graphql/utilities/buildClientSchema.mjs

import objectValues from '../polyfills/objectValues';
import inspect from '../jsutils/inspect';
import devAssert from '../jsutils/devAssert';
import keyValMap from '../jsutils/keyValMap';
import isObjectLike from '../jsutils/isObjectLike';
import { parseValue } from '../language/parser';
import { GraphQLDirective } from '../type/directives';
import { specifiedScalarTypes } from '../type/scalars';
import { introspectionTypes, TypeKind } from '../type/introspection';
import { GraphQLSchema } from '../type/schema';
import { isInputType, isOutputType, GraphQLScalarType, GraphQLObjectType, GraphQLInterfaceType, GraphQLUnionType, GraphQLEnumType, GraphQLInputObjectType, GraphQLList, GraphQLNonNull, assertNullableType, assertObjectType, assertInterfaceType } from '../type/definition';
import { valueFromAST } from './valueFromAST';

/**
 * Build a GraphQLSchema for use by client tools.
 *
 * Given the result of a client running the introspection query, creates and
 * returns a GraphQLSchema instance which can be then used with all graphql-js
 * tools, but cannot be used to execute a query, as introspection does not
 * represent the "resolver", "parse" or "serialize" functions or any other
 * server-internal mechanisms.
 *
 * This function expects a complete introspection result. Don't forget to check
 * the "errors" field of a server response before calling this function.
 */
export function buildClientSchema(introspection, options) {
  isObjectLike(introspection) && isObjectLike(introspection.__schema) || devAssert(0, 'Invalid or incomplete introspection result. Ensure that you are passing "data" property of introspection response and no "errors" was returned alongside: ' + inspect(introspection)); // Get the schema from the introspection result.

  var schemaIntrospection = introspection.__schema; // Iterate through all types, getting the type definition for each.

  var typeMap = keyValMap(schemaIntrospection.types, function (typeIntrospection) {
    return typeIntrospection.name;
  }, function (typeIntrospection) {
    return buildType(typeIntrospection);
  });

  for (var _i2 = 0, _ref2 = [].concat(specifiedScalarTypes, introspectionTypes); _i2 < _ref2.length; _i2++) {
    var stdType = _ref2[_i2];

    if (typeMap[stdType.name]) {
      typeMap[stdType.name] = stdType;
    }
  } // Get the root Query, Mutation, and Subscription types.


  var queryType = schemaIntrospection.queryType ? getObjectType(schemaIntrospection.queryType) : null;
  var mutationType = schemaIntrospection.mutationType ? getObjectType(schemaIntrospection.mutationType) : null;
  var subscriptionType = schemaIntrospection.subscriptionType ? getObjectType(schemaIntrospection.subscriptionType) : null; // Get the directives supported by Introspection, assuming empty-set if
  // directives were not queried for.

  var directives = schemaIntrospection.directives ? schemaIntrospection.directives.map(buildDirective) : []; // Then produce and return a Schema with these types.

  return new GraphQLSchema({
    query: queryType,
    mutation: mutationType,
    subscription: subscriptionType,
    types: objectValues(typeMap),
    directives: directives,
    assumeValid: options && options.assumeValid,
    allowedLegacyNames: options && options.allowedLegacyNames
  }); // Given a type reference in introspection, return the GraphQLType instance.
  // preferring cached instances before building new instances.

  function getType(typeRef) {
    if (typeRef.kind === TypeKind.LIST) {
      var itemRef = typeRef.ofType;

      if (!itemRef) {
        throw new Error('Decorated type deeper than introspection query.');
      }

      return GraphQLList(getType(itemRef));
    }

    if (typeRef.kind === TypeKind.NON_NULL) {
      var nullableRef = typeRef.ofType;

      if (!nullableRef) {
        throw new Error('Decorated type deeper than introspection query.');
      }

      var nullableType = getType(nullableRef);
      return GraphQLNonNull(assertNullableType(nullableType));
    }

    if (!typeRef.name) {
      throw new Error('Unknown type reference: ' + inspect(typeRef));
    }

    return getNamedType(typeRef.name);
  }

  function getNamedType(typeName) {
    var type = typeMap[typeName];

    if (!type) {
      throw new Error("Invalid or incomplete schema, unknown type: ".concat(typeName, ". Ensure that a full introspection query is used in order to build a client schema."));
    }

    return type;
  }

  function getInputType(typeRef) {
    var type = getType(typeRef);

    if (isInputType(type)) {
      return type;
    }

    throw new Error('Introspection must provide input type for arguments, but received: ' + inspect(type) + '.');
  }

  function getOutputType(typeRef) {
    var type = getType(typeRef);

    if (isOutputType(type)) {
      return type;
    }

    throw new Error('Introspection must provide output type for fields, but received: ' + inspect(type) + '.');
  }

  function getObjectType(typeRef) {
    var type = getType(typeRef);
    return assertObjectType(type);
  }

  function getInterfaceType(typeRef) {
    var type = getType(typeRef);
    return assertInterfaceType(type);
  } // Given a type's introspection result, construct the correct
  // GraphQLType instance.


  function buildType(type) {
    if (type && type.name && type.kind) {
      switch (type.kind) {
        case TypeKind.SCALAR:
          return buildScalarDef(type);

        case TypeKind.OBJECT:
          return buildObjectDef(type);

        case TypeKind.INTERFACE:
          return buildInterfaceDef(type);

        case TypeKind.UNION:
          return buildUnionDef(type);

        case TypeKind.ENUM:
          return buildEnumDef(type);

        case TypeKind.INPUT_OBJECT:
          return buildInputObjectDef(type);
      }
    }

    throw new Error('Invalid or incomplete introspection result. Ensure that a full introspection query is used in order to build a client schema:' + inspect(type));
  }

  function buildScalarDef(scalarIntrospection) {
    return new GraphQLScalarType({
      name: scalarIntrospection.name,
      description: scalarIntrospection.description
    });
  }

  function buildObjectDef(objectIntrospection) {
    if (!objectIntrospection.interfaces) {
      throw new Error('Introspection result missing interfaces: ' + inspect(objectIntrospection));
    }

    return new GraphQLObjectType({
      name: objectIntrospection.name,
      description: objectIntrospection.description,
      interfaces: function interfaces() {
        return objectIntrospection.interfaces.map(getInterfaceType);
      },
      fields: function fields() {
        return buildFieldDefMap(objectIntrospection);
      }
    });
  }

  function buildInterfaceDef(interfaceIntrospection) {
    return new GraphQLInterfaceType({
      name: interfaceIntrospection.name,
      description: interfaceIntrospection.description,
      fields: function fields() {
        return buildFieldDefMap(interfaceIntrospection);
      }
    });
  }

  function buildUnionDef(unionIntrospection) {
    if (!unionIntrospection.possibleTypes) {
      throw new Error('Introspection result missing possibleTypes: ' + inspect(unionIntrospection));
    }

    return new GraphQLUnionType({
      name: unionIntrospection.name,
      description: unionIntrospection.description,
      types: function types() {
        return unionIntrospection.possibleTypes.map(getObjectType);
      }
    });
  }

  function buildEnumDef(enumIntrospection) {
    if (!enumIntrospection.enumValues) {
      throw new Error('Introspection result missing enumValues: ' + inspect(enumIntrospection));
    }

    return new GraphQLEnumType({
      name: enumIntrospection.name,
      description: enumIntrospection.description,
      values: keyValMap(enumIntrospection.enumValues, function (valueIntrospection) {
        return valueIntrospection.name;
      }, function (valueIntrospection) {
        return {
          description: valueIntrospection.description,
          deprecationReason: valueIntrospection.deprecationReason
        };
      })
    });
  }

  function buildInputObjectDef(inputObjectIntrospection) {
    if (!inputObjectIntrospection.inputFields) {
      throw new Error('Introspection result missing inputFields: ' + inspect(inputObjectIntrospection));
    }

    return new GraphQLInputObjectType({
      name: inputObjectIntrospection.name,
      description: inputObjectIntrospection.description,
      fields: function fields() {
        return buildInputValueDefMap(inputObjectIntrospection.inputFields);
      }
    });
  }

  function buildFieldDefMap(typeIntrospection) {
    if (!typeIntrospection.fields) {
      throw new Error('Introspection result missing fields: ' + inspect(typeIntrospection));
    }

    return keyValMap(typeIntrospection.fields, function (fieldIntrospection) {
      return fieldIntrospection.name;
    }, function (fieldIntrospection) {
      if (!fieldIntrospection.args) {
        throw new Error('Introspection result missing field args: ' + inspect(fieldIntrospection));
      }

      return {
        description: fieldIntrospection.description,
        deprecationReason: fieldIntrospection.deprecationReason,
        type: getOutputType(fieldIntrospection.type),
        args: buildInputValueDefMap(fieldIntrospection.args)
      };
    });
  }

  function buildInputValueDefMap(inputValueIntrospections) {
    return keyValMap(inputValueIntrospections, function (inputValue) {
      return inputValue.name;
    }, buildInputValue);
  }

  function buildInputValue(inputValueIntrospection) {
    var type = getInputType(inputValueIntrospection.type);
    var defaultValue = inputValueIntrospection.defaultValue ? valueFromAST(parseValue(inputValueIntrospection.defaultValue), type) : undefined;
    return {
      description: inputValueIntrospection.description,
      type: type,
      defaultValue: defaultValue
    };
  }

  function buildDirective(directiveIntrospection) {
    if (!directiveIntrospection.args) {
      throw new Error('Introspection result missing directive args: ' + inspect(directiveIntrospection));
    }

    if (!directiveIntrospection.locations) {
      throw new Error('Introspection result missing directive locations: ' + inspect(directiveIntrospection));
    }

    return new GraphQLDirective({
      name: directiveIntrospection.name,
      description: directiveIntrospection.description,
      locations: directiveIntrospection.locations.slice(),
      args: buildInputValueDefMap(directiveIntrospection.args)
    });
  }
}