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Homebrew TrackBack Tutorial

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Homebrew TrackBack Tutorial

Homebrew TrackBack Tutorial. Since I couldn’t find any documentation on how TrackBack works, I threw together this quick tutorial on the basic steps involved in sending and receiving TrackBack pings.

I’m also trying to come up with a way to use TrackBack with my project pages (and not just individual blog entries).

4 responses so far (Respond)


Matt, great write up. I had a few comments.

– I was wondering what the limits were for the excerpt. Is the URL limited to sending something like 255 characters of information? I’m trying to determine how much of an excerpt I can safely send out.

– How do you handle duplicate pings? Look up the same root URL for the same ID? Should duplicate pings replace originals (as someone might be fixing their tb system), or should they be ignored?

– I kind of like the way I handle people hitting the trackback url in their browser over an xml error message. If the tb script loads without additional URL data, I present a page explaining the system. Because it’s a link at the end of each new post at metafilter, I figured showing human friendly pages would be a better way to go than xml dumps.

mathowie | 27 Jul 2002

You raise some really good questions, Matt.

1. If over 256 characters, the excerpt is cut off at 253 characters (and appended with “…”). The title is automatically cut off at 5 words. However, both the title and blog_name seemed to be taking an almost unlimited number of characters when I was sending a single uninterrupted long word (I got bored after sending a 400 character word).

2. I haven’t yet come up with a system to handle duplicated pings, but I agree it’s potentially important. It appears that the MovableType code started to use IP addresses to track multiple pings, but the code is now commented out. One drawback to using root URLs to look for duplicates might be that someone who referenced the same URL from two different entries on their weblog might be blocked from having both of them show up (and should both pings be allowed to show up? I don’t know).

3. I think that the XML output is necessary in the MT implementation so that the blog sending the ping knows whether or not it was successful (MT seems to keep a record of pings that are SENT as well as received), and/or the reason for failure. But I agree with your friendly explanation page method.

It would nice to hear from Mena and Ben about what they consider to be the official TrackBack format so that other CMS’s can appropriately implement it.

I’m working on updating my tutorial with this information now.

Matt | 27 Jul 2002

Okay, it appears that the API for TrackBack will be released soon

Matt | 27 Jul 2002


Marazzi prin Omnitechgroup…

marazzi | 7 Sep 2006