graphql-compose/es/projection.js

GraphQL schema builder from different data sources with middleware extensions.

var _typeof = typeof Symbol === "function" && typeof Symbol.iterator === "symbol" ? function (obj) { return typeof obj; } : function (obj) { return obj && typeof Symbol === "function" && obj.constructor === Symbol && obj !== Symbol.prototype ? "symbol" : typeof obj; };

var _extends = Object.assign || function (target) { for (var i = 1; i < arguments.length; i++) { var source = arguments[i]; for (var key in source) { if (Object.prototype.hasOwnProperty.call(source, key)) { target[key] = source[key]; } } } return target; };

function _toConsumableArray(arr) { if (Array.isArray(arr)) { for (var i = 0, arr2 = Array(arr.length); i < arr.length; i++) { arr2[i] = arr[i]; } return arr2; } else { return Array.from(arr); } }

/* eslint-disable no-param-reassign, no-lonely-if */

import { FIELD, FRAGMENT_SPREAD, INLINE_FRAGMENT } from 'graphql/language/kinds';


export function getProjectionFromAST(context, fieldNode) {
  if (!context) {
    return {};
  }

  var selections = void 0;
  if (fieldNode) {
    if (fieldNode.selectionSet) {
      selections = fieldNode.selectionSet.selections;
    }
  } else if (Array.isArray(context.fieldNodes)) {
    // get all selectionSets
    selections = context.fieldNodes.reduce(function (result, source) {
      if (source.selectionSet) {
        result.push.apply(result, _toConsumableArray(source.selectionSet.selections));
      }
      return result;
    }, []);
  }

  var projection = (selections || []).reduce(function (list, ast) {
    switch (ast.kind) {
      case FIELD:
        list[ast.name.value] = getProjectionFromAST(context, ast) || true;
        return list;
      case INLINE_FRAGMENT:
        return _extends({}, list, getProjectionFromAST(context, ast));
      case FRAGMENT_SPREAD:
        return _extends({}, list, getProjectionFromAST(context, context.fragments[ast.name.value]));
      default:
        throw new Error('Unsuported query selection');
    }
  }, {});

  // this type params are setup via TypeComposer.addProjectionMapper()
  // Sometimes, when you create relations you need query additional fields, that not in query.
  // Eg. for obtaining `friendList` you also should add `friendIds` to projection.
  if (projection && context.returnType) {
    (function () {
      var returnType = context.returnType;
      while (returnType.ofType) {
        returnType = returnType.ofType;
      }

      // $FlowFixMe
      var mapper = returnType._gqcProjectionMapper;
      if (mapper && (typeof mapper === 'undefined' ? 'undefined' : _typeof(mapper)) === 'object') {
        Object.keys(mapper).forEach(function (key) {
          if (projection[key]) {
            Object.assign(projection, mapper[key]);
          }
        });
      }
    })();
  }
  return projection;
}

export function getFlatProjectionFromAST(context, fieldNodes) {
  var projection = getProjectionFromAST(context, fieldNodes) || {};
  var flatProjection = {};
  Object.keys(projection).forEach(function (key) {
    flatProjection[key] = !!projection[key];
  });
  return flatProjection;
}