[tarantool-patches] Re: [PATCH v1 1/1] box: fix custom delimiter for telnet connection

[Alexander Turenko <alexander.turenko@tarantool.org>]

This patch looks good for me, except several minor things.

Can we write a test for the new behaviour?

WBR, Alexander Turenko.

On Thu, Feb 21, 2019 at 10:34:55AM +0300, Kirill Shcherbatov wrote:
> Because test-run uses a console connection to run tests, the
> actual string delimiter was the user-specified delimiter
> delim + "\n".

'test-run uses a console connection' says nothing about why a newline is
added to a delimiter. I would say:

In order to give a user ability to use a delimiter symbol within a
code the real delimiter is user-provided 'delim' plus '\n'.

> Since telnet sends \r\n on line break, the updated expression
> delim + "\n"could not be found in a sequence data+delim+"\r\n",

Forgotten whitespace after the first "\n".

> so delimiter feature did not work at all.
> Added delim + "\r" check along with delim + "\n", that solves the
> described problem and does not violate backward compatibility.
> 
> Closes #2027
> 
> https://github.com/tarantool/tarantool/tree/kshch/gh-2027-telnet-alternative-delimiter
> https://github.com/tarantool/tarantool/issues/2027
> ---
>  src/box/lua/console.lua | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/src/box/lua/console.lua b/src/box/lua/console.lua
> index 028001127..bdedcb393 100644
> --- a/src/box/lua/console.lua
> +++ b/src/box/lua/console.lua
> @@ -344,8 +344,9 @@ end
>  -- Read command from connected client console.listen()
>  --
>  local function client_read(self)
> -    local delim = self.delimiter .. "\n"
> -    local buf = self.client:read(delim)
> +    local delim_lf = self.delimiter .. "\n"
> +    local delim_cr = self.delimiter .. "\r"

I would comment here why we need delim_cr (in short).

> +    local buf = self.client:read({delimiter = {delim_lf, delim_cr}})
>      if buf == nil then
>          return nil
>      elseif buf == "" then
> @@ -355,7 +356,7 @@ local function client_read(self)
>          return nil
>      end
>      -- remove trailing delimiter
> -    return buf:sub(1, -#delim-1)
> +    return buf:sub(1, -#delim_lf-1)

I would use `-#self.delimiter` to make the code simmetric btw delim_cr /
delim_lf.

>  end
>  
>  --
> -- 
> 2.20.1
>