Storing Information

In Jinaga, information is stored in facts. Facts are immutable. That means that once you create one, you don't change it. Instead, you just create more facts.

Create a simple top-level fact.

[FactType("Blog.Site")]
public record Site(string domain);

var site = await jinagaClient.Fact(new Site("qedcode.com"));

Create a fact with a single predecessor. Why is this called a predecessor? Because it comes before. We have to have a site before we can write a blog post.

[FactType("Blog.Post")]
public record Post(DateTime createdAt, Site site);

var post = await jinagaClient.Fact(new Post(
  DateTime.UtcNow,  // Will be converted to an ISO string, such as "2018-12-23T22:46:02.487Z".
  site              // Site is the result of the previous jinagaClient.Fact.
));

You may be feeling that Jinaga facts are upside down. Typically, a JSON object contains its children. A site should contain its posts, not the other way around! But a Jinaga fact contains its parent. What's going on with that?

This all stems from the fact that Jinaga facts are immutable. You cannot change a fact. If a site contained an array of posts, then you would never be able to add another post. And so the relationship has to be flipped. A child knows its parent, because that parent relationship never changes.

To find all of the children of a fact, you need to write a query. By the way, we call these children successors, as you will soon see.