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Tcl

curl POST with JSON Input and JSON Output

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Demonstrates running a simple curl command with JSON input and JSON output.

Chilkat Tcl Downloads

Tcl

load ./chilkat.dll

set success 0

# Run the following curl command

#  curl -X POST https://httpbin.org/post \
#       -H "Content-Type: application/json" \
#       -d '{
#             "title": "foo",
#             "body": "bar",
#             "userId": 1
#           }'

# The backslashes at the end of lines are not required.  Chilkat ignores them if present.
set sbTargetCurl [new_CkStringBuilder]

CkStringBuilder_AppendLn $sbTargetCurl " curl -X POST https://httpbin.org/post \\"
CkStringBuilder_AppendLn $sbTargetCurl "      -H \"Content-Type: application/json\" \\"
CkStringBuilder_AppendLn $sbTargetCurl "      -d '{"
CkStringBuilder_AppendLn $sbTargetCurl "            \"title\": \"foo\","
CkStringBuilder_AppendLn $sbTargetCurl "            \"body\": \"bar\","
CkStringBuilder_AppendLn $sbTargetCurl "            \"userId\": 1"
CkStringBuilder_AppendLn $sbTargetCurl "          }'"

set httpCurl [new_CkHttpCurl]

# Run the curl command.
set success [CkHttpCurl_DoYourThing $httpCurl [CkStringBuilder_getAsString $sbTargetCurl]]
if {$success == 0} then {
    puts [CkHttpCurl_lastErrorText $httpCurl]
    delete_CkStringBuilder $sbTargetCurl
    delete_CkHttpCurl $httpCurl
    exit
}

set responseJson [new_CkJsonObject]

CkJsonObject_put_EmitCompact $responseJson 0

CkHttpCurl_GetResponseJson $httpCurl $responseJson

set statusCode [CkHttpCurl_get_StatusCode $httpCurl]
puts "response status code: $statusCode"

puts [CkJsonObject_emit $responseJson]

# Output:

# response status code: 200
# {
#   "args": {},
#   "data": "{\r\n            \"title\": \"foo\",\r\n            \"body\": \"bar\",\r\n            \"userId\": 1\r\n          }",
#   "files": {},
#   "form": {},
#   "headers": {
#     "Content-Length": "96",
#     "Content-Type": "application/json",
#     "Host": "httpbin.org",
#     "X-Amzn-Trace-Id": "Root=1-69e8db8b-459b3bdf7b7a3bc749184968"
#   },
#   "json": {
#     "body": "bar",
#     "title": "foo",
#     "userId": 1
#   },
#   "origin": "123.222.222.222",
#   "url": "https://httpbin.org/post"
# }

# ----------------------------------------------------------------------------------
# Another example:

# curl -X POST https://postman-echo.com/post \
#      -H "Content-Type: application/json" \
#      -d '{"foo":"bar"}'

set targetCurl "curl -X POST https://postman-echo.com/post -H \"Content-Type: application/json\" -d '{\"foo\":\"bar\"}'"

# Run the curl command.
set success [CkHttpCurl_DoYourThing $httpCurl $targetCurl]
if {$success == 0} then {
    puts [CkHttpCurl_lastErrorText $httpCurl]
    delete_CkStringBuilder $sbTargetCurl
    delete_CkHttpCurl $httpCurl
    delete_CkJsonObject $responseJson
    exit
}

CkHttpCurl_GetResponseJson $httpCurl $responseJson

set statusCode [CkHttpCurl_get_StatusCode $httpCurl]
puts "response status code: $statusCode"

puts [CkJsonObject_emit $responseJson]

# Output:

# response status code: 200
# {
#   "args": {},
#   "data": {
#     "foo": "bar"
#   },
#   "files": {},
#   "form": {},
#   "headers": {
#     "host": "postman-echo.com",
#     "content-length": "13",
#     "content-type": "application/json",
#     "x-forwarded-proto": "https",
#     "accept-encoding": "gzip, br"
#   },
#   "json": {
#     "foo": "bar"
#   },
#   "url": "https://postman-echo.com/post"
# }

delete_CkStringBuilder $sbTargetCurl
delete_CkHttpCurl $httpCurl
delete_CkJsonObject $responseJson