ABAP HTTP Client: REST-APIs aufrufen

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ABAP-Statements

Veröffentlicht

Nov 24, 2025

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HTTP-Clients ermöglichen die Kommunikation mit externen REST-APIs aus ABAP. Es gibt zwei Hauptklassen: CL_HTTP_CLIENT (klassisch) und CL_WEB_HTTP_CLIENT (modern/Cloud).

Übersicht

Klasse	Verfügbarkeit	Empfehlung
`CL_HTTP_CLIENT`	Klassisches ABAP	On-Premise
`CL_WEB_HTTP_CLIENT`	ABAP Cloud, ab 7.54	Cloud, neue Entwicklungen

CL_HTTP_CLIENT (Klassisch)

1. Einfacher GET-Request

DATA: lo_client   TYPE REF TO if_http_client,
      lv_response TYPE string,
      lv_code     TYPE i.

" Client erstellen
cl_http_client=>create_by_url(
  EXPORTING
    url    = 'https://api.example.com/users'
  IMPORTING
    client = lo_client
).

" Request senden
lo_client->send( ).
lo_client->receive( ).

" Response lesen
lv_code = lo_client->response->get_status( )-code.
lv_response = lo_client->response->get_cdata( ).

" Verbindung schließen
lo_client->close( ).

IF lv_code = 200.
  WRITE: / 'Erfolg:', lv_response.
ELSE.
  WRITE: / 'Fehler:', lv_code.
ENDIF.

2. GET mit Query-Parametern

DATA: lo_client TYPE REF TO if_http_client,
      lv_url    TYPE string.

" URL mit Parametern
lv_url = 'https://api.example.com/users?status=active&limit=10'.

cl_http_client=>create_by_url(
  EXPORTING url    = lv_url
  IMPORTING client = lo_client
).

" Oder Parameter einzeln setzen
lo_client->request->set_form_field(
  name  = 'status'
  value = 'active'
).

lo_client->send( ).
lo_client->receive( ).

DATA(lv_response) = lo_client->response->get_cdata( ).
lo_client->close( ).

3. POST-Request mit JSON

DATA: lo_client TYPE REF TO if_http_client,
      lv_json   TYPE string.

" JSON-Body erstellen
lv_json = '{"name":"Max","email":"max@example.com"}'.

cl_http_client=>create_by_url(
  EXPORTING url    = 'https://api.example.com/users'
  IMPORTING client = lo_client
).

" HTTP-Methode setzen
lo_client->request->set_method( if_http_request=>co_request_method_post ).

" Content-Type setzen
lo_client->request->set_header_field(
  name  = 'Content-Type'
  value = 'application/json'
).

" Body setzen
lo_client->request->set_cdata( lv_json ).

" Senden
lo_client->send( ).
lo_client->receive( ).

DATA(lv_status) = lo_client->response->get_status( )-code.
DATA(lv_response) = lo_client->response->get_cdata( ).

lo_client->close( ).

CASE lv_status.
  WHEN 200 OR 201.
    WRITE: / 'Erfolgreich erstellt'.
  WHEN 400.
    WRITE: / 'Ungültige Anfrage'.
  WHEN 401.
    WRITE: / 'Nicht autorisiert'.
  WHEN OTHERS.
    WRITE: / 'Fehler:', lv_status.
ENDCASE.

4. PUT-Request (Update)

lv_json = '{"name":"Max Mustermann","email":"max.m@example.com"}'.

cl_http_client=>create_by_url(
  EXPORTING url    = 'https://api.example.com/users/123'
  IMPORTING client = lo_client
).

lo_client->request->set_method( if_http_request=>co_request_method_put ).
lo_client->request->set_header_field(
  name  = 'Content-Type'
  value = 'application/json'
).
lo_client->request->set_cdata( lv_json ).

lo_client->send( ).
lo_client->receive( ).
lo_client->close( ).

5. DELETE-Request

cl_http_client=>create_by_url(
  EXPORTING url    = 'https://api.example.com/users/123'
  IMPORTING client = lo_client
).

lo_client->request->set_method( if_http_request=>co_request_method_delete ).

lo_client->send( ).
lo_client->receive( ).

DATA(lv_status) = lo_client->response->get_status( )-code.
lo_client->close( ).

IF lv_status = 204 OR lv_status = 200.
  WRITE: / 'Erfolgreich gelöscht'.
ENDIF.

6. Basic Authentication

cl_http_client=>create_by_url(
  EXPORTING url    = 'https://api.example.com/secure'
  IMPORTING client = lo_client
).

" Basic Auth setzen
lo_client->authenticate(
  username = 'myuser'
  password = 'mypassword'
).

lo_client->send( ).
lo_client->receive( ).
lo_client->close( ).

7. Bearer Token (OAuth)

DATA: lv_token TYPE string VALUE 'eyJhbGciOiJIUzI1NiIs...'.

cl_http_client=>create_by_url(
  EXPORTING url    = 'https://api.example.com/protected'
  IMPORTING client = lo_client
).

" Authorization Header setzen
lo_client->request->set_header_field(
  name  = 'Authorization'
  value = |Bearer { lv_token }|
).

lo_client->send( ).
lo_client->receive( ).
lo_client->close( ).

8. Custom Headers

lo_client->request->set_header_field(
  name  = 'X-API-Key'
  value = 'my-api-key-12345'
).

lo_client->request->set_header_field(
  name  = 'Accept'
  value = 'application/json'
).

lo_client->request->set_header_field(
  name  = 'Accept-Language'
  value = 'de-DE'
).

9. Timeout setzen

cl_http_client=>create_by_url(
  EXPORTING url    = 'https://api.example.com/slow'
  IMPORTING client = lo_client
).

" Timeout in Sekunden
lo_client->send( timeout = 30 ).
lo_client->receive( timeout = 30 ).

10. SSL/HTTPS-Zertifikate

" Für Self-Signed Zertifikate
lo_client->propertytype_accept_cookie = if_http_client=>co_enabled.

" SSL-Client-Zertifikat (STRUST)
lo_client->set_ssl_id( 'ANONYM' ).  " Oder PSE-Name

" SSL-Fehler ignorieren (NUR FÜR TESTS!)
lo_client->propertytype_logon_popup = if_http_client=>co_disabled.

CL_WEB_HTTP_CLIENT (Modern/Cloud)

11. GET-Request (Cloud)

DATA: lo_client   TYPE REF TO if_web_http_client,
      lo_response TYPE REF TO if_web_http_response.

TRY.
    " Destination aus SM59 oder HTTP-URL
    DATA(lo_destination) = cl_http_destination_provider=>create_by_url(
      i_url = 'https://api.example.com/users'
    ).

    lo_client = cl_web_http_client_manager=>create_by_http_destination(
      i_destination = lo_destination
    ).

    lo_response = lo_client->execute( if_web_http_client=>get ).

    DATA(lv_status) = lo_response->get_status( )-code.
    DATA(lv_body) = lo_response->get_text( ).

    lo_client->close( ).

  CATCH cx_web_http_client_error INTO DATA(lx_error).
    WRITE: / 'HTTP Error:', lx_error->get_text( ).
  CATCH cx_http_dest_provider_error INTO DATA(lx_dest).
    WRITE: / 'Destination Error:', lx_dest->get_text( ).
ENDTRY.

12. POST-Request (Cloud)

TRY.
    DATA(lo_destination) = cl_http_destination_provider=>create_by_url(
      i_url = 'https://api.example.com/users'
    ).

    DATA(lo_client) = cl_web_http_client_manager=>create_by_http_destination(
      i_destination = lo_destination
    ).

    DATA(lo_request) = lo_client->get_http_request( ).

    " Headers setzen
    lo_request->set_header_field(
      i_name  = 'Content-Type'
      i_value = 'application/json'
    ).

    " Body setzen
    lo_request->set_text( '{"name":"Max","email":"max@example.com"}' ).

    " POST ausführen
    DATA(lo_response) = lo_client->execute( if_web_http_client=>post ).

    DATA(lv_status) = lo_response->get_status( )-code.
    DATA(lv_body) = lo_response->get_text( ).

    lo_client->close( ).

  CATCH cx_web_http_client_error cx_http_dest_provider_error INTO DATA(lx_error).
    WRITE: / lx_error->get_text( ).
ENDTRY.

13. Mit Destination aus SM59

TRY.
    " Destination aus SM59 verwenden
    DATA(lo_destination) = cl_http_destination_provider=>create_by_comm_arrangement(
      comm_scenario  = 'Z_MY_SCENARIO'
      service_id     = 'Z_MY_SERVICE'
    ).

    " Oder direkt per Name
    DATA(lo_dest_by_name) = cl_http_destination_provider=>create_by_cloud_destination(
      i_name = 'MY_DESTINATION'
    ).

    DATA(lo_client) = cl_web_http_client_manager=>create_by_http_destination(
      i_destination = lo_destination
    ).

    " ...

  CATCH cx_http_dest_provider_error INTO DATA(lx_error).
    WRITE: / lx_error->get_text( ).
ENDTRY.

Praktische Beispiele

14. Kompletter REST-Client

CLASS zcl_api_client DEFINITION PUBLIC.
  PUBLIC SECTION.
    TYPES: BEGIN OF ty_user,
             id    TYPE i,
             name  TYPE string,
             email TYPE string,
           END OF ty_user,
           ty_users TYPE TABLE OF ty_user WITH EMPTY KEY.

    METHODS: constructor
               IMPORTING iv_base_url TYPE string
                         iv_api_key  TYPE string OPTIONAL.

    METHODS: get_users
               RETURNING VALUE(rt_users) TYPE ty_users
               RAISING   cx_web_http_client_error.

    METHODS: create_user
               IMPORTING is_user        TYPE ty_user
               RETURNING VALUE(rs_user) TYPE ty_user
               RAISING   cx_web_http_client_error.

  PRIVATE SECTION.
    DATA: mv_base_url TYPE string,
          mv_api_key  TYPE string.

    METHODS: create_client
               RETURNING VALUE(ro_client) TYPE REF TO if_http_client.
ENDCLASS.

CLASS zcl_api_client IMPLEMENTATION.
  METHOD constructor.
    mv_base_url = iv_base_url.
    mv_api_key = iv_api_key.
  ENDMETHOD.

  METHOD create_client.
    cl_http_client=>create_by_url(
      EXPORTING url    = mv_base_url
      IMPORTING client = ro_client
    ).

    IF mv_api_key IS NOT INITIAL.
      ro_client->request->set_header_field(
        name  = 'X-API-Key'
        value = mv_api_key
      ).
    ENDIF.

    ro_client->request->set_header_field(
      name  = 'Accept'
      value = 'application/json'
    ).
  ENDMETHOD.

  METHOD get_users.
    DATA(lo_client) = create_client( ).

    lo_client->request->set_uri_path( '/users' ).
    lo_client->send( ).
    lo_client->receive( ).

    DATA(lv_response) = lo_client->response->get_cdata( ).
    lo_client->close( ).

    " JSON parsen
    /ui2/cl_json=>deserialize(
      EXPORTING json = lv_response
      CHANGING  data = rt_users
    ).
  ENDMETHOD.

  METHOD create_user.
    DATA(lo_client) = create_client( ).

    lo_client->request->set_uri_path( '/users' ).
    lo_client->request->set_method( if_http_request=>co_request_method_post ).
    lo_client->request->set_header_field(
      name  = 'Content-Type'
      value = 'application/json'
    ).

    DATA(lv_json) = /ui2/cl_json=>serialize( data = is_user ).
    lo_client->request->set_cdata( lv_json ).

    lo_client->send( ).
    lo_client->receive( ).

    DATA(lv_response) = lo_client->response->get_cdata( ).
    lo_client->close( ).

    /ui2/cl_json=>deserialize(
      EXPORTING json = lv_response
      CHANGING  data = rs_user
    ).
  ENDMETHOD.
ENDCLASS.


" Verwendung
DATA(lo_api) = NEW zcl_api_client(
  iv_base_url = 'https://api.example.com'
  iv_api_key  = 'my-key'
).

TRY.
    DATA(lt_users) = lo_api->get_users( ).

    DATA(ls_new_user) = lo_api->create_user(
      is_user = VALUE #( name = 'Test' email = 'test@test.de' )
    ).

  CATCH cx_web_http_client_error INTO DATA(lx_error).
    WRITE: / lx_error->get_text( ).
ENDTRY.

15. Fehlerbehandlung

TRY.
    cl_http_client=>create_by_url(
      EXPORTING url    = 'https://api.example.com'
      IMPORTING client = lo_client
    ).

    lo_client->send( ).
    lo_client->receive( ).

    DATA(lv_status) = lo_client->response->get_status( ).

    CASE lv_status-code.
      WHEN 200.
        " Erfolg
        DATA(lv_data) = lo_client->response->get_cdata( ).

      WHEN 400.
        " Bad Request
        DATA(lv_error) = lo_client->response->get_cdata( ).
        WRITE: / 'Ungültige Anfrage:', lv_error.

      WHEN 401.
        WRITE: / 'Authentifizierung fehlgeschlagen'.

      WHEN 403.
        WRITE: / 'Zugriff verweigert'.

      WHEN 404.
        WRITE: / 'Ressource nicht gefunden'.

      WHEN 500.
        WRITE: / 'Server-Fehler'.

      WHEN OTHERS.
        WRITE: / 'HTTP-Status:', lv_status-code, lv_status-reason.
    ENDCASE.

  CATCH cx_root INTO DATA(lx_error).
    WRITE: / 'Fehler:', lx_error->get_text( ).

  CLEANUP.
    IF lo_client IS BOUND.
      lo_client->close( ).
    ENDIF.
ENDTRY.

16. Binärdaten (Dateien) senden

DATA: lv_file_content TYPE xstring.

" Datei als Binärdaten
lv_file_content = '...'.  " z.B. aus Datei oder Tabelle

lo_client->request->set_method( if_http_request=>co_request_method_post ).
lo_client->request->set_header_field(
  name  = 'Content-Type'
  value = 'application/octet-stream'
).

lo_client->request->set_data( lv_file_content ).

lo_client->send( ).
lo_client->receive( ).

17. Multipart/Form-Data

DATA: lv_boundary TYPE string VALUE '----WebKitFormBoundary7MA4YWxk'.

lo_client->request->set_header_field(
  name  = 'Content-Type'
  value = |multipart/form-data; boundary={ lv_boundary }|
).

DATA(lv_body) = |--{ lv_boundary }\r\n| &&
                |Content-Disposition: form-data; name="field1"\r\n\r\n| &&
                |value1\r\n| &&
                |--{ lv_boundary }\r\n| &&
                |Content-Disposition: form-data; name="file"; filename="test.txt"\r\n| &&
                |Content-Type: text/plain\r\n\r\n| &&
                |File content here\r\n| &&
                |--{ lv_boundary }--\r\n|.

lo_client->request->set_cdata( lv_body ).

Wichtige Hinweise / Best Practice

CL_WEB_HTTP_CLIENT für ABAP Cloud und neue Entwicklungen.
Immer close() aufrufen – auch bei Fehlern (TRY-FINALLY).
Destination (SM59) für konfigurierbare Endpoints verwenden.
Timeouts setzen für langsame externe APIs.
SSL-Zertifikate in STRUST importieren für HTTPS.
JSON mit /ui2/cl_json serialisieren/deserialisieren.
HTTP-Status-Codes auswerten für Fehlerbehandlung.
API-Keys/Tokens nicht im Code hardcoden – Destinations nutzen.
Logging für Debugging implementieren.
Beachten Sie Proxy-Einstellungen in Produktivsystemen.