B4X Requires Chilkat v11.5.0+

curl with Variable Substitution in the Request Body

See more CURL Examples

This example demonstrates using variables located in the request body with the {{variable_name}} syntax. B4X

Dim success As Boolean = False

'  Variables can also be used within the HTTP request body.
'  Variable names are enclosed between {{ and }}

'  Here is a curl command with two variables {{name}} and {{age}} located in the data.

'  curl -X POST https://api.example.com/data \
'    -H "Content-Type: application/json" \
'    -d '{"name":"{{name}}","age":{{age}}}'

Dim sbCurl As ChilkatStringBuilder
sbCurl.Initialize
sbCurl.AppendLn("curl -X POST https://api.example.com/data \")
sbCurl.AppendLn("  -H " & Chr(34) & "Content-Type: application/json" & Chr(34) & " \")
sbCurl.AppendLn("  -d '{" & Chr(34) & "name" & Chr(34) & ":" & Chr(34) & "{{name}}" & Chr(34) & "," & Chr(34) & "age" & Chr(34) & ":{{age}}}'")

Dim curl As ChilkatHttpCurl
curl.Initialize("curl")

'  Provide values for variables.
curl.SetVar("name", "Alice")
curl.SetVar("age", "30")

'  To demonstrate how the variables are replaced, this example does not execute the curl command. 
'  Instead, it generates the raw HTTP request that would be sent if the curl command were run.
Dim sbRawRequest As ChilkatStringBuilder
sbRawRequest.Initialize
success = curl.ToRawRequest(sbCurl.GetAsString, sbRawRequest)
If success = False Then
    Log(curl.LastErrorText)
    Return
End If


Log(sbRawRequest.GetAsString)

'  Output:

'  POST /data HTTP/1.1
'  Host: api.example.com
'  Content-Type: application/json
'  Content-Length: 25
'  
'  {"name":"Alice","age":30}

'  --------------------------------------------------------------------------------------------------
'  Note: Variable substitution in the request body can be turned off by 
'  setting the EnableBodyVars property equal to False

curl.EnableBodyVars = False

success = curl.ToRawRequest(sbCurl.GetAsString, sbRawRequest)
If success = False Then
    Log(curl.LastErrorText)
    Return
End If


Log(sbRawRequest.GetAsString)

'  The raw request with body variable substitution disable:

'  Host: api.example.com
'  Content-Type: application/json
'  Content-Length: 33
'  
'  {"name":"{{name}}","age":{{age}}}