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_driver(host, store)
  61         local storage = config.get(host, "storage");
  62         local driver_name;
  63         local option_type = type(storage);
  64         if option_type == "string" then
  65                 driver_name = storage;
  66         elseif option_type == "table" then
  67                 driver_name = storage[store];
  68         end
  69         if not driver_name then
  70                 driver_name = config.get(host, "default_storage") or "internal";
  71         end
  72
  73         local driver = load_driver(host, driver_name);
  74         if not driver then
  75                 log("warn", "Falling back to null driver for %s storage on %s", store, host);
  76                 driver_name = "null";
  77                 driver = null_storage_driver;
  78         end
  79         return driver, driver_name;
  80 end
  81
  82 local function open(host, store, typ)
  83         local driver, driver_name = get_driver(host, store);
  84         local ret, err = driver:open(store, typ);
  85         if not ret then
  86                 if err == "unsupported-store" then
  87                         log("debug", "Storage driver %s does not support store %s (%s), falling back to null driver",
  88                                 driver_name, store, typ or "<nil>");
  89                         ret = null_storage_driver;
  90                         err = nil;
  91                 end
  92         end
  93         return ret, err;
  94 end
  95
  96 local function purge(user, host)
  97         local storage = config.get(host, "storage");
  98         if type(storage) == "table" then
  99                 -- multiple storage backends in use that we need to purge
 100                 local purged = {};
 101                 for store, driver_name in pairs(storage) do
 102                         if not purged[driver_name] then
 103                                 local driver = get_driver(host, store);
 104                                 if driver.purge then
 105                                         purged[driver_name] = driver:purge(user);
 106                                 else
 107                                         log("warn", "Storage driver %s does not support removing all user data, you may need to delete it manually", driver_name);
 108                                 end
 109                         end
 110                 end
 111         end
 112         get_driver(host):purge(user); -- and the default driver
 113
 114         olddm.purge(user, host); -- COMPAT list stores, like offline messages end up in the old datamanager
 115
 116         return true;
 117 end
 118
 119 function datamanager.load(username, host, datastore)
 120         return open(host, datastore):get(username);
 121 end
 122 function datamanager.store(username, host, datastore, data)
 123         return open(host, datastore):set(username, data);
 124 end
 125 function datamanager.users(host, datastore, typ)
 126         local driver = open(host, datastore, typ);
 127         if not driver.users then
 128                 return function() log("warn", "storage driver %s does not support listing users", driver.name) end
 129         end
 130         return driver:users();
 131 end
 132 function datamanager.stores(username, host, typ)
 133         return get_driver(host):stores(username, typ);
 134 end
 135 function datamanager.purge(username, host)
 136         return purge(username, host);
 137 end
 138
 139 return {
 140         initialize_host = initialize_host;
 141         load_driver = load_driver;
 142         get_driver = get_driver;
 143         open = open;
 144         purge = purge;
 145
 146         olddm = olddm;
 147 };