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Go

curl with Variable Substitution in the Request Body

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

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Go
    success := 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}}}'

    sbCurl := chilkat.NewStringBuilder()
    sbCurl.AppendLn("curl -X POST https://api.example.com/data \\")
    sbCurl.AppendLn("  -H \"Content-Type: application/json\" \\")
    sbCurl.AppendLn("  -d '{\"name\":\"{{name}}\",\"age\":{{age}}}'")

    curl := chilkat.NewHttpCurl()

    // 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.
    sbRawRequest := chilkat.NewStringBuilder()
    success = curl.ToRawRequest(*sbCurl.GetAsString(),sbRawRequest)
    if success == false {
        fmt.Println(curl.LastErrorText())
        sbCurl.DisposeStringBuilder()
        curl.DisposeHttpCurl()
        sbRawRequest.DisposeStringBuilder()
        return
    }

    fmt.Println(*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.SetEnableBodyVars(false)

    success = curl.ToRawRequest(*sbCurl.GetAsString(),sbRawRequest)
    if success == false {
        fmt.Println(curl.LastErrorText())
        sbCurl.DisposeStringBuilder()
        curl.DisposeHttpCurl()
        sbRawRequest.DisposeStringBuilder()
        return
    }

    fmt.Println(*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}}}

    sbCurl.DisposeStringBuilder()
    curl.DisposeHttpCurl()
    sbRawRequest.DisposeStringBuilder()