Continuing on the theory covered in this course, this part will talk about application programming interfaces (APIs) and web services. Application Programming Interfaces APIs define how programs can be used by other programs. An API defines how methods are called and what feedback you can expect. It basically is the combination of documentation and the program itself.
As said, JSON is the format we will use as serialization format for answers given by the Open PHACTS LDA. The API actually supports XML, RDF, HTML, and TSV too, but I think JSON is a good balance between expressiveness and compactness.
HTML (HyperText Markup Language), the language of the web, is no longer the only language of the web. But it still is the primary language in which source code of webpages is shared. Originally, HTML pages were always static: the only HTML source of a web page was that was downloaded from a website. Nowadays, much HTML the is visualized in your web browser, is generated on the fly with JavaScript.
Never underestimate the power of lack of coding standards in code obfuscation. Just try randomly to read code you wrote a year ago or four years ago. You’ll be surprised with what you find. Coding standards are like the grammar in writing: they ensure that our message gets understood.
No course, with some good theory. In this six-day course, I plan to cover this computing theory. It’s very practice oriented: That should give them enough head start to work on something like this. The material will be more extensive, but I’ll give myself a head start, with some initial content.
One key feature of programming languages is the following: first, there is linearity. This is an important point that is not always clear to students who just start to program. In fact, ask yourself what the algorithm is for counting the chairs in the room where you are now sitting. Could a computer do that in the same way? How should your algorithm change? A key point is, is that the program is run step by step, in a linear way.
Now that I have wrote out the goals, what they students will practically do, and how to get started with the Open PHACTS platform, I will list how we will assess the students: a presentation on the second day, outlining the project and work plan, working source code at the end of the cour se, a final presentation, showing the results and conclusions. Primarily, they will be judged on their acquired programming skills.
The purpose of a web service is that you give it a question or task, and that it returns an answer. For example, we can ask the Open PHACTS platform what compounds it knows with aspirin in the name. We pass the question (with the API key) and get a list of matching compounds. Now, this communication is complex: it happens at many levels, which are spelled out in the Internet Model.
Now that we have the communication working with the Open PHACTS LDA, it is time to make a nice GUI.
I have outlined the scope of the six-day course: the students will learn to program while hacking on the Open PHACTS’ Linked Data API (LDA). The first step is to get an account for the LDA. I have already done that to save time. But these are the steps to take. You go to https://dev.openphacts.org/signup: You then approve the account via your email account and you are set. The account is needed to get an API key.
Our department will soon start the course Programming in the Life Sciences for a group of some 10 students from the Maastricht Science Programme. This is the first time we give this course, and over the next weeks I will be blogging about this course. First, some information.