[Tarantool-patches] [PATCH] box: provide a user friendly frontend for accessing session settings

[Vladislav Shpilevoy]

Hi!

Is this patch in scope of the other patches of the same thread?
If it is, it should be sent together with them. Otherwise I don't
see what is going to be pushed if I will give ok to the patch.

I see that at least sql patch is changed, but it not resent.

See 3 comments below.

On 17/03/2020 18:21, Chris Sosnin wrote:
> - space_object:update() is hard to use for configuring session settings,
> so we provide box.session.setting table, which can be used in a much more
> native way.
> 
> - Prior to this patch sql settings were not accessible before box.cfg()
> call, even though these flags can be set right after session creation.
> 
> Part of #4711
> ---
> This patch provides the following syntax as was suggested by Nikita:
> box.session.settings.<name> = <value>. Doc request in sql-patch is

1. In the commit message you said 'box.session.setting'. Not 'settings'.
What option did you want to use?

> updated too.
> 
> Note, that I had to break the null - error message rule as long as
> __newindex doesn't return anything, the only way to tell the user
> about the error is to raise it.
> 
> I moved it to the new branch:
> branch:https://github.com/tarantool/tarantool/tree/ksosnin/gh-4712-session-settings-v2
> issuse:https://github.com/tarantool/tarantool/issues/4711
> 
> diff --git a/src/box/lua/session.c b/src/box/lua/session.c
> index c6a600f6f..66d59c8c7 100644
> --- a/src/box/lua/session.c
> +++ b/src/box/lua/session.c
> @@ -411,6 +413,116 @@ lbox_session_on_access_denied(struct lua_State *L)
>  				  lbox_push_on_access_denied_event, NULL);
>  }
>  
> +static int
> +lbox_session_setting_get_by_id(struct lua_State *L)

2. This function is never called from Lua. You don't need
to pass ID via Lua stack. Add it as a C argument.

> +{
> +	assert(lua_type(L, -1) == LUA_TNUMBER);
> +	int sid = lua_tointeger(L, -1);
> +	lua_pop(L, 1);
> +	const char *mp_pair, *mp_pair_end;
> +	session_settings[sid].get(sid, &mp_pair, &mp_pair_end);
> +	uint32_t len;
> +	mp_decode_array(&mp_pair);
> +	mp_decode_str(&mp_pair, &len);
> +	enum field_type field_type = session_settings[sid].field_type;
> +	if (field_type == FIELD_TYPE_BOOLEAN) {
> +		bool value = mp_decode_bool(&mp_pair);
> +		lua_pushboolean(L, value);
> +	} else {
> +		assert(field_type == FIELD_TYPE_STRING);
> +		const char *str = mp_decode_str(&mp_pair, &len);
> +		lua_pushlstring(L, str, len);
> +	}
> +	return 1;
> +}
> +
> +static int
> +lbox_session_setting_get(struct lua_State *L) {

3. Please, use a separate line for {. The same for serialize.