# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1391190797 -3600
# Node ID 61b570ca9d2f0abbd756b9bf28a57ede5b8b5171
# Parent  6436bd5abb403699b7a5089fcce7cca8bb94e5a4
Implemented switching to the relaying user in order to queue messages for
forwarding.

diff -r 6436bd5abb40 -r 61b570ca9d2f MoinMessageSupport.py
--- a/MoinMessageSupport.py	Fri Jan 31 18:52:05 2014 +0100
+++ b/MoinMessageSupport.py	Fri Jan 31 18:53:17 2014 +0100
@@ -6,7 +6,7 @@
     @license: GNU GPL (v2 or later), see COPYING.txt for details.
 """
 
-from MoinMoin import config
+from MoinMoin import config, user
 from MoinMoin.Page import Page
 from MoinMoin.action import AttachFile
 from MoinMoin.formatter import text_html
@@ -67,6 +67,8 @@
         # Detect any indicated recipient and change the target page, if
         # appropriate.
 
+        new_user = None
+
         if message.has_key("To"):
             try:
                 parameters = get_recipient_details(request, message["To"], main=True)
@@ -81,15 +83,54 @@
                                   "Details: %s" % exc.message)
                     return
             else:
+                # Recipients with pages can have their messages redirected to
+                # those pages.
+
                 if parameters["type"] == "page":
                     self.page = Page(request, parameters["location"])
                     self.init_store()
 
-                # NOTE: Support "url" for message forwarding.
+                # Recipients with URLs can have their messages forwarded.
+
+                # Recipients accessible via relays have their messages
+                # forwarded.
+
+                elif parameters["type"] in ("url", "relay"):
+
+                    # Get the relaying user page and select it.
+
+                    relaying_user = getattr(self.request.cfg, "moinmessage_gpg_relaying_user")
+                    relaying_page = relaying_user and get_local_homepage(request, relaying_user)
+
+                    if not relaying_page:
+                        writeHeaders(request, "text/plain", getMetadata(self.page), "403 Forbidden")
+                        request.write("This site is not able to forward the message to the recipient.")
+                        return
+
+                    self.page = Page(request, relaying_page)
+                    self.init_store()
+                    new_user = relaying_user
+
+                    # The stored messages should then be processed
+                    # asynchronously.
+
+                    # NOTE: An action should be able to process stored messages,
+                    # NOTE: by invoking code that is also used asynchronously.
+
+        # Switch to the relaying user if necessary.
+
+        if new_user:
+            user = request.user
+            request.user = get_user(request, new_user) or user
+            request.user.auth_method = "pgp-overridden"
 
         # Handle the parsed message.
 
-        self.handle_message(message)
+        try:
+            self.handle_message(message)
+        finally:
+            if new_user:
+                request.user = user
 
     def handle_message(self, message):
 
@@ -174,7 +215,7 @@
 
         # Accept any message whose sender was authenticated by the PGP method.
 
-        if request.user and request.user.valid and request.user.auth_method == "pgp":
+        if request.user and request.user.valid and request.user.auth_method in ("pgp", "pgp-overridden"):
 
             # Handle the embedded message.
 
@@ -277,6 +318,21 @@
 
 # Utility functions.
 
+def get_user(request, username):
+
+    "Return the user having the given 'username'."
+
+    uid = user.getUserId(request, username)
+
+    # If the user does not exist, just return None.
+
+    if not uid:
+        return None
+
+    # Otherwise, return the requested user.
+
+    return user.User(request, uid)
+
 def get_homedir(request):
 
     "Locate the GPG home directory."
@@ -321,17 +377,30 @@
     subpage = getattr(request.cfg, "moinmessage_gpg_recipients_page", "MoinMessageRecipientsDict")
 
     if not main:
-        homedetails = getInterwikiHomePage(request)
-
-        if homedetails:
-            homewiki, homepage = homedetails
-            if homewiki == "Self":
-                recipients = getWikiDict("%s/%s" % (homepage, subpage), request)
-                if recipients:
-                    return filter_recipients(recipients, sending, fetching)
+        homepage = get_local_homepage(request, None)
+        recipients = getWikiDict("%s/%s" % (homepage, subpage), request)
+        if recipients:
+            return filter_recipients(recipients, sending, fetching)
 
     return filter_recipients(getWikiDict(subpage, request), sending, fetching)
 
+def get_local_homepage(request, username):
+
+    """
+    Using the 'request', return the homepage for the given 'username' or None if
+    no local homepage exists for the user. If 'username' is None, the current
+    user's homepage is located.
+    """
+
+    homedetails = getInterwikiHomePage(request, username)
+
+    if homedetails:
+        homewiki, homepage = homedetails
+        if homewiki == "Self":
+            return homepage
+
+    return None
+
 def get_username_for_fingerprint(request, fingerprint):
 
     """