storage: introduce name identification

This commit allows storage to use named config identification.

Part of tarantool#426

@TarantoolBot document
Title: vshard: vshard.storage.cfg argument change

vshard.storage.cfg(cfg, instance_id)

Configure the database and start sharding for the specified storage
instance. `istance_id` depends on `identification_mode` used in config.
If it's 'uuid_as_key', which is default, then UUID must be used.
Otherwise - instance_name.

Parameters:
    cfg – a storage configuration
    instance_id – UUID or name of the instance

test/storage-luatest/storage_1_1_test.lua

@@ -530,3 +530,63 @@ test_group.test_noactivity_timeout_for_explicit_master = function(g)
         _G.bucket_gc_wait()
     end, {g.replica_1_a:replicaset_uuid(), bid})
 end
+
+test_group.test_named_config_identification = function(g)
+    t.run_only_if(vutil.version_is_at_least(3, 0, 0, 'entrypoint', 0, 0))
+    local new_cfg_template = table.deepcopy(cfg_template)
+    new_cfg_template.identification_mode = 'name_as_key'
+    new_cfg_template.sharding['replicaset_1'] = new_cfg_template.sharding[1]
+    new_cfg_template.sharding['replicaset_2'] = new_cfg_template.sharding[2]
+    new_cfg_template.sharding[1] = nil
+    new_cfg_template.sharding[2] = nil
+    local new_global_cfg = vtest.config_new(new_cfg_template)
+
+    -- Attempt to configure with named config without name set causes error.
+    g.replica_1_a:exec(function(cfg)
+        ilt.assert_error_msg_contains('Instance name mismatch',
+                                      ivshard.storage.cfg, cfg, 'replica_1_a')
+    end, {new_global_cfg})
+
+    -- Set names on all replicas.
+    g.replica_1_a:exec(function()
+        box.cfg{instance_name = 'replica_1_a', replicaset_name = 'replicaset_1'}
+    end)
+    g.replica_2_a:exec(function()
+        box.cfg{instance_name = 'replica_2_a', replicaset_name = 'replicaset_2'}
+    end)
+
+    -- Now the config can be finally applied.
+    vtest.cluster_cfg(g, new_global_cfg)
+
+    -- Test, that sending by name works properly
+    local rs_name_2 = g.replica_2_a:replicaset_name()
+    t.assert_equals(rs_name_2, 'replicaset_2')
+    g.replica_1_a:exec(function(name)
+        local bid = _G.get_first_bucket()
+        local ok, err = ivshard.storage.bucket_send(
+            bid, name, {timeout = _G.iwait_timeout})
+        ilt.assert_equals(err, nil)
+        ilt.assert(ok)
+    end, {rs_name_2})
+
+    -- Test, that rebalancer is also ok.
+    vtest.cluster_rebalancer_enable(g)
+    g.replica_1_a:exec(function()
+        local internal = ivshard.storage.internal
+        ivtest.service_wait_for_ok(internal.rebalancer_service,
+            {on_yield = ivshard.storage.rebalancer_wakeup})
+
+        -- Cleanup
+        _G.bucket_recovery_wait()
+        _G.bucket_gc_wait()
+    end)
+
+    g.replica_2_a:exec(function()
+        _G.bucket_recovery_wait()
+        _G.bucket_gc_wait()
+    end)
+
+    vtest.cluster_rebalancer_disable(g)
+    -- Back to UUID identification.
+    vtest.cluster_cfg(g, global_cfg)
+end

test/unit/rebalancer.result

@@ -1078,9 +1078,9 @@ d
   map:
     uuid:
       bucket_count: 0
+      id: uuid
       progress: 0
       is_throttle_warned: false
-      uuid: uuid
       need_to_send: 15
 ...
 d = dispenser.create({uuid1 = 5, uuid2 = 5})
@@ -1099,13 +1099,13 @@ u, d
       prev: &1
         bucket_count: 5
         next: *0
+        id: uuid1
         progress: 0
         is_throttle_warned: false
-        uuid: uuid1
         need_to_send: 5
+      id: uuid2
       progress: 0
       is_throttle_warned: false
-      uuid: uuid2
       need_to_send: 5
     first: *1
   map:
@@ -1124,13 +1124,13 @@ d
       prev: &1
         bucket_count: 5
         next: *0
+        id: uuid1
         progress: 0
         is_throttle_warned: false
-        uuid: uuid1
         need_to_send: 5
+      id: uuid2
       progress: 0
       is_throttle_warned: false
-      uuid: uuid2
       need_to_send: 5
     first: *1
   map:
@@ -1150,13 +1150,13 @@ d
       prev: &1
         bucket_count: 5
         next: *0
+        id: uuid1
         progress: 0
         is_throttle_warned: false
-        uuid: uuid1
         need_to_send: 5
+      id: uuid2
       progress: 0
       is_throttle_warned: true
-      uuid: uuid2
       need_to_send: 5
     first: *1
   map: