Simple localStorage-based JS Data service

This small tool is intended to be used for simple frontend coding challenges/experiments. It requires no additional server/setup to access a REST-like data api.

The following documentation is based on the dataset that can be found here, but the tool intends to be a bit more flexible than that.

Initial data is read from a data/initialData.json file by default. This can be configured, but for convenience just place the above data set in a /data public folder.

Important note: This is a work in progress, some bugs may still arise. If so please report them and we'll try to solve them as soon as possible. Suggestions and PRs are welcome.

Installation

npm i simple-localstorage-data-service-stub

or in your package.json:

"simple-localstorage-data-service-stub": "^1.0.7"

Basic API

The service is intended to be used as a REST service. Thus the main public funtions have common rest verb names. All of them are asymetric and return a promise.

Initalization

import DataService from "simple-localstorage-data-service-stub";
const dataService = DataService();

Data access api

• get(resourceUrl)

dataService.get('products/6').then(product => console.log({product}));
dataService.get('suppliers').then(suppliers => console.log({suppliers}));
dataService.get('businessLogic').then(businessLogic => console.log({businessLogic}));

• create(resourceUrl, payload)

// Returns the newly created item.
dataService.create('salads', newSalad).then(salad => setCurrentSalad(salad));

• delete(resourceUrl)

// Returns the resulting collection after deletion.
dataService.delete('salads/4').then(salads => setSalads(salads));

• update(resourceUrl, payload)

// Returns the updated item.
dataService.update('salads/4', {name: "my new shiny salad"}).then(salad => setCurrentSalad(salad));

Additional storage aids

Since there's no real DB to store the data, we provide two simple file read/write functions to preserve changes beyond localStorage.

• saveData(fileName) => default filename is savedData.json, but since a file save dialog will be open this is almost irrelevant.
• uploadFileInput(event) => saves a local file based on the resulting event of a file upload:

const handleFileInput = (event) => {
  // It automatically updates the global data object with the parsed content, if successful.
  // Returns the parsed data (though no further action is needed).
  dataService.uploadFileInput(event).then(r => {
    // This response code is not required.
    event.target.value = null; // resets the input value.
    console.log("done!", {r})
  })
}

return <input type="file" id="input" onInput={handleFileInput}/>