Read the REST Response Body in Chunks

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Demonstrates Rest.ReadRespChunkBd, which reads the response body one chunk at a time, appending each chunk to a BinData. A return value of 0 signals the body is complete, while -1 indicates a read failure.

require 'chilkat'

success = false

rest = Chilkat::CkRest.new()
bTls = true
bAutoReconnect = true
success = rest.Connect("example.com",443,bTls,bAutoReconnect)
if (success == false)
    print rest.lastErrorText() + "\n";
    exit
end

success = rest.SendReqNoBody("GET","/api/largefile")
if (success == false)
    print rest.lastErrorText() + "\n";
    exit
end

statusCode = rest.ReadResponseHeader()
if (statusCode < 0)
    print rest.lastErrorText() + "\n";
    exit
end

#  Check for the expected success status code.  If the response is not 200, the body is likely
#  error text formatted as JSON, XML, or HTML rather than the expected content.  In that case read
#  the body as text, report it, and return.
if (statusCode != 200)
    sbError = Chilkat::CkStringBuilder.new()
    success = rest.ReadRespSb(sbError)
    if (success == false)
        print rest.lastErrorText() + "\n";
        exit
    end

    print "Request failed with status code " + statusCode.to_s() + "\n";
    print sbError.getAsString() + "\n";
    exit
end

#  The status code is 200.  Read the response body in chunks, appending each chunk to the BinData.
#  Each call waits until at least the requested number of bytes is available, unless the response
#  ends first.  A return value of 0 means the final bytes were returned and the body is complete;
#  -1 indicates a read failure.
bdBody = Chilkat::CkBinData.new()
chunkResult = rest.ReadRespChunkBd(8192,bdBody)
while chunkResult > 0
    chunkResult = rest.ReadRespChunkBd(8192,bdBody)
end
if (chunkResult < 0)
    print rest.lastErrorText() + "\n";
    exit
end

print "Received " + bdBody.get_NumBytes().to_s() + " bytes." + "\n";