8 files changed, 950 insertions, 0 deletions
diff --git a/scripts/app_engine_server/gae_shell/README b/scripts/app_engine_server/gae_shell/README
new file mode 100644
index 0000000..5b0089f
--- /dev/null
+++ b/scripts/app_engine_server/gae_shell/README
@@ -0,0 +1,17 @@
+An interactive, stateful AJAX shell that runs Python code on the server.
+
+Part of http://code.google.com/p/google-app-engine-samples/.
+
+May be run as a standalone app or in an existing app as an admin-only handler.
+Can be used for system administration tasks, as an interactive way to try out
+APIs, or as a debugging aid during development.
+
+The logging, os, sys, db, and users modules are imported automatically.
+
+Interpreter state is stored in the datastore so that variables, function
+definitions, and other values in the global and local namespaces can be used
+across commands.
+
+To use the shell in your app, copy shell.py, static/*, and templates/* into
+your app's source directory. Then, copy the URL handlers from app.yaml into
+your app.yaml.
diff --git a/scripts/app_engine_server/gae_shell/__init__.py b/scripts/app_engine_server/gae_shell/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/scripts/app_engine_server/gae_shell/__init__.py
diff --git a/scripts/app_engine_server/gae_shell/__init__.pyc b/scripts/app_engine_server/gae_shell/__init__.pyc
new file mode 100644
index 0000000..84951e9
--- /dev/null
+++ b/scripts/app_engine_server/gae_shell/__init__.pyc
diff --git a/scripts/app_engine_server/gae_shell/shell.py b/scripts/app_engine_server/gae_shell/shell.py
new file mode 100755
index 0000000..df2fb17
--- /dev/null
+++ b/scripts/app_engine_server/gae_shell/shell.py
@@ -0,0 +1,308 @@
+#!/usr/bin/python
+#
+# Copyright 2007 Google Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+An interactive, stateful AJAX shell that runs Python code on the server.
+
+Part of http://code.google.com/p/google-app-engine-samples/.
+
+May be run as a standalone app or in an existing app as an admin-only handler.
+Can be used for system administration tasks, as an interactive way to try out
+APIs, or as a debugging aid during development.
+
+The logging, os, sys, db, and users modules are imported automatically.
+
+Interpreter state is stored in the datastore so that variables, function
+definitions, and other values in the global and local namespaces can be used
+across commands.
+
+To use the shell in your app, copy shell.py, static/*, and templates/* into
+your app's source directory. Then, copy the URL handlers from app.yaml into
+your app.yaml.
+
+TODO: unit tests!
+"""
+
+import logging
+import new
+import os
+import pickle
+import sys
+import traceback
+import types
+import wsgiref.handlers
+
+from google.appengine.api import users
+from google.appengine.ext import db
+from google.appengine.ext import webapp
+from google.appengine.ext.webapp import template
+
+
+# Set to True if stack traces should be shown in the browser, etc.
+_DEBUG = True
+
+# The entity kind for shell sessions. Feel free to rename to suit your app.
+_SESSION_KIND = '_Shell_Session'
+
+# Types that can't be pickled.
+UNPICKLABLE_TYPES = (
+  types.ModuleType,
+  types.TypeType,
+  types.ClassType,
+  types.FunctionType,
+  )
+
+# Unpicklable statements to seed new sessions with.
+INITIAL_UNPICKLABLES = [
+  'import logging',
+  'import os',
+  'import sys',
+  'from google.appengine.ext import db',
+  'from google.appengine.api import users',
+  ]
+
+
+class Session(db.Model):
+  """A shell session. Stores the session's globals.
+
+  Each session globals is stored in one of two places:
+
+  If the global is picklable, it's stored in the parallel globals and
+  global_names list properties. (They're parallel lists to work around the
+  unfortunate fact that the datastore can't store dictionaries natively.)
+
+  If the global is not picklable (e.g. modules, classes, and functions), or if
+  it was created by the same statement that created an unpicklable global,
+  it's not stored directly. Instead, the statement is stored in the
+  unpicklables list property. On each request, before executing the current
+  statement, the unpicklable statements are evaluated to recreate the
+  unpicklable globals.
+
+  The unpicklable_names property stores all of the names of globals that were
+  added by unpicklable statements. When we pickle and store the globals after
+  executing a statement, we skip the ones in unpicklable_names.
+
+  Using Text instead of string is an optimization. We don't query on any of
+  these properties, so they don't need to be indexed.
+  """
+  global_names = db.ListProperty(db.Text)
+  globals = db.ListProperty(db.Blob)
+  unpicklable_names = db.ListProperty(db.Text)
+  unpicklables = db.ListProperty(db.Text)
+
+  def set_global(self, name, value):
+    """Adds a global, or updates it if it already exists.
+
+    Also removes the global from the list of unpicklable names.
+
+    Args:
+      name: the name of the global to remove
+      value: any picklable value
+    """
+    blob = db.Blob(pickle.dumps(value))
+
+    if name in self.global_names:
+      index = self.global_names.index(name)
+      self.globals[index] = blob
+    else:
+      self.global_names.append(db.Text(name))
+      self.globals.append(blob)
+
+    self.remove_unpicklable_name(name)
+
+  def remove_global(self, name):
+    """Removes a global, if it exists.
+
+    Args:
+      name: string, the name of the global to remove
+    """
+    if name in self.global_names:
+      index = self.global_names.index(name)
+      del self.global_names[index]
+      del self.globals[index]
+
+  def globals_dict(self):
+    """Returns a dictionary view of the globals.
+    """
+    return dict((name, pickle.loads(val))
+                for name, val in zip(self.global_names, self.globals))
+
+  def add_unpicklable(self, statement, names):
+    """Adds a statement and list of names to the unpicklables.
+
+    Also removes the names from the globals.
+
+    Args:
+      statement: string, the statement that created new unpicklable global(s).
+      names: list of strings; the names of the globals created by the statement.
+    """
+    self.unpicklables.append(db.Text(statement))
+
+    for name in names:
+      self.remove_global(name)
+      if name not in self.unpicklable_names:
+        self.unpicklable_names.append(db.Text(name))
+
+  def remove_unpicklable_name(self, name):
+    """Removes a name from the list of unpicklable names, if it exists.
+
+    Args:
+      name: string, the name of the unpicklable global to remove
+    """
+    if name in self.unpicklable_names:
+      self.unpicklable_names.remove(name)
+
+
+class FrontPageHandler(webapp.RequestHandler):
+  """Creates a new session and renders the shell.html template.
+  """
+
+  def get(self):
+    # set up the session. TODO: garbage collect old shell sessions
+    session_key = self.request.get('session')
+    if session_key:
+      session = Session.get(session_key)
+    else:
+      # create a new session
+      session = Session()
+      session.unpicklables = [db.Text(line) for line in INITIAL_UNPICKLABLES]
+      session_key = session.put()
+
+    template_file = os.path.join(os.path.dirname(__file__), 'templates',
+                                 'shell.html')
+    session_url = '/?session=%s' % session_key
+    vars = { 'server_software': os.environ['SERVER_SOFTWARE'],
+             'python_version': sys.version,
+             'session': str(session_key),
+             'user': users.get_current_user(),
+             'login_url': users.create_login_url(session_url),
+             'logout_url': users.create_logout_url(session_url),
+             }
+    rendered = webapp.template.render(template_file, vars, debug=_DEBUG)
+    self.response.out.write(rendered)
+
+
+class StatementHandler(webapp.RequestHandler):
+  """Evaluates a python statement in a given session and returns the result.
+  """
+
+  def get(self):
+    self.response.headers['Content-Type'] = 'text/plain'
+
+    # extract the statement to be run
+    statement = self.request.get('statement')
+    if not statement:
+      return
+
+    # the python compiler doesn't like network line endings
+    statement = statement.replace('\r\n', '\n')
+
+    # add a couple newlines at the end of the statement. this makes
+    # single-line expressions such as 'class Foo: pass' evaluate happily.
+    statement += '\n\n'
+
+    # log and compile the statement up front
+    try:
+      logging.info('Compiling and evaluating:\n%s' % statement)
+      compiled = compile(statement, '<string>', 'single')
+    except:
+      self.response.out.write(traceback.format_exc())
+      return
+
+    # create a dedicated module to be used as this statement's __main__
+    statement_module = new.module('__main__')
+
+    # use this request's __builtin__, since it changes on each request.
+    # this is needed for import statements, among other things.
+    import __builtin__
+    statement_module.__builtins__ = __builtin__
+
+    # load the session from the datastore
+    session = Session.get(self.request.get('session'))
+
+    # swap in our custom module for __main__. then unpickle the session
+    # globals, run the statement, and re-pickle the session globals, all
+    # inside it.
+    old_main = sys.modules.get('__main__')
+    try:
+      sys.modules['__main__'] = statement_module
+      statement_module.__name__ = '__main__'
+
+      # re-evaluate the unpicklables
+      for code in session.unpicklables:
+        exec code in statement_module.__dict__
+
+      # re-initialize the globals
+      for name, val in session.globals_dict().items():
+        try:
+          statement_module.__dict__[name] = val
+        except:
+          msg = 'Dropping %s since it could not be unpickled.\n' % name
+          self.response.out.write(msg)
+          logging.warning(msg + traceback.format_exc())
+          session.remove_global(name)
+
+      # run!
+      old_globals = dict(statement_module.__dict__)
+      try:
+        old_stdout = sys.stdout
+        old_stderr = sys.stderr
+        try:
+          sys.stdout = self.response.out
+          sys.stderr = self.response.out
+          exec compiled in statement_module.__dict__
+        finally:
+          sys.stdout = old_stdout
+          sys.stderr = old_stderr
+      except:
+        self.response.out.write(traceback.format_exc())
+        return
+
+      # extract the new globals that this statement added
+      new_globals = {}
+      for name, val in statement_module.__dict__.items():
+        if name not in old_globals or val != old_globals[name]:
+          new_globals[name] = val
+
+      if True in [isinstance(val, UNPICKLABLE_TYPES)
+                  for val in new_globals.values()]:
+        # this statement added an unpicklable global. store the statement and
+        # the names of all of the globals it added in the unpicklables.
+        session.add_unpicklable(statement, new_globals.keys())
+        logging.debug('Storing this statement as an unpicklable.')
+
+      else:
+        # this statement didn't add any unpicklables. pickle and store the
+        # new globals back into the datastore.
+        for name, val in new_globals.items():
+          if not name.startswith('__'):
+            session.set_global(name, val)
+
+    finally:
+      sys.modules['__main__'] = old_main
+
+    session.put()
+
+
+def main():
+  application = webapp.WSGIApplication(
+    [('/gae_shell/', FrontPageHandler),
+     ('/gae_shell/shell.do', StatementHandler)], debug=_DEBUG)
+  wsgiref.handlers.CGIHandler().run(application)
+
+
+if __name__ == '__main__':
+  main()
diff --git a/scripts/app_engine_server/gae_shell/shell.py~ b/scripts/app_engine_server/gae_shell/shell.py~
new file mode 100755
index 0000000..dee9fdb
--- /dev/null
+++ b/scripts/app_engine_server/gae_shell/shell.py~
@@ -0,0 +1,308 @@
+#!/usr/bin/python
+#
+# Copyright 2007 Google Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+An interactive, stateful AJAX shell that runs Python code on the server.
+
+Part of http://code.google.com/p/google-app-engine-samples/.
+
+May be run as a standalone app or in an existing app as an admin-only handler.
+Can be used for system administration tasks, as an interactive way to try out
+APIs, or as a debugging aid during development.
+
+The logging, os, sys, db, and users modules are imported automatically.
+
+Interpreter state is stored in the datastore so that variables, function
+definitions, and other values in the global and local namespaces can be used
+across commands.
+
+To use the shell in your app, copy shell.py, static/*, and templates/* into
+your app's source directory. Then, copy the URL handlers from app.yaml into
+your app.yaml.
+
+TODO: unit tests!
+"""
+
+import logging
+import new
+import os
+import pickle
+import sys
+import traceback
+import types
+import wsgiref.handlers
+
+from google.appengine.api import users
+from google.appengine.ext import db
+from google.appengine.ext import webapp
+from google.appengine.ext.webapp import template
+
+
+# Set to True if stack traces should be shown in the browser, etc.
+_DEBUG = True
+
+# The entity kind for shell sessions. Feel free to rename to suit your app.
+_SESSION_KIND = '_Shell_Session'
+
+# Types that can't be pickled.
+UNPICKLABLE_TYPES = (
+  types.ModuleType,
+  types.TypeType,
+  types.ClassType,
+  types.FunctionType,
+  )
+
+# Unpicklable statements to seed new sessions with.
+INITIAL_UNPICKLABLES = [
+  'import logging',
+  'import os',
+  'import sys',
+  'from google.appengine.ext import db',
+  'from google.appengine.api import users',
+  ]
+
+
+class Session(db.Model):
+  """A shell session. Stores the session's globals.
+
+  Each session globals is stored in one of two places:
+
+  If the global is picklable, it's stored in the parallel globals and
+  global_names list properties. (They're parallel lists to work around the
+  unfortunate fact that the datastore can't store dictionaries natively.)
+
+  If the global is not picklable (e.g. modules, classes, and functions), or if
+  it was created by the same statement that created an unpicklable global,
+  it's not stored directly. Instead, the statement is stored in the
+  unpicklables list property. On each request, before executing the current
+  statement, the unpicklable statements are evaluated to recreate the
+  unpicklable globals.
+
+  The unpicklable_names property stores all of the names of globals that were
+  added by unpicklable statements. When we pickle and store the globals after
+  executing a statement, we skip the ones in unpicklable_names.
+
+  Using Text instead of string is an optimization. We don't query on any of
+  these properties, so they don't need to be indexed.
+  """
+  global_names = db.ListProperty(db.Text)
+  globals = db.ListProperty(db.Blob)
+  unpicklable_names = db.ListProperty(db.Text)
+  unpicklables = db.ListProperty(db.Text)
+
+  def set_global(self, name, value):
+    """Adds a global, or updates it if it already exists.
+
+    Also removes the global from the list of unpicklable names.
+
+    Args:
+      name: the name of the global to remove
+      value: any picklable value
+    """
+    blob = db.Blob(pickle.dumps(value))
+
+    if name in self.global_names:
+      index = self.global_names.index(name)
+      self.globals[index] = blob
+    else:
+      self.global_names.append(db.Text(name))
+      self.globals.append(blob)
+
+    self.remove_unpicklable_name(name)
+
+  def remove_global(self, name):
+    """Removes a global, if it exists.
+
+    Args:
+      name: string, the name of the global to remove
+    """
+    if name in self.global_names:
+      index = self.global_names.index(name)
+      del self.global_names[index]
+      del self.globals[index]
+
+  def globals_dict(self):
+    """Returns a dictionary view of the globals.
+    """
+    return dict((name, pickle.loads(val))
+                for name, val in zip(self.global_names, self.globals))
+
+  def add_unpicklable(self, statement, names):
+    """Adds a statement and list of names to the unpicklables.
+
+    Also removes the names from the globals.
+
+    Args:
+      statement: string, the statement that created new unpicklable global(s).
+      names: list of strings; the names of the globals created by the statement.
+    """
+    self.unpicklables.append(db.Text(statement))
+
+    for name in names:
+      self.remove_global(name)
+      if name not in self.unpicklable_names:
+        self.unpicklable_names.append(db.Text(name))
+
+  def remove_unpicklable_name(self, name):
+    """Removes a name from the list of unpicklable names, if it exists.
+
+    Args:
+      name: string, the name of the unpicklable global to remove
+    """
+    if name in self.unpicklable_names:
+      self.unpicklable_names.remove(name)
+
+
+class FrontPageHandler(webapp.RequestHandler):
+  """Creates a new session and renders the shell.html template.
+  """
+
+  def get(self):
+    # set up the session. TODO: garbage collect old shell sessions
+    session_key = self.request.get('session')
+    if session_key:
+      session = Session.get(session_key)
+    else:
+      # create a new session
+      session = Session()
+      session.unpicklables = [db.Text(line) for line in INITIAL_UNPICKLABLES]
+      session_key = session.put()
+
+    template_file = os.path.join(os.path.dirname(__file__), 'templates',
+                                 'shell.html')
+    session_url = '/?session=%s' % session_key
+    vars = { 'server_software': os.environ['SERVER_SOFTWARE'],
+             'python_version': sys.version,
+             'session': str(session_key),
+             'user': users.get_current_user(),
+             'login_url': users.create_login_url(session_url),
+             'logout_url': users.create_logout_url(session_url),
+             }
+    rendered = webapp.template.render(template_file, vars, debug=_DEBUG)
+    self.response.out.write(rendered)
+
+
+class StatementHandler(webapp.RequestHandler):
+  """Evaluates a python statement in a given session and returns the result.
+  """
+
+  def get(self):
+    self.response.headers['Content-Type'] = 'text/plain'
+
+    # extract the statement to be run
+    statement = self.request.get('statement')
+    if not statement:
+      return
+
+    # the python compiler doesn't like network line endings
+    statement = statement.replace('\r\n', '\n')
+
+    # add a couple newlines at the end of the statement. this makes
+    # single-line expressions such as 'class Foo: pass' evaluate happily.
+    statement += '\n\n'
+
+    # log and compile the statement up front
+    try:
+      logging.info('Compiling and evaluating:\n%s' % statement)
+      compiled = compile(statement, '<string>', 'single')
+    except:
+      self.response.out.write(traceback.format_exc())
+      return
+
+    # create a dedicated module to be used as this statement's __main__
+    statement_module = new.module('__main__')
+
+    # use this request's __builtin__, since it changes on each request.
+    # this is needed for import statements, among other things.
+    import __builtin__
+    statement_module.__builtins__ = __builtin__
+
+    # load the session from the datastore
+    session = Session.get(self.request.get('session'))
+
+    # swap in our custom module for __main__. then unpickle the session
+    # globals, run the statement, and re-pickle the session globals, all
+    # inside it.
+    old_main = sys.modules.get('__main__')
+    try:
+      sys.modules['__main__'] = statement_module
+      statement_module.__name__ = '__main__'
+
+      # re-evaluate the unpicklables
+      for code in session.unpicklables:
+        exec code in statement_module.__dict__
+
+      # re-initialize the globals
+      for name, val in session.globals_dict().items():
+        try:
+          statement_module.__dict__[name] = val
+        except:
+          msg = 'Dropping %s since it could not be unpickled.\n' % name
+          self.response.out.write(msg)
+          logging.warning(msg + traceback.format_exc())
+          session.remove_global(name)
+
+      # run!
+      old_globals = dict(statement_module.__dict__)
+      try:
+        old_stdout = sys.stdout
+        old_stderr = sys.stderr
+        try:
+          sys.stdout = self.response.out
+          sys.stderr = self.response.out
+          exec compiled in statement_module.__dict__
+        finally:
+          sys.stdout = old_stdout
+          sys.stderr = old_stderr
+      except:
+        self.response.out.write(traceback.format_exc())
+        return
+
+      # extract the new globals that this statement added
+      new_globals = {}
+      for name, val in statement_module.__dict__.items():
+        if name not in old_globals or val != old_globals[name]:
+          new_globals[name] = val
+
+      if True in [isinstance(val, UNPICKLABLE_TYPES)
+                  for val in new_globals.values()]:
+        # this statement added an unpicklable global. store the statement and
+        # the names of all of the globals it added in the unpicklables.
+        session.add_unpicklable(statement, new_globals.keys())
+        logging.debug('Storing this statement as an unpicklable.')
+
+      else:
+        # this statement didn't add any unpicklables. pickle and store the
+        # new globals back into the datastore.
+        for name, val in new_globals.items():
+          if not name.startswith('__'):
+            session.set_global(name, val)
+
+    finally:
+      sys.modules['__main__'] = old_main
+
+    session.put()
+
+
+def main():
+  application = webapp.WSGIApplication(
+    [('/', FrontPageHandler),
+     ('/shell.do', StatementHandler)], debug=_DEBUG)
+  wsgiref.handlers.CGIHandler().run(application)
+
+
+if __name__ == '__main__':
+  main()
diff --git a/scripts/app_engine_server/gae_shell/static/shell.js b/scripts/app_engine_server/gae_shell/static/shell.js
new file mode 100644
index 0000000..4aa1583
--- /dev/null
+++ b/scripts/app_engine_server/gae_shell/static/shell.js
@@ -0,0 +1,195 @@
+// Copyright 2007 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/**
+ * @fileoverview
+ * Javascript code for the interactive AJAX shell.
+ *
+ * Part of http://code.google.com/p/google-app-engine-samples/.
+ *
+ * Includes a function (shell.runStatement) that sends the current python
+ * statement in the shell prompt text box to the server, and a callback
+ * (shell.done) that displays the results when the XmlHttpRequest returns.
+ *
+ * Also includes cross-browser code (shell.getXmlHttpRequest) to get an
+ * XmlHttpRequest.
+ */
+
+/**
+ * Shell namespace.
+ * @type {Object}
+ */
+var shell = {}
+
+/**
+ * The shell history. history is an array of strings, ordered oldest to
+ * newest. historyCursor is the current history element that the user is on.
+ *
+ * The last history element is the statement that the user is currently
+ * typing. When a statement is run, it's frozen in the history, a new history
+ * element is added to the end of the array for the new statement, and
+ * historyCursor is updated to point to the new element.
+ *
+ * @type {Array}
+ */
+shell.history = [''];
+
+/**
+ * See {shell.history}
+ * @type {number}
+ */
+shell.historyCursor = 0;
+
+/**
+ * A constant for the XmlHttpRequest 'done' state.
+ * @type Number
+ */
+shell.DONE_STATE = 4;
+
+/**
+ * A cross-browser function to get an XmlHttpRequest object.
+ *
+ * @return {XmlHttpRequest?} a new XmlHttpRequest
+ */
+shell.getXmlHttpRequest = function() {
+  if (window.XMLHttpRequest) {
+    return new XMLHttpRequest();
+  } else if (window.ActiveXObject) {
+    try {
+      return new ActiveXObject('Msxml2.XMLHTTP');
+    } catch(e) {
+      return new ActiveXObject('Microsoft.XMLHTTP');
+    }
+  }
+
+  return null;
+};
+
+/**
+ * This is the prompt textarea's onkeypress handler. Depending on the key that
+ * was pressed, it will run the statement, navigate the history, or update the
+ * current statement in the history.
+ *
+ * @param {Event} event the keypress event
+ * @return {Boolean} false to tell the browser not to submit the form.
+ */
+shell.onPromptKeyPress = function(event) {
+  var statement = document.getElementById('statement');
+
+  if (this.historyCursor == this.history.length - 1) {
+    // we're on the current statement. update it in the history before doing
+    // anything.
+    this.history[this.historyCursor] = statement.value;
+  }
+
+  // should we pull something from the history?
+  if (event.ctrlKey && event.keyCode == 38 /* up arrow */) {
+    if (this.historyCursor > 0) {
+      statement.value = this.history[--this.historyCursor];
+    }
+    return false;
+  } else if (event.ctrlKey && event.keyCode == 40 /* down arrow */) {
+    if (this.historyCursor < this.history.length - 1) {
+      statement.value = this.history[++this.historyCursor];
+    }
+    return false;
+  } else if (!event.altKey) {
+    // probably changing the statement. update it in the history.
+    this.historyCursor = this.history.length - 1;
+    this.history[this.historyCursor] = statement.value;
+  }
+
+  // should we submit?
+  var ctrlEnter = (document.getElementById('submit_key').value == 'ctrl-enter');
+  if (event.keyCode == 13 /* enter */ && !event.altKey && !event.shiftKey &&
+      event.ctrlKey == ctrlEnter) {
+    return this.runStatement();
+  }
+};
+
+/**
+ * The XmlHttpRequest callback. If the request succeeds, it adds the command
+ * and its resulting output to the shell history div.
+ *
+ * @param {XmlHttpRequest} req the XmlHttpRequest we used to send the current
+ *     statement to the server
+ */
+shell.done = function(req) {
+  if (req.readyState == this.DONE_STATE) {
+    var statement = document.getElementById('statement')
+    statement.className = 'prompt';
+
+    // add the command to the shell output
+    var output = document.getElementById('output');
+
+    output.value += '\n>>> ' + statement.value;
+    statement.value = '';
+
+    // add a new history element
+    this.history.push('');
+    this.historyCursor = this.history.length - 1;
+
+    // add the command's result
+    var result = req.responseText.replace(/^\s*|\s*$/g, '');  // trim whitespace
+    if (result != '')
+      output.value += '\n' + result;
+
+    // scroll to the bottom
+    output.scrollTop = output.scrollHeight;
+    if (output.createTextRange) {
+      var range = output.createTextRange();
+      range.collapse(false);
+      range.select();
+    }
+  }
+};
+
+/**
+ * This is the form's onsubmit handler. It sends the python statement to the
+ * server, and registers shell.done() as the callback to run when it returns.
+ *
+ * @return {Boolean} false to tell the browser not to submit the form.
+ */
+shell.runStatement = function() {
+  var form = document.getElementById('form');
+
+  // build a XmlHttpRequest
+  var req = this.getXmlHttpRequest();
+  if (!req) {
+    document.getElementById('ajax-status').innerHTML =
+        "<span class='error'>Your browser doesn't support AJAX. :(</span>";
+    return false;
+  }
+
+  req.onreadystatechange = function() { shell.done(req); };
+
+  // build the query parameter string
+  var params = '';
+  for (i = 0; i < form.elements.length; i++) {
+    var elem = form.elements[i];
+    if (elem.type != 'submit' && elem.type != 'button' && elem.id != 'caret') {
+      var value = escape(elem.value).replace(/\+/g, '%2B'); // escape ignores +
+      params += '&' + elem.name + '=' + value;
+    }
+  }
+
+  // send the request and tell the user.
+  document.getElementById('statement').className = 'prompt processing';
+  req.open(form.method, form.action + '?' + params, true);
+  req.setRequestHeader('Content-type',
+                       'application/x-www-form-urlencoded;charset=UTF-8');
+  req.send(null);
+
+  return false;
+};
diff --git a/scripts/app_engine_server/gae_shell/static/spinner.gif b/scripts/app_engine_server/gae_shell/static/spinner.gif
new file mode 100644
index 0000000..3e58d6e
--- /dev/null
+++ b/scripts/app_engine_server/gae_shell/static/spinner.gif
diff --git a/scripts/app_engine_server/gae_shell/templates/shell.html b/scripts/app_engine_server/gae_shell/templates/shell.html
new file mode 100644
index 0000000..123b200
--- /dev/null
+++ b/scripts/app_engine_server/gae_shell/templates/shell.html
@@ -0,0 +1,122 @@
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
+ "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
+<html>
+<head>
+<meta http-equiv="content-type" content="text/html; charset=utf-8" />
+<title> Interactive Shell </title>
+<script type="text/javascript" src="/gae_shell/static/shell.js"></script>
+<style type="text/css">
+body {
+  font-family: monospace;
+  font-size: 10pt;
+}
+
+p {
+  margin: 0.5em;
+}
+
+.prompt, #output {
+  width: 45em;
+  border: 1px solid silver;
+  background-color: #f5f5f5;
+  font-size: 10pt;
+  margin: 0.5em;
+  padding: 0.5em;
+  padding-right: 0em;
+  overflow-x: hidden;
+}
+
+#toolbar {
+  margin-left: 0.5em;
+  padding-left: 0.5em;
+}
+
+#caret {
+  width: 2.5em;
+  margin-right: 0px;
+  padding-right: 0px;
+  border-right: 0px;
+}
+
+#statement {
+  width: 43em;
+  margin-left: -1em;
+  padding-left: 0px;
+  border-left: 0px;
+  background-position: top right;
+  background-repeat: no-repeat;
+}
+
+.processing {
+  background-image: url("/gae_shell/static/spinner.gif");
+}
+
+#ajax-status {
+  font-weight: bold;
+}
+
+.message {
+  color: #8AD;
+  font-weight: bold;
+  font-style: italic;
+}
+
+.error {
+  color: #F44;
+}
+
+.username {
+  font-weight: bold;
+}
+
+</style>
+</head>
+
+<body>
+
+<p> Interactive server-side Python shell for
+<a href="http://code.google.com/appengine/">Google App Engine</a>.
+(<a href="http://code.google.com/p/google-app-engine-samples/">source</a>)
+</p>
+
+<textarea id="output" rows="22" readonly="readonly">
+{{ server_software }}
+Python {{ python_version }}
+</textarea>
+
+<form id="form" action="shell.do" method="get">
+  <nobr>
+  <textarea class="prompt" id="caret" readonly="readonly" rows="4"
+            onfocus="document.getElementById('statement').focus()"
+            >&gt;&gt;&gt;</textarea>
+  <textarea class="prompt" name="statement" id="statement" rows="4"
+            onkeypress="return shell.onPromptKeyPress(event);"></textarea>
+  </nobr>
+  <input type="hidden" name="session" value="{{ session }}" />
+  <input type="submit" style="display: none" />
+</form>
+
+<p id="ajax-status"></p>
+
+<p id="toolbar">
+{% if user %}
+  <span class="username">{{ user.nickname }}</span>
+  (<a href="{{ logout_url }}">log out</a>)
+{% else %}
+  <a href="{{ login_url }}">log in</a>
+{% endif %}
+ | Ctrl-Up/Down for history |
+<select id="submit_key">
+  <option value="enter">Enter</option>
+  <option value="ctrl-enter" selected="selected">Ctrl-Enter</option>
+</select>
+<label for="submit_key">submits</label>
+</p>
+
+<script type="text/javascript">
+document.getElementById('statement').focus();
+</script>
+
+</body>
+</html>
+