====== PHP RFC: Slim POST data ======
  * Version: 1.3
  * Date: 2013-12-17
  * Author: Michael Wallner <mike@php.net>
  * Status: Accepted
  * First Published at: https://wiki.php.net/rfc/slim_post_data

===== Introduction =====

A memory usage improvement regarding receiving HTTP payloads with a potential reduction of 200-300%.

===== Proposal =====

This change replaces the SAPI layer's (raw_)post_data entries with a temporary PHP stream. 

If the request was a standard www-form-urlencoded or form-data POST, everything is just as it was before. 

If the request had another request method or an unrecognized content type, the payload is available through the re-usable, just-in-time %%php://input%% stream.

===== Proposed PHP Version(s) =====

Next 5.x, i.e. 5.6

===== SAPIs Impacted =====

Web-SAPIs.

===== Unaffected PHP Functionality =====

Standard form POSTs and file uploads.

===== Changes to PHP-5.6 =====

  * Re-usable, optioanlly JITty initialized %%php://input%% stream
  * Change always_populate_raw_post_data INI setting to accept three values instead of two.
    * -1: The behavior of master; don't ever populate %%$GLOBALS[HTTP_RAW_POST_DATA]%%
    * 0/off/whatever: BC behavior (populate if content-type is not registered or request method is other than POST)
    * 1/on/yes/true: BC behavior (always populate %%$GLOBALS[HTTP_RAW_POST_DATA]%%)

===== Backward Incompatible Changes to master =====

$HTTP_RAW_POST_DATA and always_populate_raw_post_data were removed.

BC can be restored with:

<code php>
$GLOBALS["HTTP_RAW_POST_DATA"] = file_get_contents("php://input");
</code>

===== Impact to Existing Extensions =====

Extensions utilizing %%SG(request_info).(raw_)post_data(_len)%%.

In case of mbstring, the fix was as simple and ineffective as:
<code diff>
@@ -376,7 +377,10 @@ SAPI_POST_HANDLER_FUNC(php_mb_post_handler)
        info.num_from_encodings     = MBSTRG(http_input_list_size); 
        info.from_language          = MBSTRG(language);
 
-       detected = _php_mb_encoding_handler_ex(&info, arg, SG(request_info).post_data TSRMLS_CC);
+       php_stream_rewind(SG(request_info).request_body);
+       php_stream_copy_to_mem(SG(request_info).request_body, &post_data_str, PHP_STREAM_COPY_ALL, 0);
+       detected = _php_mb_encoding_handler_ex(&info, arg, post_data_str TSRMLS_CC);
+       STR_FREE(post_data_str);
</code>

===== Future Scope =====

The SAPI layer might be improved for SAPIs to provide their own PHP stream for POST data implementation, instead of soaking everything into the temp stream.

===== Proposed Voting Choices =====

  * Yes
  * No

===== Patches and Tests =====

To see the changes already in master, do, more or less:

<code shell>
git diff 1c15d70^..e6084da
</code>

http://git.php.net/?p=php-src.git;a=commitdiff;h=e6084da4735c945cb071c4d9259ea0d702eb77c6;hp=52ff129607a7193cccbc6bdfbf1c1e8586e8d0d2

Always_populate_raw_post_data patch is available here:

https://github.com/m6w6/php-src/compare/php:PHP-5.6...always_populate_raw_post_data

===== References =====

  * http://marc.info/?t=137760545600006&r=1&w=2
  * http://marc.info/?l=php-internals&m=138303606829213&w=2
  * http://marc.info/?t=138449998700002&r=1&w=2

===== Changes =====

  * 1.1
    * Added PHP-5.6 patch to re-introduce always_populate_raw_post_data (-1/0/1)
  * 1.2
    * Re-ordered the RFC and reworded some sections.
  * 1.3
    * Accepted.

===== Vote =====
<doodle title="RFC/slim_post_data" auth="mike" voteType="single" closed="true">
   * Yes
   * No
</doodle>