What is the best way to have a config file that can accept variables?-CodePudding

Say I have a use case for my config file like this:

function generateText(thisIsAVariable) {
  return `This is a sentence with a variable somewhere in the string
${thisIsAVariable} then more string... or not`;
}

I want to be able to import a config file that would transform the above:

import { SENTENCE_CONFIG } = "..."
// SENTENCE_CONFIG.some_sentence {"This is a sentence with a variable somewhere in the string
//[slug] then more string... or not"}


function generateText(thisIsAVariable) {
  return SENTENCE_CONFIG.some_sentence;
  // but have thisIsAVariable plugged in the appropriate "slug" so to speak
}

I know I can make a function to do this, but I want know if there is another way.

CodePudding user response：

One way to do this is to use a library like mustache.js which is a logic-less template engine. It allows you to replace placeholders in a string with actual data.

// config.js

export const SENTENCE_CONFIG = {
   some_sentence: "This is a sentence with a variable somewhere in the string {{slug}} then more string... or not",
};

// index.js

import { SENTENCE_CONFIG } from "./config";
import Mustache from "mustache";

function generateText(thisIsAVariable) {
   const data = {slug: thisIsAVariable};
   return Mustache.render(SENTENCE_CONFIG.some_sentence, data);
}

Also, the thisIsAVariable would be better if it was an object with all the key:values you want to replace on the config file.

For more info see: https://github.com/janl/mustache.js/

CodePudding user response：

You can create a string and add template variables inside of the string. Intentionally NOT using template ticks.

Then have a function that creates an anonymous function that returns a template literal with the string that you pass to it. Then have run call on that function to process the object passed to it.

Then simply pass a string and object of your variables.

This answer is a combination of this answer (https://stackoverflow.com/a/71801207/3684265) and a comment.

let content = {
  "sentence" : "This is your sentence. ${this.thisIsAVariable} and more"
}

function vars(templateString, templateVars) {
    return new Function('return `'   templateString   '`').call(templateVars)
}

function generateText(thisIsAVariable) {
  return vars(content.sentence,{thisIsAVariable});
}

console.log(generateText("TESTT"))