@theguild/federation-composition
Version:
Open Source Composition library for Apollo Federation
108 lines (107 loc) • 5.57 kB
JavaScript
import { GraphQLError, Kind } from 'graphql';
import { validateDirectiveAgainstOriginal } from '../../../helpers.js';
export function CostRule(context) {
return {
DirectiveDefinition(node) {
validateDirectiveAgainstOriginal(node, 'cost', context);
},
Directive(node, _key, _parent, paths, ancestors) {
if (!context.isAvailableFederationDirective('cost', node)) {
return;
}
const weightArg = node.arguments?.find(arg => arg.name.value === 'weight');
if (!weightArg) {
throw new Error('Expected @cost to have a "weight" argument');
}
if (weightArg.value.kind !== Kind.INT) {
throw new Error('Expected "@cost(weight:)" to be of type Int');
}
let weight;
try {
weight = parseInt(weightArg.value.value, 10);
}
catch (error) {
context.reportError(new GraphQLError(`Expected "@cost(weight:)" to be a valid integer, but got: ${weightArg.value.value}`, {
extensions: {
code: 'DIRECTIVE_COST_INVALID_WEIGHT',
},
}));
return;
}
context.stateBuilder.markCostSpecAsUsed('cost', node.name.value);
const directivesKeyAt = paths.findIndex(path => path === 'directives');
if (directivesKeyAt === -1) {
throw new Error('Could not find "directives" key in ancestors');
}
const parent = ancestors[directivesKeyAt];
if (!parent) {
throw new Error('Could not find the node annotated with @cost');
}
if (Array.isArray(parent)) {
throw new Error('Expected parent to be a single node');
}
if (!('kind' in parent)) {
throw new Error('Expected parent to be a node');
}
switch (parent.kind) {
case Kind.FIELD_DEFINITION: {
const typeDef = context.typeNodeInfo.getTypeDef();
if (!typeDef) {
throw new Error('Could not find the parent type of the field annotated with @cost');
}
if (typeDef.kind === Kind.OBJECT_TYPE_DEFINITION ||
typeDef.kind === Kind.OBJECT_TYPE_EXTENSION) {
context.stateBuilder.objectType.field.setCost(typeDef.name.value, parent.name.value, weight);
}
if (typeDef.kind === Kind.INTERFACE_TYPE_DEFINITION ||
typeDef.kind === Kind.INTERFACE_TYPE_EXTENSION) {
context.stateBuilder.interfaceType.field.setCost(typeDef.name.value, parent.name.value, weight);
}
break;
}
case Kind.INPUT_VALUE_DEFINITION:
const typeDef = context.typeNodeInfo.getTypeDef();
const fieldDef = context.typeNodeInfo.getFieldDef();
if (!typeDef) {
throw new Error('Could not find the parent type of the field annotated with @cost');
}
if (!fieldDef) {
throw new Error('Could not find the parent field of the argument annotated with @cost');
}
if (typeDef.kind === Kind.INPUT_OBJECT_TYPE_DEFINITION ||
typeDef.kind === Kind.INPUT_OBJECT_TYPE_EXTENSION) {
context.stateBuilder.inputObjectType.field.setCost(typeDef.name.value, fieldDef.name.value, weight);
}
if (typeDef.kind === Kind.OBJECT_TYPE_DEFINITION ||
typeDef.kind === Kind.OBJECT_TYPE_EXTENSION) {
const argDef = context.typeNodeInfo.getArgumentDef();
if (!argDef) {
throw new Error('Could not find the argument annotated with @cost');
}
context.stateBuilder.objectType.field.arg.setCost(typeDef.name.value, fieldDef.name.value, argDef.name.value, weight);
}
if (typeDef.kind === Kind.INTERFACE_TYPE_DEFINITION ||
typeDef.kind === Kind.INTERFACE_TYPE_EXTENSION) {
const argDef = context.typeNodeInfo.getArgumentDef();
if (!argDef) {
throw new Error('Could not find the argument annotated with @cost');
}
context.stateBuilder.interfaceType.field.arg.setCost(typeDef.name.value, fieldDef.name.value, argDef.name.value, weight);
}
break;
case Kind.OBJECT_TYPE_DEFINITION:
case Kind.OBJECT_TYPE_EXTENSION:
context.stateBuilder.objectType.setCost(parent.name.value, weight);
break;
case Kind.SCALAR_TYPE_DEFINITION:
case Kind.SCALAR_TYPE_EXTENSION:
context.stateBuilder.scalarType.setCost(parent.name.value, weight);
break;
case Kind.ENUM_TYPE_DEFINITION:
case Kind.ENUM_TYPE_EXTENSION:
context.stateBuilder.enumType.setCost(parent.name.value, weight);
break;
}
},
};
}