Not able to ready the post body when using with ngx.eof

suchit.puri

Hi Guys,

We are migrating our production servers from openresty/1.7.4.1 to openresty/1.9.7.3 , earlier when using version 1.7.4.1 we used to call ngx.eof() as the first line so as to send an empty output to the user. Now with 1.9.7.3 when we try to do the same we are not able to ready the post data body using ngx.req.read_body() followed by ngx.req.get_body_data() . is this expected behaviour ? cause Ideally the input buffers should not be affected by the output ones.

Regards

Suchit Puri

agentzh

Hello!

On Wed, Apr 6, 2016 at 1:49 AM, Suchit Puri wrote:
> We are migrating our production servers from openresty/1.7.4.1 to
> openresty/1.9.7.3 , earlier when using version 1.7.4.1  we used to call
> ngx.eof() as the first line so as to send an empty output to the user. Now
> with 1.9.7.3  when we try to do the same we are not able to ready the post
> data body using ngx.req.read_body() followed by ngx.req.get_body_data() . is
> this expected behaviour ? cause Ideally the input buffers should not be
> affected by the output ones.

Will you provide a minimal and standalone example that we can run
easily on our side?

Regarding your usage itself, it's recommended to read the request body
before calling ngx.eof() since some HTTP clients may prematurely close
the connection when they see the whole response body from the server.

Regards,
-agentzh

suchit.puri

Hi Yichun,

Apologies for late reply, here is the sample example.

location = /test {
     content_by_lua '
         ngx.req.read_body()
         local args, err = ngx.req.get_post_args()
         if not args then
             ngx.say("failed to get post args: ", err)
             return
         end
         for key, val in pairs(args) do
             if type(val) == "table" then
                 ngx.say(key, ": ", table.concat(val, ", "))
             else
                 ngx.say(key, ": ", val)
             end
         end
     ';
 }

location = /test2 {
     content_by_lua '

        pcall(ngx.eof)

         ngx.req.read_body()

         local args, err = ngx.req.get_post_args()
         if not args then
             ngx.say("failed to get post args: ", err)
             return
         end
         for key, val in pairs(args) do
             if type(val) == "table" then
                 ngx.say(key, ": ", table.concat(val, ", "))
             else
                 ngx.say(key, ": ", val)
             end
         end
     ';
 }

in the second example, since we call pcall(ngx.eof) in the first line we get the arguments as null.

Thanks

Suchit Puri

On Wed, Apr 6, 2016 at 9:47 PM, Yichun Zhang (agentzh) <age...@gmail.com> wrote:

Hello!

On Wed, Apr 6, 2016 at 1:49 AM, Suchit Puri wrote:
> We are migrating our production servers from openresty/1.7.4.1 to
> openresty/1.9.7.3 , earlier when using version 1.7.4.1 we used to call
> ngx.eof() as the first line so as to send an empty output to the user. Now
> with 1.9.7.3 when we try to do the same we are not able to ready the post
> data body using ngx.req.read_body() followed by ngx.req.get_body_data() . is
> this expected behaviour ? cause Ideally the input buffers should not be
> affected by the output ones.

Will you provide a minimal and standalone example that we can run
easily on our side?

Regarding your usage itself, it's recommended to read the request body
before calling ngx.eof() since some HTTP clients may prematurely close
the connection when they see the whole response body from the server.

Regards,
-agentzh

.

Suchit Puri

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agentzh

Hello!

On Mon, Apr 11, 2016 at 4:46 AM, Suchit Puri wrote:
> location = /test2 {
>      content_by_lua '
>
>         pcall(ngx.eof)
>
>          ngx.req.read_body()
>

Just to repeat my previous reply:

"read the request body
before calling ngx.eof() since some HTTP clients may prematurely close
the connection when they see the whole response body from the server."

Regards,
-agentzh