Preface – This post is part of the ABAP Programs series.
In this step we will call the service to get the token and store that token in a global variable for later use.
METHOD get_token.
DATA: lo_http_client TYPE REF TO if_http_client.
DATA: response TYPE string,
lv_url TYPE string.
CONSTANTS: lv_initial_url TYPE string VALUE '<Blockchain Service Link>',
lv_auth TYPE string VALUE 'Basic <your login credentials>'.
"create HTTP client by url
CALL METHOD cl_http_client=>create_by_url
EXPORTING
url = lv_initial_url
IMPORTING
client = lo_http_client
EXCEPTIONS
argument_not_found = 1
plugin_not_active = 2
internal_error = 3
OTHERS = 4.
"Available API Endpoints
"https://blockchain-service.cfapps.sap.hana.ondemand.com/blockchain/proofOfHistory/api/v1
"https://blockchain-service.cfapps.eu10.hana.ondemand.com/blockchain/proofOfHistory/api/v1
"https://blockchain-service.cfapps.us10.hana.ondemand.com/blockchain/proofOfHistory/api/v1
IF sy-subrc <> 0.
"error handling
ENDIF.
"setting request method
lo_http_client->request->set_method('GET').
"adding headers
lo_http_client->request->set_header_field( name = 'Authorization' value = lv_auth ).
"Available Security Schemes for productive API Endpoints
"OAuth 2.0
CALL METHOD lo_http_client->send
EXCEPTIONS
http_communication_failure = 1
http_invalid_state = 2
http_processing_failed = 3
http_invalid_timeout = 4
OTHERS = 5.
IF sy-subrc = 0.
CALL METHOD lo_http_client->receive
EXCEPTIONS
http_communication_failure = 1
http_invalid_state = 2
http_processing_failed = 3
OTHERS = 5.
ENDIF.
IF sy-subrc <> 0.
"error handling
ENDIF.
response = lo_http_client->response->get_cdata( ).
GV_TOKEN = response. "Global Variable
ENDMETHOD.
LV_AUTH (Send Basic Info) : How to send value in to this variable. I mean the format of the data?