CS120 - Assignment 4

For this assignment, you will use jQuery to interact with my CS120 server’s “guest book” API. Your Webstorm project should be called assn4-mesg. You can access the simple user interface I demonstrated in class: http://cs120.liucs.net/assn4.

The available API includes these four services:

GET http://cs120.liucs.net/assn4/messages.json fetches all the messages in JSON format, in reverse chronological order. Each message is stored as an object like this:
```
{ "text":      "Hello class this is a test!"
, "sender":    "Chris",
, "timestamp": "2015-03-16T19:27:04.987Z"
, "mood":      "Tired"
}
```
POST http://cs120.liucs.net/assn4/messages.json saves a new message. You must send the data in JSON format, but without the “timestamp” (which is added automatically). The “mood” is optional. Here is a working example, using curl:
```
curl -H 'Content-Type: application/json' \
     -d '{"sender":"CL","text":"Hi!"}'   \
     http://cs120.liucs.net/assn4/messages.json
```
GET http://cs120.liucs.net/assn4/moods.json returns an alphabetical list of all the moods currently being used in messages on the server. The result, for example, could be:
```
["Curious","Hacking","Hungry","Jittery"]
```
GET http://cs120.liucs.net/assn4/complete/TEXT — replace “TEXT” with any word fragment, and this returns an alphabetical list of up to ten words that have the fragment as a prefix. For example:
```
curl http://cs120.liucs.net/assn4/complete/kar
["karachi","karamazov","karate","karen","karl","karma","karol","karp","karyatid"]
```

You should incorporate these services into a single page that uses jQuery to:

Refresh the displayed messages every 10 seconds, so new messages appear automatically.
Offer completions for moods currently being used (using <datalist>), but also allow free-form input of new moods.
Post a new message to the server, and then refresh the message list.

Demonstration video [9:32]

PDF version

Assignment 4 – jQuery