Developer FAQs

This FAQ is specifically for developers working with the Joost Widget API. It compliments the public Joost FAQ available from the support pages of the Joost site. If your question isn't answered here, it may be covered by the main FAQ.

For questions relating to the Joost client software, there is also a huge amount of documentation available on the Mozilla developer centre (for example on SVG). As this site grows, we intend to minimise the need for developers to search through other such sites by providing (here or through links) pointers to the most relevant and up-to-date documentation as it relates to Joost.

FAQs

Here are some questions that have been asked, by developers both within and outside Joost.

Getting started with Widget development

Q: How can I get started with Widget development?

A: You need to get set up with a working copy of Joost and an account with the service, then:

• Go to 'My Joost'
• Go to the Widget Manager

The Widget Manager Widget allows you to load packaged widgets from a file on your hard drive. Try the 'Do nothing' widget for a very basic example:

• Save the .joda file to your hard drive
• Use the widget manager to add a widget by browsing your hard drive using the 'add widget' button

The widget should display immediately.

Q: Can I use any Joost release?

A: We recommend you use the most recent release, which you can download here. You can use any version of Joost after the 0.11.0 release. You can also refer to our developer blog for the latest preview release which may give you a chance to try out new widget API features.

Q: Where can I find some examples to play with?

A: Examples are available here. These examples are licensed under the BSD-like JOWL license, so you can use the code in them (with attribution) in your own widgets.

Q: Where is the API documentation?

A: Here.

Q: Where are the tutorials?

A: Here.

Q: What do I do if I get stuck?

A: We have a Google Group list which you can join and some Joost developers hang out on IRC (Internet Relay Chat) at irc.freenode.net #joost-dev. We invite you to ask questions and make comments.

Technical Questions

Q: Is there a way of seeing where the errors are going?

A: Yes, pressing Ctrl-Shift-D (on both Mac and Windows) will bring up the error console. You can call the logMessage() function to write to it when needed.

Q: The console is too crowded, is there a way to log that could be dedicated to my widget?

A: Not provided directly, but it is very easy to emulate one. Simply take a look at the Basic Logger widget on the example page.

Q: My widget doesn't install/load, or I get nothing but the title

A: First double-check that all your XML is well-formed, that your <id> is correct, and to check the error log. If everything looks fine by those basic measures, contact the developer list for assistance, as your problem may have its source in more places than can be listed in a FAQ.

Q: What are the differences between Joost's XMLHttpRequest and the W3C's or Gecko's?

A: The differences are listed in detail in our documentation.

Q: What can I find out about what the viewer is watching? How much can I interact with the TV experience?

A: The full depth and breadth of how much of this a developer has access to is exposed in the Engine API documentation.

Q: Are there any tools to help me develop a widget?

A: Currently all you need to do is use a text editor to create the XML and JavaScript files you need, and a standard zip tool to make a .joda file. In the future we will introduce a requirement for widgets to be signed using certificates. As we move towards this phase we will provide tools to make this as simple and painless as possible.

Joost™ Open Widget License 1.0 (JOWL)

The FAQs below address questions that may arise in connection with your use or redistribution of widget software code licensed under the Joost™ Open Widget License 1.0 (the "JOWL 1.0"). This FAQ is intended to provide you with general information and do not constitute, and should not be viewed as constituting, legal advice. You should seek your own professional legal advice, including from legal counsel that has experience with proprietary and open source software licensing.

Q: I have used your widget sample code (under the JOWL 1.0) as the basis for my own code; which I want to keep proprietary. Is this allowed?

A: Yes, subject to (i) any exceptions listed in the JOWL 1.0, (ii) the notice and license requirements of the JOWL 1.0, and (iii) the Joost™ API Terms of Use, you may use the code as you see fit, and you may redistribute it with or without the source code under an open source license or under a proprietary license, whichever makes the most sense to you when developing your widget. You must follow the notice and license requirements set forth in the JOWL 1.0 with respect to any Joost code used or redistributed by you.

Q: My code is a mix of your sample widget code (under the JOWL 1.0) and some of my own proprietary code, and I want to keep the whole thing proprietary (including perhaps the changes and improvements I made to your code). Is this allowed?

A: Yes - subject to (i) any exceptions listed in the JOWL 1.0, (ii) the notice and license requirements of the JOWL 1.0, and (iii) the Joost™ API Terms of Use, you can license the code as you see fit, whether under an open source license, a proprietary license, or both. You must follow the notice and license requirements set forth in the JOWL 1.0 with respect to any Joost™ code used or redistributed by you.

Q: My code is a mix of your sample widget code (under the JOWL License 1.0) and some of my own proprietary code, and I want to distribute the whole thing under another open source license (e.g., the BSD license, the Mozilla License, the Apache License) including the changes and improvements I made to your code. Is this allowed?

A: Yes, subject to (i) any exceptions listed in the JOWL 1.0, (ii) the notice and license requirements of the JOWL 1.0, and (iii) the Joost™ API Terms of Use, you can license the code as you see fit, whether under an open source license, a proprietary license, or both. You must follow the notice and license requirements set forth in the JOWL 1.0 with respect to any Joost code used or redistributed by you.

Q: My code is a mix of your sample widget code (under the JOWL License 1.0) and some other open source code which has its own licensing conditions (e.g. it was under the Apache License). How do I distribute my code?

A: Read all the applicable licenses. It is important that you have a license to use the open source codes you are using. We recommend that you consult with legal counsel who understand open source licenses. You must follow the notice and license requirements set forth in the JOWL 1.0 with respect to any Joost code used or redistributed by you.