Move creating required resources to start funcs

I don't like creating files, directories, whatever at the point of the
'class instance' initialization -- the `new` function. It's more logical
and gently to create all required resources on the start.

Author: ylobankov

luatest/replica_proxy.lua

@@ -4,8 +4,10 @@
 
 local checks = require('checks')
 local fiber = require('fiber')
+local fio = require('fio')
 local log = require('log')
 local socket = require('socket')
+local uri = require('uri')
 
 local utils = require('luatest.utils')
 local Connection = require('luatest.replica_conn')
@@ -98,6 +100,8 @@ function Proxy:start(opts)
         os.remove(self.client_socket_path)
     end
 
+    fio.mktree(fio.dirname(uri.parse(self.client_socket_path).service))
+
     if not self.client_socket:bind('unix/', self.client_socket_path) then
         log.error("Failed to bind client socket: %s", self.client_socket:error())
         return false

luatest/replica_set.lua

@@ -62,7 +62,6 @@ function ReplicaSet:initialize()
     self.alias = 'rs'
     self.id = ('%s-%s'):format(self.alias, utils.generate_id())
     self.workdir = fio.pathjoin(self._server.vardir, self.id)
-    fio.mktree(self.workdir)
 
     if self.servers then
         local configs = table.deepcopy(self.servers)
@@ -162,6 +161,8 @@ end
 function ReplicaSet:start(opts)
     checks('table', {wait_until_ready = '?boolean'})
 
+    fio.mktree(self.workdir)
+
     for _, server in ipairs(self.servers) do
         if not server.process then
             server:start({wait_until_ready = false})

luatest/server.lua

@@ -74,10 +74,10 @@ end
 --   Defaults to 'server'.
 -- @string[opt] object.workdir Working directory for the new server and the
 --   value of the `TARANTOOL_WORKDIR` env variable which is passed into the
---   server process.
+--   server process. The directory path will be created on the server start.
 --   Defaults to `<vardir>/<alias>-<random id>`.
 -- @string[opt] object.datadir Directory path whose contents will be recursively
---   copied into `object.workdir` during initialization.
+--   copied into `object.workdir` on the server start.
 -- @number[opt] object.http_port Port for HTTP connection to the new server and
 --   the value of the `TARANTOOL_HTTP_PORT` env variable which is passed into
 --   the server process.
@@ -87,7 +87,8 @@ end
 --   into the server process.
 -- @string[opt] object.net_box_uri URI for the `net.box` connection to the new
 --   server and the value of the `TARANTOOL_LISTEN` env variable which is passed
---   into the server process.
+--   into the server process. If it is a Unix socket, the corresponding socket
+--   directory path will be created on the server start.
 -- @tab[opt] object.net_box_credentials Override the default credentials for the
 --   `net.box` connection to the new server.
 -- @tab[opt] object.box_cfg Extra options for `box.cfg()` and the value of the
@@ -143,15 +144,6 @@ function Server:initialize()
         self.workdir = fio.pathjoin(self.vardir, self.id)
         fio.rmtree(self.workdir)
     end
-    fio.mktree(self.workdir)
-
-    if self.datadir ~= nil then
-        local ok, err = fio.copytree(self.datadir, self.workdir)
-        if not ok then
-            error(('Failed to copy directory: %s'):format(err))
-        end
-        self.datadir = nil
-    end
 
     if self.http_port then
         self.http_client = http_client.new()
@@ -163,8 +155,7 @@ function Server:initialize()
     if self.net_box_uri == nil and self.net_box_port then
         self.net_box_uri = 'localhost:' .. self.net_box_port
     end
-    local parsed_net_box_uri = uri.parse(self.net_box_uri)
-    if parsed_net_box_uri.host == 'unix/' then
+    if uri.parse(self.net_box_uri).host == 'unix/' then
         -- Linux uses max 108 bytes for Unix domain socket paths, which means a 107 characters
         -- string ended by a null terminator. Other systems use 104 bytes and 103 characters strings.
         local max_unix_socket_path = {linux = 107, other = 103}
@@ -173,7 +164,6 @@ function Server:initialize()
             error(('Net box URI must be <= max Unix domain socket path length (%d chars)')
                 :format(max_unix_socket_path[system]))
         end
-        fio.mktree(fio.dirname(parsed_net_box_uri.service))
     end
 
     self.env = utils.merge(self.env or {}, self:build_env())
@@ -253,6 +243,33 @@ function Server.build_listen_uri(server_alias, extra_path)
     return fio.pathjoin(Server.vardir, extra_path or '', server_alias .. '.sock')
 end
 
+--- Make the server's working directory.
+-- Invoked on the server's start.
+function Server:make_workdir()
+    fio.mktree(self.workdir)
+end
+
+--- Copy contents of the data directory into the server's working directory.
+-- Invoked on the server's start.
+function Server:copy_datadir()
+    if self.datadir ~= nil then
+        local ok, err = fio.copytree(self.datadir, self.workdir)
+        if not ok then
+            error(('Failed to copy %s to %s: %s'):format(self.datadir, self.workdir, err))
+        end
+        self.datadir = nil
+    end
+end
+
+--- Make directory for the server's Unix socket.
+-- Invoked on the server's start.
+function Server:make_socketdir()
+    local parsed_net_box_uri = uri.parse(self.net_box_uri)
+    if parsed_net_box_uri.host == 'unix/' then
+        fio.mktree(fio.dirname(parsed_net_box_uri.service))
+    end
+end
+
 --- Start a server.
 -- Optionally waits until the server is ready.
 --
@@ -265,6 +282,10 @@ function Server:start(opts)
 
     self:initialize()
 
+    self:make_workdir()
+    self:copy_datadir()
+    self:make_socketdir()
+
     local command = self.command
     local args = table.copy(self.args)
     local env = table.copy(os.environ())

test/replica_set_test.lua

@@ -5,26 +5,26 @@ local ReplicaSet = require('luatest.replica_set')
 local g = t.group()
 local Server = t.Server
 
-g.before_all(function()
+g.before_each(function()
+    g.rs = ReplicaSet:new()
     g.box_cfg = {
         replication_timeout = 0.1,
         replication_connect_timeout = 10,
         replication_sync_lag = 0.01,
         replication_connect_quorum = 3,
         replication = {
-            Server.build_listen_uri('replica1'),
-            Server.build_listen_uri('replica2'),
-            Server.build_listen_uri('replica3'),
+            Server.build_listen_uri('replica1', g.rs.id),
+            Server.build_listen_uri('replica2', g.rs.id),
+            Server.build_listen_uri('replica3', g.rs.id),
         }
     }
 end)
 
 g.before_test('test_save_rs_artifacts_when_test_failed', function()
-    g.rs = ReplicaSet:new()
-
     g.rs:build_and_add_server({alias = 'replica1', box_cfg = g.box_cfg})
     g.rs:build_and_add_server({alias = 'replica2', box_cfg = g.box_cfg})
     g.rs:build_and_add_server({alias = 'replica3', box_cfg = g.box_cfg})
+    g.rs:start()
 
     g.rs_artifacts = ('%s/artifacts/%s'):format(Server.vardir, g.rs.id)
     g.s1_artifacts = ('%s/%s'):format(g.rs_artifacts, g.rs:get_server('replica1').id)
@@ -53,15 +53,14 @@ g.test_save_rs_artifacts_when_test_failed = function()
 end
 
 g.before_test('test_save_rs_artifacts_when_server_workdir_passed', function()
-    g.rs = ReplicaSet:new()
-
     local s1_workdir = ('%s/%s'):format(Server.vardir, os.tmpname())
     local s2_workdir = ('%s/%s'):format(Server.vardir, os.tmpname())
     local s3_workdir = ('%s/%s'):format(Server.vardir, os.tmpname())
 
     g.rs:build_and_add_server({workdir = s1_workdir, alias = 'replica1', box_cfg = g.box_cfg})
     g.rs:build_and_add_server({workdir = s2_workdir, alias = 'replica2', box_cfg = g.box_cfg})
     g.rs:build_and_add_server({workdir = s3_workdir, alias = 'replica3', box_cfg = g.box_cfg})
+    g.rs:start()
 
     g.rs_artifacts = ('%s/artifacts/%s'):format(Server.vardir, g.rs.id)
     g.s1_artifacts = ('%s/%s'):format(g.rs_artifacts, g.rs:get_server('replica1').id)
@@ -91,11 +90,10 @@ g.test_save_rs_artifacts_when_server_workdir_passed = function()
 end
 
 g.before_test('test_remove_rs_artifacts_when_test_success', function()
-    g.rs = ReplicaSet:new()
-
     g.rs:build_and_add_server({alias = 'replica1', box_cfg = g.box_cfg})
     g.rs:build_and_add_server({alias = 'replica2', box_cfg = g.box_cfg})
     g.rs:build_and_add_server({alias = 'replica3', box_cfg = g.box_cfg})
+    g.rs:start()
 
     g.rs_artifacts = ('%s/artifacts/%s'):format(Server.vardir, g.rs.id)
     g.s1_artifacts = ('%s/%s'):format(g.rs_artifacts, g.rs:get_server('replica1').id)
@@ -109,10 +107,6 @@ g.test_remove_rs_artifacts_when_test_success = function()
     t.assert_equals(fio.path.exists(g.rs.workdir), false)
 end
 
-g.before_test('test_rs_no_socket_collision_with_custom_alias', function()
-    g.rs = ReplicaSet:new()
-end)
-
 g.test_rs_no_socket_collision_with_custom_alias = function()
     local s1 = g.rs:build_server({alias = 'foo'})
     local s2 = g.rs:build_server({alias = 'bar'})
@@ -127,15 +121,11 @@ g.after_test('test_rs_no_socket_collision_with_custom_alias', function()
     g.rs:drop()
 end)
 
-g.before_test('test_rs_custom_properties_are_not_overridden', function()
-    g.rs = ReplicaSet:new()
-end)
-
 g.test_rs_custom_properties_are_not_overridden = function()
     local socket = ('%s/custom.sock'):format(Server.vardir)
     local workdir = ('%s/custom'):format(Server.vardir)
 
-    local s = g.rs:build_server({net_box_uri = socket, workdir=workdir})
+    local s = g.rs:build_server({net_box_uri = socket, workdir = workdir})
 
     t.assert_equals(s.net_box_uri, socket)
     t.assert_equals(s.workdir, workdir)
@@ -145,10 +135,6 @@ g.after_test('test_rs_custom_properties_are_not_overridden', function()
     g.rs:drop()
 end)
 
-g.before_test('test_rs_raise_error_when_add_custom_server', function()
-    g.rs = ReplicaSet:new()
-end)
-
 g.test_rs_raise_error_when_add_custom_server = function()
     local s = Server:new()