cfg: allow uri of any type, not only string

Since 2.10.0-beta2 URI in all APIs can be passed not only as a
string or number but also as a table.

The table can be used to pass options like transport type (plain,
SSL), encryption certificate and key, and potentially more.

VShard always supported only string URIs but now it allows numbers
and tables as well. In the config the replica_object.uri field is
affected by the change.

Part of #325

test/unit-luatest/config_test.lua

@@ -0,0 +1,44 @@
+local t = require('luatest')
+local lcfg = require('vshard.cfg')
+local uuid = require('uuid')
+
+local g = t.group('config')
+
+g.test_basic_uri = function()
+    local url = 'storage:storage@127.0.0.1:3301'
+    local storage_1_a = {
+        uri = url,
+        name = 'storage_1_a',
+    }
+    local config = {
+        sharding = {
+            storage_1_uuid = {
+                replicas = {
+                    storage_1_a_uuid = storage_1_a,
+                }
+            },
+        },
+    }
+    t.assert(lcfg.check(config), 'normal uri')
+
+    storage_1_a.uri = {url}
+    t.assert(lcfg.check(config), 'table uri')
+
+    storage_1_a.uri = {url, params = {transport = 'plain'}}
+    t.assert(lcfg.check(config), 'uri with options')
+
+    storage_1_a.uri = 3301
+    t.assert(lcfg.check(config), 'number uri')
+
+    storage_1_a.uri = 'bad uri ###'
+    t.assert_error(lcfg.check, config)
+
+    storage_1_a.uri = {}
+    t.assert_error(lcfg.check, config)
+
+    storage_1_a.uri = nil
+    t.assert_error(lcfg.check, config)
+
+    storage_1_a.uri = uuid.new()
+    t.assert_error(lcfg.check, config)
+end

test/unit/config.result

@@ -45,12 +45,12 @@ check(cfg)
 ---
 - URI must be specified
 ...
-replica.uri = 100
+replica.uri = {}
 ---
 ...
 check(cfg)
 ---
-- URI must be non-empty string
+- URI must be a non-empty string, or a number, or a table
 ...
 replica.uri = 'uri:uri@uri'
 ---
@@ -467,7 +467,7 @@ replica.uri = 'invalid uri'
 ...
 util.check_error(lcfg.check, cfg)
 ---
-- 'Invalid URI: invalid uri'
+- URI must be a non-empty string, or a number, or a table
 ...
 replica.uri = '127.0.0.1'
 ---

test/unit/config.test.lua

@@ -24,7 +24,7 @@ cfg = {sharding = {['replicaset_uuid'] = replicaset}}
 
 -- URI is not string.
 check(cfg)
-replica.uri = 100
+replica.uri = {}
 check(cfg)
 replica.uri = 'uri:uri@uri'
 

vshard/cfg.lua

@@ -6,7 +6,7 @@ local consts = require('vshard.consts')
 
 local function check_uri(uri)
     if not luri.parse(uri) then
-        error('Invalid URI: ' .. uri)
+        error('URI must be a non-empty string, or a number, or a table')
     end
 end
 
@@ -113,7 +113,11 @@ local function validate_config(config, template, check_arg)
 end
 
 local replica_template = {
-    uri = {type = 'non-empty string', name = 'URI', check = check_uri},
+    uri = {
+        type = {'non-empty string', 'number', 'table'},
+        name = 'URI',
+        check = check_uri
+    },
     name = {type = 'string', name = "Name", is_optional = true},
     zone = {type = {'string', 'number'}, name = "Zone", is_optional = true},
     master = {