Create New Posts using AWS Amplify's DataStore
To be able to create a new post, we can use AWS Amplify's DataStore. We are going to create a button that will prompt the user to fill in two fields, a title and the content. Then using DataStore.save we can save that user's post then console.log it to see that it will automatically auto-populated the owner's fields on the model when the new post is created.
Instructor: [0:00] We have authorization rules depending on whether or not a user is the owner of a model instance. We'll check how Data Store auto-populates the owner field so that we could conditionally render forms based on whether a user is an owner or not.
[0:15] First, I'm going to import Data Store from AWS Amplify. The last time we used Data Store, we used it on the server, so we used the "with server-side rendering" context in order to access it. This time we'll be using it in the browser, so we'll import it directly from the Amplify libraries.
[0:32] We'll also need to import our post model. Let's create a button on our user interface that a user will click it in order to create a new post. We'll add an event listener to the button. We'll implement the createPost function.
[0:58] Instead of writing out a full form, I'll use window.prompt in order to ask the user for a title and content. Now I'll create a new post instance. I'll also save that new post to data store.
[1:37] Since our posts belong to blogs, on each provide a blog ID for my post. Normally, you'd implement a drop-down or something along those lines to choose between the blogs. For brevity's sake, I'll just use the first blog as my blog ID. I want to view all my posts.
[1:53] I'll add a few more lines of code in order to first query them and then console.log them. First, we'll create a new post. Let's test this out in the console. See that the post has the owner field which has the ID of the user that created the post.
[2:16] You could check to see if this owner ID matches the ID of the current signed-in user and only show a Delete or Create button if the user is the owner. We created a new post and saw how the owner field was auto-populated on the model.