#Graphql fragments how to#
#Graphql fragments code#
#Graphql fragments free#

We mentioned the default loaders, but the repo contains a few extra ones.įor simplicity, we're going to use only the one responsible for extracting GraphQL SDL from code files. The GraphQL Tools library has a few already written loaders that GraphQL Config uses. AEM Content Fragments work together with the AEM GraphQL API (a customized implementation, based on standard GraphQL), to deliver structured content for use in your applications.

#Graphql fragments how to#

In some cases, you may want to extend that behavior and teach GraphQL Config how to look for GraphQL SDL (modularized schema for example) across many JavaScript or TypeScript files. GraphQL is currently used in two (separate) scenarios in Adobe Experience Manager (AEM): AEM Commerce consumes data from a Commerce platform via GraphQL. Your example just makes this into an explicit construction where the parameter passing can be made explicit as well. The parameters are inferred through a standard type check inference algorithm. gqls) and the document returned by any functioning GraphQL endpoint (specified by URL). In my GraphQL system, I currently treat a fragment as a (lambda) function. GraphQL Config, by default, understands the Introspection result stored in JSON file, GraphQL files (.

In previous examples, we pointed GraphQL Config to the aphql file. It's also capable of loading operations and fragments. (For more info, read the API reference of GraphQLProjectConfig.) Using variables inside fragments It is possible for fragments to access variables declared in the query or mutation. In the query below, we fetch posts and decide whether to fetch the title for them or not based on the skipTitle GraphQL variable. The concept of fragments is frequently used to split complicated application data requirements into smaller chunks, especially when you need to combine lots of UI components with different fragments into one initial data fetch. They allow you to skip or include a field based on the value of the if argument that is passed to the directive. GraphQL Config can generate a schema not only as GraphQLSchema object but also as a DocumentNode. skip and include directives can be applied to query fields. We can generate TypeScript or Flow definitions from our GraphQL schema and use these definitions as the prop type definition for our UI component. This can be used to our advantage for static typing with Flow or TypeScript.

Then, you pass your newly configured cache to ApolloClient to complete the process.Async function main ( ) Fragments in these caching clients are basically perfect matches for the data needs of the UI components.

Use possibleTypes.json to configure your cache during construction.

Or use the plugin fragment-matcher for graphql-codegen and configure it for apollo client 3. Although this approach is a big step in the right direction and I think this can work very well if you don’t plan to ever use anything other. This makes it much easier to detect and remove obsolete fields. Read the documentation about how to extract possibleTypes automatically using an introspection query. As you can see in the quite complex example above, by using fragments we manage to define fields only in components where they are used.

Query your server / schema to obtain the necessary information about unions and interfaces and write it to a file.

We recommend setting up a build step that extracts the necessary information from the schema into a JSON file, where it can be imported from when constructing the cache. The section below explains how to pass the necessary schema knowledge to the Apollo Client cache so unions and interfaces can be accurately matched and results validated before writing them into the store. Provided you are familiar with GraphQL, you have probably already heard or maybe even played with fragments: Thanks to. To inform the cache store about these polymorphic relationships, you need to pass possibleTypes option to InMemor圜ache below. In the first chapter, you’ll learn about the core concepts of GraphQL. Brought to you by the GraphQL Community and.

#Graphql fragments free#

This works in most cases, but it also means that Apollo Client cannot check the server response for you, and it cannot tell you when you're manually writing invalid data into the store using update, updateQuery, writeQuery, etc. This monorepo contains three packages: graphql-fragment-import/cli - an executable to perform graphql module importing. The free and open-source tutorial to learn all around GraphQL to go from zero to production. By default, Apollo Client's cache will use a heuristic fragment matcher, which assumes that a fragment matched if the result included all the fields in its selection set, and didn't match when any field was missing. Both Jedi and Droid are possible concrete types of Character, but on the client there is no way to know that without having some information about the schema. In the query above, allPeople returns a result of type Character.