ContentProxy

Most browsers don’t allow XMLHttpRequest to retrieve data from domains other than the domain where the script was fetched from, as shown in the diagram below.

Because of this security restriction, Pageflakes provides a content proxy server that can be used to fetch data from other domains. To do this, the flake makes a request to the proxy server. The proxy server then retrieves the content and returns it to the browser, as shown below.

The Content Proxy provides several methods:

ContentProxy.GetUrl(url, F(this, callbackFunction)) ContentProxy.FormPost(url, values, F(this, callbackFunction)) ContentProxy.UploadString(url, "content as string which is POSTed", F(this, callbackFunction));

If the call is successful, the content proxy invokes a function that was passed to it as callback.

The ContentProxy is set to cache any retrieved data for 10 minutes (GET calls only). Successive calls with the same parameters use the cached data rather than re-fetching the data from the remote server. This action optimizes flake performance. However, if updated data is required before the 15 minute interval, the GetURL or FormPost methods cannot be used.

Non-cached results can be retrieved using ContentProxy.getUrlNonCached(). The parameters are the same as ContentProxy.GetUrl().

HTTP GET Example

This code demonstrates the use of HTTP GET with the ContentProxy object:
ContentProxy.GetUrl("http://xml.example.com/", F(this, callback), onerror);

function callback(result) { // result is a string that can be used as needed } function onerror(exception) { }

HTTP POST Example

This example demonstrates how to pass POST parameters when using the ContentProxy object.
POSTData = {}; POSTData.parameter1 = "Some data"; POSTData.parameter2 = "Some more data"; ContentProxy.FormPost(url, POSTData, F(this, callback), onerror); Alternatively, the following is also acceptable: ContentProxy.FormPost(url, { parameter1 : “Some data”, parameter2 : “some more data” }, F(this, callback));

ContentProxyResponse

The ContentProxyResponse object is used by several of the ContentProxy functions to return headers and cookies, in addition to the returned content. This object has three properties:

Property	Description
`Content`	A string containing the content returned by the HTTP operation.
`Header`	An array of objects, each representing an HTTP header. Each object has two properties: "Key" and "Value". "Key" is a string representing the name of the header, and “Value” is a string representing the value of the header.
`Cookie`	An array of objects, each representing a cookie. Each object has two properties: "Key" and "Value". "Key" is a string representing the name of the cookie, and "Value" is a string representing the value of the cookie.

Header = [ { Key: “Content-Type” , Value: “foo”}, {Content-Length, “bar”] ]

GetUrl

Method signature	`ContentProxy.GetUrl(url,succeededCallback, failedCallback)`
Input Parameters	`url`	The URL of the target location.
	`succeededCallback`	The function to invoked when the operation succeeds
	`failedCallback`	The function to be invoked if the operation fails
Callback Parameter	Content of HTTP response as string.
Notes	The response is cached for 10 minutes.

GetUrl1

Method signature	`ContentProxy.GetUrl1(url, cacheDurationInMinutes, succeededCallback, failedCallback)`
Input Parameters	`url`	The URL of the target location.
	`cacheDurationInMinutes`	Specifies how long the response is cached on the server.
	`succeededCallback`	The function that is invoked when the operation succeeds.
	`failedCallback`	The function that is invoked if the operation fails.
Callback Parameter	Content of the HTTP response as string.
Note	The response is cached for the specified duration.

GetUrl2

Method signature	`ContentProxy.GetUrl2(url, headers, succeededCallback, failedCallback)`
Input Parameters	`url`	The URL of the target location.
	`headers`	An array of headers used to create the request object. Each header object is a one-dimensional array having two elements. The first element is the name of the header and the second one is its value. For example: `[ ["Content-Type","text/plain"], ["X-MyHeader","foo"] ]`
	`succeededCallback`	The function that is invoked when the operation succeeds.
	`failedCallback`	The function that is invoked if the operation fails.
Callback Parameter	Content of HTTP response as string.
Note	The response is cached for 10 minutes.

GetUrl3

Method signature	`ContentProxy.GetUrl3(url, headers, cookies, succeededCallback, failedCallback)`
Input Parameters	`url`	The URL of the target location.
	`headers`	An array of headers used to create the request object. Each header object is a one-dimensional array having two element. The first element is the name of the header and the second one is its value. For example: `[ ["Content-Type","text/plain"], ["X-MyHeader","foo"] ]`
	`cookies`	An array of cookies used to create the request object. Each cookie object a one-dimensional array having two elements. The first element is name of the cookie and the second one is its value. For example: `[ ["session-id","1234"], ["other-cookie","foo"] ]`
	`succeededCallback`	The function that is invoked when the operation succeeds.
	`failedCallback`	The function that is invoked if the operation fails.
Callback Parameter	A `ContentProxyResponse` object.
Note	The response is cached for 10 minutes.

GetUrlNonCached

Method signature	`ContentProxy.GetUrlNonCached(url,succeededCallback, failedCallback)`
Input Parameters	`url`	The URL of the target location.
	`succeededCallback`	The function that is invoked when the operation succeeds
	`failedCallback`	The function that is invoked if the operation fails
Callback Parameter	Content of HTTP response as string
Note	The response will not be cached.

GetUrlNonCached2

Method signature	`ContentProxy.GetUrlNonCached2(url, headers, cookies, succeededCallback, failedCallback)`
Input Parameters	`url`	The URL of the target location.
	`headers`	An array of headers used to create the request object. Each header object is a one-dimensional array having two elements. The first element is the name of the header and the second one is its value. For example: `[ [“Content-Type”,“text/plain”], [“X-MyHeader”,“foo”] ]`
	`cookies`	An array of cookies used to create the request object. Each cookie object a one-dimensional array having two elements. The first element is name of the cookie and the second one is its value. For example: `[ [“session-id”,“1234”], [“other-cookie”,“foo”] ]`
	`succeededCallback`	The function that is invoked when the operation succeeds.
	`failedCallback`	The function that is invoked if the operation fails.
Callback Parameter	A `ContentProxyResponse object.`
Note	The response is not cached.

FormPost

Method signature	`ContentProxy.FormPost(url, parameters, succeededCallback, failedCallback)`
Input Parameters	`url`	The URL of the target location.
	`parameters`	Parameters that are passed with a given URL. The parameters object basically is a dictionary which contains the parameters name and value as key-value pair.
	`succeededCallback`	The function that is invoked when the operation succeeds.
	`failedCallback`	The function that is invoked if the operation fails.
Callback Parameter	The content of the HTTP response as a string.
Note	`FormPost` method performs an HTTP POST operation.

FormPost2

Method signature	`ContentProxy.FormPost2(url, parameters, headers, succeededCallback, failedCallback)`
Input Parameters	`url`	The URL of the target location.
	`parameters`	Parameters that are passed with the given URL. The parameters object is a dictionary which contains the parameters name and value as a key-value pair.
	`headers`	An array of headers used to create the request object. Each header object is a one-dimensional array with two elements. The first element is the name of the header and the second is its value. For example: `[ ["Content-Type","text/plain"], ["X-MyHeader","foo"] ]`
	`succeededCallback`	The function that is invoked when the operation succeeds.
	`failedCallback`	The function that is invoked if the operation fails.
Callback Parameter	The content of the HTTP response as a string.
Note	FormPost2 method performs an HTTP POST operation.

FormPost3

Method signature	`ContentProxy.FormPost2(url, parameters, headers, cookies, succeededCallback, failedCallback)`
Input Parameters	`url`	The URL of the target location.
	`parameters`	The parameters passed to the given url. The parameters object basically is a dictionary which contains the parameter’s name and value as a key-value pair.
	`headers`	An array of headers used to create the request object. Each header object is a one-dimensional array having two elements. The first element is the name of the header and the second one is its value. For example: `[ ["Content-Type","text/plain"], ["X-MyHeader","uoo"] ]`
	`cookies`	An array of cookies used to create the request object. Each cookie object is a one-dimensional array having two elements. The first element is the name of the cookie and the second one is its value. For example: `[ [“session_id”,“abc123”], [“cart_status”,“foobar”] ]`
	`succeededCallback`	The function that is invoked when the operation succeeds.
	`failedCallback`	The function that is invoked if the operation fails.
Callback Parameter	Content of HTTP response as string.
Note	FormPost2 method performs an HTTP POST operation.

UploadString

Method signature	`ContentProxy.UploadString(url, requestData, succeededCallback, failedCallback)`
Input Parameters	`url`	The URL of the target location.
	`requestData`	Data to be POSTed
	`succeededCallback`	The function that is invoked when the operation succeeds.
	`failedCallback`	The function that is invoked if the operation fails.
Callback Parameter	Content of HTTP response as string.
Note	UploadString method performs HTTP POST operation and uploads the raw string to the specified URL. Useful for making SOAP calls.

UploadString2

Method signature	`ContentProxy.UploadString2(url, headers, requestData, succeededCallback, failedCallback)`
Input Parameters	`url`	The URL of the target location.
	`headers`	An array of headers used to create the request object Each header object is a one-dimensional array with two elements. The first element is the name of the header and the second one is its value. For example: `[ ["Content-Type","text/plain"], ["X-MyHeader","foo"] ]`
	`requestData`	Data to be POSTed
	`succeededCallback`	The function that is invoked when the operation succeeds.
	`failedCallback`	The function that is invoked if the operation fails.
Callback Parameter	Content of HTTP response as string.
Note	`UploadString2` performs an HTTP POST operation.