Getting started
- Server Requirements
- What you will need to run GraphQL on a web server
- Configuring your schema
- Add a basic type to the schema configuration
- Building a schema with procedural code
- Use PHP code to build your schema
- Deploying the schema
- Deploy your GraphQL schema to a test or production environment
- Activating the default server
- Open up the default server that comes pre-configured with the module
- Building the schema
- Turn your schema configuration into executable code
Building the schema
The primary API surface of the silverstripe/graphql module is the YAML configuration, along
with some procedural configuration. It is important to understand
that none of this configuration gets interpreted at runtime. Loading the schema configuration
(which we refer to as the "schema definition") at runtime and converting it to executable code
has dire effects on performance, making API requests slower and slower as the schema grows larger.
To mitigate this problem, the schema that gets executed at runtime is generated PHP code. This code generation happens during a build step, and it is critical to run this build step whenever the schema definition changes, or a new schema definition is added.
What triggers a GraphQL code build?
- Any time you run the
sake graphql:buildcommand to explicitly build your GraphQL schemas. - Any time you run the
sake db:buildcommand on your project. silverstripe/graphqlwill attempt to generate your schema "on-demand" on the first GraphQL request only if it wasn’t already generated.
Relying on the "on-demand" schema generation on the first GraphQL request requires some additional consideration. See deploying the schema.
Running sake graphql:build
The main command for generating the schema code is sake graphql:build.
vendor/bin/sake graphql:build
This command takes an optional schema parameter. If you only want to generate a specific schema
(e.g. generate your custom schema, but not the CMS schema), you should pass in the name of the
schema you want to build.
If you do not provide a schema parameter, the command will build all schemas.
vendor/bin/sake graphql:build --schema=default
Most of the time, the name of your custom schema is default.
Keep in mind that some of your changes will be in YAML in the _config/ directory, which also
requires a flush.
vendor/bin/sake graphql:build --schema=default --flush
Building with sake db:build
By default, all schemas will be built during sake db:build. To disable this, change the config:
SilverStripe\GraphQL\Extensions\DevBuildExtension:
enabled: falseCaching
Generating code is a pretty expensive process. A large schema with 50 DataObject classes exposing
all their operations can take up to 20 seconds to generate. This may be acceptable
for initial builds and deployments, but during incremental development this can really
slow things down.
To mitigate this, the generated code for each type is cached against a signature. If the type hasn't changed, it doesn't get re-built. This reduces build times to under one second for incremental changes.
Clearing the schema cache
If you want to completely re-generate your schema from scratch, you can add --clear to the sake graphql:build command.
vendor/bin/sake graphql:build --schema=default --clear
If your schema is producing unexpected results, try using --clear to eliminate the possibility
of a caching issue. If the issue is resolved, record exactly what you changed and create an issue.
Build gotchas
Keep in mind that it's not always explicit schema definition changes that require a build. Anything influencing the output of the schema will require a build. This could include tangential changes such as:
- Updating the
$dbarray (or relationships) of aDataObjectclass that hasfields: '*'(i.e. include all fields on that class in the schema). - Adding a new resolver for a type that uses resolver discovery
- Adding an extension to a
DataObjectclass - Adding a new subclass of a
DataObjectclass that is already exposed
Viewing the generated code
By default, the generated PHP code is placed in the .graphql-generated/ directory in the root of your project.
It is not meant to be accessible through your webserver, Which is ensured by keeping it outside of the
public/ webroot and the inclusion of a .htaccess file in each schema folder.
Additional files are generated for CMS operation in public/_graphql/, and
those are meant to be accessible through your webserver.
See Tips and Tricks: Schema Introspection
to find out how to generate these files for your own schema.
While it is safe for you to view these files, you should not manually alter them. If you need to make a change to your GraphQL schema, you should update the schema definition and rebuild your schema.