mod_pep: Wipe pubsub service on user deletion
Data is already wiped from storage, but this ensures everything is
properly unsubscribed, possibly with notifications etc.
Clears recipient cache as well, since it is no longer relevant.
local promise_methods = {};
local promise_mt = { __name = "promise", __index = promise_methods };
local xpcall = require "util.xpcall".xpcall;
function promise_mt:__tostring()
return "promise (" .. (self._state or "invalid") .. ")";
end
local function is_promise(o)
local mt = getmetatable(o);
return mt == promise_mt;
end
local function wrap_handler(f, resolve, reject, default)
if not f then
return default;
end
return function (param)
local ok, ret = xpcall(f, debug.traceback, param);
if ok then
resolve(ret);
else
reject(ret);
end
return true;
end;
end
local function next_pending(self, on_fulfilled, on_rejected, resolve, reject)
table.insert(self._pending_on_fulfilled, wrap_handler(on_fulfilled, resolve, reject, resolve));
table.insert(self._pending_on_rejected, wrap_handler(on_rejected, resolve, reject, reject));
end
local function next_fulfilled(promise, on_fulfilled, on_rejected, resolve, reject) -- luacheck: ignore 212/on_rejected
wrap_handler(on_fulfilled, resolve, reject, resolve)(promise.value);
end
local function next_rejected(promise, on_fulfilled, on_rejected, resolve, reject) -- luacheck: ignore 212/on_fulfilled
wrap_handler(on_rejected, resolve, reject, reject)(promise.reason);
end
local function promise_settle(promise, new_state, new_next, cbs, value)
if promise._state ~= "pending" then
return;
end
promise._state = new_state;
promise._next = new_next;
for _, cb in ipairs(cbs) do
cb(value);
end
return true;
end
local function new_resolve_functions(p)
local resolved = false;
local function _resolve(v)
if resolved then return; end
resolved = true;
if is_promise(v) then
v:next(new_resolve_functions(p));
elseif promise_settle(p, "fulfilled", next_fulfilled, p._pending_on_fulfilled, v) then
p.value = v;
end
end
local function _reject(e)
if resolved then return; end
resolved = true;
if promise_settle(p, "rejected", next_rejected, p._pending_on_rejected, e) then
p.reason = e;
end
end
return _resolve, _reject;
end
local function new(f)
local p = setmetatable({ _state = "pending", _next = next_pending, _pending_on_fulfilled = {}, _pending_on_rejected = {} }, promise_mt);
if f then
local resolve, reject = new_resolve_functions(p);
local ok, ret = xpcall(f, debug.traceback, resolve, reject);
if not ok and p._state == "pending" then
reject(ret);
end
end
return p;
end
local function all(promises)
return new(function (resolve, reject)
local count, total, results = 0, #promises, {};
for i = 1, total do
promises[i]:next(function (v)
results[i] = v;
count = count + 1;
if count == total then
resolve(results);
end
end, reject);
end
end);
end
local function race(promises)
return new(function (resolve, reject)
for i = 1, #promises do
promises[i]:next(resolve, reject);
end
end);
end
local function resolve(v)
return new(function (_resolve)
_resolve(v);
end);
end
local function reject(v)
return new(function (_, _reject)
_reject(v);
end);
end
local function try(f)
return resolve():next(function () return f(); end);
end
function promise_methods:next(on_fulfilled, on_rejected)
return new(function (resolve, reject) --luacheck: ignore 431/resolve 431/reject
self:_next(on_fulfilled, on_rejected, resolve, reject);
end);
end
function promise_methods:catch(on_rejected)
return self:next(nil, on_rejected);
end
function promise_methods:finally(on_finally)
local function _on_finally(value) on_finally(); return value; end
local function _on_catch_finally(err) on_finally(); return reject(err); end
return self:next(_on_finally, _on_catch_finally);
end
return {
new = new;
resolve = resolve;
reject = reject;
all = all;
race = race;
try = try;
is_promise = is_promise;
}