Introduction:

This blog post will describe in detail how to call an external API directly into ABAP system using API Key.(Background job to execute this code on daily basis. )

Requirement:

To verify if the data is coming as expected

Jason – Request

 Jason – Response:

Response

API Key – To fetch data from source system into ABAP

Step 2 – Certificate needs to be installed in “SSL Server Standard”

SSL Certificate

SSL Certificate

Step 2 – ABAP Program

REPORT  ztrigger_send_alert_msg.

* Include for Global Data Declaration.
INCLUDE ztrigger_send_alert_msg_a_top.
* Include for Selection Screen Definition.
INCLUDE ztrigger_send_alert_msg_a_sel.
* Include for Subroutines of the Program..
INCLUDE ztrigger_send_alert_msg_a_f00.

START-OF-SELECTION.
**************************************
*Prepare URL for API Access
**************************************
PERFORM get_url.

**************************************
*Read API Key from TVARVC
**************************************
PERFORM read_api_key.“Api key
**************************************
*prepare URL for connection
**************************************
READ TABLE gt_url INTO ls_url WITH KEY tdcompont =  c_thg_alert_mess_url.

CONCATENATE ls_url–zvr1 ls_url–zvr2 INTO lv_url.
**************************************
*Create HTTP Request
**************************************

CALL METHOD cl_http_client=>create_by_url
EXPORTING
url                = lv_url
IMPORTING
client             = http_client
EXCEPTIONS
argument_not_found = 1
plugin_not_active  = 2
internal_error     = 3
OTHERS             = 4.
*********************************
* set header fields
*********************************
PERFORM set_header_fields.

*  http_client->request->set_method( ‘GET’ ).
*********************************
* set json string for body
*********************************
PERFORM set_pack_body CHANGING ls_json.

lv_len = STRLEN( ls_json ).

**  *************xxx*************
**  **************************
**  **************************
*  DATA lv_payload_x TYPE xstring.
*  CALL FUNCTION ‘SCMS_STRING_TO_XSTRING’
*    EXPORTING
*      text   = ls_json
*    IMPORTING
*      buffer = lv_payload_x.
*
*  http_client->request->set_method( ‘POST’ ).
*  http_client->request->set_content_type( ‘application/json’ ).
*  http_client->request->set_data( lv_payload_x ).
*
**  **************************
**  **************************
**  **************xxx************

**********************************
* message body
**********************************
CALL METHOD http_client->request->set_cdata
EXPORTING
data   = ls_json
offset = 0
length = lv_len.
********************************
* Send request
********************************
CALL METHOD http_client->send
EXCEPTIONS
http_communication_failure = 1
http_invalid_state         = 2.

IF sy–subrc <> 0.
MESSAGE ‘Error while sending  HTTP request:’ TYPE  ‘E’.             ” connection error
ENDIF.
*
DATA: xstring_response TYPE xstring,
string_response  TYPE string.

*  CALL METHOD cl_http_utility=>escape_url
*    EXPORTING
*      unescaped = lv_url
*      OPTIONS   = 1
*    RECEIVING
*      escaped   = lv_url.

********************************
* Receive request
********************************

CALL METHOD http_client->receive
EXCEPTIONS
http_communication_failure = 1
http_invalid_state         = 2
http_processing_failed     = 3.

IF sy–subrc <> 0.

http_client->response->get_status(
IMPORTING
code   = lv_ret_code
reason = lv_err_string
).
MESSAGE lv_err_string TYPE ‘I’.
* Check for any response data
lv_response = http_client->response->get_cdata( ).

*   Write error to table
ls_zhd_error_log–vbeln      = p_aplid.
ls_zhd_error_log–type       = ‘E’.
ls_zhd_error_log–id         = c_id.
ls_zhd_error_log–zdate      = sy–datum.
ls_zhd_error_log–ztime      = sy–uzeit.
ls_zhd_error_log–message    = lv_response.
ls_zhd_error_log–message_v1 = lv_ret_code.
ls_zhd_error_log–message_v2 = lv_err_string.
ls_zhd_error_log–message_v3 = sy–host.

INSERT into zhd_error_log values ls_zhd_error_log.

*****************Insert Alert_Audit
****************Data Mapping: Insert ALERT_AUDIT
ls_zalert_audit–appl_id = p_aplid.
ls_zalert_audit–alert_id = p_alrtid.
ls_zalert_audit–user_id = p_userid.
ls_zalert_audit–key_data = p_keyd.

CONCATENATE sy–datum sy–uzeit INTO lv_timestamp.
lv_short_time_stamp = lv_timestamp.

ls_zalert_audit–posting_timestp = lv_short_time_stamp.“wa_zalert_subscripts-posting_timestp.
ls_zalert_audit–alert_action = c_action_f.
INSERT into zalert_audit values ls_zalert_audit.

MESSAGE ‘Error While receiving HTTP request:’ TYPE ‘E’.             ” connection error
ENDIF.

*  *****************************
*  *****************************
*  xstring_response = http_client->response->get_data( ).
*  string_response = cl_abap_codepage=>convert_from( xstring_response ).

*  *****************************
*  *****************************

http_client->response->get_status(
IMPORTING
code   = lv_http_code
reason = lv_code_reason
).
lv_code = lv_http_code.

CONCATENATE lv_code lv_code_reason INTO lv_reason SEPARATED BY space.

MESSAGE lv_reason TYPE ‘I’.

lv_response = http_client->response->get_cdata( ).
*  *   Write error to table
ls_zhd_error_log–vbeln      = p_aplid.
ls_zhd_error_log–type       = ‘S’.
ls_zhd_error_log–id         = c_id.
ls_zhd_error_log–zdate      = sy–datum.
ls_zhd_error_log–ztime      = sy–uzeit.
ls_zhd_error_log–message    = lv_response.
ls_zhd_error_log–message_v1 = lv_ret_code.
ls_zhd_error_log–message_v2 = lv_err_string.
ls_zhd_error_log–message_v3 = sy–host.

*****************Insert Alert_Audit
****************Data Mapping: Insert ALERT_AUDIT
ls_zalert_audit–appl_id = p_aplid.
ls_zalert_audit–alert_id = p_alrtid.
ls_zalert_audit–user_id = p_userid.
ls_zalert_audit–key_data = p_keyd.

CONCATENATE sy–datum sy–uzeit INTO lv_timestamp.
lv_short_time_stamp = lv_timestamp.

ls_zalert_audit–posting_timestp = lv_short_time_stamp.
ls_zalert_audit–alert_action = c_action_s.
INSERT into zalert_audit values ls_zalert_audit.

*&———————————————————————*
*&  Include           ZTRIGGER_SEND_ALERT_MSG_A_TOP
*&———————————————————————*
* Tables
DATA: gt_url TYPE TABLE OF zctrl_functions.

DATA: http_client TYPE REF TO if_http_client,
gs_api_key TYPE string,
lv_status_code TYPE i,
lv_status_text TYPE string,
lv_response TYPE string,
lv_url TYPE string,
ls_url LIKE zctrl_functions,
ls_api_key TYPE string,
ls_json     TYPE string,
lv_len      TYPE i,
gv_retry TYPE i,
gv_retry_success(1) TYPE c,
gv_wait TYPE i,
gv_logsave(1) TYPE c,
lv_err_string TYPE string,
lv_ret_code   TYPE sy–subrc,
lv_http_code TYPE sy–subrc,
lv_code TYPE string,
lv_code_reason TYPE string,
lv_reason TYPE string,
ls_zalert_audit TYPE zalert_audit,
ls_zhd_error_log TYPE zhd_error_log,
lv_timestamp TYPE char20,
lv_short_time_stamp TYPE timestamp.

CONSTANTS:   c_url(3) TYPE c VALUE ‘URL’,
c_thg_alert_mess_url(20)  TYPE c VALUE ‘THG_ALERT_MESS_URL’,
c_thg_alert_mess_url_key(25) TYPE c VALUE ‘THG_ALERT_MESS_URL_KEY’,
c_blank                         TYPE c VALUE ‘ ‘,
c_post                           TYPE string VALUE ‘POST’,
c_action_s                      TYPE string VALUE ‘SENT SUCCESS’,
c_action_f                      TYPE string VALUE ‘SENT FAILURE’,
c_id                            TYPE string VALUE ‘Trigger Send Alert Message’.

*&———————————————————————*
*&  Include           ZTRIGGER_SEND_ALERT_MSG_A_SEL
*&———————————————————————*

* Block 1: SELECTION CRITERIA
SELECTION-SCREEN BEGIN OF BLOCK b1 WITH FRAME TITLE text–001.

PARAMETERS : p_aplid  TYPE char40.
PARAMETERS : p_alrtid  TYPE char40.
PARAMETERS : p_userid  TYPE char80.
PARAMETERS : p_keyd  TYPE char80.
PARAMETERS : p_msgid  TYPE char80.
PARAMETERS : p_medtyp  TYPE char80.

SELECTION-SCREEN END OF BLOCK b1.

*&———————————————————————*
*&  Include           ZTRIGGER_SEND_ALERT_MSG_A_F00
*&———————————————————————*
*&———————————————————————*
*&      Form  GET_URL
*&———————————————————————*
*       text
*———————————————————————-*
*      <–P_GT_URL  text
*———————————————————————-*
FORM get_url.

CLEAR gt_url.

SELECT * FROM zctrl_functions  INTO TABLE  gt_url
WHERE  progname = sy–repid
AND  zpara    = c_url.

IF sy–subrc NE 0.
MESSAGE ‘Unable to get Sorted URLs for Connection.’ TYPE ‘E’. ” No Sorted URLs
ENDIF.
*

ENDFORM.                    ” GET_URL
*&———————————————————————*
*&      Form  READ_API_KEY
*&———————————————————————*
*       text
*———————————————————————-*
*      <–P_GS_API_KEY  text
*———————————————————————-*
FORM read_api_key.

SELECT SINGLE low FROM tvarvc INTO ls_api_key WHERE name = c_thg_alert_mess_url_key.

ENDFORM.                    ” READ_API_KEY
**&———————————————————————*
**&      Form  SET_HEADER_FIELDS
**&———————————————————————*
**       text
**———————————————————————-*
**      –>P_P_API_KEY  text
**      –>P_C_BLANK  text
**———————————————————————-*
FORM set_header_fields.

* Setup request header
CALL METHOD http_client->request->set_header_field
EXPORTING
name  = ‘Ocp-Apim-Subscription-Key’
value = ls_api_key.

* Setup request header
CALL METHOD http_client->request->set_header_field
EXPORTING
name  = ‘Accept’
value = ‘application/json’.
*
* Setup request header
CALL METHOD http_client->request->set_header_field
EXPORTING
name  = ‘Content-Type’
*      value = ‘application/json’.
value = ‘application/json ;charset=UTF-8’.

* Setup request header
CALL METHOD http_client->request->set_header_field
EXPORTING
name  = ‘~request_method’
value = c_post.

ENDFORM.                    ” SET_HEADER_FIELDS
**&———————————————————————*
**&      Form  SET_PACK_BODY
**&———————————————————————*
**       text
**———————————————————————-*
**  –>  p1        text
**  <–  p2        text
**———————————————————————-*
FORM set_pack_body CHANGING p_json.

p_json = ‘{‘.
CONCATENATE: p_json ‘”request”: {‘ INTO p_json.

CALL FUNCTION ‘CONVERSION_EXIT_MATN1_OUTPUT’
EXPORTING
input  = p_keyd
IMPORTING
output = p_keyd.

* exmp: CONCATENATE: p_json ‘”Width”:’ ls_width ‘,’ INTO p_json SEPARATED BY space.

CONCATENATE: p_json ‘”productId”:’ p_keyd ‘,’ INTO p_json.
CONCATENATE: p_json ‘”alertId”: “‘p_alrtid‘” ,’ INTO p_json SEPARATED BY space.
CONCATENATE: p_json ‘”recipients”: [‘ INTO p_json SEPARATED BY space.
CONCATENATE: p_json ‘{‘ INTO p_json SEPARATED BY space.

TRANSLATE p_userid TO LOWER CASE.
CONCATENATE: p_json ‘”emailAddress”: “‘p_userid‘”‘ INTO p_json SEPARATED BY space.
CONCATENATE: p_json ‘}’ INTO p_json SEPARATED BY space.
CONCATENATE: p_json ‘]’ INTO p_json SEPARATED BY space.
CONCATENATE: p_json ‘}’ INTO p_json SEPARATED BY space.
CONCATENATE: p_json ‘}’ INTO p_json SEPARATED BY space.
CONDENSE p_json NO–GAPS.

ENDFORM.                    ” SET_PACK_BODY
**&———————————————————————*
**&      Form  HTTP_RECEIVE_RETRY
**&———————————————————————*
**       text
**———————————————————————-*
**  –>  p1        text
**  <–  p2        text
**———————————————————————-*
FORM http_receive_retry .
CLEAR gv_retry_success.

* Retry HTTP receive for the configured number of times
DO gv_retry TIMES.

*   Check for wait
IF NOT gv_wait = space.
WAIT UP TO gv_wait SECONDS.
ENDIF.

*   HTTP receive
CALL METHOD http_client->receive
EXCEPTIONS
http_communication_failure = 1
http_invalid_state         = 2
http_processing_failed     = 3.

*   If it worked, set success flag and exit
IF sy–subrc = 0.
gv_retry_success = ‘X’.
EXIT.
ENDIF.

ENDDO.
ENDFORM.                    ” HTTP_RECEIVE_RETRY
**&———————————————————————*
**&      Form  SAVE_HTTP_STATUS
**&———————————————————————*
**       text
**———————————————————————-*
**      –>P_C_SORTED_PACK_ORDER  text
**———————————————————————-*
FORM save_http_status  USING    p_c_sorted_pack_order.
DATA : lv_err_string TYPE string,
lv_ret_code   TYPE sy–subrc,
ls_zhd_error_log LIKE zhd_error_log,
lv_response TYPE string.

* Only continue if logging is turned on
CHECK gv_logsave = ‘X’.

* HTTP Status
http_client->response->get_status(
IMPORTING
code   = lv_ret_code
reason = lv_err_string
).

* Check for any response data
lv_response = http_client->response->get_cdata( ).

* Ensure there is something to log
IF NOT lv_ret_code IS INITIAL OR NOT lv_err_string IS INITIAL
OR NOT lv_response IS INITIAL.

CLEAR ls_zhd_error_log.

*   Write error to table
ls_zhd_error_log–vbeln      = p_aplid.
ls_zhd_error_log–type       = ‘E’.
*    ls_zhd_error_log-id         = p_id.
ls_zhd_error_log–zdate      = sy–datum.
ls_zhd_error_log–ztime      = sy–uzeit.
ls_zhd_error_log–message    = lv_response.
ls_zhd_error_log–message_v1 = lv_ret_code.
ls_zhd_error_log–message_v2 = lv_err_string.
ls_zhd_error_log–message_v3 = sy–host.              ” DECK924012

INSERT into zhd_error_log values ls_zhd_error_log.

ENDIF.
ENDFORM.                    ” SAVE_HTTP_STATUS

Conclusion:

It is direct call API from ABAP. Hope this useful to you. Thanks