Research Web-application¶
Requirements web-app¶
- Must have a page which can be used to control the Drawbot
- Can send commands to the jetbot
- Jetbot should be able to persist these commands
Possible Solutions¶
-
The Jetbot hosts a network. This network can be accessed by wifi. Go to a specific URL to control te Jetbot. Any commands can be sent to the Jetbot using a python queue.
-
The web-app has a back-end which handles the Jetbot commands coming from actions in the Front-end. Posts them to a database. Jetbot can fetch current commands waiting in queue. Jetbot fetches a single command per iteration and executes it.
-
Front-end sends commands to a queue waiting on the back-end side. Jetbot can
poll()this queue through an API. FIFO (queue). -
Front-end sends commands to the back-end which has socket functionality. The Drawbot hosts a queue which its content is managed by the socket.
Chosen solution¶
Solution 3: Front-end sends commands to a queue waiting on the back-end side. Jetbot can poll() this queue through an API. FIFO (queue).¶
We chose this solution because it requires the least resources, but meets all requirements.
How can we apply this solution?¶
Front-end¶
We require a single page which contains buttons to operate the Jetbot. Each time a button is pressed, the command is sent to the database which is hosted using X (Heroku?).
- Static HTML pages
- CSS for styling
- Using Javascript controller to send commands
Back-end and Drawbot¶
Consists of a model layer which is used to store all commands using a queue. An API is set up which is used to control this queue. For example: Front-end sends a POST request with a command to the API, which adds the cmomand to the queue. Drawbot sends a GET request to the API which sends the command back to the Drawbot. Drawbot can execute the command. Once finished, it fetches again.
- Class DrawbotQueue
- Model: ‘Command’, containing command information
- Model: ‘Drawbot’, containing a queue
of commands - Repository communicating with model queue
- Controller calls repository methods
API overview¶
| Method | Action | Endpoint | Body | Response |
|---|---|---|---|---|
| GET | Get all commands | /commands | 200 | |
| POST | Enqueue command | /insertCommand | { “command”: stop } | 201 |
| GET | Dequeue command | /getNextCommand | 200 |