DEV Community: Subhankar De

Good to Great Designs - Q&A on Software Design

Subhankar De — Thu, 01 Apr 2021 01:21:43 +0000

Architecture?

Big Picture, What, Where of the software development process
Architecture Patterns(Microkernel, Microservices, Layered, Event-based, Space-based)
Trade-offs(Quality, Cost, Portability, Time to market, Longevity, Technical debt, etc.)
Technology, Storage, Security, Disaster Recovery

Design?

How of the software development process
Design Patterns
Classes, interfaces, functions

What is a good design?

Solves a problem
Easy to understand
Follows a common design pattern
Doesn't reinvent the wheel
Supported by everyone
Cost of changing the design is affordable

How to create high-quality designs?

Applying software design principles is the key to creating high-quality designs
Flow Charts & User stories with good acceptance criteria
Manage essential complexity
Eliminate accidental complexity
Document the rationales of the design decisions
Lots of small conversations with a lot of different people to get alignment

How to evaluate a design quality?

Adherence to Coarse-grained principles like abstraction, encapsulation, modularization, hierarchy, cohesion and coupling
Subjecting the design to change and then evaluate the cost
Adherence to Project-specific constraints such as language constraints, platform constraints, framework and library constraints, domain constraints, architectural constraints, hardware constraints, and process constraints

Who is a good designer?

Good designer is a great communicator
Approach
- What problem does this solve?
- Select a style that matches the needs of the problem
- How does this affect the user?
- Why this is better than the alternative?
- Designer shouldn't reinvent the wheel
Understanding
- See their perspective
- Remove distractions
- Anticipate reactions
- Clarify your assumption
Listening
- Let go off the ego
- Let them talk
- Hear what they're not saying
- Uncover the real problem
- Convert "Likes" into "Works"
- Ask for examples
Responding
- Give up control
- Lead with a Yes!

What are the tactics designer should use?

Appeal to a nobler motive during negotiations
Show a comparison
Propose an alternative
Give them a choice
Speak the language of your audience
Focus on acceptance criteria avoid gold plating
Postpone the decision, we are smarter tomorrow than today

Manage Your Brand Reputation - AWS Comprehend

Subhankar De — Tue, 23 Mar 2021 02:28:46 +0000

Motivation

In order to genuinely understand customers and increase retention, businesses need to focus a big part of their resources and manpower on customer feedback. The way someone approaches feedback can make or break their business.

The best way we can handle this is through digitization rather waiting for someone to reach the customer and get the feedback. After a customer leaves a feedback ‒ whether it’s to complain or appreciation on Twitter, email or voice there’s always an underlying emotion. With sentiment analysis, you can capture this subjective information to understand your customers better. Address the negative sentiment on priority and leverage the positive feedback for betterment of the business.

The below solution is a scaled down version of a sentiment analysis where a customer service associate exports customer feedback from Twitter, email or text from a voice call to a CSV file. As soon as this file is uploaded to a S3 bucket, sentiment analysis is done on each input and persisted into a DynamoDB table for further action.

Technology

AWS Lambda
AWS Step Function
AWS Comprehend
DynamoDB
Serverless Framework

Steps

The user uploads a CSV file with the feedback to S3
Currently supports English(EN) & Spanish(ES) in which the customer had given their feedback
S3 triggers a Lambda to read the file
Step Function does batch processing of the feedback by language using AWS Comprehend
This application inspects a batch of documents and returns an inference of the prevailing sentiment, POSITIVE, NEUTRAL, MIXED, or NEGATIVE, in each one
The processed files are copied to another S3 bucket
The number of documents in the request has a limit of 25
Each document must contain fewer that 5,000 bytes of UTF-8 encoded characters

Sample CSV file

datetime,account_number,language_code,text

2/12/01,333,en,you are awesome
2/13/01,375,es,Eres asombroso

Link to Github!

Future enhancement

Move the DynamoDB Put request from computeSentiment Lambda function to Step Functions
Generate customer sentiment from the call recording with the IVR
Use AWS Transcribe to convert it into text and then use the above flow

Serverless Framework Template

Subhankar De — Mon, 22 Mar 2021 17:27:22 +0000

Serverless Framework Template - ES6/ES7 Compatible

This Github project template will standardize

Consistent src folder structure across multiple projects.
serverless-bundle plugin: Optimally packages your ES6 or TypeScript Node.js Lambda functions with sensible defaults so you don't have to maintain your own Webpack configs.
serverless-pseudo-parameters plugin: Allows you to take advantage of CloudFormation Pseudo Parameters.

Getting started

sls create --name <YOUR_PROJECT_NAME> --template-url https://github.com/subhankarde/serverless-nodejs-es7-template.git
cd YOUR_PROJECT_NAME
npm install

The latest version of Webpack is not compatible. Please use the below version. Please be aware that AWS-SDK is in the DEV dependencies. Please move it to dependencies for PROD. AWS Lambda will use the latest SDK for the current template.

Latest npm packages

npm i -g npm-check-updates
ncu -u
npm install

Webpack version

npm uninstall webpack
npm install --save-dev webpack@4.46.0

VS Code command for Mac

code .

Top serverless plugins

serverless-offline
serverless-step-functions
serverless-plugin-canary-deployments
serverless-dynamodb-local