bookstore

README

bookstore

The original challenge, in challenge.md, called it a "library management system", but variations of this are known as the "bookstore challenge".

This challenge is deployed live to https://bookstore.micahparks.com/. View the OpenAPI/swagger specification and docs here.

Features

• CRUD management of Book data.
• Web interface for Book data and Status data.
• Checking in and checking out books through the web interface.
• Historical Status data.
• OpenAPI/swagger 2.0 specification file for formatted docs, code generators, and good communication.
• Exporting all data as JSON or current statuses as CSV.
• Type safety around API on the backend. (Input and output validation.)
• Bulk API transactions. The spec is written with batch processing in mind.
• Switch between embedded frontend assets and live frontend assets by specifying a directory with the FRONTEND_DIR environment variable.
• Single, statically linked binary with all assets.
• A Docker image.
• Deployed live right now! https://bookstore.micahparks.com/
• A video walkthrough for the lazy (Firefox may not play sound for video URLs): https://bookstore.micahparks.com/demo.mp4

Design

The backend:

The backend is a Golang HTTP REST API. Its stub is generated from the swagger specification using goswagger.

Data storage is interacted with via a Go interface, to allow for multiple implementations.

All endpoints are placed under the /api/ prefix. Any other non-documentation paths will file serve from frontend assets.

The program is put into a Docker image with the base image scratch.

Deployed live, this sits on my personal VPS alongside other services using docker-compose behind a Caddy web server serving as a reverse proxy and TLS termination point.

The portable, statically linked executable.

The frontend:

The frontend is web app using "plain" HTML and JavaScript. Its assets are embedded directly in the executable for the server. There are a few external assets are served via CDNs.

The following technologies are used:

• HTML
• JavaScript
• Boostrap
• Font Awesome
• jQuery
• The Official Swagger JavaScript npm module via the unpkg.com CDN.

Project organization:

The cmd directory contains the entrypoint for the server. It was generated by goswagger.

The endpoints directory contains business logic behind the REST API endpoints. It consumes the data storage interfaces from the storage package.

The frontend directory contains all project specific frontend assets which include some JavaScript files and one HTML file. External frontend dependencies are brought in via CDNs.

The middleware directory contains HTTP middleware for the server. The only middleware present is the one used to serve the frontend assets via a directory from the OS or the embedded assets.

The models directory contains the data structures defined in the swagger specification file. It was generated by goswagger.

The producers directory contains implementations of the OpenAPI runtime.Producer interface. The only producer defined is a text producer used for the /api/csv endpoint.

The restapi directory contains most of the server stub generated by goswagger including input and output types, validation, and routing. There is a special file in restapi/configure_bookstore.go that was edited by hand to configure the service.

The storage directory contains the interface for backend storage and implementations for it.

The swagger.yml file is the swagger 2.0 specification file mentioned previously. It's contents can be viewed in a more pleasing graphical format at this link.

Screenshots

The main screen, a table:

Form submission for Book data:

Delete confirmation dialog:

Fixed bottom navbar with error present:

Improvements

• Write Go tests and Postman tests.
• Implement storage backend interfaces in persistent storage (non-memory).
• Introduce users, an identity provider, authentication, and authorization.
• ISBN validation on backend.
• Add an "On Hold" status and features around that.
• Form validation on frontend.
• Allow for bulk transactions through the web frontend (Already on the backend).
• Handle large strings on the frontend table.
• Add search functionality.
• Bulk, per ISBN, transactions for checkin and checkout.
• Better error messages to users.
• Don't reload the whole bookstore on the frontend during a refresh. (Backend is capable of this).
• Format times in a prettier way.
• Make the web interface prettier.
• Allow users to edit the number of books with the same ISBN.
• Use a frontend JavaScript framework (Vue).
• Make default backend timeout configurable.
• Support more than 18446744073709551615 books per ISBN.

Documentation

Index

• Constants
• Variables

Constants

const FrontendSubDir = "frontend"

FrontendSubDir is the name of the subdirectory to make the root of the embedded frontend.

Variables

var Frontend embed.FS

Frontend is the embedded file system for frontend assets.