Bad Request error when calling HTTP_POST? - http-post

Question

I have a question about the SAP Function Module "http_post".
I just want to post a short message (msg) out of the SAP to a Push Notification Server (pushd-Github-Projekt) I installed before. Now I'm not sure how to pass the message.
I tested the FM with the test-symbol:
CALL FUNCTION 'HTTP_POST'
exporting
ABSOLUTE_URI = uri " Uniform Resource Identifier (RFC 1945)
* REQUEST_ENTITY_BODY_LENGTH = 14 "request_entity_body_length
* RFC_DESTINATION = " RFC Destination
* PROXY = " HTTP Proxy Rechner
* PROXY_USER = " Benutzername auf dem Proxy Rechner
* PROXY_PASSWORD = " Passwort auf dem Proxy Rechner
* USER = " Benutzername auf dem HTTP Server
* PASSWORD = " Passwort auf dem HTTP Server
* BLANKSTOCRLF = " Blanks in CRLF konvertieren im Entity Body
* importing
* STATUS_CODE = " Statuscode ( 2xx = OK )
* STATUS_TEXT = " Text zum Statuscode
* RESPONSE_ENTITY_BODY_LENGTH = " Länge vom Response-Entity-Body
tables
REQUEST_ENTITY_BODY = '{"msg":"test"}' "request_entity_body
RESPONSE_ENTITY_BODY = '' " Response-Entity-Body Daten
RESPONSE_HEADERS = '' " Header Zeilen vom Response
REQUEST_HEADERS = 'Content-Type: application/json' "request_headers
* exceptions
* CONNECT_FAILED = 1
* TIMEOUT = 2
* INTERNAL_ERROR = 3
* TCPIP_ERROR = 4
* SYSTEM_FAILURE = 5
* COMMUNICATION_FAILURE = 6
* OTHERS = 7
.
I know my values are no tables, but I tested it with the test-symbol, where you can write the values directly in a table.
When I start the FM, I get an Bad Request error in the SAP
and this error at the push notification server:
SyntaxError: Unexpected token
at Object.parse (native)
at IncomingMessage.<anonymous> ...Path from the pushd..
express\node_modules\connect\lib\middleware\json.js:76:27
at incomingMessage.EventEmitter.emit events.js:92:17
at _stream:readable.js:919:16
at process._tickCallback <node.js:419:13>
Can anyone help me how to pass the request to the FM HTTP-Post? It has to be sth. with msg, because otherwise the Push-Notification-Server can't handle it.

Answer 1

In SAP_BASIS release 731 or higher, I would strongly recommend to use the class CL_HTTP_CLIENTfor doing HTTP requests. See here an example report on how to do it. Replace the dummy string http:1.2.3.4:80/testjon/by your URL in question.
report z_test_http_post.
start-of-selection.
perform start.
* ---
form start.
data: lv_status type i,
lv_error_occurred type flag,
lv_error_msg type string,
lv_response_body type string.
perform send_json using
'http://1.2.3.4:80/testjson/' " Use your URL here
'{"hello":"world"}' " Use your JSON here
changing lv_status lv_response_body
lv_error_occurred
lv_error_msg.
* Show result
format color col_heading.
write: / 'Response status:', lv_status.
if lv_error_occurred = 'X'.
format color col_negative.
write: / 'Error occurred:', lv_error_msg.
endif.
format color col_normal.
write: / 'Response:', lv_response_body.
endform. "start
form send_json using iv_url type string
iv_json_data type string
changing cv_status type i
cv_response_body type string
cv_error_occurred type flag
cv_error_msg type string.
data: lo_client type ref to if_http_client.
clear: cv_error_msg,
cv_status,
cv_error_occurred,
cv_error_msg.
if iv_url is initial.
* No URL passed
message e349(sbds) into cv_error_msg.
cv_error_occurred = 'X'.
return.
endif.
call method cl_http_client=>create_by_url
exporting
url = iv_url
importing
client = lo_client
exceptions
argument_not_found = 1
plugin_not_active = 2
internal_error = 3
others = 4.
if sy-subrc ne 0.
message id sy-msgid type sy-msgty number sy-msgno
with sy-msgv1 sy-msgv2 sy-msgv3 sy-msgv4
into cv_error_msg.
cv_error_occurred = 'X'.
return.
endif.
lo_client->request->set_cdata( iv_json_data ).
lo_client->request->set_content_type( 'application/json' ).
lo_client->request->set_method( 'POST' ).
call method lo_client->send
exceptions
http_communication_failure = 1
http_invalid_state = 2
http_processing_failed = 3
others = 4.
if sy-subrc ne 0.
lo_client->get_last_error( importing message = cv_error_msg ).
cv_error_occurred = 'X'.
return.
endif.
lo_client->receive( exceptions others = 1 ).
if sy-subrc ne 0.
lo_client->get_last_error( importing message = cv_error_msg ).
cv_error_occurred = 'X'.
return.
endif.
cv_response_body = lo_client->response->get_cdata( ).
lo_client->response->get_status( importing code = cv_status ).
endform.