Batch.run

From Facebook Developers Wiki

Contents 1 Description 2 Parameters 3 Example Return XML 4 Response 5 FQL Equivalent 6 Error Codes 7 Notes

[edit] Description

Execute a list of individual API calls in a single batch.

Batch API allows you to combine multiple individual operations into a single request. This could reduce the traffic load to Facebook server and latency substantially. To see more information about using batching API, please read Using batching API.

Note that there is maximum limit of 20 individual operations that can be performed in a single batch execution.

[edit] Parameters

Required	Name	Type	Description
required	api_key	string	The application key associated with the calling application.
	session_key	string	The session key of the logged in user.
	call_id	float	The request's sequence number. Each successive call for any session must use a sequence number greater than the last. We suggest using the current time in milliseconds, such as PHP's microtime(true) function.
	sig	string	An MD5 hash of the current request and your secret key, as described in the authentication guide.
	v	string	This must be set to 1.0 to use this version of the API.
	method_feed	string	A JSON encoded array of strings. Each element in the array should contain the full parameters for a method, including method name, sig, etc. Currently, there is a maximum limit of 15 elements in the array.
optional	serial_only	bool	An optional parameter to indicate whether the methods in the method_feed must be executed in order. The default value is false.
	format	string	Desired response format. Either XML (default) or JSON.
	callback	string	Name of a function to call. This is primarily to enable cross-domain javascript requests using the <script> tag, sometimes known as "JSONP". This works with both XML and JSON.

[edit] Example Return XML

<?xml version="1.0" encoding="UTF-8"?> <batch_run_response xmlns="http://api.facebook.com/1.0/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://api.facebook.com/1.0/ http://api.facebook.com/1.0/facebook.xsd" list="true"> <batch_run_response_elt>&lt;?xml version=&quot;1.0&quot; encoding=&quot;UTF-8&quot;?&gt; &lt;friends_get_response xmlns=&quot;http://api.facebook.com/1.0/&quot; xmlns:xsi=&quot;http://www.w3.org/2001/XMLSchema-instance&quot; xsi:schemaLocation=&quot;http://api.facebook.com/1.0/ http://api.facebook.com/1.0/facebook.xsd&quot; list=&quot;true&quot;&gt; &lt;uid&gt;1160&lt;/uid&gt; &lt;/friends_get_response&gt; </batch_run_response_elt> </batch_run_response>

[edit] Response

An array of individual results as strings.

[edit] FQL Equivalent

There is no equivalent FQL query.

[edit] Error Codes

Code	Description
1	An unknown error occurred. Please resubmit the request.
2	The service is not available at this time.
4	The application has reached the maximum number of requests allowed. More requests are allowed once the time window has completed.
5	The request came from a remote address not allowed by this application.
100	One of the parameters specified was missing or invalid.
101	The API key submitted is not associated with any known application.
102	The session key was improperly submitted or has reached its timeout. Direct the user to log in again to obtain another key.
103	The submitted call_id was not greater than the previous call_id for this session.
104	Incorrect signature.
950	Each batch API cannot contain more than 20 items.

[edit] Notes

The method_feed parameter is a JSON-encoded array of strings. Each string contains all the parameters for each individual API call, such as session_key, api_key and sig.

For example, suppose you want to send a batch API request to execute friends.get and notifications.get. First, you would construct all the parameters for friends.get and notifications.get and place them into an array of strings, like this:

["method=friends.get&session_key=abcd&api_key=abcd&format=JSON&call_id=717&v=1.0&sig=0123", "method=notifications.get&session_key=abcd&api_key=abcd&format=JSON&call_id=717&v=1.0&sig=0123"]

Now you can use your favorite JSON encoding function to encode the array into a JSON string, and use it as the value of the method_feed parameter, like this:

method_feed=%5B%22method%3Dfriends.get%26session_key%3abcd ... 22method%3Dnotifications.get%26session_key%abcd ..."