cowboy/examples/echo_post

= POST parameter echo example

To try this example, you need GNU `make` and `git` in your PATH.

To build and run the example, use the following command:

[source,bash]
$ make run

As this example echoes a POST parameter, it is a little more
complex to test. Some browsers feature tools that allow you
to perform one such request, or you can use the command line
tool `curl` as we will demonstrate.

== HTTP/1.1 example output

[source,bash]
----
$ curl -i -d echo=echomeplz http://localhost:8080
HTTP/1.1 200 OK
connection: keep-alive
server: Cowboy
date: Fri, 28 Sep 2012 04:12:36 GMT
content-length: 9
content-type: text/plain; charset=utf-8

echomeplz
----

== HTTP/2 example output

[source,bash]
----
$ echo echo=echomeplz | nghttp -v -d - http://localhost:8080
[  0.000] Connected
[  0.000] send SETTINGS frame <length=12, flags=0x00, stream_id=0>
          (niv=2)
          [SETTINGS_MAX_CONCURRENT_STREAMS(0x03):100]
          [SETTINGS_INITIAL_WINDOW_SIZE(0x04):65535]
[  0.000] send PRIORITY frame <length=5, flags=0x00, stream_id=3>
          (dep_stream_id=0, weight=201, exclusive=0)
[  0.000] send PRIORITY frame <length=5, flags=0x00, stream_id=5>
          (dep_stream_id=0, weight=101, exclusive=0)
[  0.001] send PRIORITY frame <length=5, flags=0x00, stream_id=7>
          (dep_stream_id=0, weight=1, exclusive=0)
[  0.001] send PRIORITY frame <length=5, flags=0x00, stream_id=9>
          (dep_stream_id=7, weight=1, exclusive=0)
[  0.001] send PRIORITY frame <length=5, flags=0x00, stream_id=11>
          (dep_stream_id=3, weight=1, exclusive=0)
[  0.001] send HEADERS frame <length=43, flags=0x24, stream_id=13>
          ; END_HEADERS | PRIORITY
          (padlen=0, dep_stream_id=11, weight=16, exclusive=0)
          ; Open new stream
          :method: POST
          :path: /
          :scheme: http
          :authority: localhost:8080
          accept: */*
          accept-encoding: gzip, deflate
          user-agent: nghttp2/1.7.1
          content-length: 15
[  0.001] send DATA frame <length=15, flags=0x00, stream_id=13>
[  0.001] send DATA frame <length=0, flags=0x01, stream_id=13>
          ; END_STREAM
[  0.012] recv SETTINGS frame <length=0, flags=0x00, stream_id=0>
          (niv=0)
[  0.012] recv SETTINGS frame <length=0, flags=0x01, stream_id=0>
          ; ACK
          (niv=0)
[  0.012] send SETTINGS frame <length=0, flags=0x01, stream_id=0>
          ; ACK
          (niv=0)
[  0.020] recv (stream_id=13) :status: 200
[  0.020] recv (stream_id=13) content-length: 10
[  0.020] recv (stream_id=13) content-type: text/plain; charset=utf-8
[  0.020] recv (stream_id=13) date: Thu, 09 Jun 2016 09:19:35 GMT
[  0.020] recv (stream_id=13) server: Cowboy
[  0.020] recv HEADERS frame <length=57, flags=0x04, stream_id=13>
          ; END_HEADERS
          (padlen=0)
          ; First response header
echomeplz
[  0.020] recv DATA frame <length=10, flags=0x01, stream_id=13>
          ; END_STREAM
[  0.020] send GOAWAY frame <length=8, flags=0x00, stream_id=0>
          (last_stream_id=0, error_code=NO_ERROR(0x00), opaque_data(0)=[])
----