Upgrade the erlang-server dependency from cowboy1.x to cowboy2.x

[feihongmeilian]

Use erlang-server with erlang.mk

1, Create an application by using erlang.mk
$ mkdir http_server
$ cd http_server
$ wget https://erlang.mk/erlang.mk
$ make -f erlang.mk bootstrap bootstrap-rel
$ make run

2, Modify the Makefile in the http_server directory to the following to introduce the dependency library：
PROJECT = http_server
PROJECT_DESCRIPTION = New project
PROJECT_VERSION = 0.1.0

DEPS = cowboy jesse jsx
dep_cowboy_commit = 2.5.0
dep_jesse_commit = 1.5.2
dep_jsx_commit = 2.9.0
DEP_PLUGINS = cowboy jesse jsx

PACKAGES += rfc3339
pkg_rfc3339_name = rfc3339
pkg_rfc3339_description = an erlang/elixir rfc3339 lib
pkg_rfc3339_homepage = https://github.com/talentdeficit/rfc3339
pkg_rfc3339_fetch = git
pkg_rfc3339_repo = https://github.com/talentdeficit/rfc3339
pkg_rfc3339_commit = master

 include erlang.mk

3，Generate erlang-server project using openapi-generator
https://github.com/OpenAPITools/openapi-generator#2---getting-started

4， Copy erlang-server file to http_server project

5，Start in the http_server project：
1，Introduce the following line in the start(_Type, _Args) function
openapi_server:start(http_server, #{ip=>{127,0,0,1}, port=>8080, net_opts=>[]}),
2，Compilation http_server project
$ make
3，Start erlang virtual machine
$erl -pa ./deps/cowboy/ebin -pa ./deps/cowlib/ebin -pa ./deps/ranch/ebin -pa ./deps/jsx/ebin -pa ./deps/jesse/ebin -pa ./deps/rfc3339/ebin -pa ./ebin
4, Start project
application:ensure_all_started(http_server).

[wing328]

@feihongmeilian thanks for the PR.

cc @tsloughter (2017/11) @jfacorro (2018/10) @robertoaloi (2018/10) (technical committee),
@galaxie (author of the Erlang server generator)

[wing328]

Can you please uncomment the following line to see if the CI tests pass?

openapi-generator/pom.xml

Line 1226 in 8f61ace

<module>samples/server/petstore/erlang-server</module> -->

[wing328]

The Erlang petstore server builds without issue.

If no further feedback from anyone, I'll merge it into 4.0.x on coming Wed.

(4.0.0 will be released on Dec 20th)

[wing328]

@feihongmeilian thanks for the contribution, which has been included in the 4.0.0-beta release: https://twitter.com/oas_generator/status/1079727020374806529.

Happy New Year and looking forward to more collaboration and contributions in 2019!