Is there a way to get http code instead of error message from tcpsock:send(data)?

toku463ne · 2017-03-15T10:28:00+00:00

Hi, you cannot have too light thread write one socket.Here is official document.Starting from the 0.9.9 release, the cosocket object here is full-d...

Is there a way to get http code instead of error message from tcpsock:send(data)?

toku463ne

I created a lua script to reverse proxy requests.

I want to set http code from upstreams to ngx.status.

Currently we do like below.

===

local sock, err = ngx_socket_tcp()

local bytes, err = sock:send(req)

if err == "timeout" then

ngx.status = ngx.HTTP_GATEWAY_TIMEOUT

end

With this we can return 504 error in case we get "timeout" from upstream.

But what I want to do is to reply the http status code from upstream to the client.

Concretely I created script below.

===

function error_proc( loglevel, msg )
  ngx.log(loglevel, msg)
  if msg == "timeout" then
    ngx.status = ngx.HTTP_GATEWAY_TIMEOUT
  end
end


local host = ngx.var.target_host
local port = ngx.var.target_port
local timeout = ngx.var.target_timeout
if not port then
  port = 80
end
local ssl = ngx.var.target_ssl
if not ssl then
  ssl = no
end

local http = require "resty.http"
local httpc = http.new()


httpc:set_timeout(timeout)
ngx.log(ngx.DEBUG, "Connecting to " .. host .. ngx.var.request_uri)
local ok, err = httpc:connect(host, port) 
if not ok then
  error_proc(ngx.ERR, err)
  return
end

if ssl == "on" then
  ngx.log(ngx.DEBUG, "Conducting ssl handshake")
  local session, err = httpc:ssl_handshake{server_name=host}
  if err then
    error_proc(ngx.ERR, err)
    return
  end
end


ngx.log(ngx.DEBUG, "Sending request to "..host)
local res, err = httpc:proxy_request()
if err then
  error_proc(ngx.ERR, err)
  return
end
ngx.log(ngx.DEBUG, "Transferring request from "..host.." to "..ngx.var.remote_addr)
httpc:proxy_response(res)
httpc:set_keepalive()

rpaprocki

Hi,

On Tue, Mar 14, 2017 at 7:28 PM, Mine Kot <toku...@gmail.com> wrote:

I created a lua script to reverse proxy requests.
I want to set http code from upstreams to ngx.status.

Currently we do like below.
===
local sock, err = ngx_socket_tcp()
local bytes, err = sock:send(req)
if err == "timeout" then
ngx.status = ngx.HTTP_GATEWAY_TIMEOUT
end

With this we can return 504 error in case we get "timeout" from upstream.
But what I want to do is to reply the http status code from upstream to the client.

Are you asking if you can get an HTTP status code when there is a socket error? This doesn't really seem possible- if you couldn't successfully contact the upstream via HTTP, how do you expect to have a status code that you can return downstream? You can't expect layer 7 data to be available when lower layers aren't cooperating ;)

If you're asking for something else, have a look at the lua-resty-http implementation to get an idea if someone else has already solved your problem.

On Tue, Mar 14, 2017 at 7:28 PM, Mine Kot <toku...@gmail.com> wrote:

I created a lua script to reverse proxy requests.

I want to set http code from upstreams to ngx.status.

Currently we do like below.

===

local sock, err = ngx_socket_tcp()

local bytes, err = sock:send(req)

if err == "timeout" then

ngx.status = ngx.HTTP_GATEWAY_TIMEOUT

end

With this we can return 504 error in case we get "timeout" from upstream.

But what I want to do is to reply the http status code from upstream to the client.

Concretely I created script below.

===

function error_proc( loglevel, msg )
  ngx.log(loglevel, msg)
  if msg == "timeout" then
    ngx.status = ngx.HTTP_GATEWAY_TIMEOUT
  end
end


local host = ngx.var.target_host
local port = ngx.var.target_port
local timeout = ngx.var.target_timeout
if not port then
  port = 80
end
local ssl = ngx.var.target_ssl
if not ssl then
  ssl = no
end

local http = require "resty.http"
local httpc = http.new()


httpc:set_timeout(timeout)
ngx.log(ngx.DEBUG, "Connecting to " .. host .. ngx.var.request_uri)
local ok, err = httpc:connect(host, port) 
if not ok then
  error_proc(ngx.ERR, err)
  return
end

if ssl == "on" then
  ngx.log(ngx.DEBUG, "Conducting ssl handshake")
  local session, err = httpc:ssl_handshake{server_name=host}
  if err then
    error_proc(ngx.ERR, err)
    return
  end
end


ngx.log(ngx.DEBUG, "Sending request to "..host)
local res, err = httpc:proxy_request()
if err then
  error_proc(ngx.ERR, err)
  return
end
ngx.log(ngx.DEBUG, "Transferring request from "..host.." to "..ngx.var.remote_addr)
httpc:proxy_response(res)
httpc:set_keepalive()

toku463ne

Thank you for your kind reply, and sorry for my late reply.

Actually I am using "resty.http" and as far as I took a look at source code of "resty.http", I believe that proxy_request() method just returns the result of sock:send() function.

So I wondered how we know http codes from the upstream.

2017-03-15 12:42 GMT+09:00 Robert Paprocki <rpap...@fearnothingproductions.net>:

Hi,

On Tue, Mar 14, 2017 at 7:28 PM, Mine Kot <toku...@gmail.com> wrote:
I created a lua script to reverse proxy requests.
I want to set http code from upstreams to ngx.status.

Currently we do like below.
===
local sock, err = ngx_socket_tcp()
local bytes, err = sock:send(req)
if err == "timeout" then
ngx.status = ngx.HTTP_GATEWAY_TIMEOUT
end

With this we can return 504 error in case we get "timeout" from upstream.
But what I want to do is to reply the http status code from upstream to the client.

Are you asking if you can get an HTTP status code when there is a socket error? This doesn't really seem possible- if you couldn't successfully contact the upstream via HTTP, how do you expect to have a status code that you can return downstream? You can't expect layer 7 data to be available when lower layers aren't cooperating ;)

If you're asking for something else, have a look at the lua-resty-http implementation to get an idea if someone else has already solved your problem.
On Tue, Mar 14, 2017 at 7:28 PM, Mine Kot <toku...@gmail.com> wrote:
I created a lua script to reverse proxy requests.
I want to set http code from upstreams to ngx.status.

Currently we do like below.
===
local sock, err = ngx_socket_tcp()
local bytes, err = sock:send(req)
if err == "timeout" then
ngx.status = ngx.HTTP_GATEWAY_TIMEOUT
end

With this we can return 504 error in case we get "timeout" from upstream.
But what I want to do is to reply the http status code from upstream to the client.

Concretely I created script below.
===
function error_proc( loglevel, msg )
  ngx.log(loglevel, msg)
  if msg == "timeout" then
    ngx.status = ngx.HTTP_GATEWAY_TIMEOUT
  end
end


local host = ngx.var.target_host
local port = ngx.var.target_port
local timeout = ngx.var.target_timeout
if not port then
  port = 80
end
local ssl = ngx.var.target_ssl
if not ssl then
  ssl = no
end

local http = require "resty.http"
local httpc = http.new()


httpc:set_timeout(timeout)
ngx.log(ngx.DEBUG, "Connecting to " .. host .. ngx.var.request_uri)
local ok, err = httpc:connect(host, port) 
if not ok then
  error_proc(ngx.ERR, err)
  return
end

if ssl == "on" then
  ngx.log(ngx.DEBUG, "Conducting ssl handshake")
  local session, err = httpc:ssl_handshake{server_name=host}
  if err then
    error_proc(ngx.ERR, err)
    return
  end
end


ngx.log(ngx.DEBUG, "Sending request to "..host)
local res, err = httpc:proxy_request()
if err then
  error_proc(ngx.ERR, err)
  return
end
ngx.log(ngx.DEBUG, "Transferring request from "..host.." to "..ngx.var.remote_addr)
httpc:proxy_response(res)
httpc:set_keepalive()
.

rpaprocki

Does the documentation for lua-resty-http not tell you?

Sent from my iPhone

On Mar 18, 2017, at 06:44, Mine Kot <toku...@gmail.com> wrote:

Hi

Thank you for your kind reply, and sorry for my late reply.

Actually I am using "resty.http" and as far as I took a look at source code of "resty.http", I believe that proxy_request() method just returns the result of sock:send() function.
So I wondered how we know http codes from the upstream.
2017-03-15 12:42 GMT+09:00 Robert Paprocki <rpap...@fearnothingproductions.net>:
Hi,

On Tue, Mar 14, 2017 at 7:28 PM, Mine Kot <toku...@gmail.com> wrote:
I created a lua script to reverse proxy requests.
I want to set http code from upstreams to ngx.status.

Currently we do like below.
===
local sock, err = ngx_socket_tcp()
local bytes, err = sock:send(req)
if err == "timeout" then
ngx.status = ngx.HTTP_GATEWAY_TIMEOUT
end

With this we can return 504 error in case we get "timeout" from upstream.
But what I want to do is to reply the http status code from upstream to the client.

Are you asking if you can get an HTTP status code when there is a socket error? This doesn't really seem possible- if you couldn't successfully contact the upstream via HTTP, how do you expect to have a status code that you can return downstream? You can't expect layer 7 data to be available when lower layers aren't cooperating ;)

If you're asking for something else, have a look at the lua-resty-http implementation to get an idea if someone else has already solved your problem.
On Tue, Mar 14, 2017 at 7:28 PM, Mine Kot <toku...@gmail.com> wrote:
I created a lua script to reverse proxy requests.
I want to set http code from upstreams to ngx.status.

Currently we do like below.
===
local sock, err = ngx_socket_tcp()
local bytes, err = sock:send(req)
if err == "timeout" then
ngx.status = ngx.HTTP_GATEWAY_TIMEOUT
end

With this we can return 504 error in case we get "timeout" from upstream.
But what I want to do is to reply the http status code from upstream to the client.

Concretely I created script below.
===
function error_proc( loglevel, msg )
  ngx.log(loglevel, msg)
  if msg == "timeout" then
    ngx.status = ngx.HTTP_GATEWAY_TIMEOUT
  end
end


local host = ngx.var.target_host
local port = ngx.var.target_port
local timeout = ngx.var.target_timeout
if not port then
  port = 80
end
local ssl = ngx.var.target_ssl
if not ssl then
  ssl = no
end

local http = require "resty.http"
local httpc = http.new()


httpc:set_timeout(timeout)
ngx.log(ngx.DEBUG, "Connecting to " .. host .. ngx.var.request_uri)
local ok, err = httpc:connect(host, port) 
if not ok then
  error_proc(ngx.ERR, err)
  return
end

if ssl == "on" then
  ngx.log(ngx.DEBUG, "Conducting ssl handshake")
  local session, err = httpc:ssl_handshake{server_name=host}
  if err then
    error_proc(ngx.ERR, err)
    return
  end
end


ngx.log(ngx.DEBUG, "Sending request to "..host)
local res, err = httpc:proxy_request()
if err then
  error_proc(ngx.ERR, err)
  return
end
ngx.log(ngx.DEBUG, "Transferring request from "..host.." to "..ngx.var.remote_addr)
httpc:proxy_response(res)
httpc:set_keepalive()
.

toku463ne

Looking more the document, I think l found the answer, as you said.

It should included in the res!

Thank you very much and sorry for annoying you for this.