machine):
+def infoDict(username, state, machine):
     """Get the variables used by info.tmpl."""
     status = controls.statusInfo(machine)
     checkpoint.checkpoint('Getting status info')
@@ -572,7 +564,7 @@ def infoDict(username, machine):
 def info(username, state, fields):
     """Handler for info on a single VM."""
     machine = validation.Validate(username, state, machine_id=fields.getfirst('machine_id')).machine
-    d = infoDict(username, machine)
+    d = infoDict(username, state, machine)
     checkpoint.checkpoint('Got infodict')
     return templates.info(searchList=[d])
 
@@ -580,6 +572,10 @@ 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,
@@ -587,7 +583,8 @@ 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."""
@@ -595,6 +592,30 @@ 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 show_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 getUser(environ):
     """Return the current user based on the SSL environment variables"""
@@ -605,83 +626,84 @@ def getUser(environ):
         return None
     return email[:-8]
 
-def main(operation, username, state, fields):
-    start_time = time.time()
-    fun = mapping.get(operation, badOperation)
-
-    if fun not in (helpHandler, ):
-        connect('postgres://sipb-xen@sipb-xen-dev.mit.edu/sipb_xen')
-    try:
-        checkpoint.checkpoint('Before')
-        output = fun(username, state, fields)
-        checkpoint.checkpoint('After')
-
-        headers = dict(DEFAULT_HEADERS)
-        if isinstance(output, tuple):
-            new_headers, output = output
-            headers.update(new_headers)
-        e = revertStandardError()
-        if e:
-            if isinstance(output, basestring):
-                sys.stderr = StringIO()
-                x = str(output)
-                print >> sys.stderr, x
-                print >> sys.stderr, 'XXX'
-                print >> sys.stderr, e
-                raise Exception()
-            output.addError(e)
-        printHeaders(headers)
-        output_string =  str(output)
-        checkpoint.checkpoint('output as a string')
-        print output_string
+class App:
+    def __init__(self, environ, start_response):
+        self.environ = environ
+        self.start = start_response
+
+        self.username = getUser(environ)
+        self.state = State(self.username)
+        self.state.environ = environ
+
+    def __iter__(self):
+        sys.stderr = StringIO()
+        fields = cgi.FieldStorage(fp=self.environ['wsgi.input'], environ=self.environ)
+        operation = self.environ.get('PATH_INFO', '')
+        if not operation:
+            self.start("301 Moved Permanently", [('Location',
+                                                  self.environ['SCRIPT_NAME']+'/')])
+            return
+        if self.username is None:
+            operation = 'unauth'
+        if operation.startswith('/'):
+            operation = operation[1:]
+        if not operation:
+            operation = 'list'
+        print 'Starting', operation
+
+        start_time = time.time()
+        fun = mapping.get(operation, badOperation)
+        try:
+            checkpoint.checkpoint('Before')
+            output = fun(self.username, self.state, fields)
+            checkpoint.checkpoint('After')
+
+            headers = dict(DEFAULT_HEADERS)
+            if isinstance(output, tuple):
+                new_headers, output = output
+                headers.update(new_headers)
+            e = revertStandardError()
+            if e:
+                if isinstance(output, basestring):
+                    sys.stderr = StringIO()
+                    x = str(output)
+                    print >> sys.stderr, x
+                    print >> sys.stderr, 'XXX'
+                    print >> sys.stderr, e
+                    raise Exception()
+                output.addError(e)
+            output_string =  str(output)
+            checkpoint.checkpoint('output as a string')
+        except Exception, err:
+            if not fields.has_key('js'):
+                if isinstance(err, InvalidInput):
+                    self.start('200 OK', [('Content-Type', 'text/html')])
+                    e = revertStandardError()
+                    yield str(invalidInput(operation, self.username, fields,
+                                           err, e))
+                    return
+            import traceback
+            self.start('500 Internal Server Error',
+                       [('Content-Type', 'text/html')])
+            e = revertStandardError()
+            s = show_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())
+        yield output_string
         if fields.has_key('timedebug'):
-            print '<pre>%s</pre>' % cgi.escape(checkpoint)
-    except Exception, err:
-        if not fields.has_key('js'):
-            if isinstance(err, CodeError):
-                print 'Content-Type: text/html\n'
-                e = revertStandardError()
-                print error(operation, state.username, fields, err, e)
-                sys.exit(1)
-            if isinstance(err, InvalidInput):
-                print 'Content-Type: text/html\n'
-                e = revertStandardError()
-                print invalidInput(operation, state.username, fields, err, e)
-                sys.exit(1)
-        print 'Content-Type: text/plain\n'
-        print 'Uh-oh!  We experienced an error.'
-        print 'Please email xvm-dev@mit.edu with the contents of this page.'
-        print '----'
-        e = revertStandardError()
-        print e
-        print '----'
-        raise
+            yield '<pre>%s</pre>' % cgi.escape(str(checkpoint))
+
+def constructor():
+    connect('postgres://sipb-xen@sipb-xen-dev.mit.edu/sipb_xen')
+    return App
+
+def main():
+    from flup.server.fcgi_fork import WSGIServer
+    WSGIServer(constructor()).run()
 
 if __name__ == '__main__':
-    fields = cgi.FieldStorage()
-
-    if fields.has_key('sqldebug'):
-        import logging
-        logging.basicConfig()
-        logging.getLogger('sqlalchemy.engine').setLevel(logging.INFO)
-        logging.getLogger('sqlalchemy.orm.unitofwork').setLevel(logging.INFO)
-
-    username = getUser(os.environ)
-    state = State(username)
-    operation = os.environ.get('PATH_INFO', '')
-    if not operation:
-        print "Status: 301 Moved Permanently"
-        print 'Location: ' + os.environ['SCRIPT_NAME']+'/\n'
-        sys.exit(0)
-    if username is None:
-        operation = 'unauth'
-    if operation.startswith('/'):
-        operation = operation[1:]
-    if not operation:
-        operation = 'list'
-
-    if os.getenv("SIPB_XEN_PROFILE"):
-        import profile
-        profile.run('main(operation, username, state, fields)', 'log-'+operation)
-    else:
-        main(operation, username, state, fields)
+    main()