mod_http: Allow disabling CORS in the http_cors_override option and by default
Fixes #1779.
Due to an oversight in the logic, if the user set 'enabled' to false in an
override, it would disable the item's requested CORS settings, but still apply
Prosody's default CORS policy.
This change ensures that 'enabled = false' will now disable CORS entirely for
the requested item.
Due to the new structure of the code, it was necessary to have a flag to say
whether CORS is to be applied at all. Rather than hard-coding 'true' here, I
chose to add a new option: 'http_default_cors_enabled'. This is a boolean that
allows the operator to disable Prosody's default CORS policy entirely (the one
that is used when a module or config does not override it). This makes it
easier to disable CORS and then selectively enable it only on services you
want it on.
local s_gsub = string.gsub;
local s_match = string.match;
local s_sub = string.sub;
local t_concat = table.concat;
local st = require("util.stanza");
local function render(template, root, escape, filters)
escape = escape or st.xml_escape;
return (s_gsub(template, "%b{}", function(block)
local inner = s_sub(block, 2, -2);
local path, pipe, pos = s_match(inner, "^([^|]+)(|?)()");
if not (type(path) == "string") then return end
local value
if path == "." then
value = root;
elseif path == "#" then
value = root:get_text();
else
value = root:find(path);
end
local is_escaped = false;
while pipe == "|" do
local func, args, tmpl, p = s_match(inner, "^(%w+)(%b())(%b{})()", pos);
if not func then func, args, p = s_match(inner, "^(%w+)(%b())()", pos); end
if not func then func, tmpl, p = s_match(inner, "^(%w+)(%b{})()", pos); end
if not func then func, p = s_match(inner, "^(%w+)()", pos); end
if not func then break end
if tmpl then tmpl = s_sub(tmpl, 2, -2); end
if args then args = s_sub(args, 2, -2); end
if func == "each" and tmpl and st.is_stanza(value) then
if not args then value, args = root, path; end
local ns, name = s_match(args, "^(%b{})(.*)$");
if ns then
ns = s_sub(ns, 2, -2);
else
name, ns = args, nil;
end
if ns == "" then ns = nil; end
if name == "" then name = nil; end
local out, i = {}, 1;
for c in (value):childtags(name, ns) do out[i], i = render(tmpl, c, escape, filters), i + 1; end
value = t_concat(out);
is_escaped = true;
elseif func == "and" and tmpl then
local condition = value;
if args then condition = root:find(args); end
if condition then
value = render(tmpl, root, escape, filters);
is_escaped = true;
end
elseif func == "or" and tmpl then
local condition = value;
if args then condition = root:find(args); end
if not condition then
value = render(tmpl, root, escape, filters);
is_escaped = true;
end
elseif filters and filters[func] then
local f = filters[func];
if args == nil then
value, is_escaped = f(value, tmpl);
else
value, is_escaped = f(args, value, tmpl);
end
else
error("No such filter function: " .. func);
end
pipe, pos = s_match(inner, "^(|?)()", p);
end
if type(value) == "string" then
if not is_escaped then value = escape(value); end
return value
elseif st.is_stanza(value) then
value = value:get_text();
if value then return escape(value) end
end
return ""
end))
end
return { render = render }