# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1454197526 -3600
# Node ID fc1efc973849fbb1047fb43910529b15782998c7
# Parent  6e8f43c29e71ef2d990c6a2eaf358c92ffff8237
Introduced the access control list scheduling function plus argument support.
Moved scheduling function lookup into the scheduling module as part of the
revised function invocation parsing activity, employing a new text processing
module in imiptools.
Added tests of the access control list functionality.

diff -r 6e8f43c29e71 -r fc1efc973849 imiptools/handlers/resource.py
--- a/imiptools/handlers/resource.py	Sat Jan 30 17:24:39 2016 +0100
+++ b/imiptools/handlers/resource.py	Sun Jan 31 00:45:26 2016 +0100
@@ -22,8 +22,7 @@
 from imiptools.data import get_address, to_part, uri_dict
 from imiptools.handlers import Handler
 from imiptools.handlers.common import CommonFreebusy, CommonEvent
-from imiptools.handlers.scheduling import apply_scheduling_functions, \
-                                          scheduling_functions
+from imiptools.handlers.scheduling import apply_scheduling_functions
 
 class ResourceHandler(CommonEvent, Handler):
 
@@ -168,10 +167,6 @@
         functions = self.get_preferences().get("scheduling_function",
             "schedule_in_freebusy").split("\n")
 
-        # Obtain the actual scheduling functions.
-
-        functions = map(scheduling_functions.get, functions)
-
         return apply_scheduling_functions(functions, self)
 
 class Event(ResourceHandler):
diff -r 6e8f43c29e71 -r fc1efc973849 imiptools/handlers/scheduling/__init__.py
--- a/imiptools/handlers/scheduling/__init__.py	Sat Jan 30 17:24:39 2016 +0100
+++ b/imiptools/handlers/scheduling/__init__.py	Sun Jan 31 00:45:26 2016 +0100
@@ -19,7 +19,9 @@
 this program.  If not, see <http://www.gnu.org/licenses/>.
 """
 
+from imiptools.text import parse_line
 from imiptools.handlers.scheduling.manifest import scheduling_functions
+import re
 
 def apply_scheduling_functions(functions, handler):
 
@@ -28,9 +30,13 @@
     'handler'.
     """
 
+    # Obtain the actual scheduling functions with arguments.
+
+    functions = get_scheduling_function_calls(functions)
+
     response = "ACCEPTED"
 
-    for fn in functions:
+    for fn, args in functions:
 
         # NOTE: Should signal an error for incorrectly configured resources.
 
@@ -41,7 +47,7 @@
         # declines or gives a null response.
 
         else:
-            result = fn(handler)
+            result = fn(handler, args)
 
             # Return a negative result immediately.
 
@@ -56,4 +62,24 @@
 
     return response
 
+def get_scheduling_function_calls(lines):
+
+    """
+    Parse the given 'lines', returning a list of (function, arguments) tuples,
+    with each function being a genuine function object and with the arguments
+    being a list of strings.
+
+    Each of the 'lines' should employ the function name and argument strings
+    separated by whitespace, with any whitespace inside arguments quoted using
+    single or double quotes.
+    """
+
+    functions = []
+
+    for line in lines:
+        parts = parse_line(line)
+        functions.append((scheduling_functions.get(parts[0]), parts[1:]))
+
+    return functions
+
 # vim: tabstop=4 expandtab shiftwidth=4
diff -r 6e8f43c29e71 -r fc1efc973849 imiptools/handlers/scheduling/access.py
--- a/imiptools/handlers/scheduling/access.py	Sat Jan 30 17:24:39 2016 +0100
+++ b/imiptools/handlers/scheduling/access.py	Sun Jan 31 00:45:26 2016 +0100
@@ -19,9 +19,97 @@
 this program.  If not, see <http://www.gnu.org/licenses/>.
 """
 
-from imiptools.data import get_address
+from imiptools.data import get_address, get_addresses
+from imiptools.text import parse_line
+
+def access_control_list(handler, args):
+
+    """
+    Attempt to schedule the current object of the given 'handler' using an
+    access control list provided in the given 'args', applying it to the
+    organiser.
+    """
+
+    # Obtain either a file from the user's preferences directory...
+
+    if not args:
+        acl = handler.get_preferences().get("acl")
+        lines = acl.strip().split("\n")
+
+    # Or obtain the contents of a specific file.
+
+    else:
+        try:
+            f = open(args[0])
+        except IOError:
+            return None
+        try:
+            lines = f.readlines()
+        finally:
+            f.close()
+
+    # Use the current object's identities with the ACL rules.
+
+    organiser = get_address(handler.obj.get_value("ORGANIZER"))
+    attendees = get_addresses(handler.obj.get_values("ATTENDEE"))
+
+    response = None
+
+    for line in lines:
+        parts = parse_line(line.strip())
+
+        # Skip empty lines.
+
+        if not parts:
+            continue
 
-def same_domain_only(handler):
+        # Accept either a single word with an action or a rule.
+        # NOTE: Should signal an error with the format.
+
+        if len(parts) == 1:
+            action = parts[0]
+        elif len(parts) >= 3:
+            action, role, identities = parts[0], parts[1], map(get_address, parts[2:])
+        else:
+            return None
+
+        if action.lower() == "accept":
+            result = "ACCEPTED"
+        elif action.lower() in ["decline", "reject"]:
+            result = "DECLINED"
+        else:
+            return None
+
+        # With only an action, prepare a default response in case none of
+        # the rules match.
+
+        if len(parts) == 1:
+            response = result
+            continue
+
+        # Where no default has been set, use an implicit default based on
+        # the action appearing in a rule.
+
+        elif not response:
+            response = result == "ACCEPTED" and "DECLINED" or "ACCEPTED"
+
+        # Interpret a rule, attempting to match identities to properties.
+
+        if role.lower() in ["organiser", "organizer"]:
+            match = organiser in identities
+        elif role.lower() in ["attendee", "attendees"]:
+            match = set(attendees).intersection(identities)
+        else:
+            return None
+
+        # Use the result of any match.
+
+        if match:
+            response = result
+
+    return response
+
+def same_domain_only(handler, args):
 
     """
     Attempt to schedule the current object of the given 'handler' if the
@@ -39,6 +127,7 @@
 # Registry of scheduling functions.
 
 scheduling_functions = {
+    "access_control_list" : access_control_list,
     "same_domain_only" : same_domain_only,
     }
 
diff -r 6e8f43c29e71 -r fc1efc973849 imiptools/handlers/scheduling/freebusy.py
--- a/imiptools/handlers/scheduling/freebusy.py	Sat Jan 30 17:24:39 2016 +0100
+++ b/imiptools/handlers/scheduling/freebusy.py	Sun Jan 31 00:45:26 2016 +0100
@@ -25,7 +25,7 @@
                              periods_from, remove_event_periods, \
                              remove_periods
 
-def schedule_in_freebusy(handler, freebusy=None):
+def schedule_in_freebusy(handler, args, freebusy=None):
 
     """
     Attempt to schedule the current object of the given 'handler' in the
@@ -53,7 +53,7 @@
 
     return scheduled and "ACCEPTED" or "DECLINED"
 
-def schedule_corrected_in_freebusy(handler):
+def schedule_corrected_in_freebusy(handler, args):
 
     """
     Attempt to schedule the current object of the given 'handler', correcting
@@ -88,7 +88,7 @@
 
     return scheduled == "ACCEPTED" and (corrected and "COUNTER" or "ACCEPTED") or "DECLINED"
 
-def schedule_next_available_in_freebusy(handler):
+def schedule_next_available_in_freebusy(handler, args):
 
     """
     Attempt to schedule the current object of the given 'handler', correcting
@@ -202,7 +202,7 @@
 
     # Check one last time, reverting the change if not scheduled.
 
-    scheduled = schedule_in_freebusy(handler, busy)
+    scheduled = schedule_in_freebusy(handler, args, busy)
 
     if scheduled == "DECLINED":
         handler.set_object(obj)
diff -r 6e8f43c29e71 -r fc1efc973849 imiptools/text.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/imiptools/text.py	Sun Jan 31 00:45:26 2016 +0100
@@ -0,0 +1,56 @@
+#!/usr/bin/env python
+
+"""
+Parsing of textual content.
+
+Copyright (C) 2016 Paul Boddie <paul@boddie.org.uk>
+
+This program is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free Software
+Foundation; either version 3 of the License, or (at your option) any later
+version.
+
+This program is distributed in the hope that it will be useful, but WITHOUT
+ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+details.
+
+You should have received a copy of the GNU General Public License along with
+this program.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
+import re
+
+# Parsing of lines to obtain functions and arguments.
+
+line_pattern_str = r"(?:" \
+                   r"(?:'(.*?)')" \
+                   r"|" \
+                   r'(?:"(.*?)")' \
+                   r"|" \
+                   r"([^\s]+)" \
+                   r")+" \
+                   r"(?:\s+|$)"
+line_pattern = re.compile(line_pattern_str)
+
+def parse_line(text):
+
+    """
+    Parse the given 'text', returning a list of words separated by whitespace in
+    the input, where whitespace may occur inside words if quoted using single or
+    double quotes.
+    """
+
+    parts = []
+
+    # Match the components of each part.
+
+    for match in line_pattern.finditer(text):
+
+        # Combine the components by traversing the matching groups.
+
+        parts.append(reduce(lambda a, b: (a or "") + (b or ""), match.groups()))
+
+    return parts
+
+# vim: tabstop=4 expandtab shiftwidth=4
diff -r 6e8f43c29e71 -r fc1efc973849 tests/templates/event-request-sauna-acl.txt
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/tests/templates/event-request-sauna-acl.txt	Sun Jan 31 00:45:26 2016 +0100
@@ -0,0 +1,35 @@
+Content-Type: multipart/alternative; boundary="===============0047278175=="
+MIME-Version: 1.0
+From: paul.boddie@example.com
+To: resource-room-sauna@example.com
+Subject: Invitation!
+
+--===============0047278175==
+Content-Type: text/plain; charset="us-ascii"
+MIME-Version: 1.0
+Content-Transfer-Encoding: 7bit
+
+This message contains an event.
+--===============0047278175==
+MIME-Version: 1.0
+Content-Transfer-Encoding: 7bit
+Content-Type: text/calendar; charset="us-ascii"; method="REQUEST"
+
+BEGIN:VCALENDAR
+PRODID:-//imip-agent/test//EN
+METHOD:REQUEST
+VERSION:2.0
+BEGIN:VEVENT
+ORGANIZER:mailto:paul.boddie@example.com
+ATTENDEE;ROLE=CHAIR:mailto:paul.boddie@example.com
+ATTENDEE;RSVP=TRUE:mailto:resource-room-sauna@example.com
+ATTENDEE;RSVP=TRUE:mailto:simon.skunk@example.com
+DTSTAMP:20141125T004600Z
+DTSTART;TZID=Europe/Oslo:20141126T170000
+DTEND;TZID=Europe/Oslo:20141126T174500
+SUMMARY:Meeting at 5pm
+UID:event20@example.com
+END:VEVENT
+END:VCALENDAR
+
+--===============0047278175==--
diff -r 6e8f43c29e71 -r fc1efc973849 tests/test_resource_invitation_constraints_multiple.sh
--- a/tests/test_resource_invitation_constraints_multiple.sh	Sat Jan 30 17:24:39 2016 +0100
+++ b/tests/test_resource_invitation_constraints_multiple.sh	Sun Jan 31 00:45:26 2016 +0100
@@ -3,12 +3,11 @@
 . "`dirname \"$0\"`/common.sh"
 
 USER="mailto:resource-room-sauna@example.com"
-SENDER="mailto:paul.boddie@example.net"
+SENDER="mailto:paul.boddie@example.com"
+OUTSIDESENDER="mailto:paul.boddie@example.net"
 FBFILE="$STORE/$USER/freebusy"
-FBOFFERFILE="$STORE/$USER/freebusy-offers"
 FBSENDERFILE="$STORE/$SENDER/freebusy"
-FBSENDEROTHERFILE="$STORE/$SENDER/freebusy-other/$USER"
-FBSENDERREQUESTS="$STORE/$SENDER/requests"
+FBOUTSIDESENDERFILE="$STORE/$OUTSIDESENDER/freebusy"
 
 mkdir -p "$PREFS/$USER"
 echo 'Europe/Oslo' > "$PREFS/$USER/TZID"
@@ -33,7 +32,7 @@
 
 "$OUTGOING_SCRIPT" $ARGS < "$TEMPLATES/event-request-sauna-outsider.txt" 2>> $ERROR
 
-   grep -q "^20141126T150000Z${TAB}20141126T154500Z" "$FBSENDERFILE" \
+   grep -q "^20141126T150000Z${TAB}20141126T154500Z" "$FBOUTSIDESENDERFILE" \
 && echo "Success" \
 || echo "Failed"
 
@@ -87,3 +86,137 @@
 && grep -q 'FREEBUSY;FBTYPE=BUSY:20141126T150000Z/20141126T154500Z' out3.tmp \
 && echo "Success" \
 || echo "Failed"
+
+# Try a different scheduling function.
+
+ACL="$PWD/acl.tmp"
+
+cat > "$PREFS/$USER/scheduling_function" <<EOF
+schedule_in_freebusy
+access_control_list "$ACL"
+EOF
+
+# Try without an ACL.
+
+cat > "$ACL" <<EOF
+EOF
+
+# Attempt to schedule an event.
+
+"$OUTGOING_SCRIPT" $ARGS < "$TEMPLATES/event-request-sauna-acl.txt" 2>> $ERROR
+
+   grep -q "^20141126T160000Z${TAB}20141126T164500Z" "$FBSENDERFILE" \
+&& echo "Success" \
+|| echo "Failed"
+
+# Present the request to the resource.
+
+  "$RESOURCE_SCRIPT" $ARGS < "$TEMPLATES/event-request-sauna-acl.txt" 2>> $ERROR \
+| tee out4r.tmp \
+| "$SHOWMAIL" \
+> out4.tmp
+
+   grep -q 'METHOD:REPLY' out4.tmp \
+&& grep -q 'ATTENDEE.*;PARTSTAT=DECLINED' out4.tmp \
+&& echo "Success" \
+|| echo "Failed"
+
+   ! [ -e "$FBFILE" ] \
+|| ! grep -q "^20141126T160000Z${TAB}20141126T164500Z" "$FBFILE" \
+&& echo "Success" \
+|| echo "Failed"
+
+# Try with an unreasonable ACL.
+
+cat > "$ACL" <<EOF
+decline
+EOF
+
+# Attempt to schedule an event.
+
+"$OUTGOING_SCRIPT" $ARGS < "$TEMPLATES/event-request-sauna-acl.txt" 2>> $ERROR
+
+   grep -q "^20141126T160000Z${TAB}20141126T164500Z" "$FBSENDERFILE" \
+&& echo "Success" \
+|| echo "Failed"
+
+# Present the request to the resource.
+
+  "$RESOURCE_SCRIPT" $ARGS < "$TEMPLATES/event-request-sauna-acl.txt" 2>> $ERROR \
+| tee out5r.tmp \
+| "$SHOWMAIL" \
+> out5.tmp
+
+   grep -q 'METHOD:REPLY' out5.tmp \
+&& grep -q 'ATTENDEE.*;PARTSTAT=DECLINED' out5.tmp \
+&& echo "Success" \
+|| echo "Failed"
+
+   ! [ -e "$FBFILE" ] \
+|| ! grep -q "^20141126T160000Z${TAB}20141126T164500Z" "$FBFILE" \
+&& echo "Success" \
+|| echo "Failed"
+
+# Try with a reasonable ACL.
+
+cat > "$ACL" <<EOF
+accept
+decline attendee simon.skunk@example.com
+EOF
+
+# Attempt to schedule an event.
+
+"$OUTGOING_SCRIPT" $ARGS < "$TEMPLATES/event-request-sauna-acl.txt" 2>> $ERROR
+
+   grep -q "^20141126T160000Z${TAB}20141126T164500Z" "$FBSENDERFILE" \
+&& echo "Success" \
+|| echo "Failed"
+
+# Present the request to the resource.
+
+  "$RESOURCE_SCRIPT" $ARGS < "$TEMPLATES/event-request-sauna-acl.txt" 2>> $ERROR \
+| tee out6r.tmp \
+| "$SHOWMAIL" \
+> out6.tmp
+
+   grep -q 'METHOD:REPLY' out6.tmp \
+&& grep -q 'ATTENDEE.*;PARTSTAT=DECLINED' out6.tmp \
+&& echo "Success" \
+|| echo "Failed"
+
+   ! [ -e "$FBFILE" ] \
+|| ! grep -q "^20141126T160000Z${TAB}20141126T164500Z" "$FBFILE" \
+&& echo "Success" \
+|| echo "Failed"
+
+# Modify the ACL, using the implicit preference setting to hold the list.
+
+cat > "$PREFS/$USER/scheduling_function" <<EOF
+schedule_in_freebusy
+access_control_list
+EOF
+
+cat > "$PREFS/$USER/acl" <<EOF
+accept
+decline attendee simon.skunk@example.com
+accept organiser mailto:paul.boddie@example.com
+EOF
+
+# Present the request to the resource.
+
+  "$RESOURCE_SCRIPT" $ARGS < "$TEMPLATES/event-request-sauna-acl.txt" 2>> $ERROR \
+| tee out7r.tmp \
+| "$SHOWMAIL" \
+> out7.tmp
+
+   grep -q 'METHOD:REPLY' out7.tmp \
+&& grep -q 'ATTENDEE.*;PARTSTAT=ACCEPTED' out7.tmp \
+&& echo "Success" \
+|| echo "Failed"
+
+   ! [ -e "$FBFILE" ] \
+|| grep -q "^20141126T160000Z${TAB}20141126T164500Z" "$FBFILE" \
+&& echo "Success" \
+|| echo "Failed"
+
+rm "$ACL"