Consuming & embedding external content in WordPress presented by me at WordCamp Mumbai 2015 #WCMumbai

1. Consuming & embedding
external content
Akshay Raje

2. @akshayraje
profiles.wordpress.org/akshay_raje
WordPress
jQuery
Human Resources
Biking
PHPJavaScript

3. $topics = array(
'HTTP requests in PHP/WordPress',
'Helper functions: GET, POST, HEAD',
'Request arguments',
'Caching: Object Caching and Transients API',
'Parsing',
'How WP Web Scraper helps'
);
if( in_array( $question, $topics ) !== true )
var_dump( $question );
Next 25 minutes:
@akshayraje

4. 0: HTTP Requests in
PHP/WordPress
@akshayraje

5. Multiple Transports, Functions,
Environments
cURL
file_get_contents
fsockopen
Shared
Dedicated
VPS
IaaS
PaaS
fopenhttp
streams

6. Before AfterWord
2
Press
7
• Design & support own
implementation
• Branch code for multiple
transport implementations
• Duplication of code across
plugins
• Standard API for core and
plugins
• Wider environment support
with fallbacks
• OO and helper Functional
@akshayraje

7. 1: Helper functions: GET, POST,
HEAD
@akshayraje

8. wp_remote_get() Retrieves a URL using the GET
HTTP method.
wp_remote_post() Retrieves a URL using the POST
HTTP method.
wp_remote_head() Retrieves a URL using the HEAD
HTTP method.
wp_remote_request() Retrieves a URL using either the
default GET or a custom HTTP
method that you specify.
WP_HTTP Helper functions
@akshayraje

9. $url (string) (required) Site URL to retrieve.
Default: None
$args (array) (optional) Override the defaults.
Default: array()
WP_HTTP Helper functions
Parameters
Return Values
(WP_Error|array) The response or WP_Error on failure.
@akshayraje

10. $response = wp_remote_get( 'http://httpbin.org/html' );
if ( is_wp_error( $response ) ) {
echo 'Something went wrong: ' . $response-
>get_error_message();
} else {
print_r( $response );
}
<?code
@akshayraje

11. @akshayraje
<?output
@akshayraje

12. 2: Request arguments
@akshayraje

13. @akshayraje
Default $args

14. @akshayraje
$args = array(
'timeout' => 10,
'user-agent' => 'My-Bot',
'body' => array( 'username' => 'bob', 'password' => '1234xyz' )
);
$response = wp_remote_post( 'http://httpbin.org/post', $args );
if ( is_wp_error( $response ) ) {
echo 'Something went wrong: ' . $response->get_error_message();
} else {
print_r( $response );
}
<?code POST example

15. 3: Caching: Object Cache and
Transients API
@akshayraje

16. Why Cache?
API Rate Limits
Blocking requests
Outgoing bandwidth
Avoid abusing web service
Page Load
No change in content
PaaS Rate Limits

17. What Cache?
Object Cache
Page Cache
@akshayraje

18. What Cache?
Object Cache
Persistent
Page Cache
@akshayraje

19. Object Cache
Persistent
W3 Total Cache
WP Super Cache
Quick Cache
Hyper Cache
WP Fastest Cache
Disk
APC
eAccelerator
XCache
WinCache
Memcached
@akshayraje

20. Object Cache
Persistent
Transients API
‘guarantees’
@akshayraje

21. Use the Transients API instead of
wp_cache functions if you need to
guarantee that your data will be cached. If
persistent caching is configured, then the
transients functions will use the wp_cache
functions. However if persistent caching
has not been enabled, then the data will
instead be cached to the options table.
Source: http://codex.wordpress.org/Class_Reference/WP_Object_Cache
“
@akshayraje

22. @akshayraje
$transient (string) (required) Unique transient name.
45 characters or less in length.
Default: None
Transients functions
get_transient( $transient )
Pretty much like get_option( $option )

23. @akshayraje
Transients functions
set_transient($transient, $value, $expiration)
Pretty much like set_option( $option, $value )
$transient (string) (required) Unique transient name.
45 characters or less in length.
Default: None
$value (mixed) (required) Transient value.
Default: None
$expiration (int) (optional) Time until expiration in
seconds from now, or 0 for never expires.
Default: 0.

24. @akshayraje
// Get any existing copy of transient data if available
if ( false === ( $response = get_transient( 'special_wp_remote_get' ) ) ) {
$response = wp_remote_get( 'http://httpbin.org/html' );
if ( !is_wp_error( $response ) ) {
set_transient( 'special_wp_remote_get', $response, 12 *
HOUR_IN_SECONDS );
}
}
// Use $response like you would have normally...
<?code Cached wp_remote_get

25. 4: Parsing
@akshayraje

26. <?output
@akshayraje

27. wp_remote_retrieve_body() Retrieves just the body from the
response.
wp_remote_retrieve_header() Gives you a single HTTP header
based on name from the
response.
wp_remote_retrieve_headers() Returns all of the HTTP headers
in an array for processing.
wp_remote_retrieve_response_code() Gives you the number for the
HTTP response. This should be
200, but could be 4xx or even
3xx on failure.
wp_remote_retrieve_response_message() Returns the response message
based on the response code.
WP_HTTP Helper functions
@akshayraje

28. JSON Native Object
json_decode
XML XPath
DOMDocument class
HTML XPath
DOMDocument class
Parsing
@akshayraje

29. 5: WP Web Scraper
wp-ws.net
wordpress.org/plugins/wp-web-scrapper
@akshayraje