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Session: How to Get Entity ID

Entities does not have to contain an ID property or field. In the case of such an entity, and a need for knowing under what ID it is stored on the server, the getDocumentId() method was created.

Syntax

session.advanced.getDocumentId(instance);

Parameters
entity object Instance of an entity for which an ID will be returned
Return Value
string Returns the ID for a specified entity. The method may return null if entity is null, isn't tracked, or the ID will be generated on the server.

Example

class Comment {
    constructor (author, message) {
        this.author = author;
        this.message = message;
    }
}

const commentId = session.advanced.getDocumentId(comment);    // e.g. comments/1-A