Stop supporting R15B03 and older

[michalwski]

I think we can stop supporting older Erlang/OTP versions than R16. Here are some reasons (and action points) regarding this:

1. We can merge with paulgray/exml and benefit from he's NIF's reductions introduced in paulgray/exml@3e9d223
2. We can remove custom cowboy dep [1].
3. We can start using application:get_env/3 instead of application:get_env/2 and additional lines of code holding default value.
4. One job less on travis.

Probably some other improvements can be done but I let (and encourage) the team @esl/mongooseim-developers to comment on this issue and share other ideas :)

[1].

MongooseIM/rebar.config.script

Lines 3 to 8 in 23cb2de

	"R15" ++ _ ->
	{deps, Deps} = lists:keyfind(deps, 1, CONFIG),
	io:format("using patched cowboy 1.0.1 for Erlang/OTP R15B03~n"),
	CowDep = {cowboy,".*", {git,"git://github.com/michalwski/cowboy.git",{branch,"1.0.1-R15"}}},
	NewDeps = lists:keyreplace(cowboy, 1, Deps, CowDep),
	lists:keyreplace(deps, 1, CONFIG, {deps, NewDeps});

[fenek]

👍

We could remove walkaround for binary_to_integer and integer_to_binary as well!

[pzel]

Yes, this would allow us to clean up quite a bit of accumulated kludges!

On Thu, Nov 12, 2015 at 11:34 AM, Piotr Nosek notifications@github.com
wrote:

[image: 👍]

We could remove walkaround for binary_to_integer and integer_to_binary as
well!

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Reply to this email directly or view it on GitHub
#582 (comment).

Simon Zelazny
Erlang Solutions, Ltd.

[michalwski]

TODO list after ditching support for R15

• merge Merge with paulgray/exml exml#16
• remve custom cowboy version see reabar.config.script
• use application:get_env/3 when default value is needed
• use application:ensure_all_started instead of custom mechanism
• remove workaround for binary_to_integer in rebar.config and look for all places where no_binary_to_integer is used. Remember to remove ejabberd_binary:binary_to_integer and ejabberd_binary:integer_to_binary
• remove workaround for crypto:hmac in rebar.config and look for all places where no_crypto_hmac is used

[michalwski]

Closed by #613.
To benefit this change we should also merge esl/exml#16