When posting a link directly to a Tab on a Facebook Page,
https://www.facebook.com/PAGENAME?sk=app_APPID
Facebook picks up the Page's Open Graph <meta> tags, which means the link post gets associated with the Page's profile picture, name, and a description of "Page • n like this".
I had hoped that Facebook would instead use the og <meta> tags from the app's HTML, allowing link posts to be customized.
What's the best way to provide a direct link to a specific Tab on a Facebook Page with custom content in the link post?
The best way I can see to have this accomplished would be to have a redirector page hosted on a website (www.example.com/fb/redirectorForApp.html) that does a redirect on a javascript timeout. That redirector page has the og tags you want to have specified. The redirect will land the person at the https://www.facebook.com/PAGENAME?sk=app_APPID. What's cool about the javascript redirect is that the redirect is not ran by the linter, so it can pickup the correct og: tags, while also allowing you to have the user go directly to the page tab. Good luck!
Since the content of your Page Tab is located inside an iFrame the Facebook scraper will always see first the meta tags outside the iFrame which are set by Facebook and which describe your Facebook Page. Try the url in the Facebook tool and see at the bottom of the page what the scraper sees for your url. Unfortunately you can not change those Facebook meta tags from within your iFrame. That is why the only way to achieve what you want is to go by a redirect. I have done this before using the following code:
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en" xmlns:og="http://ogp.me/ns#">
<head>
<!-- Facebook meta tags -->
<meta property="og:title" content="bla"/>
<meta property="og:url" content="https://yourdomain.com/redirect.html"/>
<meta property="og:image" content="https://yourdomain.com/thumb.png"/>
<meta property="og:site_name" content="bla"/>
<meta property="fb:admins" content="1234"/>
<meta property="og:description" content="bla"/>
<meta property="og:type" content="website"/>
<meta property="og:video" content="https://yourdomain.com/bla.swf?param=bla"/>
<meta property="og:video:width" content="398"/>
<meta property="og:video:height" content="224"/>
<meta property="og:locale" content="de_DE"/>
<script type="text/javascript" src="swfobject.js"></script>
</head>
<body>
<!-- Check whether inside facebook -->
<script type="text/javascript">
function NotInFacebookFrame() {
return top === self;
}
function ReferrerIsFacebookApp() {
if(document.referrer) {
return document.referrer.indexOf("facebook.com") !== -1;
}
return false;
}
if (NotInFacebookFrame() || ReferrerIsFacebookApp()) {
top.location.replace("https://www.facebook.com/PAGENAME?sk=app_APPID");
}
</script>
<!-- content here -->
</body>
</html>
I'm a new user so I can't comment on DMCS's answer yet :-)
But I had to do this once, and it was also through a "redirector". However there was no need to set a timeout, simply:
<html>
<head>
<meta ...> <!-- OG tags -->
<script type="text/javascript">
location = 'http://www.facebook.com/PAGENAME?sk=app_APPID';
</script>
</head>
</html>
So no delay.
BTW. if you check the tab URL here, you'll see that it has a redirect path via its og:url tag that redirects from https://www.facebook.com/PAGENAME?sk=app_APPID to https://www.facebook.com/PAGENAME. Maybe you should check if setting the Default Landing Tab to your tab changes anything.
I too have been using the redirect method, but it is insufficient where users have an incentive to share content (for example in voting apps): all too often they copy the page tab URL from their browser and the shared content ends up having the generic page profile information associated with it.
But the good news is there is a solution! It's fairly complex though - especially if you have more than one subpage with different og:tags (such as in a voting competition for example).
How it works?
This solution is to set up ogtags on the page on your server to have a canonical url which redirects to the canvas app page - canvas apps are allowed to specify their own custom ogtags in this fashion. If you then redirect all users to the proper page tab, the canvas page will effectively not be viewable, yet it will allow you to provide custom ogtags for your page tab app.
The steps
Create a canvas page for your app (use the same urls as for the page tab)
Add og:tags to your page just as you would normally
Set the og:url parameter to the canvas app's url (http://apps.facebook.com/yourapp/...etc)
Add code so that when the request is coming from outside of the page tab iframe (in the canvas or directly on your server) you redirect the user to the proper page tab
I was having the same question... so here's what I did:
Redirection Page: A page that will get a parameter & set the tags for your sharing services or at least the OpenGraph tags. Then this page will craft a URL to a second page (Facebook Pagetab) like this:
//{facebook-page.link}/?sk=app_{your-app-id}&app_data=X
To obtain {facebook-page.link} see this example request:
See example: https://graph.facebook.com/200866110154
See documentation: https://developers.facebook.com/docs/reference/php/facebook-api/
Do not do the redirect immediately everytime, will not work. Instead do the redirect on certain conditions. Example:
if (strpos($_SERVER['HTTP_REFERER'], '//www.facebook.com/')) {
drupal_add_js('window.location = "' . $url_final . '"', 'inline');
}
Remember, to craft the URL use the page link attribute obtained from Facebook, not the ID of the page, otherwise you will lose the app_data parameter in the signed request.
Facebook Pagetab: A page called inside an Iframe of a tab of a Facebook page. This page will get the SignedRequest with the app_data and will load specific content that the end user will see.
Remember that app_data can also be an array (or a serialized object):
app_data[var1]=value1&app_data[var2]=value2
Tip: If you are using Drupal you can avoid the final redirect, just overwrite $_GET['q'] to the page need. This way you don't bootstrap Drupal only to do another redirect. You can achieve this using hook_init.
Tip: Save your requests to the Facebook API to speed up future calls. Every request to the graph API takes 300ms at least. Database access is obviously faster.
Related
When using Facebook Sharer, Facebook will offer the user the option of using 1 of a few images pulled from the source as a preview for their link. How are these images selected, and how can I ensure that any particular image on my page is always included in this list?
How do I tell Facebook which image to use when my page gets shared?
Facebook has a set of open-graph meta tags that it looks at to decide which image to show.
The keys one for the Facebook image are:
<meta property="og:image" content="http://ia.media-imdb.com/rock.jpg"/>
<meta property="og:image:secure_url" content="https://secure.example.com/ogp.jpg" />
and it should be present inside the <head></head> tag at the top of your page.
If these tags are not present, it will look for their older method of specifying an image: <link rel="image_src" href="/myimage.jpg"/>. If neither are present, Facebook will look at the content of your page and choose images from your page that meet its share image criteria: Image must be at least 200px by 200px, have a maximum aspect ratio of 3:1, and in PNG, JPEG or GIF format.
Can I specify multiple images to allow the user to select an image?
Yes, you just need to add multiple image meta tags in the order you want them to appear in. The user will then be presented with an image selector dialog:
I specified the appropriate image meta tags. Why isn't Facebook accepting the changes?
Once a url has been shared, Facebook's crawler, which has a user agent of facebookexternalhit/1.1 (+https://www.facebook.com/externalhit_uatext.php), will access your page and cache the meta information. To force Facebook servers to clear the cache, use the Facebook Url Debugger / Linter Tool that they launched in June 2010 to refresh the cache and troubleshoot any meta tag issues on your page.
Also, the images on the page must be publicly accessible to the Facebook crawler. You should specify absolute url's like http://example.com/yourimage.jpg instead of just /yourimage.jpg.
Can I update these meta tags with client side code like Javascript or jQuery?
No. Much like search engine crawlers, the Facebook scraper does not execute scripts so whatever meta tags are present when the page is downloaded are the meta tags that are used for image selection.
Adding these tags causes my page to no longer validate. How can I fix this?
You can add the necessary Facebook namespaces to your tag and your page should then pass validation:
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:og="http://ogp.me/ns#"
xmlns:fb="https://www.facebook.com/2008/fbml">
When you share for Facebook, you have to add in your html into the head section next meta tags:
<meta property="og:title" content="title" />
<meta property="og:description" content="description" />
<meta property="og:image" content="thumbnail_image" />
And that's it!
Add the button as you should according to what FB tells you.
All the info you need is in www.facebook.com/share/
As of 2013, if you're using facebook.com/sharer.php (PHP) you can simply make any button/link like:
<a class="btn" target="_blank" href="http://www.facebook.com/sharer.php?s=100&p[title]=<?php echo urlencode(YOUR_TITLE);?>&p[summary]=<?php echo urlencode(YOUR_PAGE_DESCRIPTION) ?>&p[url]=<?php echo urlencode(YOUR_PAGE_URL); ?>&p[images][0]=<?php echo urlencode(YOUR_LINK_THUMBNAIL); ?>">share on facebook</a>
Link query parameters:
p[title] = Define a page title
p[summary] = An URL description, most likely describing the contents of the page
p[url] = The absolute URL for the page you're sharing
p[images][0] = The URL of the thumbnail image to be used as post thumbnail on facebook
It's plain simple: you do not need any js or other settings. Is just an HTML raw link.
Style the A tag in any way you want to.
From my experience, the http://www.facebook.com/sharer.php does not use meta tags. It uses the string you pass. See below.
http://www.facebook.com/sharer.php?s=100&p[title]=THIS IS MY TITLE&p[summary]=THIS IS MY SUMMARY&p[url]=http://www.MYURL.com&&p[images][0]=http://www.MYURL.com/img/IMAGEADDRESS
The meta tags work with Facebook's developer like/send buttons, as does the other Open Graph info. So if you use one of Facebook's actual elements like the comments and such, that will all tie into the Open Graph stuff.
UPDATE: There are two ways to use the sharer * note the ?s versus the ?u value in the query string
1 ==> STRING: http://www.facebook.com/sharer.php?s + content from above
~~> Will pull info from the string.
2 ==> URL: http://www.facebook.com/sharer.php?u=url where url equals an actual url
~~> Will scrape the page provided in the url value
~~> You can test test the values here: https://developers.facebook.com/tools/debug
Put the following tag in the head:
<link rel="image_src" href="/path/to/your/image"/>
From http://www.facebook.com/share_partners.php
As far as what it chooses as the default in the absence of this tag, I'm not sure.
Old way, no longer works:
<link rel="image_src" href="http://yoururl/yourimage"/>
Reported new way, also does not work:
<meta property="og:image" content="http://yoururl/yourimage"/>
It randomly worked off and on during the first day I implemented it, hasn't worked at all since.
The Facebook linter page, a utility that inspects your page, reports that everything is correct and does display the thumbnail I selected... just that the share.php page itself doesn't seem to be functioning. Has to be a bug over at Facebook, one they apparently don't care to fix as every bug report regarding this issue I've seen in their system all say resolved or fixed.
To change Title, Description and Image, we need to add some meta tags under head tag.
STEP 1 :
Add meta tags under head tag
<html>
<head>
<meta property="og:url" content="http://www.test.com/" />
<meta property="og:image" content="http://www.test.com/img/fb-logo.png" />
<meta property="og:title" content="Prepaid Phone Cards, low rates for International calls with Lucky Prepay" />
<meta property="og:description" content="Cheap prepaid Phone Cards. Low rates for international calls anywhere in the world." />
NEXT STEP :
Click on below link
https://developers.facebook.com/tools/debug
Add your URL in text box (e.g http://www.test.com/) where you mentioned the tags.
Click on DEBUG button.
Its done.
You can verify here https://www.facebook.com/sharer/sharer.php?u=http://www.test.com/
In above url, u = your website link
ENJOY !!!!
For secure HTTPS
<meta property="og:image:secure_url" content="https://image.path.png" />
Use facebook feed dialog instead of share dialog to show custom Images
Example:
https://www.facebook.com/dialog/feed?app_id=1389892087910588
&redirect_uri=https://scotch.io
&link=https://scotch.io
&picture=http://placekitten.com/500/500
&caption=This%20is%20the%20caption
&description=This%20is%20the%20description
I had this problem and fixed it with manuel-84's suggestion. Using a 400x400px image worked great, while my smaller image never showed up in the sharer.
Note that Facebook recommends a minimum 200px square image as the og:image tag: https://developers.facebook.com/docs/opengraph/howtos/maximizing-distribution-media-content/#tags
This is what worked for me: I placed the desired thumbnail image on the page right after the tag and making it too small to see..
<img src="imagename.jpg" width="1" height="1" />
I have not tested it with height 0 and width 0 but it probably will still work.. This does not guarantee the user will select this image..
ALSO it seems like Facebook caches the thumbnails on your page and doesnt always check it for new ones.. try adding this to another page on your site and you'll see that it works.
I couldn't get Facebook to pick the right image from a specific post, so I did what's outlined on this page:
https://webapps.stackexchange.com/questions/18468/adding-meta-tags-to-individual-blogger-posts
In other words, something like this:
<b:if cond='data:blog.url == "http://urlofyourpost.com"'>
<meta content='http://urlofyourimage.png' property='og:image'/>
</b:if>
Basically, you're going to hard code an if statement into your site's HTML to get it to change the meta content for whatever you've changed for that one post. It's a messy solution, but it works.
When using Facebook Sharer, Facebook will offer the user the option of using 1 of a few images pulled from the source as a preview for their link. How are these images selected, and how can I ensure that any particular image on my page is always included in this list?
How do I tell Facebook which image to use when my page gets shared?
Facebook has a set of open-graph meta tags that it looks at to decide which image to show.
The keys one for the Facebook image are:
<meta property="og:image" content="http://ia.media-imdb.com/rock.jpg"/>
<meta property="og:image:secure_url" content="https://secure.example.com/ogp.jpg" />
and it should be present inside the <head></head> tag at the top of your page.
If these tags are not present, it will look for their older method of specifying an image: <link rel="image_src" href="/myimage.jpg"/>. If neither are present, Facebook will look at the content of your page and choose images from your page that meet its share image criteria: Image must be at least 200px by 200px, have a maximum aspect ratio of 3:1, and in PNG, JPEG or GIF format.
Can I specify multiple images to allow the user to select an image?
Yes, you just need to add multiple image meta tags in the order you want them to appear in. The user will then be presented with an image selector dialog:
I specified the appropriate image meta tags. Why isn't Facebook accepting the changes?
Once a url has been shared, Facebook's crawler, which has a user agent of facebookexternalhit/1.1 (+https://www.facebook.com/externalhit_uatext.php), will access your page and cache the meta information. To force Facebook servers to clear the cache, use the Facebook Url Debugger / Linter Tool that they launched in June 2010 to refresh the cache and troubleshoot any meta tag issues on your page.
Also, the images on the page must be publicly accessible to the Facebook crawler. You should specify absolute url's like http://example.com/yourimage.jpg instead of just /yourimage.jpg.
Can I update these meta tags with client side code like Javascript or jQuery?
No. Much like search engine crawlers, the Facebook scraper does not execute scripts so whatever meta tags are present when the page is downloaded are the meta tags that are used for image selection.
Adding these tags causes my page to no longer validate. How can I fix this?
You can add the necessary Facebook namespaces to your tag and your page should then pass validation:
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:og="http://ogp.me/ns#"
xmlns:fb="https://www.facebook.com/2008/fbml">
When you share for Facebook, you have to add in your html into the head section next meta tags:
<meta property="og:title" content="title" />
<meta property="og:description" content="description" />
<meta property="og:image" content="thumbnail_image" />
And that's it!
Add the button as you should according to what FB tells you.
All the info you need is in www.facebook.com/share/
As of 2013, if you're using facebook.com/sharer.php (PHP) you can simply make any button/link like:
<a class="btn" target="_blank" href="http://www.facebook.com/sharer.php?s=100&p[title]=<?php echo urlencode(YOUR_TITLE);?>&p[summary]=<?php echo urlencode(YOUR_PAGE_DESCRIPTION) ?>&p[url]=<?php echo urlencode(YOUR_PAGE_URL); ?>&p[images][0]=<?php echo urlencode(YOUR_LINK_THUMBNAIL); ?>">share on facebook</a>
Link query parameters:
p[title] = Define a page title
p[summary] = An URL description, most likely describing the contents of the page
p[url] = The absolute URL for the page you're sharing
p[images][0] = The URL of the thumbnail image to be used as post thumbnail on facebook
It's plain simple: you do not need any js or other settings. Is just an HTML raw link.
Style the A tag in any way you want to.
From my experience, the http://www.facebook.com/sharer.php does not use meta tags. It uses the string you pass. See below.
http://www.facebook.com/sharer.php?s=100&p[title]=THIS IS MY TITLE&p[summary]=THIS IS MY SUMMARY&p[url]=http://www.MYURL.com&&p[images][0]=http://www.MYURL.com/img/IMAGEADDRESS
The meta tags work with Facebook's developer like/send buttons, as does the other Open Graph info. So if you use one of Facebook's actual elements like the comments and such, that will all tie into the Open Graph stuff.
UPDATE: There are two ways to use the sharer * note the ?s versus the ?u value in the query string
1 ==> STRING: http://www.facebook.com/sharer.php?s + content from above
~~> Will pull info from the string.
2 ==> URL: http://www.facebook.com/sharer.php?u=url where url equals an actual url
~~> Will scrape the page provided in the url value
~~> You can test test the values here: https://developers.facebook.com/tools/debug
Put the following tag in the head:
<link rel="image_src" href="/path/to/your/image"/>
From http://www.facebook.com/share_partners.php
As far as what it chooses as the default in the absence of this tag, I'm not sure.
Old way, no longer works:
<link rel="image_src" href="http://yoururl/yourimage"/>
Reported new way, also does not work:
<meta property="og:image" content="http://yoururl/yourimage"/>
It randomly worked off and on during the first day I implemented it, hasn't worked at all since.
The Facebook linter page, a utility that inspects your page, reports that everything is correct and does display the thumbnail I selected... just that the share.php page itself doesn't seem to be functioning. Has to be a bug over at Facebook, one they apparently don't care to fix as every bug report regarding this issue I've seen in their system all say resolved or fixed.
To change Title, Description and Image, we need to add some meta tags under head tag.
STEP 1 :
Add meta tags under head tag
<html>
<head>
<meta property="og:url" content="http://www.test.com/" />
<meta property="og:image" content="http://www.test.com/img/fb-logo.png" />
<meta property="og:title" content="Prepaid Phone Cards, low rates for International calls with Lucky Prepay" />
<meta property="og:description" content="Cheap prepaid Phone Cards. Low rates for international calls anywhere in the world." />
NEXT STEP :
Click on below link
https://developers.facebook.com/tools/debug
Add your URL in text box (e.g http://www.test.com/) where you mentioned the tags.
Click on DEBUG button.
Its done.
You can verify here https://www.facebook.com/sharer/sharer.php?u=http://www.test.com/
In above url, u = your website link
ENJOY !!!!
For secure HTTPS
<meta property="og:image:secure_url" content="https://image.path.png" />
Use facebook feed dialog instead of share dialog to show custom Images
Example:
https://www.facebook.com/dialog/feed?app_id=1389892087910588
&redirect_uri=https://scotch.io
&link=https://scotch.io
&picture=http://placekitten.com/500/500
&caption=This%20is%20the%20caption
&description=This%20is%20the%20description
I had this problem and fixed it with manuel-84's suggestion. Using a 400x400px image worked great, while my smaller image never showed up in the sharer.
Note that Facebook recommends a minimum 200px square image as the og:image tag: https://developers.facebook.com/docs/opengraph/howtos/maximizing-distribution-media-content/#tags
This is what worked for me: I placed the desired thumbnail image on the page right after the tag and making it too small to see..
<img src="imagename.jpg" width="1" height="1" />
I have not tested it with height 0 and width 0 but it probably will still work.. This does not guarantee the user will select this image..
ALSO it seems like Facebook caches the thumbnails on your page and doesnt always check it for new ones.. try adding this to another page on your site and you'll see that it works.
I couldn't get Facebook to pick the right image from a specific post, so I did what's outlined on this page:
https://webapps.stackexchange.com/questions/18468/adding-meta-tags-to-individual-blogger-posts
In other words, something like this:
<b:if cond='data:blog.url == "http://urlofyourpost.com"'>
<meta content='http://urlofyourimage.png' property='og:image'/>
</b:if>
Basically, you're going to hard code an if statement into your site's HTML to get it to change the meta content for whatever you've changed for that one post. It's a messy solution, but it works.
I am creating a Facebook iFrame tab application that features weekly interviews and uses a CMS to manage the interview content. I would like to be able to post a link to my newsfeed that points to the application tab and will show a preview with metadata in the newsfeed. Currently, there is no metadata showing up and it is just a blank link. How can I get Facebook to show a preview of the link to the application tab, the same as it would show a preview of a link to any website when posting to my newsfeed?
I know this was asked a long time ago but I figured I'll share more details on how I went about solving this issue:
Facebook does not read metadata from iFrame or application tabs. In other words, when you share a link of a Facebook tab, Facebook will override the meta data values of the iFrame page with the Page’s default ones. In order to work around this limitation, you can set up a redirect page with custom open graph meta tags. Here is how:
Create a redirect page called redirect.php with meta data information:
<html>
<head>
<title>Name of App</title>
<meta property="og:title" content="" />
<meta property="og:description" content="" />
<meta property="og:image" content="" />
<meta property="og:url" content="" />
<!-- This is a page redirect -->
<meta HTTP-EQUIV="REFRESH" content="0; url=URL_OF_FACEBOOK_APP">
</head>
</html>
Use Facebook URL Linter to scrape page (https://developers.facebook.com/tools/debug)
Enter the address of your app’s root URL.
Use Google Shortner and enter the address of the redirect.php that you set up.
http://goo.gl/
Now you can share the new Google Shortner link
Facebook doesn't read metadata from your iframed tab, but you can set up a redirect page with custom Open Graph meta tags as described in the Facebook Developers Forum here: http://forum.developers.facebook.net/viewtopic.php?id=96146
UPDATE 2012.05.20: forum.developers.facebook.net has been replaced by facebook.stackoverflow.com. The link I provided no longer works, but there are some helpful related threads on the new forum:
http://facebook.stackoverflow.com/questions/8407013/open-graph-information-for-a-link-to-a-page-tab
http://facebook.stackoverflow.com/questions/7197919/how-can-i-301-redirect-a-page-in-the-open-graph-and-retain-facebook-like-informa
http://facebook.stackoverflow.com/questions/6053657/open-graph-pages-can-i-use-a-stub-forwarding-page
I have implemented Facebook Open Graph Protocol Full Integration following the http://developers.facebook.com/docs/opengraph/ and http://www.websitedesign411.com/blog/facebook-open-graph-protocol-full-integration-walkthrough.
The Like buttons work and show in the Facebook feeds except for one page www.giantmango.com/contest. I have tried several alternatives like manually entering the content for the meta tags and an else statement for pages, but I am unable to get Facebook to recognize this page. Any ideas?
<?php } elseif (is_page()) { ?>
<meta property="og:title" content="「I LIKE CREATORS」 アートチャリティー&コンテストへようこそ！" />
<meta property="og:type" content="article" />
<meta property="og:description" content="「I LIKE CREATORS」 アートチャリティー&コンテストへようこそ！ 売上の一部は児童養護施設に寄付いたします。2011年2月21日(月)から2月28日(月)好きな作品に投票をして、抽選で10名様にアメリカ生まれのナチュラルケアブランド「バーツビーズ」の福袋またはハンドサルヴが当たります。" />
As mentioned in the comments of this answer, it's a caching problem and quoting from Facebook (Editing Meta Tags):
For the changes to be reflected on
Facebook, you must force your page to
be scraped. The page is scraped when
an admin for the page clicks the Like
button or when the URL is entered into
the Facebook URL Linter.
So basically when I tested your page in the URL Linter, Facebook grabbed (scraped) the current data for the open graph meta tags.
When using Facebook Sharer, Facebook will offer the user the option of using 1 of a few images pulled from the source as a preview for their link. How are these images selected, and how can I ensure that any particular image on my page is always included in this list?
How do I tell Facebook which image to use when my page gets shared?
Facebook has a set of open-graph meta tags that it looks at to decide which image to show.
The keys one for the Facebook image are:
<meta property="og:image" content="http://ia.media-imdb.com/rock.jpg"/>
<meta property="og:image:secure_url" content="https://secure.example.com/ogp.jpg" />
and it should be present inside the <head></head> tag at the top of your page.
If these tags are not present, it will look for their older method of specifying an image: <link rel="image_src" href="/myimage.jpg"/>. If neither are present, Facebook will look at the content of your page and choose images from your page that meet its share image criteria: Image must be at least 200px by 200px, have a maximum aspect ratio of 3:1, and in PNG, JPEG or GIF format.
Can I specify multiple images to allow the user to select an image?
Yes, you just need to add multiple image meta tags in the order you want them to appear in. The user will then be presented with an image selector dialog:
I specified the appropriate image meta tags. Why isn't Facebook accepting the changes?
Once a url has been shared, Facebook's crawler, which has a user agent of facebookexternalhit/1.1 (+https://www.facebook.com/externalhit_uatext.php), will access your page and cache the meta information. To force Facebook servers to clear the cache, use the Facebook Url Debugger / Linter Tool that they launched in June 2010 to refresh the cache and troubleshoot any meta tag issues on your page.
Also, the images on the page must be publicly accessible to the Facebook crawler. You should specify absolute url's like http://example.com/yourimage.jpg instead of just /yourimage.jpg.
Can I update these meta tags with client side code like Javascript or jQuery?
No. Much like search engine crawlers, the Facebook scraper does not execute scripts so whatever meta tags are present when the page is downloaded are the meta tags that are used for image selection.
Adding these tags causes my page to no longer validate. How can I fix this?
You can add the necessary Facebook namespaces to your tag and your page should then pass validation:
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:og="http://ogp.me/ns#"
xmlns:fb="https://www.facebook.com/2008/fbml">
When you share for Facebook, you have to add in your html into the head section next meta tags:
<meta property="og:title" content="title" />
<meta property="og:description" content="description" />
<meta property="og:image" content="thumbnail_image" />
And that's it!
Add the button as you should according to what FB tells you.
All the info you need is in www.facebook.com/share/
As of 2013, if you're using facebook.com/sharer.php (PHP) you can simply make any button/link like:
<a class="btn" target="_blank" href="http://www.facebook.com/sharer.php?s=100&p[title]=<?php echo urlencode(YOUR_TITLE);?>&p[summary]=<?php echo urlencode(YOUR_PAGE_DESCRIPTION) ?>&p[url]=<?php echo urlencode(YOUR_PAGE_URL); ?>&p[images][0]=<?php echo urlencode(YOUR_LINK_THUMBNAIL); ?>">share on facebook</a>
Link query parameters:
p[title] = Define a page title
p[summary] = An URL description, most likely describing the contents of the page
p[url] = The absolute URL for the page you're sharing
p[images][0] = The URL of the thumbnail image to be used as post thumbnail on facebook
It's plain simple: you do not need any js or other settings. Is just an HTML raw link.
Style the A tag in any way you want to.
From my experience, the http://www.facebook.com/sharer.php does not use meta tags. It uses the string you pass. See below.
http://www.facebook.com/sharer.php?s=100&p[title]=THIS IS MY TITLE&p[summary]=THIS IS MY SUMMARY&p[url]=http://www.MYURL.com&&p[images][0]=http://www.MYURL.com/img/IMAGEADDRESS
The meta tags work with Facebook's developer like/send buttons, as does the other Open Graph info. So if you use one of Facebook's actual elements like the comments and such, that will all tie into the Open Graph stuff.
UPDATE: There are two ways to use the sharer * note the ?s versus the ?u value in the query string
1 ==> STRING: http://www.facebook.com/sharer.php?s + content from above
~~> Will pull info from the string.
2 ==> URL: http://www.facebook.com/sharer.php?u=url where url equals an actual url
~~> Will scrape the page provided in the url value
~~> You can test test the values here: https://developers.facebook.com/tools/debug
Put the following tag in the head:
<link rel="image_src" href="/path/to/your/image"/>
From http://www.facebook.com/share_partners.php
As far as what it chooses as the default in the absence of this tag, I'm not sure.
Old way, no longer works:
<link rel="image_src" href="http://yoururl/yourimage"/>
Reported new way, also does not work:
<meta property="og:image" content="http://yoururl/yourimage"/>
It randomly worked off and on during the first day I implemented it, hasn't worked at all since.
The Facebook linter page, a utility that inspects your page, reports that everything is correct and does display the thumbnail I selected... just that the share.php page itself doesn't seem to be functioning. Has to be a bug over at Facebook, one they apparently don't care to fix as every bug report regarding this issue I've seen in their system all say resolved or fixed.
To change Title, Description and Image, we need to add some meta tags under head tag.
STEP 1 :
Add meta tags under head tag
<html>
<head>
<meta property="og:url" content="http://www.test.com/" />
<meta property="og:image" content="http://www.test.com/img/fb-logo.png" />
<meta property="og:title" content="Prepaid Phone Cards, low rates for International calls with Lucky Prepay" />
<meta property="og:description" content="Cheap prepaid Phone Cards. Low rates for international calls anywhere in the world." />
NEXT STEP :
Click on below link
https://developers.facebook.com/tools/debug
Add your URL in text box (e.g http://www.test.com/) where you mentioned the tags.
Click on DEBUG button.
Its done.
You can verify here https://www.facebook.com/sharer/sharer.php?u=http://www.test.com/
In above url, u = your website link
ENJOY !!!!
For secure HTTPS
<meta property="og:image:secure_url" content="https://image.path.png" />
Use facebook feed dialog instead of share dialog to show custom Images
Example:
https://www.facebook.com/dialog/feed?app_id=1389892087910588
&redirect_uri=https://scotch.io
&link=https://scotch.io
&picture=http://placekitten.com/500/500
&caption=This%20is%20the%20caption
&description=This%20is%20the%20description
I had this problem and fixed it with manuel-84's suggestion. Using a 400x400px image worked great, while my smaller image never showed up in the sharer.
Note that Facebook recommends a minimum 200px square image as the og:image tag: https://developers.facebook.com/docs/opengraph/howtos/maximizing-distribution-media-content/#tags
This is what worked for me: I placed the desired thumbnail image on the page right after the tag and making it too small to see..
<img src="imagename.jpg" width="1" height="1" />
I have not tested it with height 0 and width 0 but it probably will still work.. This does not guarantee the user will select this image..
ALSO it seems like Facebook caches the thumbnails on your page and doesnt always check it for new ones.. try adding this to another page on your site and you'll see that it works.
I couldn't get Facebook to pick the right image from a specific post, so I did what's outlined on this page:
https://webapps.stackexchange.com/questions/18468/adding-meta-tags-to-individual-blogger-posts
In other words, something like this:
<b:if cond='data:blog.url == "http://urlofyourpost.com"'>
<meta content='http://urlofyourimage.png' property='og:image'/>
</b:if>
Basically, you're going to hard code an if statement into your site's HTML to get it to change the meta content for whatever you've changed for that one post. It's a messy solution, but it works.