react-relay-network-modern/es/RelayRequest.js.flow

Network Layer for React Relay and Express (Batch Queries, AuthToken, Logging, Retry)

/* @flow */

import type { ConcreteBatch, Variables, CacheConfig, UploadableMap, FetchOpts } from './definition';
import RRNLError from './RRNLError';

function getFormDataInterface(): ?Class<FormData> {
  return (typeof window !== 'undefined' && window.FormData) || (global && global.FormData);
}

export default class RelayRequest {
  static lastGenId: number;
  id: string;
  fetchOpts: FetchOpts;

  operation: ConcreteBatch;
  variables: Variables;
  cacheConfig: CacheConfig;
  uploadables: ?UploadableMap;
  controller: ?window.AbortController;

  constructor(
    operation: ConcreteBatch,
    variables: Variables,
    cacheConfig: CacheConfig,
    uploadables?: ?UploadableMap
  ) {
    this.operation = operation;
    this.variables = variables;
    this.cacheConfig = cacheConfig;
    this.uploadables = uploadables;

    this.id = this.operation.id || this.operation.name || this._generateID();

    const fetchOpts: FetchOpts = {
      method: 'POST',
      headers: {},
      body: this.prepareBody(),
    };

    this.controller =
      typeof window !== 'undefined' && window.AbortController ? new window.AbortController() : null;
    if (this.controller) fetchOpts.signal = this.controller.signal;

    this.fetchOpts = fetchOpts;
  }

  getBody(): string | FormData {
    return this.fetchOpts.body;
  }

  prepareBody(): string | FormData {
    const { uploadables } = this;
    if (uploadables) {
      const _FormData_ = getFormDataInterface();
      if (!_FormData_) {
        throw new RRNLError('Uploading files without `FormData` interface does not supported.');
      }

      const formData = new _FormData_();
      formData.append('id', this.getID());
      formData.append('query', this.getQueryString());
      formData.append('variables', JSON.stringify(this.getVariables()));

      Object.keys(uploadables).forEach((key) => {
        if (Object.prototype.hasOwnProperty.call(uploadables, key)) {
          formData.append(key, uploadables[key]);
        }
      });

      return formData;
    }

    return JSON.stringify({
      id: this.getID(),
      query: this.getQueryString(),
      variables: this.getVariables(),
    });
  }

  getID(): string {
    return this.id;
  }

  _generateID(): string {
    if (!this.constructor.lastGenId) {
      this.constructor.lastGenId = 0;
    }
    this.constructor.lastGenId += 1;
    return this.constructor.lastGenId.toString();
  }

  getQueryString(): string {
    return this.operation.text || '';
  }

  getVariables(): Variables {
    return this.variables;
  }

  isMutation(): boolean {
    return this.operation.operationKind === 'mutation';
  }

  isFormData(): boolean {
    const _FormData_ = getFormDataInterface();
    return !!_FormData_ && this.fetchOpts.body instanceof _FormData_;
  }

  cancel(): boolean {
    if (this.controller) {
      this.controller.abort();
      return true;
    }
    return false;
  }

  clone(): RelayRequest {
    // $FlowFixMe
    const newRequest = Object.assign(Object.create(Object.getPrototypeOf(this)), this);
    newRequest.fetchOpts = { ...this.fetchOpts };
    newRequest.fetchOpts.headers = { ...this.fetchOpts.headers };
    return (newRequest: any);
  }
}