filesJSON

Open a json file, read the content into this and write the this's content back to the json file. Version that uses Promises!

npm i files-json

const { filesJSON, FileJSON } = require("files-json");

Class: FileJSON

fileJSON.write()

Returns <Promise>
resolve <Promise.resolve>
err <Null> | <Error>
Is an error in case fs.writeFile() had failed.
Returns a Promise that can be awaited and it resolves after the content from fileJSON has been passed through JSON.stringify() and the string has been written into the json file at the filepath. In case the json file does not exist the file will be created. Prototype method and prototype properties will never be pasred by JSON.stringify() and therefore are never written into the json file. This allows developers to create a self implemented class that can extend from the FilesJSON class and make new methods dedicated to a particular configuration file.

fileJSON.close()

new FileJSON(filepath)

filepath <string>
The filepath will be added to the filesJSON object.
Returns <Promise>
resolve <Promise.resolve>
fileJSON <object>
On reading either the content of a json file will be passed through JSON.parse() or a new empty fileJSON object is created and passed by the callback. In case the json file at the filepath was already opened, that fileJSON will be be passed over by the callback. In case the internal new FileJSON() was still reading and at the same time the same filepath is opened somewhere else by another new FileJSON() the latter will be put into a readQueue and return the same object as the first.
The callback will be executed when the internal fileJSON has finished creating the fileJSON.

filesJSON

Example

const test1 = async () => {
	const monkey1 = await new FileJSON("monkey.json");
	monkey1.says = "hoehoehaha";
	console.log("test1, monkey1:", monkey1);
	// "test1, monkey1: FileJSON { says: 'hoehoehaha' }" 
	await monkey1.write();
	// monkey.json did not exist yet and will be created
	const monkey2 = await new FileJSON("monkey.json");
	console.log("monkey1 === monkey2:", monkey1 === monkey2);
	monkey1.close();
	console.log(filesJSON);
	monkey2.close();
	console.log(filesJSON, "<-- empty, BUT WAIT monkey2-->", monkey2);
	// class FileJSON has removed all references to FileJSON("monkey.json")
	// However, monkey1 and monkey2 within this scope 
	// still reference to FileJSON("monkey.json")
};
const test2 = () => {
	new FileJSON("monkey.json").then(monkey3 => { // reads data from file
		console.log("test2, monkey3:", monkey3);
		// "test2, monkey3: FileJSON { says: 'hoehoehaha' }"
		monkey3.close();
	});
};
(async function test() {
	await test1();
	// all references to the FileJSON("monkey.json") are now gone, it is garbage collected
	test2();
})();