Formatting JSON for browser.storage.local.set

Sam Hobbs

I want to use browser.storage.local.set in a Firefox sidebar extension. I am just new to JSON. I know many computer languages and formats but JSON is so much different from other things.

I just want to store a Model with an Id such as SKU1065 and a default Rating of 0 and empty Comments. So I think I want:

{SKU1065: {Rating:0, Comments:""}}

But the following is not working.

var Model = '{"' + CurrentId + ': {Rating:0, Comments:""}}';
browser.storage.local.set(Model);

When I run that code, browser.storage.local.set says it (Model) is not valid.

I hope this is very easy for many of you and if so I hope you don't mind providing an answer.

2 Replies

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Sreekanth Reddy7y ago
Accepted answer
Hi sam,
The problem is not at all with your data, I mean everything is good with your model.
What is the browser object.
Can you show how you created "browser" object ?
So that we can review it.
Thank you.
Sam Hobbs7y ago
Thank you, Sreekanth. The "browser" is an API; see storage.local - Mozilla | MDN. That documentation does not match exactly what I am using but it is close enough. And remember, this is for a Firefox extension: I don't know if the storage API works outside of extensions.

Actually the code I posted in my question produces:

"{\"SKU1065: {Rating:0, Comments:\"\"}}"

And I don't think that is right. So I did more research and developed the following. It will support updates of the data too.
class ModelClass {
constructor(Rating, Comments) {
this.Rating = Rating;
this.Comments = Comments;
}
}
var Model = new ModelClass(0, "");
var obj = {};
obj[Id] = Model;
That creates:
{"SKU1065":{"Rating":5,"Comments":"something"}}

See https://js.do/code/264565. And that works, the browser.storage.local.set(obj) works.

Update: evidently this site does not support links now (they did in the past). That storage.local article is at:
https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/storage/local