[tarantool-patches] [PATCH v4] box: fixed comparison of old and new config options

[tarantool-patches] [PATCH v4] box: fixed comparison of old and new config options

[Olga Arkhangelskaia]

box.cfg() updates only those options that have actually changed.
However, for replication it is not always true: box.cfg{replication = x}
and box.cfg{replication = {x}} are treated differently, and as
the result - replication is restarted. The patch fixes such behaviour.

Closes #3711
---
Issue:
https://github.com/tarantool/tarantool/issues/3711
Branch:
https://github.com/tarantool/tarantool/tree/OKriw/gh-3711-do-not-restart-replication-if-config-did-not-change-1.10

v1:
https://www.freelists.org/post/tarantool-patches/PATCH-box-fixed-comparison-of-old-and-new-config-options

v2:
https://www.freelists.org/post/tarantool-patches/PATCH-v2-box-fixed-comparison-of-old-and-new-config-options

v3:
https://www.freelists.org/post/tarantool-patches/PATCH-v3-box-fixed-comparison-of-old-and-new-config-options
Changes in v2:
- changed test
- conversion from num to string now in modify_cfg
- no sort table in comparison
- got rid of table.getn

Changes in v3:
- changed test
- fixed comments, names, identation
- added normalize_uri_list

Changes in v3:
- fixed test
- now we transform value 1234 into {'1234'} for replication
- fixed indentaion
  

 src/box/lua/load_cfg.lua         |  40 +++++++++++++--
 test/replication/errinj.result   |   2 +-
 test/replication/errinj.test.lua |   2 +-
 test/replication/misc.result     | 102 ++++++++++++++++++++++++++++++++++++++-
 test/replication/misc.test.lua   |  41 +++++++++++++++-
 5 files changed, 180 insertions(+), 7 deletions(-)

diff --git a/src/box/lua/load_cfg.lua b/src/box/lua/load_cfg.lua
index f62f4dc1e..33221362c 100644
--- a/src/box/lua/load_cfg.lua
+++ b/src/box/lua/load_cfg.lua
@@ -151,10 +151,22 @@ local function normalize_uri(port)
     return tostring(port);
 end
 
+local function normalize_uri_list(port_list)
+    local ports_table = {}
+    if type(port_list) == 'table' then
+        for i in pairs(port_list) do
+            table.insert(ports_table, normalize_uri(port_list[i]))
+        end
+    else
+        table.insert(ports_table, normalize_uri(port_list))
+    end
+    return ports_table;
+end
+
 -- options that require special handling
 local modify_cfg = {
     listen             = normalize_uri,
-    replication        = normalize_uri,
+    replication        = normalize_uri_list,
 }
 
 local function purge_password_from_uri(uri)
@@ -365,6 +377,28 @@ local function apply_default_cfg(cfg, default_cfg)
     end
 end
 
+-- Return true if two configurations are equivalent.
+local function compare_cfg(t1, t2)
+    if type(t1) ~= 'table' and type(t2) ~= 'table' then
+        return t1 == t2
+    end
+    if (type(t1) == 'table' and type(t2) ~= 'table') or
+       (type(t2) == 'table' and type(t1) ~= 'table') then
+        return false
+    end
+    if type(t1) == 'table' and type(t2) == 'table' then
+        if #t1 ~= #t2 then
+            return false
+        end
+        for i, j in pairs(t2) do
+            if t1[i] ~= j then
+                return false
+            end
+        end
+        return true
+    end
+end
+
 local function reload_cfg(oldcfg, cfg)
     cfg = upgrade_cfg(cfg, translate_cfg)
     local newcfg = prepare_cfg(cfg, default_cfg, template_cfg, modify_cfg)
@@ -377,7 +411,7 @@ local function reload_cfg(oldcfg, cfg)
     for key in pairs(cfg) do
         local val = newcfg[key]
         local oldval = oldcfg[key]
-        if oldval ~= val then
+        if not compare_cfg(val, oldval) then
             rawset(oldcfg, key, val)
             if not pcall(dynamic_cfg[key]) then
                 rawset(oldcfg, key, oldval) -- revert the old value
@@ -452,7 +486,7 @@ local function load_cfg(cfg)
         local val = cfg[key]
         if val ~= nil and not dynamic_cfg_skip_at_load[key] then
             fun()
-            if val ~= default_cfg[key] then
+            if not compare_cfg(val, default_cfg[key]) then
                 log.info("set '%s' configuration option to %s", key, json.encode(val))
             end
         end
diff --git a/test/replication/errinj.result b/test/replication/errinj.result
index ce6add8d4..2e7d367c7 100644
--- a/test/replication/errinj.result
+++ b/test/replication/errinj.result
@@ -383,7 +383,7 @@ while box.info.replication[1].upstream ~= nil do fiber.sleep(0.0001) end
 ---
 ...
 -- reconnect
-box.cfg{replication = {old_repl}}
+box.cfg{replication = old_repl}
 ---
 ...
 while box.info.replication[1].upstream.status ~= 'disconnected' do fiber.sleep(0.0001) end
diff --git a/test/replication/errinj.test.lua b/test/replication/errinj.test.lua
index e1e96a0c4..32e0be912 100644
--- a/test/replication/errinj.test.lua
+++ b/test/replication/errinj.test.lua
@@ -160,7 +160,7 @@ old_repl = box.cfg.replication
 box.cfg{replication = {}, replication_timeout = 0.1}
 while box.info.replication[1].upstream ~= nil do fiber.sleep(0.0001) end
 -- reconnect
-box.cfg{replication = {old_repl}}
+box.cfg{replication = old_repl}
 while box.info.replication[1].upstream.status ~= 'disconnected' do fiber.sleep(0.0001) end
 while box.info.replication[1].upstream.status ~= 'follow' do fiber.sleep(0.0001) end
 
diff --git a/test/replication/misc.result b/test/replication/misc.result
index f8aa8dab6..ec0a94c1d 100644
--- a/test/replication/misc.result
+++ b/test/replication/misc.result
@@ -413,7 +413,7 @@ test_run:cmd("switch replica")
 ---
 - true
 ...
-replication = box.cfg.replication
+replication = box.cfg.replication[1]
 ---
 ...
 box.cfg{replication = {replication, replication}}
@@ -467,3 +467,103 @@ test_run:cmd("delete server replica")
 box.schema.user.revoke('guest', 'replication')
 ---
 ...
+--
+-- gh-3711 Do not restart replication on box.cfg if the configuration didn't change
+--
+box.schema.user.grant('guest', 'replication')
+---
+...
+test_run:cmd("create server replica with rpl_master=default, script='replication/replica.lua'")
+---
+- true
+...
+test_run:cmd("start server replica")
+---
+- true
+...
+test_run:cmd("switch replica")
+---
+- true
+...
+replication = box.cfg.replication[1]
+---
+...
+test_run:cmd("switch default")
+---
+- true
+...
+-- Access rights are checked only during reconnect. If new config is equivalent
+-- to old one, replication will continue working.
+box.schema.user.revoke('guest', 'replication')
+---
+...
+test_run:cmd("switch replica")
+---
+- true
+...
+box.cfg{replication = {replication}}
+---
+...
+box.info.status == 'running'
+---
+- true
+...
+box.cfg{replication = replication}
+---
+...
+box.info.status == 'running'
+---
+- true
+...
+-- check table
+test_run:cmd("switch default")
+---
+- true
+...
+box.schema.user.grant('guest', 'replication')
+---
+...
+test_run:cmd("switch replica")
+---
+- true
+...
+replication = box.cfg.replication
+---
+...
+table.insert(replication, box.cfg.listen)
+---
+...
+test_run:cmd("switch default")
+---
+- true
+...
+box.schema.user.revoke('guest', 'replication')
+---
+...
+test_run:cmd("switch replica")
+---
+- true
+...
+box.cfg{replication = replication}
+---
+...
+box.info.status == 'running'
+---
+- true
+...
+test_run:cmd("switch default")
+---
+- true
+...
+test_run:cmd("stop server replica")
+---
+- true
+...
+test_run:cmd("cleanup server replica")
+---
+- true
+...
+test_run:cmd("delete server replica")
+---
+- true
+...
diff --git a/test/replication/misc.test.lua b/test/replication/misc.test.lua
index 46726b7f4..cbdfc7cdd 100644
--- a/test/replication/misc.test.lua
+++ b/test/replication/misc.test.lua
@@ -171,7 +171,7 @@ box.schema.user.grant('guest', 'replication')
 test_run:cmd("create server replica with rpl_master=default, script='replication/replica.lua'")
 test_run:cmd("start server replica")
 test_run:cmd("switch replica")
-replication = box.cfg.replication
+replication = box.cfg.replication[1]
 box.cfg{replication = {replication, replication}}
 
 -- Check the case when duplicate connection is detected in the background.
@@ -191,3 +191,42 @@ test_run:cmd("stop server replica")
 test_run:cmd("cleanup server replica")
 test_run:cmd("delete server replica")
 box.schema.user.revoke('guest', 'replication')
+
+
+--
+-- gh-3711 Do not restart replication on box.cfg if the configuration didn't change
+--
+box.schema.user.grant('guest', 'replication')
+
+test_run:cmd("create server replica with rpl_master=default, script='replication/replica.lua'")
+test_run:cmd("start server replica")
+test_run:cmd("switch replica")
+replication = box.cfg.replication[1]
+test_run:cmd("switch default")
+-- Access rights are checked only during reconnect. If new config is equivalent
+-- to old one, replication will continue working.
+box.schema.user.revoke('guest', 'replication')
+test_run:cmd("switch replica")
+box.cfg{replication = {replication}}
+box.info.status == 'running'
+box.cfg{replication = replication}
+box.info.status == 'running'
+
+-- check table
+test_run:cmd("switch default")
+box.schema.user.grant('guest', 'replication')
+test_run:cmd("switch replica")
+replication = box.cfg.replication
+table.insert(replication, box.cfg.listen)
+
+test_run:cmd("switch default")
+box.schema.user.revoke('guest', 'replication')
+
+test_run:cmd("switch replica")
+box.cfg{replication = replication}
+box.info.status == 'running'
+
+test_run:cmd("switch default")
+test_run:cmd("stop server replica")
+test_run:cmd("cleanup server replica")
+test_run:cmd("delete server replica")
-- 
2.14.3 (Apple Git-98)

Re: [tarantool-patches] [PATCH v4] box: fixed comparison of old and new config options

[Vladimir Davydov]

Pushed to 1.10-features.