Framework implementation of the Strategy Design pattern.

strategy.js

import fs from 'fs';

/*
  Maintains three different strategies to mix and
  match solutions for different and changing manufacturer 
  requirements
*/

// Abstract Parsing Strategy
class AbstractParse {
  parse() {
    throw new Error('Not Implemented');
  }
}

// Abstract Proccessing Strategy
class AbstractProcess {
  process() {
    throw new Error('Not Implemented');
  }
}

// Abstract Serializing Strategy
class AbstractSerialize {
  serialize() {
    throw new Error('Not Implemented');
  }
}

// Example Implemented Parser
class PDFTextParse extends AbstractParse {
  parse() {
    // PDF Logic
    console.log('Parsing PDF to Text');
  }
}

// Example implemented processor
class GMProcess extends AbstractProcess {
  process() {
    // Process Text - State could belong here until finished
    console.log('Processing GM text');
  }
}

// Example implemented serializer
class CSVSerial extends AbstractSerialize {
  serialize() {
    // Serialize text into CSV format
    console.log('Serializing data to CSV');
  }
}

// The entry class
class Scrape {
  constructor(Parse, Process, Serialize) {
    this.parser = new Parse();
    this.processor = new Process();
    this.serializor = new Serialize();
  }

  run(inputFile) {
    // Could pipe if methods returned a common instance
    let text = this.parser.parse(inputFile);
    let processed = this.processor.process(text);
    return this.serializor.serialize(processed);
  }
}

// Entry Code - Wrapped in a module, or CLI interface
let GMScrape = new Scrape(PDFTextParse, GMProcess, CSVSerial);
let file = fs.readFileSynv('./example.pdf');
GMScrape.run(file);