Menarik langganan

Contoh kode ini dapat digunakan untuk menarik pesan yang dipublikasikan ke Topik Pub/Sub menggunakan langganan.

Untuk melihat kumpulan lengkap contoh kode ABAP SDK untuk Google Cloud, lihat repositori GoogleCloudPlatform/google-cloud-abap/abap-sdk /ZPrestaShop_SDK_DOCS_EXAMPLES di GitHub.

Contoh kode

**********************************************************************
*  Copyright 2023 Google LLC                                         *
*                                                                    *
*  Licensed under the Apache License, Version 2.0 (the "License");   *
*  you may not use this file except in compliance with the License.  *
*  You may obtain a copy of the License at                           *
*      https://www.apache.org/licenses/LICENSE-2.0                   *
*  Unless required by applicable law or agreed to in writing,        *
*  software distributed under the License is distributed on an       *
*  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,      *
*  either express or implied.                                        *
*  See the License for the specific language governing permissions   *
*  and limitations under the License.                                *
**********************************************************************

REPORT zr_pull_subscriptions.

DATA:
  lv_p_projects_id      TYPE string,
  lv_p_subscriptions_id TYPE string,
  ls_input              TYPE /goog/cl_pubsub_v1=>ty_026,
  ls_input_ack          TYPE /goog/cl_pubsub_v1=>ty_001.

TRY.

* Open HTTP Connection
    DATA(lo_client) = NEW /goog/cl_pubsub_v1( iv_key_name = 'CLIENT_KEY' ).

* Populate relevant parameters
    " Derive project id from the client object
    lv_p_projects_id = lo_client->gv_project_id.
    " Name of the subscription from where we want to pull data
    lv_p_subscriptions_id = 'SAMPLE_SUBSCRIPTION'.
    " Max number of messages that will be received in 1 API call
    ls_input-max_messages = 1.

* Call API method
    CALL METHOD lo_client->pull_subscriptions
      EXPORTING
        iv_p_projects_id      = lv_p_projects_id
        iv_p_subscriptions_id = lv_p_subscriptions_id
        is_input              = ls_input
      IMPORTING
        es_output             = DATA(ls_output)
        ev_ret_code           = DATA(lv_ret_code)
        ev_err_text           = DATA(lv_err_text)
        es_err_resp           = DATA(ls_err_resp).

    IF /goog/cl_http_client=>is_success( lv_ret_code ).
      IF ls_output-received_messages IS NOT INITIAL.
        "Messages published to Pub/Sub should be base-64 encoded, hence in order to get the exact message, we need to decode the data field.
        "However, attributes published to Pub/Sub should be accessible without any additional logic.
        DATA(lv_msg) = | Message Received: { cl_http_utility=>decode_base64( encoded = ls_output-received_messages[ 1 ]-message-data ) }|.
        APPEND ls_output-received_messages[ 1 ]-ack_id TO ls_input_ack-ack_ids.

* Call API method: pubsub.projects.subscriptions.acknowledge
        "Acknowledge the messages so it is not pulled again.
        CALL METHOD lo_client->acknowledge_subscriptions
          EXPORTING
            iv_p_projects_id      = lv_p_projects_id
            iv_p_subscriptions_id = lv_p_subscriptions_id
            is_input              = ls_input_ack
          IMPORTING
            es_output             = DATA(ls_output_ack)
            ev_ret_code           = lv_ret_code
            ev_err_text           = lv_err_text
            es_err_resp           = ls_err_resp.

        IF lo_client->is_success( lv_ret_code ).
          MESSAGE lv_msg TYPE 'S'.
        ELSE.
          MESSAGE lv_err_text TYPE 'E'.
        ENDIF.
      ELSE.
        MESSAGE 'No Messages were received!' TYPE 'S'.
      ENDIF.
    ELSE.
      MESSAGE lv_err_text TYPE 'E'.
    ENDIF.

* Close HTTP Connection
    lo_client->close( ).

  CATCH /goog/cx_sdk INTO DATA(lo_exception).
    MESSAGE lo_exception->get_text( ) TYPE 'E'.
ENDTRY.