[tarantool-patches] Re: [PATCH][vshard] Log warning on duplicate replica.name

[Alex Khatskevich <avkhatskevich@tarantool.org>]

> Please, print the warning on each duplicate only once. Now if I use 
> the same name
> N >= 2 times, the warning for the name is printed N - 1 times.
>
> Example:
>
>     name1, name1, name1, name1
>
> In the log I see:
>
>     Duplicate replica.name found: name1
>     Duplicate replica.name found: name1
>     Duplicate replica.name found: name1
>
> Must be:
>
>     Duplicate replica.name found: name1
>
> For example, you can store in 'names' not booleans, but count of name
> duplicates. And print the warning only when the count is 2.
Fixed

New diff:

commit c1d573d035994723c11b2c0e7151f52f67dd5d55
Author: AKhatskevich <avkhatskevich@tarantool.org>
Date:   Thu Jun 7 14:43:16 2018 +0300

     Log warning on duplicate replica.name

     In case duplicate replica.name found, log warning.
     Message appears once for each unique duplicate.

     Closes #101

diff --git a/test/unit/config.result b/test/unit/config.result
index 8449ec3..b82303b 100644
--- a/test/unit/config.result
+++ b/test/unit/config.result
@@ -120,13 +120,13 @@ cfg.sharding['rsid2'] = nil
  ---
  ...
  -- UUID duplicate in different replicasets.
-replicaset2 = {replicas = {['id3'] = {uri = 'uri:uri@uri2', name = 
'storage', master = true}}}
+replicaset2 = {replicas = {['id3'] = {uri = 'uri:uri@uri2', name = 
'storage2', master = true}}}
  ---
  ...
  cfg.sharding['rsid2'] = replicaset2
  ---
  ...
-replicaset3 = {replicas = {['id3'] = {uri = 'uri:uri@uri3', name = 
'storage', master = true}}}
+replicaset3 = {replicas = {['id3'] = {uri = 'uri:uri@uri3', name = 
'storage3', master = false}}}
  ---
  ...
  cfg.sharding['rsid3'] = replicaset3
@@ -136,6 +136,64 @@ check(cfg)
  ---
  - Duplicate uuid id3
  ...
+cfg.sharding['rsid3'] = nil
+---
+...
+cfg.sharding['rsid2'] = nil
+---
+...
+--
+-- gh-101: Log warning in case replica.name duplicate found.
+--
+-- name duplicate in one replicaset.
+replica2_1 = {uri = 'uri:uri@uri2_1', name = 'dup_name1', master = true}
+---
+...
+replica2_2 = {uri = 'uri:uri@uri2_2', name = 'dup_name1', master = false}
+---
+...
+replicaset2 = {replicas = {['id2'] = replica2_1, ['id3'] = replica2_2}}
+---
+...
+cfg.sharding['rsid2'] = replicaset2
+---
+...
+_ = check(cfg)
+---
+...
+test_run:grep_log('default', 'Duplicate replica.name found: dup_name1')
+---
+- 'Duplicate replica.name found: dup_name1'
+...
+cfg.sharding['rsid2'] = nil
+---
+...
+-- name duplicate in different replicasets.
+replica2 = {uri = 'uri:uri@uri2', name = 'dup_name2', master = true}
+---
+...
+replica3 = {uri = 'uri:uri@uri3', name = 'dup_name2', master = true}
+---
+...
+replicaset2 = {replicas = {['id2'] = replica2}}
+---
+...
+replicaset3 = {replicas = {['id3'] = replica3}}
+---
+...
+cfg.sharding['rsid2'] = replicaset2
+---
+...
+cfg.sharding['rsid3'] = replicaset3
+---
+...
+_ = check(cfg)
+---
+...
+test_run:grep_log('default', 'Duplicate replica.name found: dup_name2')
+---
+- 'Duplicate replica.name found: dup_name2'
+...
  cfg.sharding['rsid2'] = nil
  ---
  ...
diff --git a/test/unit/config.test.lua b/test/unit/config.test.lua
index 0b01b3e..9b2b7be 100644
--- a/test/unit/config.test.lua
+++ b/test/unit/config.test.lua
@@ -57,11 +57,36 @@ check(cfg)
  cfg.sharding['rsid2'] = nil

  -- UUID duplicate in different replicasets.
-replicaset2 = {replicas = {['id3'] = {uri = 'uri:uri@uri2', name = 
'storage', master = true}}}
+replicaset2 = {replicas = {['id3'] = {uri = 'uri:uri@uri2', name = 
'storage2', master = true}}}
  cfg.sharding['rsid2'] = replicaset2
-replicaset3 = {replicas = {['id3'] = {uri = 'uri:uri@uri3', name = 
'storage', master = true}}}
+replicaset3 = {replicas = {['id3'] = {uri = 'uri:uri@uri3', name = 
'storage3', master = false}}}
  cfg.sharding['rsid3'] = replicaset3
  check(cfg)
+cfg.sharding['rsid3'] = nil
+cfg.sharding['rsid2'] = nil
+
+--
+-- gh-101: Log warning in case replica.name duplicate found.
+--
+
+-- name duplicate in one replicaset.
+replica2_1 = {uri = 'uri:uri@uri2_1', name = 'dup_name1', master = true}
+replica2_2 = {uri = 'uri:uri@uri2_2', name = 'dup_name1', master = false}
+replicaset2 = {replicas = {['id2'] = replica2_1, ['id3'] = replica2_2}}
+cfg.sharding['rsid2'] = replicaset2
+_ = check(cfg)
+test_run:grep_log('default', 'Duplicate replica.name found: dup_name1')
+cfg.sharding['rsid2'] = nil
+
+-- name duplicate in different replicasets.
+replica2 = {uri = 'uri:uri@uri2', name = 'dup_name2', master = true}
+replica3 = {uri = 'uri:uri@uri3', name = 'dup_name2', master = true}
+replicaset2 = {replicas = {['id2'] = replica2}}
+replicaset3 = {replicas = {['id3'] = replica3}}
+cfg.sharding['rsid2'] = replicaset2
+cfg.sharding['rsid3'] = replicaset3
+_ = check(cfg)
+test_run:grep_log('default', 'Duplicate replica.name found: dup_name2')
  cfg.sharding['rsid2'] = nil
  cfg.sharding['rsid3'] = nil

diff --git a/vshard/cfg.lua b/vshard/cfg.lua
index a389eea..7a25cc9 100644
--- a/vshard/cfg.lua
+++ b/vshard/cfg.lua
@@ -141,6 +141,7 @@ end
  local function check_sharding(sharding)
      local uuids = {}
      local uris = {}
+    local names = {}
      for replicaset_uuid, replicaset in pairs(sharding) do
          if uuids[replicaset_uuid] then
              error(string.format('Duplicate uuid %s', replicaset_uuid))
@@ -159,6 +160,18 @@ local function check_sharding(sharding)
                  error(string.format('Duplicate uuid %s', replica_uuid))
              end
              uuids[replica_uuid] = true
+            -- Log warning in case replica.name duplicate found.
+            -- Message appears once for each unique duplicate.
+            local name = replica.name
+            if name then
+                if names[name] == nil then
+                    names[name] = 1
+                elseif names[name] == 1 then
+                    log.warn('Duplicate replica.name found: %s', name)
+                    -- Next duplicates should not be reported.
+                    names[name] = 2
+                end
+            end
          end
      end
  end