Based on my custom URL parameters I process, I am trying to modify dynamically a meta tag I have id'ed in index.html like so:
<meta name="og:image" content="http://example.com/someurl.jpg" id="ogImage"/>
The code below in my home.ts seems to be working
document.getElementById('ogImage').setAttribute("content", Media.ImageURL) ;
I can verify it is via the browser dev console/elements.
However, when I view from facebook via their ojbect graph debugger at
https://developers.facebook.com/tools/debug/og/object/
It appears to see the default
http://example.com/someurl.jpg
as if the index.html is shipped before my home.ts gets chance to make the update.
Perhaps, my understanding is flawed and there is better way to do this.
Thank you.
Note1: initially, I was thinking I had to make some angular binding between index.html and one of my services but I could not locate any sample code, the closest I came to was this post
How can I update meta tags in AngularJS?
But I don't know how to apply it for my ionic2/3 code, so I opted for the document.get approach.
Note2: the ultimate goal here is to share a link into a social media (web or app) like facebook, a messenger like viber/skype, etc... and have it resolve to meaningful images, title, description to drive the visit back to the site via browser, or app if the user clicking on the link is on a mobile device with my app version of the site installed on his device.
Note3: if you decide to point me to ionic deeplinking please provide code to match above, because I could not understand how to apply to my case.
If you are trying to implement dynamic open graph meta tags values in your pages, you will need a server-side scripting language like php. Such a script will run on the server, update the pages as needed, then the pages will be served to the requesting site or application.
client-side scripting (ie. JavaScript) is usually ignored when a site or app is merely visiting your site/link for the purpose of extracting (aka scrapping, parsing html) information such as the one provided by the open graph meta tags (og:title, og:description og:image...).
Related
MDN docs state:
To enable a web page to contain an <img> element whose src attribute points to this image,
you could specify "web_accessible_resources" like this:
"web_accessible_resources": ["images/my-image.png"]
The file will then be available using a URL like:
moz-extension://<extension-UUID>/images/my-image.png"
<extension-UUID> is not your extension's ID.
It is randomly generated for every browser instance.
This prevents websites from fingerprinting a browser by examining
the extensions it has installed.
So, I would think that these resources cannot be read by any web page outside the extension, since they would need to know the random UUID.
However, the same MDN docs also state:
Note that if you make a page web-accessible, then any website may then link or redirect
to that page. The page should then treat any input (POST data, for examples)
as if it came from an untrusted source, just as a normal web page should.
I don't understand how "any website may then link or redirect to that page". Wouldn't it need to know the random UUID? How else could a webpage access this resource?
The point of Web Accessible Resources is to be able to include them in a web context.
While you can communicate the random UUID to the webpage so that it can use the file, it doesn't have to be included by the website code itself. Here's a hypothetical scenario:
You're writing an extension that adds a button to evil.com site's UI. That button is supposed to have an image on it.
You bundle the image with your extension, but to add it as src or CSS property to the webpage you need to be able to reference it from a web context.
So, you make it web-accessible, and then inject your UI element with a content script.
Perfectly plausible scenario.
Note that a random third-party site villains-united.com can't just scrape the URL to know if your extension is installed, since the URL is per-browser unique. This is the intent behind WebExtensions's UUID over Chrome's extension-id model.
However, let's continue our hypothetical scenario, from a security perspective.
The operators of evil.com are unhappy with your extra UI. They add a script to their code that looks for added buttons.
That script can see the DOM properties of the button, including the address of the image. Now evil.com's code can see your UUID.
Being the good guy, your extension's source code is available somewhere, including the page that launches nuclear missiles if called (why you would have that and why it would be web-accessible is another matter, perhaps to provide the functionality to good-guys-last-resort.org).
evil.com's script now can reconstruct the URL of this trigger page and XHR it, plunging the planet into nuclear apocalypse. Oops. You probably should've checked the origin of that request.
Basically, if a web-accessible resource is used in a page, the UUID likely leaks to that page's context via DOM. That may not be a page you control.
I'm working on an Angular (1.6.8) app in which we've implemented the Angulartics library in combination with Google Analytics and Google Tag Manager extensions. This is all working quite well when I follow the instructions that are provided.
But we seem to have a bit of a special situation, the application that we're building is going to be used by multiple people, and based on who is visiting we fetch user settings from our api (using url parameters to know who is visiting at that time).
These users can manage their settings in a different Angular app, it's in this second app that they provide us with they Tag Manager tag, and their Analytics code.
Now comes the hard part (for me at least), Google Tag Manager requires a script tag in the head of our html, but at that time the user settings have not been loaded from our api yet, so we can't provide Google's script with the correct Tag Manager tag (this format: GTM-XXXXX).
Does anyone know of a way to load these scripts correctly when we have dynamically loaded tracking codes? Or is this just not possible?
Thanks for anyone who can provide some insights.
Alright it's been a while and I've figured out a solution that does the job (a while ago), I'll display how I got there in case someone else stumbles upon my question.
It ended up being quite simple, I have the following in my html
<!-- Google Tag Manager -->
<script ng-bind-html="googleTagManagerScript"></script>
<!-- End Google Tag Manager -->
And then in my app.js I fetch the settings through an ajax call and when I have the results I do the following
$rootScope.pixels.tagmanager = value; // store the retrieved Tag Manager code in a variable
$rootScope.googleTagManagerScript = $sce.trustAsHtml("(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','"+$rootScope.pixels.tagmanager.code+"');");
$rootScope.googleTagManagerNoScript = $sce.trustAsHtml("<iframe src='https://www.googletagmanager.com/ns.html?id="+$rootScope.pixels.tagmanager.code+"' height='0' width='0' style='display:none;visibility:hidden'></iframe>");
So basically I put the entire Google script in a variable as soon as everything is available, and ng-bind-html takes care of the rest.
I hope that makes sense.
I have a personal project which consumes my free time and effort for about a year without significant profit. I have problems with it appearance in Google and would really appreciate to get help here.
This project (http://yuppi.com.ua - similar to craiglist in US) is WEB-based AngularJS 1.2 application that uses PHP rest API hosted on GoDaddy. And in order to make this application popular it have to be very visible in internet and very searchable in Google and users have to be able to share pages via social networks or skype.
According to Google specification, google crawlers doesn't run javascript to get content of a web page before index, so I've added _escaped_fragment_ page that displays content of web page without javascript. For example:
Page: http://yuppi.com.ua/#!/items/sub/18/_
Dirty : yuppi.com.ua/?_escaped_fragment_=/items/sub/18/_
This dirty page will be redirected here where google will see content.
http://yuppi.com.ua/server/crawler_proxy/routee.php?path=/items/sub/18/
So basically I have two versions on HTML file for that page. One version is the one that available to users, which has styles, a lot more HTML tags etc. And the second is the version for Google crawler - very light-weight without any styles. And I am expecting to see clean link to my site in Google, not dirty.
So, If to search all links to a web site in Google you will see that one of the links displays it's "dirty" state.
Another problem is sharing links in Skype.
When I send a link to someone, I am expecting that this link will be transformed to thumbnail image but it is not happens. Instead I see ungly link to my web site.
Please help me to understand how to make happy everyone: users, google crawler, GoDaddy and me.
I was encountering the same problems last year with a big project and we ended to use : https://prerender.io/.
It's a prerendering system that work with a phantomjs browser to detect bot request and render a full html template. It does also instanciate a cache service to not render again a template that haven't change.
Hope it help's.
I am using the Polymer Starter Kit to build a small website. However I have run into a problem. I am wanting to serve up Word documents. The usual way is to place these in an anchor tag eg
Session Notes
However this is captured as a page to load by Polymer and produces the 404 page, though the url on the page is correct. When I refresh the page, the document is served up normally.
How can I adjust the starter kit, especially the _pageChanged function so that there is no page change and the normal process of simply serving the document is followed.
Edit:
I have solved the problem, however not using anchor tags. I created a small form component with simply a button. In the form I have two fields which become attributes, one for the form action attribute and one for the button text. This means that in my pages I simply call this component with two attributes
<form-button submit="Button text" action="file location"></form-button>
While not the most elegant solution it has the desired effect.
The easiest way would be to find a CDN or use a Cloud-based solution. You could, for example, use Google Drive and find a sharelink to direct link converter and have it served externally.
Another method, harder, would be to set up another web server on a different port. For example, NGINX running on Port 80, with the PSK running, and Apache running on port 81, serving your Word Documents. Not as convenient, but it would work.
I am trying to create buttons on a web page that allow users to share links to PDF documents on LinkedIn. LinkedIn loads a window without any errors but offers no link or preview of the PDF or any indication of what is being shared.
Here are the two methods I have tried. First the plugin method.
<script type="in/share" data-url="http://example.net/DocumentDownload.aspx?Command=Core_Download&entryID=114"></script>
And, secondly with a custom url.
TEST
Encoding the url makes no difference.
The above links are direct document links from a DNN web site using Document Exchange. If I change the urls to any html page it works fine and LinkedIn seems to be able to extract the useful information right from the page and use that for the share details.
Can LinkedIn handle this kind of thing? There is nothing to guide me on the type of links that can be shared. I can't find any information about it. There are no errors in the web console.
Not sure, but you should try to provide LinkedIn with the link that has .pdf at the end, like http://example.com/documents/file1.pdf. I guess LinkedIn just checks the URL if it has .pdf file at the end to decide if it is a PDF document or not.
I have no problem sharing pdf's on LinkedIn. Check it out...
https://www.linkedin.com/sharing/share-offsite/?url=https://www.revoltlib.com/anarchism/the-conquest-of-bread/view.pdf
Works perfectly fine. And view.pdf is a script, not a file, either, so, it's not looking for a PDF file to analyze, so much as headers that indicate you have a PDF file available to analyze, so, in PHP, at DocumentDownload.aspx, we would do...
header('Content-type: application/pdf; charset=utf-8');
This header let's the sharing app know that it can analyze the document as a PDF file and extract useful information from it, as you can see from the screen shot.