In the previous post we set up our server using google-sign-in as identity server and we restricted access to the authenticated users. Today we’ll add real-time update thanks to GraphQL subscriptions.
The scenario we’ll implement is quite easy: we want to see in real-time when a new post is added to our list.
The first thing to do is to define the schema of our database creating the file posts.ts with author and comment:
After that we need to create the GraphQL schema post.schema.ts:
– a query to retrieve all the posts (line 11);
– a mutation to store a new post (line 14).
The resolver that implements all the functionalities post.resolver.ts:
The controller “post.controller.ts” that will interact with our mongoDb:
Our setup is completed and it’s time to add real-time data. Apollo Server 2.0 supports GraphQL subscriptions without additional configuration or packages.
In the post.schema.ts:
We added line 20-22 where we expect to receive all the new posts that are added and the related controller post.controller.ts that will interact with our mongoDB:
– line 19 to publish the new change;
– line 7-11 to add the subscription.
One small thing that makes me struggle quite a lot is the server.ts. In case you have defined a context remember to add:
As you can see Apollo Server 2.0 allows realtime data without invasive changes to existing code. For a full working example please have a look to this repo.
I’m proud to say that I wrote as well the documentation for subscriptions in the official doc of apollo and the repo I’ve create is linked there too!
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