Currently, I am exploring the integration of GraphQL with Angular. So far, I have been able to scaffold the schema successfully using the @graphql-codegen package. The services generated are functional in querying the database.
However, I've noticed that the query results are structured unexpectedly, at least from my perspective. Although everything is strongly-typed, it seems like the intellisense is providing me with strongly-typed anonymous objects (similar to those in C#).
Let's take a look at this particular GraphQL Query:
query Animals {
animals {
id
name
latinName
created
changed
changedBy
}
}
When executed against the database, the result returned is in JSON format as follows:
{
"data": {
"animals": [
{
"id": 1,
"name": "Rehwild",
"latinName": "Capreolus capreolus",
"created": "2023-04-01T19:29:45.513Z",
"changed": "2023-04-01T19:29:45.513Z",
"changedBy": ""
},
{
"id": 2,
"name": "Dammwild",
"latinName": "Dama dama",
"created": "2023-04-01T19:29:45.513Z",
"changed": "2023-04-01T19:29:45.513Z",
"changedBy": ""
}
]
}
}
With the code generation process, my expectation was to receive an array of type Animal[] directly under the data property of the response, something akin to the following interface:
export interface Animal {
id: number;
name: string;
latinName: string;
created: string;
changed: string;
changedBy: string;
}
However, in the TypeScript code generated, there exists a type declaration for Animal which includes additional properties not explicitly requested in the above GraphQL query:
/** A specific animal that can be searched for and saved. */
export type Animal = {
__typename?: 'Animal';
changed: Scalars['DateTime'];
changedBy: Scalars['String'];
created: Scalars['DateTime'];
id: Scalars['Int'];
latinName?: Maybe<Scalars['String']>;
name: Scalars['String'];
timesDied: Array<Death>;
timesRescued: Array<Rescue>;
};
Consequently, when attempting to load the data in the constructor of my component:
constructor(private animals: AnimalsGQL) {
this.animals$ = this.animals.watch().valueChanges.pipe(map(result => result.data.animals));
}
I'm observing a return type different from what I expected, instead of receiving Animal[].
This discrepancy in type description poses challenges in various parts of my code. I would ideally prefer direct referencing to the relevant type rather than referring to an anonymous type. Does anyone know why this behavior is occurring? Details of my setup and the codegen configuration are provided below.
Any assistance on this matter would be highly appreciated.
package.json:
{
"name": "tests",
"version": "0.0.0",
"scripts": {
"ng": "ng",
"start": "ng serve",
"build": "ng build",
"watch": "ng build --watch --configuration development",
"test": "ng test",
"codegen": "cross-env NODE_TLS_REJECT_UNAUTHORIZED=0 graphql-codegen --config codegen.ts"
},
"private": true,
...
}
codegen.ts
import type { CodegenConfig } from '@graphql-codegen/cli';
const config: CodegenConfig = {
overwrite: true,
schema: "https://localhost:7029/graphql",
documents: "src/**/*.graphql",
generates: {
"src/graphql/generated/graphql.ts": {
plugins: ['typescript', 'typescript-operations', 'typescript-apollo-angular'],
config: {
addExplicitOverride: true
}
},
"./graphql.schema.json": {
plugins: ["introspection"]
}
}
};
export default config;