annotate mod_muc_markers/mod_muc_markers.lua @ 5489:a7188eb4ded4

mod_http_debug: Add a brief README
author Kim Alvefur <zash@zash.se>
date Fri, 26 May 2023 15:20:04 +0200
parents 6c57b9e31586
children
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1 -- Track messages received by users of the MUC
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2
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3 -- We rewrite the 'id' attribute of outgoing stanzas to match the stanza (archive) id
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4 -- This module is therefore incompatible with the muc#stable_id feature
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5 -- We rewrite the id because XEP-0333 doesn't tell clients explicitly which id to use
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6 -- in marker reports. However it implies the 'id' attribute through examples, and this
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7 -- is what some clients implement.
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8 -- Notably Conversations will ack the origin-id instead. We need to update the XEP to
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9 -- clarify the correct behaviour.
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11 local set = require "util.set";
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12 local st = require "util.stanza";
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13
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14 local xmlns_markers = "urn:xmpp:chat-markers:0";
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16 local marker_order = { "received", "displayed", "acknowledged" };
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17
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18 -- Add reverse mapping
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19 for priority, name in ipairs(marker_order) do
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20 marker_order[name] = priority;
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21 end
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22
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23 local marker_element_name = module:get_option_string("muc_marker_type", "displayed");
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24 local marker_summary_on_join = module:get_option_boolean("muc_marker_summary_on_join", true);
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25 local rewrite_id_attribute = module:get_option_boolean("muc_marker_rewrite_id", false);
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27 assert(marker_order[marker_element_name], "invalid marker name: "..marker_element_name);
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28
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29 local marker_element_names = set.new();
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30
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31 -- "displayed" implies "received", etc. so we'll add the
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32 -- chosen marker and any "higher" ones to the set
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33 for i = marker_order[marker_element_name], #marker_order do
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34 marker_element_names:add(marker_order[i]);
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35 end
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36
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37 local muc_marker_map_store = module:open_store("muc_markers", "map");
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38
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39 local function get_stanza_id(stanza, by_jid)
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40 for tag in stanza:childtags("stanza-id", "urn:xmpp:sid:0") do
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41 if tag.attr.by == by_jid then
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42 return tag.attr.id;
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43 end
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44 end
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45 return nil;
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46 end
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47
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48 module:hook("muc-broadcast-message", function (event)
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49 local stanza = event.stanza;
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50
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51 local archive_id = get_stanza_id(stanza, event.room.jid);
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52 -- We are not interested in stanzas that didn't get archived
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53 if not archive_id then return; end
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54
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55 if rewrite_id_attribute then
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56 -- Add stanza id as id attribute
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57 stanza.attr.id = archive_id;
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58 end
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59
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60 -- Add markable element to request markers from clients
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61 stanza:tag("markable", { xmlns = xmlns_markers }):up();
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62 end, -1);
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63
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64 module:hook("muc-occupant-groupchat", function (event)
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65 local marker = event.stanza:child_with_ns(xmlns_markers);
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66 if not marker or not marker_element_names:contains(marker.name) then
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67 return; -- No marker, or not one we are interested in
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68 end
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69
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70 -- Store the id that the user has received to
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71 module:log("warn", "New marker for %s in %s: %s", event.occupant.bare_jid, event.room.jid, marker.attr.id);
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72 muc_marker_map_store:set(event.occupant.bare_jid, event.room.jid, marker.attr.id);
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73
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74 end);
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75
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76 module:hook("muc-message-is-historic", function (event)
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77 local marker = event.stanza:get_child(nil, xmlns_markers);
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78
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79 if marker and marker.name ~= "markable" then
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80 -- Prevent stanza from reaching the archive (it's just noise)
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81 return false;
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82 end
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83 end);
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84
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85 local function find_nickname(room, user_jid)
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86 -- Find their current nickname
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87 for nick, occupant in pairs(room._occupants) do
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88 if occupant.bare_jid == user_jid then
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89 return nick;
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90 end
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91 end
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92 -- Or if they're not here
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93 local nickname = room:get_affiliation_data(user_jid, "reserved_nickname");
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94 if nickname then return room.jid.."/"..nickname; end
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95 end
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96
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97 -- Synthesize markers
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98 if muc_marker_map_store.get_all then
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99 module:hook("muc-occupant-session-new", function (event)
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100 if not marker_summary_on_join then
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101 return;
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102 end
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103 local room, to = event.room, event.stanza.attr.from;
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104 local markers = muc_marker_map_store:get_all(room.jid);
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105 if not markers then return end
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106 for user_jid, id in pairs(markers) do
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107 local room_nick = find_nickname(room, user_jid);
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108 if room_nick then
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109 local recv_marker = st.message({ type = "groupchat", from = room_nick, to = to })
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110 :tag(marker_element_name, { xmlns = xmlns_markers, id = id });
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111 room:route_stanza(recv_marker);
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112 end
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113 end
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114 end);
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115 end
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116
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117 -- Public API
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118 --luacheck: ignore 131
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119
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120 function get_user_read_marker(user_jid, room_jid)
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121 return muc_marker_map_store:get(user_jid, room_jid);
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122 end
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123
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124 function is_markable(stanza)
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125 return not not stanza:get_child("markable", xmlns_markers);
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126 end