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

[Vladislav Shpilevoy <v.shpilevoy@tarantool.org>]

Thanks the patch! Almost perfect. But one minor comment. See it below.

On 07/06/2018 14:50, AKhatskevich wrote:
> In case duplicate replica.name found, log warning.
> 
> Closes #101
> ---
> Branch: https://github.com/tarantool/vshard/tree/kh/gh-101-duplicate_name_warning
> Issue: https://github.com/tarantool/vshard/issues/101
>   test/unit/config.result   | 62 +++++++++++++++++++++++++++++++++++++++++++++--
>   test/unit/config.test.lua | 29 ++++++++++++++++++++--
>   vshard/cfg.lua            |  8 ++++++
>   3 files changed, 95 insertions(+), 4 deletions(-)
> 
> diff --git a/vshard/cfg.lua b/vshard/cfg.lua
> index a389eea..c3cf5d7 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 +160,13 @@ 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
> +            if replica.name then
> +                if names[replica.name] then
> +                    log.warn('Duplicate replica.name found: %s', replica.name)
> +                end
> +                names[replica.name] = true

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.

> +            end
>           end
>       end
>   end
>