Get record id in lightning component which was added to a record page

Question

Let us suppose that I go to a record. Then I am editing its page by adding a custom component on the page.

Now I would like to be able to get a record id in the custom component which was added to the page. How can I do that?

Answer 1

You implement the force:hasRecordId interface on your component:

<aura:component implements="flexipage:availableForRecordHome,force:hasRecordId">

From there, you can get the ID at any point:

doInit: function(component, event, helper) {
  var recordId = component.get("v.recordId");
  // ...

Do not put your own attribute called recordId in to your component; it is defined by the force:hasRecordId interface for you automatically. You can read more in this developer blog post and in the documentation.