1. -- mod_http_upload_external
2. --
3. -- Copyright (C) 2016 Sebastian Luksch
4. --
5. -- This file is MIT/X11 licensed.
6. --
7. -- Implementation of HTTP Upload file transfer mechanism used by Conversations
8. --
9. -- Query external HTTP server to retrieve URLs
10. --
11.  
12. -- configuration
13. local external_url = "https://snippets.thedevstack.de/httpupload/index.php";
14. local xmpp_server_key = "1323978hjkgh12";
15.  
16. -- imports
17. local st = require"util.stanza";
18. local http = require"socket.http";
19. local json = require"util.json";
20.  
21. -- depends
22. module:depends("disco");
23.  
24. -- namespace
25. local xmlns_http_upload = "urn:xmpp:http:upload";
26.  
27. module:add_feature(xmlns_http_upload);
28.  
29. -- hooks
30. module:hook("iq/host/"..xmlns_http_upload..":request", function (event)
31.    local stanza, origin = event.stanza, event.origin;
32.    local orig_from = stanza.attr.from;
33.    local request = stanza.tags[1];
34.    -- local clients only
35.    if origin.type ~= "c2s" then
36.       origin.send(st.error_reply(stanza, "cancel", "not-authorized"));
37.       return true;
38.    end
39.    -- validate
40.    local filename = request:get_child_text("filename");
41.    if not filename then
42.       origin.send(st.error_reply(stanza, "modify", "bad-request", "Invalid filename"));
43.       return true;
44.    end
45.    local filesize = tonumber(request:get_child_text("size"));
46.    if not filesize then
47.       origin.send(st.error_reply(stanza, "modify", "bad-request", "Missing or invalid file size"));
48.       return true;
49.    end
50.  
51.    local content_type = request:get_child_text("content-type");
52.    
53.    -- build the body
54.    local reqbody = "xmpp_server_key=" .. xmpp_server_key .. "&size=" .. filesize .. "&filename=" .. filename .. "&user_jid=" .. orig_from;
55.    if content_type then
56.       reqbody = reqbody .. "&content_type=" .. content_type;
57.    end
58.  
59.    -- the request
60.    local respbody, statuscode = http.request(external_url, reqbody);
61.    respbody = string.gsub(respbody, "\\/", "/")
62.  
63.    local get_url = nil;
64.    local put_url = nil;
65.  
66.    -- check the response
67.    if statuscode == 500 then
68.       origin.send(st.error_reply(stanza, "cancel", "service-unavailable", respbody));
69.    elseif statuscode == 406 or statuscode == 400 or statuscode == 403 then
70.       local errobj, pos, err = json.decode(respbody);
71.       if err then
72.          origin.send(st.error_reply(stanza, "wait", "internal-server-error", err));
73.          return true;
74.       else
75.          if errobj["err_code"] ~= nil and errobj["msg"] ~= nil then
76.             if errobj.err_code == 1 then
77.                origin.send(st.error_reply(stanza, "modify", "not-acceptable", errobj.msg));
78.                return true;
79.             elseif errobj.err_code == 2 then
80.                origin.send(st.error_reply(stanza, "modify", "not-acceptable", errobj.msg,
81.                   st.stanza("file-too-large", {xmlns=xmlns_http_upload})
82.                      :tag("max-size"):text(errobj.parameters.max_file_size)));
83.                return true;
84.             elseif errobj.err_code == 3 then
85.                origin.send(st.error_reply(stanza, "modify", "not-acceptable", errobj.msg,
86.                   st.stanza("invalid-character", {xmlns=xmlns_http_upload})
87.                      :text(errobj.parameters.invalid_character)));
88.                return true;
89.             elseif errobj.err_code == 4 then
90.                origin.send(st.error_reply(stanza, "cancel", "internal-server-error", errobj.msg,
91.                   st.stanza("missing-parameter", {xmlns=xmlns_http_upload})
92.                      :text(errobj.parameters.missing_parameter)));
93.                return true;
94.             else
95.                origin.send(st.error_reply(stanza, "cancel", "undefined-condition", "unknown err_code"));
96.                return true;
97.             end
98.          elseif statuscode == 403 and errobj["msg"] ~= nil then
99.             origin.send(st.error_reply(stanza, "cancel", "internal-server-error", errobj.msg));
100.          else
101.             origin.send(st.error_reply(stanza, "cancel", "undefined-condition", "msg or err_code not found"));
102.             return true;
103.          end
104.       end
105.    elseif statuscode == 200 then
106.       local respobj, pos, err = json.decode(respbody);
107.       if err then
108.          origin.send(st.error_reply(stanza, "wait", "internal-server-error", err));
109.          return true;
110.       else
111.          if respobj["get"] ~= nil and respobj["put"] ~= nil then
112.             get_url = respobj.get;
113.             put_url = respobj.put;
114.          else
115.             origin.send(st.error_reply(stanza, "cancel", "undefined-condition", "get or put not found"));
116.             return true;
117.          end
118.       end
119.    else
120.       origin.send(st.error_reply(stanza, "cancel", "undefined-condition", "status code: " .. statuscode .. " response: " ..respbody));
121.       return true;
122.    end
123.  
124.    local reply = st.reply(stanza);
125.    reply:tag("slot", { xmlns = xmlns_http_upload });
126.    reply:tag("get"):text(get_url):up();
127.    reply:tag("put"):text(put_url):up();
128.    origin.send(reply);
129.    return true;
130. end);
131.