(Tcl) HTTP POST and Stream Response to File

Demonstrates how to send an HTTP POST and stream the response body directly to a file.

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load ./chilkat.dll

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

set rest [new_CkRest]

set url [new_CkUrl]

# This URL will emit a response that echos the query params (name and age)
CkUrl_ParseUrl $url "https://www.chilkatsoft.com/readPost.asp"

# Connect to the web server
set bAutoReconnect 1
set success [CkRest_Connect $rest [CkUrl_host $url] [CkUrl_get_Port $url] [CkUrl_get_Ssl $url] $bAutoReconnect]
if {$success != 1} then {
    puts [CkRest_lastErrorText $rest]
    delete_CkRest $rest
    delete_CkUrl $url
    exit
}

CkRest_AddQueryParam $rest "name" "John"
CkRest_AddQueryParam $rest "age" "33"

#  Send the HTTP POST.
set success [CkRest_SendReqFormUrlEncoded $rest "POST" [CkUrl_path $url]]
if {$success != 1} then {
    puts [CkRest_lastErrorText $rest]
    delete_CkRest $rest
    delete_CkUrl $url
    exit
}

# Read the response header.
set responseStatusCode [CkRest_ReadResponseHeader $rest]
if {$responseStatusCode < 0} then {
    puts [CkRest_lastErrorText $rest]
    delete_CkRest $rest
    delete_CkUrl $url
    exit
}

puts "Response status code = $responseStatusCode"

# We expect a 200 response status if the file data is coming.
# Otherwise, we'll get a string response body with an error message(or no response body).
if {$responseStatusCode == 200} then {

    set bodyStream [new_CkStream]

    # The stream's sink will be a file.
    CkStream_put_SinkFile $bodyStream "qa_output/out.txt"

    # Read the response body to the stream.  Given that we've
    # set the stream's sink to a file, it will stream directly
    # to the file.
    set success [CkRest_ReadRespBodyStream $rest $bodyStream 1]
    if {$success != 1} then {
        puts [CkRest_lastErrorText $rest]
        delete_CkRest $rest
        delete_CkUrl $url
        delete_CkStream $bodyStream
        exit
    }

    puts "Successfully streamed the response to a file."

} else {
    set errResponse [CkRest_readRespBodyString $rest]
    if {[CkRest_get_LastMethodSuccess $rest] != 1} then {
        puts [CkRest_lastErrorText $rest]
    }     else {
        puts "$errResponse"
    }

}


delete_CkRest $rest
delete_CkUrl $url
delete_CkStream $bodyStream