Open Source Monorail

appengine/monorail/features/inboundemail.py

Index: appengine/monorail/features/inboundemail.py
diff --git a/appengine/monorail/features/inboundemail.py b/appengine/monorail/features/inboundemail.py
new file mode 100644
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+++ b/appengine/monorail/features/inboundemail.py
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+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is govered by a BSD-style
+# license that can be found in the LICENSE file or at
+# https://developers.google.com/open-source/licenses/bsd
+
+"""Handler to process inbound email with issue comments and commands."""
+
+import logging
+import os
+import urllib
+
+from third_party import ezt
+
+from google.appengine.api import mail
+
+import webapp2
+
+from features import commitlogcommands
+from features import notify
+from framework import emailfmt
+from framework import framework_constants
+from framework import monorailrequest
+from framework import permissions
+from framework import sql
+from framework import template_helpers
+from proto import project_pb2
+from services import issue_svc
+from services import user_svc
+
+
+TEMPLATE_PATH_BASE = framework_constants.TEMPLATE_PATH
+
+MSG_TEMPLATES = {
+    'banned': 'features/inboundemail-banned.ezt',
+    'body_too_long': 'features/inboundemail-body-too-long.ezt',
+    'project_not_found': 'features/inboundemail-project-not-found.ezt',
+    'not_a_reply': 'features/inboundemail-not-a-reply.ezt',
+    'no_account': 'features/inboundemail-no-account.ezt',
+    'no_artifact': 'features/inboundemail-no-artifact.ezt',
+    'no_perms': 'features/inboundemail-no-perms.ezt',
+    'replies_disabled': 'features/inboundemail-replies-disabled.ezt',
+    }
+
+
+class InboundEmail(webapp2.RequestHandler):
+  """Servlet to handle inbound email messages."""
+
+  def __init__(self, request, response, services=None, *args, **kwargs):
+    super(InboundEmail, self).__init__(request, response, *args, **kwargs)
+    self.services = services or self.app.config.get('services')
+    self._templates = {}
+    for name, template_path in MSG_TEMPLATES.iteritems():
+      self._templates[name] = template_helpers.MonorailTemplate(
+          TEMPLATE_PATH_BASE + template_path,
+          compress_whitespace=False, base_format=ezt.FORMAT_RAW)
+
+  def get(self, project_addr=None):
+    logging.info('\n\n\nGET for InboundEmail and project_addr is %r',
+                 project_addr)
+    self.Handler(mail.InboundEmailMessage(self.request.body),
+                 urllib.unquote(project_addr))
+
+  def post(self, project_addr=None):
+    logging.info('\n\n\nPOST for InboundEmail and project_addr is %r',
+                 project_addr)
+    self.Handler(mail.InboundEmailMessage(self.request.body),
+                 urllib.unquote(project_addr))
+
+  def Handler(self, inbound_email_message, project_addr):
+    """Process an inbound email message."""
+    msg = inbound_email_message.original
+    email_tasks = self.ProcessMail(msg, project_addr)
+
+    if email_tasks:
+      notify.AddAllEmailTasks(email_tasks)
+
+  def ProcessMail(self, msg, project_addr):
+    """Process an inbound email message."""
+    # TODO(jrobbins): If the message is HUGE, don't even try to parse
+    # it. Silently give up.
+
+    (from_addr, to_addrs, cc_addrs, references, subject,
+     body) = emailfmt.ParseEmailMessage(msg)
+
+    logging.info('Proj addr:  %r', project_addr)
+    logging.info('From addr:  %r', from_addr)
+    logging.info('Subject:    %r', subject)
+    logging.info('To:         %r', to_addrs)
+    logging.info('Cc:         %r', cc_addrs)
+    logging.info('References: %r', references)
+    logging.info('Body:       %r', body)
+
+    # If message body is very large, reject it and send an error email.
+    if emailfmt.IsBodyTooBigToParse(body):
+      return _MakeErrorMessageReplyTask(
+          project_addr, from_addr, self._templates['body_too_long'])
+
+    # Make sure that the project reply-to address is in the To: line.
+    if not emailfmt.IsProjectAddressOnToLine(project_addr, to_addrs):
+      return None
+
+    # Identify the project and artifact to update.
+    project_name, local_id = emailfmt.IdentifyProjectAndIssue(
+        project_addr, subject)
+    if not project_addr or not local_id:
+      logging.info('Could not identify issue: %s %s', project_addr, subject)
+      # No error message, because message was probably not intended for us.
+      return None
+
+    cnxn = sql.MonorailConnection()
+    if self.services.cache_manager:
+      self.services.cache_manager.DoDistributedInvalidation(cnxn)
+
+    project = self.services.project.GetProjectByName(cnxn, project_name)
+
+    if not project or project.state != project_pb2.ProjectState.LIVE:
+      return _MakeErrorMessageReplyTask(
+          project_addr, from_addr, self._templates['project_not_found'])
+
+    if not project.process_inbound_email:
+      return _MakeErrorMessageReplyTask(
+          project_addr, from_addr, self._templates['replies_disabled'],
+          project_name=project_name)
+
+    # Verify that this is a reply to a notification that we could have sent.
+    if not os.environ['SERVER_SOFTWARE'].startswith('Development'):
+      for ref in references:
+        if emailfmt.ValidateReferencesHeader(ref, project, from_addr, subject):
+          break  # Found a message ID that we could have sent.
+      else:
+        return _MakeErrorMessageReplyTask(
+            project_addr, from_addr, self._templates['not_a_reply'])
+
+    # Authenticate the from-addr and perm check.
+    # Note: If the issue summary line is changed, a new thread is created,
+    # and replies to the old thread will no longer work because the subject
+    # line hash will not match, which seems reasonable.
+    try:
+      auth = monorailrequest.AuthData.FromEmail(cnxn, from_addr, self.services)
+      from_user_id = auth.user_id
+    except user_svc.NoSuchUserException:
+      from_user_id = None
+    if not from_user_id:
+      return _MakeErrorMessageReplyTask(
+          project_addr, from_addr, self._templates['no_account'])
+
+    if auth.user_pb.banned:
+      logging.info('Banned user %s tried to post to %s',
+                   from_addr, project_addr)
+      return _MakeErrorMessageReplyTask(
+          project_addr, from_addr, self._templates['banned'])
+
+    perms = permissions.GetPermissions(
+        auth.user_pb, auth.effective_ids, project)
+
+    self.ProcessIssueReply(
+        cnxn, project, local_id, project_addr, from_addr, from_user_id,
+        auth.effective_ids, perms, body)
+
+    return None
+
+  def ProcessIssueReply(
+      self, cnxn, project, local_id, project_addr, from_addr, from_user_id,
+      effective_ids, perms, body):
+    """Examine an issue reply email body and add a comment to the issue.
+
+    Args:
+      cnxn: connection to SQL database.
+      project: Project PB for the project containing the issue.
+      local_id: int ID of the issue being replied to.
+      project_addr: string email address used for outbound emails from
+          that project.
+      from_addr: string email address of the user who sent the email
+          reply to our server.
+      from_user_id: int user ID of user who sent the reply email.
+      effective_ids: set of int user IDs for the user (including any groups),
+          or an empty set if user is not signed in.
+      perms: PermissionSet for the user who sent the reply email.
+      body: string email body text of the reply email.
+
+    Returns:
+      A list of follow-up work items, e.g., to notify other users of
+      the new comment, or to notify the user that their reply was not
+      processed.
+
+    Side-effect:
+      Adds a new comment to the issue, if no error is reported.
+    """
+    try:
+      issue = self.services.issue.GetIssueByLocalID(
+          cnxn, project.project_id, local_id)
+    except issue_svc.NoSuchIssueException:
+      issue = None
+
+    if not issue or issue.deleted:
+      # The referenced issue was not found, e.g., it might have been
+      # deleted, or someone messed with the subject line.  Reject it.
+      return _MakeErrorMessageReplyTask(
+          project_addr, from_addr, self._templates['no_artifact'],
+          artifact_phrase='issue %d' % local_id,
+          project_name=project.project_name)
+
+    if not perms.CanUsePerm(
+        permissions.ADD_ISSUE_COMMENT, effective_ids, project,
+        permissions.GetRestrictions(issue)):
+      return _MakeErrorMessageReplyTask(
+          project_addr, from_addr, self._templates['no_perms'],
+          artifact_phrase='issue %d' % local_id,
+          project_name=project.project_name)
+    allow_edit = permissions.CanEditIssue(
+        effective_ids, perms, project, issue)
+    # TODO(jrobbins): if the user does not have EDIT_ISSUE and the inbound
+    # email tries to make an edit, send back an error message.
+
+    lines = body.strip().split('\n')
+    uia = commitlogcommands.UpdateIssueAction(local_id)
+    uia.Parse(cnxn, project.project_name, from_user_id, lines, self.services,
+              strip_quoted_lines=True)
+    uia.Run(cnxn, self.services, allow_edit=allow_edit)
+
+
+def _MakeErrorMessageReplyTask(
+    project_addr, sender_addr, template, **callers_page_data):
+  """Return a new task to send an error message email.
+
+  Args:
+    project_addr: string email address that the inbound email was delivered to.
+    sender_addr: string email address of user who sent the email that we could
+        not process.
+    template: EZT template used to generate the email error message.  The
+        first line of this generated text will be used as the subject line.
+    callers_page_data: template data dict for body of the message.
+
+  Returns:
+    A list with a single Email task that can be enqueued to
+    actually send the email.
+
+  Raises:
+    ValueError: if the template does begin with a "Subject:" line.
+  """
+  email_data = {
+      'project_addr': project_addr,
+      'sender_addr': sender_addr
+      }
+  email_data.update(callers_page_data)
+
+  generated_lines = template.GetResponse(email_data)
+  subject, body = generated_lines.split('\n', 1)
+  if subject.startswith('Subject: '):
+    subject = subject[len('Subject: '):]
+  else:
+    raise ValueError('Email template does not begin with "Subject:" line.')
+
+  email_task = dict(to=sender_addr, subject=subject, body=body,
+                    from_addr=emailfmt.NoReplyAddress())
+  logging.info('sending email error reply: %r', email_task)
+
+  return [email_task]