Detect OGP tags
// https://developer.apple.com/library/ios/documentation/General/Conceptual/ExtensibilityPG/ExtensionScenarios.html#//apple_ref/doc/uid/TP40014214-CH21-SW12
var MyExtensionJavaScriptClass = function() {};
MyExtensionJavaScriptClass.prototype = {
run: function(arguments) {
// selection string
var selectionString = window.getSelection().toString();
// open graph
var ogMetas = {};
var metatags = document.getElementsByTagName("meta");
if(0 < metatags.length) {
for (i = 0; i < metatags.length; i++) {
var property = metatags[i].getAttribute("property");
var content = metatags[i].getAttribute("content");
if( "og:title" == property) {
ogMetas.title = content;
}
else if( "og:description" == property) {
ogMetas.description = content;
}
else if( "og:site_name" == property) {
ogMetas.site_name = content;
}
else if( "og:url" == property) {
ogMetas.url = content;
}
else if( "og:type" == property) {
ogMetas.type = content;
}
else if ( "og:image" == property ||
"og:image:url" == property ||
"og:image:secure_url" == property ){
var image = {"url": content};
for (var j=i+1; j<metatags.length; j++) {
var imageProperty = metatags[j].getAttribute("property");
var imageContent = metatags[j].getAttribute("content");
if("og:image:width" == property) {
image.width = imageContent;
i = j;
}
else if("og:image:height" == property) {
image.height = imageContent;
i = j;
}
if(3 <= image.length) {
break;
}
}
if(undefined === ogMetas.image) {
ogMetas.image = [image];
}
else {
ogMetas.image[ogMetas.image.length] = image;
}
}
}
}
arguments.completionFunction({
"baseURI": document.baseURI,
"selectionString": selectionString,
"ogMetas": ogMetas,
});
},
// Note that the finalize function is only available in iOS.
finalize: function(arguments) {
// arguments contains the value the extension provides in [NSExtensionContext completeRequestReturningItems:completion:].
// In this example, the extension provides a color as a returning item.
// document.body.style.backgroundColor = arguments["bgColor"];
}
};
// The JavaScript file must contain a global object named "ExtensionPreprocessingJS".
var ExtensionPreprocessingJS = new MyExtensionJavaScriptClass();