Mercurial > prosody-modules

comparison mod_bob/mod_bob.lua @ 3342:3aa5419e3576

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
mod_bob: Add this new module.
author Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
date Fri, 28 Sep 2018 16:12:18 +0200
parents
children 2e65160187a4
comparison
equal deleted inserted replaced
3341:1e1dbd7e5b6c 3342:3aa5419e3576
1 module:depends("cache_c2s_caps");
2
3 local st = require "util.stanza";
4 local encodings = require "util.encodings";
5 local b64_encode = encodings.base64.encode;
6 local b64_decode = encodings.base64.decode;
7 local sha1 = require"util.hashes".sha1;
8
9 -- TODO: Move that to storage.
10 local cache = {};
11 -- TODO: use util.cache for this.
12 local in_flight = {};
13
14 local function check_cid(src)
15 -- TODO: figure out why ^ can’t be used at the beginning of the pattern.
16 for cid in src:gmatch("cid:(%w+%+%w+@bob%.xmpp%.org)$") do
17 return cid;
18 end
19 return nil;
20 end
21
22 local function handle_data_carrier(tag)
23 if tag.name ~= "data" or tag.attr.xmlns ~= "urn:xmpp:bob" then
24 return tag;
25 end
26 local cid = tag.attr.cid;
27 local media_type = tag.attr.type;
28 local max_age = tag.attr['max-age'];
29 local b64_content = tag:get_text();
30 local content = b64_decode(b64_content);
31 local hash = sha1(content, true);
32 if cid ~= "sha1+"..hash.."@bob.xmpp.org" then
33 module:log("debug", "Invalid BoB cid, %s ~= %s", cid, "sha1+"..hash.."@bob.xmpp.org");
34 return nil;
35 end
36 cache[cid] = { media_type = media_type, max_age = max_age, content = content };
37 if in_flight[cid] then
38 local iq = st.iq({ type = "result", id = "fixme" });
39 iq:add_direct_child(tag);
40 for jid, data in pairs(in_flight[cid]) do
41 iq.attr.from = data.from;
42 iq.attr.to = jid;
43 iq.attr.id = data.id;
44 module:send(iq);
45 end
46 in_flight[cid] = nil;
47 end
48 return nil;
49 end
50
51 local current_id = 0;
52 local function send_iq(room_jid, jid, cid, log)
53 local iq = st.iq({ type = "get", from = room_jid, to = jid, id = "bob-"..current_id })
54 :tag("data", { xmlns = "urn:xmpp:bob", cid = cid });
55 log("debug", "found BoB image in XHTML-IM, asking %s for cid %s", jid, cid);
56 module:send(iq);
57 in_flight[cid] = {};
58 end
59
60 local function find_images(tag, jid, room_jid, log)
61 if tag.name == "img" and tag.attr.xmlns == "http://www.w3.org/1999/xhtml" then
62 local src = tag.attr.src;
63 local cid = check_cid(src);
64 if not cid then
65 return;
66 end
67 if cache[cid] then
68 log("debug", "cid %s already found in cache", cid);
69 return;
70 end
71 if in_flight[cid] then
72 log("debug", "cid %s already queried", cid);
73 return;
74 end
75 send_iq(room_jid, jid, cid, log);
76 return;
77 end
78 for child in tag:childtags(nil, "http://www.w3.org/1999/xhtml") do
79 find_images(child, jid, room_jid, log);
80 end
81 end
82
83 local function message_handler(event)
84 local stanza, origin = event.stanza, event.origin;
85 local jid = stanza.attr.from;
86 local room_jid = stanza.attr.to;
87 local log = origin.log or module._log;
88
89 -- Remove and cache all <data/> elements embedded here.
90 stanza:maptags(handle_data_carrier);
91
92 -- Find and query all of the cids not already cached.
93 local tag = stanza:get_child("html", "http://jabber.org/protocol/xhtml-im");
94 for body in tag:childtags("body", "http://www.w3.org/1999/xhtml") do
95 find_images(body, jid, room_jid, log);
96 end
97 end
98
99 local function handle_data_get(stanza, cid, log)
100 local data = cache[cid];
101 if not data then
102 log("debug", "BoB requested for data not in cache (cid %s), falling through.", cid);
103 if in_flight[cid] then
104 log("debug", "But an iq has already been sent, let’s wait…");
105 in_flight[cid][stanza.attr.from] = { id = stanza.attr.id, from = stanza.attr.to };
106 return true;
107 end
108 return nil;
109 end
110
111 local iq = st.reply(stanza);
112 iq:text_tag("data", b64_encode(data.content), {
113 xmlns = "urn:xmpp:bob",
114 cid = cid,
115 type = data.media_type,
116 ['max-age'] = data.max_age,
117 });
118 log("debug", "Answering BoB request for cid %s on the behalf of %s", cid, stanza.attr.to);
119 module:send(iq);
120 return true;
121 end
122
123 local function iq_handler(event)
124 local stanza, origin = event.stanza, event.origin;
125 local tag = stanza.tags[1];
126 if tag.name ~= "data" or tag.attr.xmlns ~= "urn:xmpp:bob" then
127 return nil;
128 end
129 local log = origin.log or module._log;
130 local cid = tag.attr.cid;
131 if not cid then
132 log("debug", "BoB iq doesn’t contain a cid attribute.");
133 return;
134 end
135 if stanza.attr.type == "get" then
136 return handle_data_get(stanza, cid, log);
137 elseif stanza.attr.type == "result" then
138 handle_data_carrier(tag);
139 return true;
140 end
141 -- TODO: also handle error iqs.
142 end
143
144 module:hook("message/bare", message_handler, 1);
145 module:hook("iq/full", iq_handler, 1);
146 module:hook("iq/bare", iq_handler, 1);