Crawlable Ajax content. SEO-ing without hashbang. Is my way ok? - ajax

I'm going to build my application based on ajax, and my URLs are something like:
http://server.com/module/#function_name,param1,param2...etc
After referencing some discussions about google's suggestion: hashbang (#!), it's not hard for me to realize that it was not the best solution. There are several reasons:
The URL is pretty ugly, anyway.
It's terrible if someday Google(or some other search-engines) suggest a better solution other than hashbang. I must keep my ugly url with hashbang, or write some js-code to make link to my page still alive.
HTML5 pushState will be popular someday.
For all things above, I decide to make it my way: my navigation links will be like this:
<a href="http://server.com/module/for-crawler/function-name/param1/param2/...">
Some text </a>
And some jQuery code will make it capable to load ajax content instead of page-change like a normal link:
$(function(){
$('a').live('click',function(e){
var realURL = translateURL( $(this).attr('href') )
loadContent( realURL );
e.prevetnDefault();
return false;
})
})
/* -- the function translateURL will turn url like :
..... http://server.com/module/for-crawler/function-name/param1/param2/...
Into:
..... http://server.com/module/#function-name/param1/param2/...
That's the real url I think all ajaxers are used to dealing with
*/
When crawler reads my page, it will follow the url in "href" attribute, and I will provide it with static non-js version of my page just for google to read. After some days, my page is indexed & user will see my page on Google's results like this:
http://server.com/module/for-crawler/function-name/param1/param2/...
I'm going to user js again to redirect user to my normal ajax version, I mean, to the real URL :
http://server.com/module/#function-name/param1/param2/...
That's the best approach I can think about at this time. Please give me advices : should I do it that way, or can I make it better ? Thanks all guys !

Depending on your audience I would suggest to use HTML5 PushState anyway.
If the client is not supporting HTML5 PushState let him simply use the same version of your app as the crawlers do. In my opinion a page reload is not as bad as a hashed URL. Since users share URLs your hashed URL gets exposed to other users. This URL wouldn't work for, let's say Facebooks Link sharing previews or any other client that doesn't support JavaScript.
Instead I would only use the crawler-friendly app in combination with HTML5 PushState. With PushState you will always expose a single URL, independent of the JavaScript support of your client.
First, detect whether PushState is supported:
function supports_history_api() {
return !!(window.history && history.pushState);
}
Then your click-handler would look something like this:
$('a').live('click',function(e){
var url = $(this).attr('href');
e.preventDefault();
loadContent( url );
history.pushState({"url":url}, $(this).attr('title'), url);
return false;
})

Related

Single page application with Rails 4 and AngularJS

Ok, this idea might seem quite a bit crazy and it kindo' is (at least for me at my level).
I have a fairly standarad rails app (some content pages, a blog, a news block, some authentication). And I want to make it into a single page app.
What I want to accomplish is:
All the pages are fetched through AJAX like when using turbolinks, except that the AJAX returns only the view part (the yield part in the layout) withought the layout itself, which stays the same (less data in the responces, quicker render and load time).
The pages are mostly just static html with AngularJS markup so not much to process.
All the actual data is loaded separately through JSON and populated in the view.
Also the url and the page title get changed accordingly.
I've been thinking about this concept for quite a while and I just can't seem to come up with a solution. At this point I've got to some ideas on how this actualy might be done along with some problems I can't pass. Any ideas or solutions are greatly appreciated. Or might be I've just gone crazy and 3 small requests to load a page are worse then I big that needs all the rendering done on server side.
So, here's my idea and known problems.
When user first visits the app, the view template with angular markup is rendered regularly and the second request comes from the Angular Resource.
Then on ngClick on any link that adress is sent to ngInclude of the content wrapper.
How do I bind that onClick on any link and how can I exclude certain links from that bind (e.g. links to external authentication services)?
How do I tell the server not to render the layout if the request is comming from Angular? I though about adding a parameter to the request, but there might be a better idea.
When ngInclude gets the requested template, it fires the ngInit functions of the controllers (usually a single one) in that template and gets the data from the server as JSON (along with the proper page title).
Angular populates the template with the received data, sets the browser url to the url of the link and sets the page title to what it just got.
How do I change the page title and the page url? The title can be changed using jQuery, but is there a way through Angular itself?
Again, I keep thinking about some kind of animation to make this change more fancy.
Profit!
So. What do you guys think?
OK, in case enyone ever finds this idea worth thinking about.
The key can be solved as follows.
Server-side decision of whether to render the view or not.
Use a param in the ngInclude and set the layout: false in the controller if that param is present.
Have not found an easier way.
Client-side binding all links except those that have a particular class no-ajax
Here's a directive that does it.
App.directive('allClicks', function($parse) {
return {
restrict: 'A',
transclude: true,
replace: true,
link: function(scope, element, attrs) {
var $a = element.find('a').not($('a.no-ajax')),
fn = $parse(attrs['allLinks']);
$a.on('click', function(event) {
event.preventDefault();
scope.$apply(function() {
var $this = angular.element(event.target);
fn(scope, {
$event: event,
$href: $this.attr('href'),
$link: $this
});
});
});
}
};
})
And then use it on some wrapper div or body tag like <body ng-controller="WrapperCtrl" all-links="ajaxLink($href)"> and then in your content div do <div id="content" ng-include="current_page_template">
In your angular controller set the current_page template to the document.URL and implement that ajaxLink function.
$scope.ajaxLink = function(path) {
$scope.current_page_template = path+"?nolayout=true";
}
And then when you get your JSON with your data from the server don't forget to use history.pushState to set the url line and document.title = to setr the title.

Use Ajax in Prototype.js to load PART of an external page into a div

I'm looking for a way to load a part of an external page (possibly selected by an id in the external page) into a div. Something similar to Ajax.Updater, but with the option of specifying an id to look for in the external page.
Does anything like this exist in prototype. I've been googling for examples without luck. If I can't find it soon I'll have to do some "gymnastics" with Ajax.Request and some function tied to onSuccess.
You could do something like this, though it is by no means an elegant solution.
new Ajax.Updater("container", 'www.babes.com', {
onSuccess: function() {
$("container").update( $('idOfSomeLoadedElement') );
}
});
I don't think there is an actual elegant way of doing this purely in js. Ideally, you'd make your AJAX request only for what you need. You might be able to do some server-side stuff to lop out what you don't need (basically, offload the onsuccess functionality above to the server).
Instead of AJAX you might get by with an iframe.
// dollar function calls Element.extend
var iframe = $(document.createElement('iframe'));
// control how and what it loads
iframe.addEventListener('onLoad', function() {
$('container').update(iframe.contentDocument.select('#someID').first());
});
iframe.setAttribute('src', 'http://URL');
// add it as invisible, content isn't loaded until then
iframe.setAttribute('hidden', true);
document.body.appendChild(iframe);
From a minimal test it's clear that you'll have to be as concious about cross-origin policies as any AJAX method, that is, it's a PITA.

how to get information from php without refreshing the page

hi
sorry for the bad title but I'm not 100% sure what I need for this problem
I created a welcome page and then when you click on links you get more information, for example:
Click Me
And then the php would get the information based on the id.
so the information received is reloaded on the page after the pages refreshes
what I would like to be able to do is when user clicks on the link, use jquery to not allow the link to run but still run the url in the background (without refreshing the page)
I have no idea where to start from so I really hope you could help
thanks
In a nutshell, it's called Ajax: sending an HTTP request to your server through javaScript, and receiving a response which can contain results, data, or other information.
You mention jQuery, here are the docs about that:
http://api.jquery.com/jQuery.get/
http://api.jquery.com/jQuery.post/
are convenience methods, which encapsulate $.ajax with preset options.
http://api.jquery.com/category/ajax/ is an overview of the whole system in jQuery.
The basics go like
//include jquery, etc.
$(document).ready(function(){
$('#some_element').click(function(){
$.get('some_url_on_your_server.php',{'data':'whatever params'},function(data){
do_something();//
},'json');
});
This will bind an element to make an Ajax call on click, and then you use the function ('success' function, in $.ajax) to handle the json data.
Have your server send back the data in JSON by using json_encode in php. Be sure to send the right header back, like
<?php
header('Content-Type: application/json');
echo json_encode($some_array);
exit;
There's a lot of resources on the web and SO for learning about Ajax, it's a big topic. Best of luck.
Make a JavaScript function, like sendData(linkId) and then each tag would have an onclick event called sendData(this). SendData(linkId) can then do an HTTPRequest (also known as an asynchronous or AJAX request) to a php file, let's call it handler.php, which receives GET or POST methods. I prefer using the prototype framework to do this kind of thing (you can get it at prototypejs.org).
Okay, now that I have said all that, let's look into the nitty-gritty of how to do this (way simplified for illustrative purposes).
Download the prototype script, save it on your server (like prototype/prototype.js, for example) and then put somewhere in your html <script type='text/javascript' language='Javascript' src='prototype/prototype.js'></script>
Your tags would look like this:<a id='exampleLink' onclick = 'sendData(this)'>Click me!</a>
You need JavaScript to do this: function sendData(tagId){
var url = 'handler.php?' + 'id=' + tagId;
var request = new AJAX.Request(url, {method = 'get'});
}
Finally, you need a php file (let's call it handler.php) that has the following: <?php
$tag_to_get = $_GET['tagId'];
do_a_php_function($tag_to_get);
?>
That's it in a nutshell, but it's worth mentioning that you should give your user some sort of feedback that clicking link did something. Otherwise he will click the link furiously waiting for something to happen, when it is actually doing just what its supposed to but in secret. You do that by making your php script echo something at the end, like 'Success!', and then add an onSuccess parameter to your JavaScript's new Ajax.Request. I'll let you read how to do that on your own because the prototype website explains how to receive a response from the handler and put the feedback somewhere in your HTML without making the user refresh.
you can achieve that behavior with a jquery function called $.get ... you can get more information on how to use here http://api.jquery.com/jQuery.get/
If you really want to (and I don't think you really do), you can use XMLHTTPRequest (wrapped in jQuery.get) to facilitate loading content into the page without page refreshing. You want an id or class on that tag, i.e. Click Me, and then:
<script>
$(".fetch").bind("click", function(evt)
{
$.get(this.attr("href"), function(data)
{
$("#whereIWantMyContent").html(data);
});
evt.preventDefault();
});
</script>
I would recommend you use AJAX to start with. A good place to being is http://www.w3schools.com/Ajax/Default.Asp
The link comes with a handy AJAX ASP/PHP Example too =))
Good Luck.

Is there a way to AJAX load a page and change URL in URL bar without hashing?

This is probably going to get a resounding no, but I am wondering if it possible to have the URl change dynamically with using hashing, and without invoking a http request from the browser?
My client is keen on using AJAX for main navigation. This is fine, when the end user goes to the front page first, but when they want to use the deep linking, despite it working, it forces an extra load time as the page loads the front page, then invokes the AJAX from the hash.
UPDATE: Could it be possible, given that what I want to avoid is the page reload (the reason is that it looks bad) to stem the reload by catching the hash with PHP before the headers are sent, and redirecting before the page load. This way only one page loads, and the redirect is all but invisible to the user. Not sure how to do this, but seems like it is possible?
Yes, this is possible. I often do this to store state in the hash part of the URL. The result is that the page doesn't reload, but if the user does reload, they're taken to the right page.
Using this method, the URL will look like: "/index#page=home" or "/index#page=about"
You'll need to write a JavaScript function that handles navigation, and you'll need a containing div that gets rewritten with the contents fetched from AJAX.
Home
About
Questions
<div id="content"></div>
<script type="text/javascript">
function link(page) {
location.hash = "page="+page;
loadPage(page);
}
// NOTE: This is using MooTools. Use the AJAX method in whatever
// JavaScript framework you're using.
function loadPage(page) {
new Request.HTML({
url: "/ajax/"+page+".html",
onSuccess: function(tree, elements, html) {
document.id('content').setProperty('html', html);
}
}).get();
}
</script>
Now, you'll also need to have something that checks the hash on page load to load the right content initially. Again, this is using MooTools, but use whatever onLoad method your JavaScript framework provides.
<script type="text/javascript">
document.addEvent('domready', function() {
parts = location.hash.split('=');
loadPage(parts[1]);
}
</script>
Ok, the problem is that opening an AJAX link of the form http://example.com/#xyz results in a full page being downloaded to the browser, and then the AJAX-altered content is changed once the page has loaded and checked the hash part of its URL. The user has a diconcerting experience.
You can hugely improve this by making a page that just contains the static elements - menus, etc. - and a loading GIF in the content area. This page checks its URL upon loading and dynamically fetches the content specified by the hash part. The page can have any URL you want; we'll use http://example.com/a. Links to this page (http://example.com/a#xyz) now provide a good user experience for users with scripting enabled.
However, new users won't come to the site by fetching http://example.com/a; they'll fetch http://example.com. This is fine - serve the full page, including the home page content and links that don't require scripting to work (e.g., http://example.com/xyz). A script run on loading this page should alter the href of AJAXable links to their AJAX form (http://example.com/a#xyz); thus the first link a user clicks on will result in a full page load but subsequent ones won't.
The only remaining problem is is a no-script user gets sent an AJAX link. You can add a noscript block to the AJAX page that contains a message explaining the problem and provides a link back to the homepage; you could include instructions on how to enable scripting or even how to modify the link by removing a# and pressing enter.
It's not a great answer, but you can offer a different link in the page itself; e.g., if the address bar shows /#xyz you include a link to /xyz somewhere in the page. You could also add a link or button that uses script to bookmark the page, which would again use the non-AJAX form of the link.

Pros and cons of AJAX-loaded content

It's pretty nice to sort a dataset by a number of filters and get the results shown instantly, right?
My solution to do this would be to POST the "filter" (read forms) parameters to a page called dataset.php, which returns the appropriate dataset in compiled HTML, that can be loaded straight into my page.
So, besides this being a total no-no for SEO and for people having deactivated Javascript, It appears as a quite good solution to easily build on in the future.
However, I have yet not the experience to consider it a good or bad overall solution. What should be our concerns with an AJAX-fetched dataset?
So, besides this being a total no-no for SEO and for people having deactivated Javascript, It appears as a quite good solution to easily build on in the future.
Not entirely true, there are solutions out there like jQuery Ajaxy which enable AJAX content with History tracking while remaining SEO and javascript disabled friendly. You can see this in action on my own site Balupton.com with evidence it's still SEO friendly here.
However, I have yet not the experience to consider it a good or bad overall solution. What should be our concerns with an AJAX-fetched dataset?
Having Ajax loaded content is great for the user experience it's fast quick and just nice to look at. If you don't have history tracking then it can be quite confusing especially if you are using ajax loaded content for things like pages, rather than just sidebar content - as then you break away from consistency users are experienced with. Another caveat is Google Analytics tracking for the Ajax pages. These shortcomings, those you've already mentioned as well as some others mentioned elsewhere are all quite difficult problems.
jQuery Ajaxy (as mentioned before) provides a nice high level solution for nearly all the problems, but can be a big learning curve if you haven't worked with Controller architecture yet but most people get it rather quickly.
For instance, to enable history trackable ajax content for changing a set of results using jQuery Ajaxy, you don't actually need any server side changes. You could do something like this at the bottom of your page: $('#results ul.pages li.page a').addClass('ajaxy ajaxy-resultset').ajaxify();
Then setup a Ajaxy controller like so to fetch just the content we want from the response:
'resultset': {
selector: '.ajaxy-resultset',
request: function(){
// Hide Content
$result.stop(true,true).fadeOut(400);
// Return true
return true;
},
response: function(){
// Prepare
var Ajaxy = $.Ajaxy; var data = this.State.Response.data; var state = this.state;
// Show Content
var Action = this;
var newResultContent = $(data.content).find('#result').html();
$result.html(newResultContent).fadeIn(400,function(){
Action.documentReady($result);
});
// Return true
return true;
}
}
And that's all there is too it, with most of the above being just copy and pasted code from the demonstration page. Of course this isn't ideal as we return the entire page in our Ajax responses, but this would have to happen anyway. You can always upgrade the script a bit more, and make it so on the server side you check for the XHR header, and if that is set (then we are an ajax request) so just render the results part rather than everything.
You already named the 2 big ones. Now all you need to do is make sure all the functionality works without javascript (reload the page with the requested dataset), and use AJAX to improve it (load the requested dataset without reloading the page).
This largely depends on the context. In some cases people today may expect the results to be delivered instantly without the page refreshing itself. It does also improve overall user-experience - again, this largely depends on the context.
However, it does also have its pitfalls. Would the user have a need to return to the previous pages after the ajax content was delivered? Since this may not be as simple as pressing the Back button in the browser.

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