I have a class where some properties shouldn't be stored to the indexedDB store. It works when I clone the object and remove the properties afterwards, however that solution I didn't like so much. I wondered if there is a solution where we just set a property somehow private, so when writing to the indexedDB store the property shouldn't be included.
I tried the following: I used a symbol in my class for a property and through get/set I modify the property, however when I try to store the object to the indexedDB store I get the following error: IndexedDB error: IDBObjectStore Symbol could not be cloned
Here is an example code:
var request = indexedDB.open('test', 2);
request.onerror = function(event) {
// Handle errors.
};
request.onupgradeneeded = function(event) {
var db = event.target.result;
// Create an objectStore to hold information about our customers. We're
// going to use "ssn" as our key path because it's guaranteed to be
// unique.
var objectStore = db.createObjectStore("customers", {
keyPath: 'id'
});
var mystring = "Hello World"
var myblob = new Blob([mystring], {
type: 'text/plain'
});
var file = new File([myblob], 'test');
var a = Symbol('a');
var obj = {
id: 'foo',
b: a
};
obj[a] = file;
objectStore.add(obj);
};
Objects that can be stored in IndexedDB must be serializable. The spec definition for this is:
https://html.spec.whatwg.org/multipage/structured-data.html#serializable-objects
Symbol values are explicitly called out in the algorithm steps as non-serializable.
You could exclude the property from serialization by making it non-enumerable, e.g.:
Object.defineProperty(obj, 'b', {value: a, enumerable: false});