Hello!
This was a fun little coding exercise meant to practice setting up a CI and CD pipeline for a web service and front-end web app that implements an RPN calculator.
I decided to implemented it with NodeJS and the Express server to serve both the API and the static front-end files, and used React to implement a simple Single-Page-App for the front-end.
In terms of the build pipeline, I decided to refresh myself on travis-ci for the build and test-run, codeclimate for static analysis, and heroku still seems nice as a free path for proof-of-concept prototypes.
- commit changes to github
- triggers travis-ci build (tests under Node 6 and 8)
- success triggers codeclimate
- success triggers heroku deployment
- triggers travis-ci build (tests under Node 6 and 8)
I stopped short of UI testing, I tend to use a Chef-built X11 vfb / headless environment for browser testing, but it's a lot of overhead for this and doesn't fit the travis pipeline as-is. Unsure of possible open-source friendly test environments out there (but I didn't go looking, perhaps another day).
There is a single API point at /api/v1/reduce that accepts a POST request
containing a JSON encoded array that represents the stack of elements to
process with the RPN algorithm.
The only content-type accepted and responded with at this time is
application/json.
If the stack sent is invalid, an http status 400 will be returned, along with the original input data.
Sample requests and responses:
[]->[][1,2]->[1,2][1,2,"+"]->[3][1,2,3,"+","+"]->[6]
Make sure you have Node >= 6 installed and on your path.
Set up the project with:
npm install
Run the unit tests with:
npm test
Start the local server with:
npm start
Check the local API with:
curl -X POST -d '[1,2,"+"]' -H 'accept: application/json' \
-H 'content-type: application/json' http://localhost:3000/api/v1/reduce
When running the local API, you can visit the front end by visiting http://localhost:3000/
You can view this app in production at Heroku