[Tarantool-patches] [PATCH v2] replication: add box.info.replication_anon

[Vladislav Shpilevoy]

Hi! Thanks for the patch!

>     Closes #4900
>     
>     @TarantoolBot document
>     Title: add new field to box.info: replication_anon
>     
>     It is now possible to list all the anonymous replicas following the
>     instance with a call to `box.info.replication_anon()`
>     The output is similar to the one produced by `box.info.replication` with
>     an exception that anonymous replicas are indexed by their uuid strings
>     rather then server ids, since server ids have no meaning for anonymous
>     replicas.
>     
>     Note, that when you issue a plain `box.info.replication_anon`, the only
>     info returned is the number of anonymous replicas following the current
>     instance. In order to see the full stats, you have to call
>     `box.info.replication_anon()` . This is done to not overload the `box.info`
>     output with excess  info, since there may be lots of anonymous replicas.

Double whitespaces on this line and previous.

Also see 2 nits about comments below.

> diff --git a/src/box/lua/info.c b/src/box/lua/info.c
> index a789f7822..e7318fcd1 100644
> --- a/src/box/lua/info.c
> +++ b/src/box/lua/info.c
> @@ -214,6 +214,54 @@ lbox_info_replication(struct lua_State *L)
>  	return 1;
>  }
>  
> +static int
> +lbox_info_replication_anon_call(struct lua_State *L)
> +{
> +	lua_newtable(L); /* box.info.replication_anon */
> +
> +	/* Nice formatting */
> +	lua_newtable(L); /* metatable */

1. Better write comments on separate lines, use '.' in the end
of sentences and capital letters when start them.

> +	lua_pushliteral(L, "mapping");
> +	lua_setfield(L, -2, "__serialize");
> +	lua_setmetatable(L, -2);
> +
> +	replicaset_foreach(replica) {
> +		if (!replica->anon)
> +			continue;
> +
> +		lua_pushstring(L, tt_uuid_str(&replica->uuid));
> +		lbox_pushreplica(L, replica);
> +
> +		lua_settable(L, -3);
> +	}
> +
> +	return 1;
> +}
> +
> +static int
> +lbox_info_replication_anon(struct lua_State *L)
> +{
> +	/*
> +	 * Make the .replication_anon field callable in order to
> +	 * not flood the output with possibly lots of anonymous
> +	 * replicas on box.info call.
> +	 */
> +	lua_newtable(L);
> +
> +	lua_pushliteral(L, "count");
> +	lua_pushinteger(L, replicaset.anon_count);
> +	lua_settable(L, -3);
> +
> +	lua_newtable(L); /* metatable */

2. Here too.

> +
> +	lua_pushstring(L, "__call");
> +	lua_pushcfunction(L, lbox_info_replication_anon_call);
> +	lua_settable(L, -3);
> +
> +	lua_setmetatable(L, -2);
> +	return 1;
> +}