There's a new kind of "ping" implemented in this version of Radio3.

Instead of sending the address of the user's RSS feed to the receiver, we send the full contents of the post, encoded in JSON.

This makes a richer kind of connection possible, we expect.

Important caveat

Consider this an experimental feature. It's not frozen, it can change. Breakage could very easily happen. And it's conceivable the feature could be withdrawn.

Who this is for

Right now this is just for developers who can operate server applications.

When the messages are sent

When the user saves a new post, or edits an existing post, we send the update message.

How to set up

  1. Choose Settings in the system menu (at the right edge of the menu bar).

  2. Go to the Advanced panel.

  3. Enter the URL of your receiver app in the second spot.

Here's a screen shot.

I've put up a simple handler at the address in the screen shot. It echoes the JSON struct it receives. No guarantees this will remain up for any period of time.

If you want to watch it operate, open the debugging console in the browser. Radio3 shows you the struct it's sending before the send, and the struct it received back. At this time it does nothing with the returned value, but maybe we should use it.

Also: Getting started with Radio3.

Example

Here's an example of the JSON that's sent when a post is updated.

How to tell an update from a new post

A new post will have a ctSends value of 0. It's a serial number, so it increments with each post.

Other fields

You can use the twitterScreenName field to identify the user.

The when field is when the post was created.

text is the contents of the big edit box. It's used in the description element of the RSS item that represents the post.

idTweet is only present if the item has been posted to Twitter. You can turn off posting to Twitter through the Platforms panel in the Radio3 settings dialog, even though you must be signed in to Twitter to use Radio3. So you can't depend on idTweet being there.

guid is the value of the guid sub-element of item in the user's RSS feed.

I'm pretty sure the meaning of the other fields is self-evident. If there are questions, please post a comment below.

Identifying a post

The combination of twitterScreenName and when uniquely identifies a post.

09/13/14; 03:18:55 PM

Last built: Tue, Sep 16, 2014 at 10:48 AM

By Dave Winer, Saturday, September 13, 2014 at 3:18 PM.