Added cURL backup method to ApiClient

[aensley]

Attempting to solve the following error in Travis-CI builds with allow_url_fopen disabled:

Unexpected response: 500 fopen(https://codeclimate.com/test_reports): failed to open stream: no suitable wrapper could be found

Example project and build log:
https://github.com/aensley/YahooStockQuotes
https://travis-ci.org/aensley/YahooStockQuotes/jobs/123515259#L314

[jpignata]

@aensley A couple of random (probably dumb – sorry 😄 ) questions:

1. Is it possible for us to toggle this runtime configuration in our test reporter for the duration of the send if it's disabled?
2. If not, would it perhaps be better if we always used libcurl?

[aensley]

@jpignata Those questions aren't dumb at all.

1. I'm not sure in this specific case. Many (most?) variables can be changed with ini_set(), but not all.
2. It might be better to default to cURL and fallback to PHP Streams. If the user does not have cURL installed, obviously, they'll need the fallback. I've never seen anyone complain about not having cURL but lots have complained about not having code that uses it :-p.

Since I was adding an alternative, I kept the current/previous method as the default. I can change this if you think it would be better.

[aensley]

I could see it not being possible to change this at run-time. It's a security-related option, so I doubt it could be changed at runtime. Safe Mode also disables allow_url_fopen, and I'm certain it can't be changed in that situation.

[jpignata]

@aensley Makes sense. Thanks!

[aensley]

Awesome. Thanks!

[aensley]

It worked!

https://travis-ci.org/aensley/YahooStockQuotes/jobs/124034663#L412

[aensley]

You might want to remove this line to reduce output:

curl_setopt($curl, CURLOPT_VERBOSE, true);

I forgot to take that out. Sorry.

https://curl.haxx.se/libcurl/c/CURLOPT_VERBOSE.html