message: Change string uri concat to string pattern and proof to const
diff: @@ -48,7 +48,7 @@ export class FacebookAPI {
  * @param payload An object to be sent as parameters to the API call.
  */
  public async callAPI(path: string, method: string = 'POST', payload: any = {}, query: any = {}): Promise<any> {
  - let proof = this.getAppSecretProof(this.token, this.secret);
  + const proof = this.getAppSecretProof(this.token, this.secret);
  let queryString = '?';
  @@ -61,7 +61,7 @@ export class FacebookAPI {
  method: method,
  json: true,
  body: payload,
  - uri: 'https://' + this.api_host + '/' + this.api_version + path + queryString + 'access_token=' + this.token + '&appsecret_proof=' + proof
  + uri: `https://${this.api_host}/${this.api_version}${path}${queryString}access_token=${this.token}&appsecret_proof=${proof}`
  }, (err, res, body) => {
  if (err) {
  reject(err);
  @@ -91,6 +91,7 @@ export class FacebookAPI {
  *
  * @param {string} path
  * @param {*} body
  + * @param {*} query
  * @returns {Promise<any>}
  * @memberof FacebookAPI
  */
  