Generic Workflow (WIP)

This is a living document for the workflow I have extrapolated from the courses I’ve done on NodeJS + Express. I will update this from time to time as I gain more experience in backend development.

1. Flowchart
2. Description of Steps
   1. Define the entities for the problem
   2. Define the required endpoints
   3. Design the data schema
   4. Choose an appropriate database
   5. Set up database
   6. Set up index.ts / app.ts
   7. Create placeholder controllers
   8. Create placeholder routes
   9. Set up and test routes in Postman
   10. Develop data models
   11. Plan for and create custom errors
   12. Incorporate logic in controllers
   13. Generate fake data
   14. Test app

Flowchart

flowchart TD;
  DefineEnts(Define the entities for the problem) --> DesignSchema(Design the data schema)

  %% Set up database
  DesignSchema --> ChooseDb(Choose an appropriate database)
  ChooseDb --> SetupDb("Set up database (barebones)")

  %% Set up app skeleton
  DefineEnts --> DefineEndpts("Define the required\nendpoints")
  DefineEndpts --> SetupEntrypt(Set up index.ts / app.ts)
  DefineEndpts --> CreateErrors(Plan for and create\ncustom errors)
  SetupEntrypt --> CreateCtl(Create placeholder controllers)
  CreateCtl --> CreateRtr(Create placeholder routers)
  CreateRtr --> SetupPostman("Set up and test routes\nin Postman")

  
  %% Set up model
  SetupPostman --> DevModels(Develop data models)
  SetupDb --> DevModels
  DevModels --> UpdateCtl("Incorporate logic\nin controllers")
  CreateErrors --> UpdateCtl

  %% Testing and improvement
  UpdateCtl --> GenData(Generate fake data)
  GenData --> Test(Test app)
  Test --> ImproveCtl(Fix/improve\ncontrollers)
  Test --> ImproveErrors(Fix/improve/add\nerrors)
  Test --> ImproveRoutes(Fix/add\nroutes)
  ImproveCtl --> Test
  ImproveErrors --> Test
  ImproveRoutes --> Test

Description of Steps

Define the entities for the problem

Do this based on your understanding of the business problem, process and the entities involved.

Define the required endpoints

If you’re building a REST API, it’s typically CRUD - Create, Read, Update, and Delete.

Design the data schema

• Identify the attributes on each entity
• Identify relationships among the entities
• Decide whether transactions are necessary - affects whether you go for SQL or NoSQL

Choose an appropriate database

Most likely PostgreSQL or MongoDB. But, there may be other database you require, like Redis as a cache, or blob storage for files.

Set up database

Get an instance running, set up credentials, and get the connection string.

Set up index.ts / app.ts

Set up the entrypoint with basic functionality, including placeholders for any functionality that is yet to be developed:

• Environment variables
• Middleware
  • JSON
  • Static
  • Security plugins
• Routes:
  • Home
  • Error handler
  • Not found
• Start server

Create placeholder controllers

Simple async functions that return a message saying what that controller does.

Create placeholder routes

Set up routes (as part of routers) for each entity, with the correct path and HTTP verb, and that call the correct controller.

Set up and test routes in Postman

Create new workspace and add all routes to it with sensible examples. If you need to use examples, don’t hard-code them into the URLs. Also, set up global variables where required.

Develop data models

If you chose PostgreSQL, it’s an object-relational mapping (ORM) like Sequelize. If you chose MongoDB, it’s an object-document mapper like Mongoose.

Plan for and create custom errors

You can anticipate what kinds of errors you will get. There’s the generic BadRequestError for any poorly-formed requests. If there’s authentication, there will surely be a need for an UnauthenticatedError.

Incorporate logic in controllers

Give your controllers some real functionality by putting some logic in: primarily interactions with the database and handling for any errors that you can foresee.

Generate fake data

You’ll need it for the next step.

Test app

I’m still learning how to do this.