mirror of
https://github.com/hasura/graphql-engine.git
synced 2024-12-13 19:33:55 +03:00
45 lines
2.1 KiB
Markdown
45 lines
2.1 KiB
Markdown
|
# Remote Schema Customization
|
||
|
|
|
||
|
|
## Motivation
|
||
|
|
|
||
|
|
- Prevent name conflicts between remote schemas and other sources
|
||
|
|
- Allow customization of third-party schemas to better fit with local naming conventions
|
||
|
|
|
||
|
|
## Spec
|
||
|
|
|
||
|
|
Add an optional `customization` object to the `add_remote_schema` API with the following form:
|
||
|
|
|
||
|
|
```yaml
|
||
|
|
customization:
|
||
|
|
# if root_fields_namespace is absent, the fields
|
||
|
|
# are merged into the query root directly
|
||
|
|
root_fields_namespace: "something"
|
||
|
|
type_names:
|
||
|
|
prefix: some_prefix
|
||
|
|
suffix: some_suffix
|
||
|
|
# mapping takes precedence over prefix and suffix
|
||
|
|
mapping:
|
||
|
|
old_name: new_name
|
||
|
|
field_names:
|
||
|
|
- parent_type: old_type_name
|
||
|
|
prefix: some_prefix
|
||
|
|
suffix: some_suffix
|
||
|
|
# mapping takes precedence over prefix and suffix
|
||
|
|
mapping:
|
||
|
|
old_name: new_name
|
||
|
|
```
|
||
|
|
|
||
|
|
- Type name prefix and suffix will be applied to all types in the schema except the root types (for query, mutation and subscription), types starting with `__`, standard scalar types (`Int`, `Float`, `String`, `Boolean`, and `ID`), and types with an explicit mapping.
|
||
|
|
- Root types, types starting with `__` and standard scalar types may only be customized with an explicit mapping.
|
||
|
|
- Fields that are part of an interface must be renamed consistently across all object types that implement that interface.
|
||
|
|
|
||
|
|
## Implementation approach
|
||
|
|
|
||
|
|
- After obtaining the remote schema via introspection we build customization functions (and their inverses) for the types and fields in the schema.
|
||
|
|
- Customizations are validated against the schema to ensure that:
|
||
|
|
- Field renamings of objects and interfaces are consistent
|
||
|
|
- Customization does not result in two types, or two fields of the same type, being renamed to the same name.
|
||
|
|
- The remote schema is customized using the customization functions to rename types and fields.
|
||
|
|
- The field parser generators are modified so that they recognise the customized schema, but generate GraphQL queries with the original names to be sent to the remote server
|
||
|
|
- We can uses aliases on the fields to make sure the response object has the customized fields names.
|