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Mohammad Waseem
Mohammad Waseem

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Mastering Data Hygiene: A Lead QA Engineer's Zero-Budget Approach with TypeScript

Mastering Data Hygiene: A Lead QA Engineer's Zero-Budget Approach with TypeScript

Ensuring the integrity of data is paramount for any successful software system. As a Lead QA Engineer operating with zero additional budget, the challenge lies not only in identifying dirty data but also in implementing cost-effective, scalable solutions. Leveraging TypeScript, a language renowned for its type safety and tooling, provides an efficient pathway to automate cleaning processes with minimal resources.

The Data Cleaning Dilemma

Dirty data can stem from multiple sources: inconsistent formats, null values, duplicate entries, or data entry errors. Manual cleaning is time-consuming and error-prone, especially when dealing with large datasets. Automated scripts are essential, but often they require expensive tools or infrastructure. Our goal is to develop a lightweight, maintainable solution using TypeScript — a language many teams already have in their stack.

Strategy Overview

The core strategy involves:

  • Validating data structures with TypeScript's type system.
  • Using native JavaScript/TypeScript features for cleaning logic.
  • Employing open-source libraries only if necessary, avoiding costly dependencies.
  • Ensuring code reusability and clarity.

Implementation: TypeScript Data Cleaning

Step 1: Define Data Types

Begin by explicitly defining data schemas. TypeScript's interfaces and types will serve as the blueprint.

interface RawData {
  id: string;
  name: string;
  email?: string;
  age: string | null;
}

interface CleanData {
  id: string;
  name: string;
  email: string | null;
  age: number | null;
}
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Step 2: Validate and Parse Raw Data

Create functions to validate data entries and convert types where needed.

function parseAge(ageStr: string | null): number | null {
  const ageNum = Number(ageStr);
  return isNaN(ageNum) ? null : ageNum;
}

function cleanRecord(record: RawData): CleanData {
  return {
    id: record.id.trim(),
    name: record.name.trim(),
    email: record.email ? record.email.trim() : null,
    age: parseAge(record.age),
  };
}
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Step 3: Remove Duplicates and Invalid Data

Implement a simple deduplication based on unique identifiers and filter out invalid entries.

function cleanData(records: RawData[]): CleanData[] {
  const seenIds = new Set<string>();
  const cleanedRecords: CleanData[] = [];

  for (const record of records) {
    if (seenIds.has(record.id.trim())) {
      continue; // skip duplicates
    }
    const cleaned = cleanRecord(record);
    // Filter out entries missing essential info
    if (cleaned.name && cleaned.id) {
      seenIds.add(cleaned.id);
      cleanedRecords.push(cleaned);
    }
  }
  return cleanedRecords;
}
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Step 4: Testing and Validation

Develop simple unit tests to verify data cleaning logic:

// Example raw data
const rawData: RawData[] = [
  { id: ' 1 ', name: ' Alice ', age: '30', email: ' alice@example.com ' },
  { id: '2', name: 'Bob', age: null },
  { id: '1', name: 'Alice', age: '30', email: ' alice@example.com ' }, // duplicate
  { id: '3', name: ' ', age: 'notANumber' }, // invalid
];

const cleaned = cleanData(rawData);
console.log(cleaned);

/* Output:
[
  { id: '1', name: 'Alice', email: 'alice@example.com', age: 30 },
  { id: '2', name: 'Bob', email: null, age: null }
]
*/
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Final Thoughts

Using TypeScript for data cleansing leverages existing skills and infrastructure while avoiding additional costs. It encourages writing clear, type-safe code that can be integrated into existing pipelines or scripts. With minimal dependencies and a focus on native capabilities, teams can build maintainable solutions that produce cleaner, more reliable data, ultimately improving the quality and trustworthiness of their systems.

This approach exemplifies how resourcefulness and sound engineering practices can compensate for budget constraints, delivering scalable data hygiene solutions in any environment.


🛠️ QA Tip

Pro Tip: Use TempoMail USA for generating disposable test accounts.

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