core/storagemanager.lua

   1
   2 local type, pairs = type, pairs;
   3 local setmetatable = setmetatable;
   4
   5 local config = require "core.configmanager";
   6 local datamanager = require "util.datamanager";
   7 local modulemanager = require "core.modulemanager";
   8 local multitable = require "util.multitable";
   9 local hosts = hosts;
  10 local log = require "util.logger".init("storagemanager");
  11
  12 local prosody = prosody;
  13
  14 local _ENV = nil;
  15
  16 local olddm = {}; -- maintain old datamanager, for backwards compatibility
  17 for k,v in pairs(datamanager) do olddm[k] = v; end
  18
  19 local null_storage_method = function () return false, "no data storage active"; end
  20 local null_storage_driver = setmetatable(
  21         {
  22                 name = "null",
  23                 open = function (self) return self; end
  24         }, {
  25                 __index = function (self, method) --luacheck: ignore 212
  26                         return null_storage_method;
  27                 end
  28         }
  29 );
  30
  31 local stores_available = multitable.new();
  32
  33 local function initialize_host(host)
  34         local host_session = hosts[host];
  35         host_session.events.add_handler("item-added/storage-provider", function (event)
  36                 local item = event.item;
  37                 stores_available:set(host, item.name, item);
  38         end);
  39
  40         host_session.events.add_handler("item-removed/storage-provider", function (event)
  41                 local item = event.item;
  42                 stores_available:set(host, item.name, nil);
  43         end);
  44 end
  45 prosody.events.add_handler("host-activated", initialize_host, 101);
  46
  47 local function load_driver(host, driver_name)
  48         if driver_name == "null" then
  49                 return null_storage_driver;
  50         end
  51         local driver = stores_available:get(host, driver_name);
  52         if driver then return driver; end
  53         local ok, err = modulemanager.load(host, "storage_"..driver_name);
  54         if not ok then
  55                 log("error", "Failed to load storage driver plugin %s on %s: %s", driver_name, host, err);
  56         end
  57         return stores_available:get(host, driver_name);
  58 end
  59
  60 local function get_storage_config(host)
  61         return config.get(host, "storage");
  62 end
  63
  64 local function get_driver(host, store)
  65         local storage = get_storage_config(host);
  66         local driver_name;
  67         local option_type = type(storage);
  68         if option_type == "string" then
  69                 driver_name = storage;
  70         elseif option_type == "table" then
  71                 driver_name = storage[store];
  72         end
  73         if not driver_name then
  74                 driver_name = config.get(host, "default_storage") or "internal";
  75         end
  76
  77         local driver = load_driver(host, driver_name);
  78         if not driver then
  79                 log("warn", "Falling back to null driver for %s storage on %s", store, host);
  80                 driver_name = "null";
  81                 driver = null_storage_driver;
  82         end
  83         return driver, driver_name;
  84 end
  85
  86 local function open(host, store, typ)
  87         local driver, driver_name = get_driver(host, store);
  88         local ret, err = driver:open(store, typ);
  89         if not ret then
  90                 if err == "unsupported-store" then
  91                         log("debug", "Storage driver %s does not support store %s (%s), falling back to null driver",
  92                                 driver_name, store, typ or "<nil>");
  93                         ret = null_storage_driver;
  94                         err = nil;
  95                 end
  96         end
  97         return ret, err;
  98 end
  99
 100 local function purge(user, host)
 101         local storage = get_storage_config(host);
 102         if type(storage) == "table" then
 103                 -- multiple storage backends in use that we need to purge
 104                 local purged = {};
 105                 for store, driver_name in pairs(storage) do
 106                         if not purged[driver_name] then
 107                                 local driver = get_driver(host, store);
 108                                 if driver.purge then
 109                                         purged[driver_name] = driver:purge(user);
 110                                 else
 111                                         log("warn", "Storage driver %s does not support removing all user data, you may need to delete it manually", driver_name);
 112                                 end
 113                         end
 114                 end
 115         end
 116         get_driver(host):purge(user); -- and the default driver
 117
 118         olddm.purge(user, host); -- COMPAT list stores, like offline messages end up in the old datamanager
 119
 120         return true;
 121 end
 122
 123 function datamanager.load(username, host, datastore)
 124         return open(host, datastore):get(username);
 125 end
 126 function datamanager.store(username, host, datastore, data)
 127         return open(host, datastore):set(username, data);
 128 end
 129 function datamanager.users(host, datastore, typ)
 130         local driver = open(host, datastore, typ);
 131         if not driver.users then
 132                 return function() log("warn", "storage driver %s does not support listing users", driver.name) end
 133         end
 134         return driver:users();
 135 end
 136 function datamanager.stores(username, host, typ)
 137         return get_driver(host):stores(username, typ);
 138 end
 139 function datamanager.purge(username, host)
 140         return purge(username, host);
 141 end
 142
 143 return {
 144         initialize_host = initialize_host;
 145         load_driver = load_driver;
 146         get_driver = get_driver;
 147         open = open;
 148         purge = purge;
 149
 150         olddm = olddm;
 151 };