@sterblue/sterblue-sdk/lib/utils/get-pagination-path.js

Sterblue Graph SDK for graphile.sterblue.com

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.getPaginationPath = void 0;

var _fp = require("lodash/fp");

var _graphqlTag = _interopRequireDefault(require("graphql-tag"));

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

// INFO: a selection is an entity in the query definition document

/**
 * Check if the current selection has `offset` and `first` as arguments and are declared as variables
 * @param selection {Object} a selection definition
 */
const haveFirstAndOffset = selection => {
  const args = (0, _fp.get)("arguments", selection);
  const indexOfFirst = (0, _fp.findIndex)({
    kind: "Argument",
    name: {
      kind: "Name",
      value: "first"
    },
    value: {
      kind: "Variable",
      name: {
        kind: "Name",
        value: "first"
      }
    }
  }, args);
  const indexOfOffset = (0, _fp.findIndex)({
    kind: "Argument",
    name: {
      kind: "Name",
      value: "offset"
    },
    value: {
      kind: "Variable",
      name: {
        kind: "Name",
        value: "offset"
      }
    }
  }, args);
  return indexOfFirst != -1 && indexOfOffset != -1;
};

const selectionsWithArguments = (0, _fp.filter)(selection => (0, _fp.size)(selection.arguments) != 0);
/**
 * "Recursive" Check if there is a first and a offset on the selection if yes the return the current path if not it trigger itself for all the subselection.
 * @param selection {Object} a selection definition
 * @param path {String} the path taken in the query definition to get to the current selection
 */

const getPaginationPathForOneSelection = (selection, path) => {
  const selectionName = (0, _fp.get)("name.value", selection);
  const currentPath = (0, _fp.isNil)(path) ? [selectionName] : [...path, selectionName];

  if (haveFirstAndOffset(selection)) {
    return currentPath;
  } else {
    const subSelectionWithArguments = selectionsWithArguments((0, _fp.get)("selectionSet.selections", selection));

    if ((0, _fp.size)(subSelectionWithArguments) == 0) {
      return null;
    } else {
      return getPaginationPathFromMultipleSelections(subSelectionWithArguments, currentPath);
    }
  }
};
/**
 * it's just Wrapper to trigger getPaginationPathForOneSelection on multiple selections
 * @param selections {Object[]} multiple selections definition
 * @param path {String} the path taken in the query definition to get to the current selection
 */


const getPaginationPathFromMultipleSelections = (selections, path) => {
  return (0, _fp.reduce)((localPath, subSelection) => {
    if ((0, _fp.isString)(localPath)) {
      return localPath;
    } else {
      return getPaginationPathForOneSelection(subSelection, path);
    }
  }, null, selections);
};
/**
 * exported function that get the path of the entity we want to paginate over
 * @param queryDefinition {Object || String} a query definition as a string or a document
 */


const getPaginationPath = queryDefinition => {
  const queryDocument = (0, _fp.isString)(queryDefinition) ? (0, _graphqlTag.default)(queryDefinition) : queryDefinition;
  const selections = (0, _fp.get)("definitions[0].selectionSet.selections", queryDocument);
  return getPaginationPathFromMultipleSelections(selections, null);
};

exports.getPaginationPath = getPaginationPath;