Lua

Export a Public Key DER as Encoded Text

Demonstrates the Chilkat PublicKey.GetEncoded method, which returns the DER representation encoded as text. The first argument selects the DER representation (as for GetPem) and the second names the binary encoding, such as base64 or hex.

Note: The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background: This returns the raw DER bytes as an encoded string, so the key can travel through a text-only medium without the BEGIN/END armor of PEM. Choosing base64 versus hex is simply a matter of what the consumer expects, and the first argument selects the same DER structures as GetPem.

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Lua

local chilkat = require("chilkat")

-- Load a public key to export.  LoadFromFile inspects the content, so it accepts DER, PEM, XML,
-- JWK, and other supported representations.
local pubKey = chilkat.PublicKey.new()
local success = pubKey:load_from_file("qa_data/public.pem")
if not success then
    print(pubKey.last_error_text)
    return
end

-- Export the DER as text.  The 1st argument selects the DER representation (as for GetPem) and
-- the 2nd names the binary encoding, such as "base64" or "hex".
local preferPkcs1 = false
local encoded = pubKey:get_encoded(preferPkcs1, "base64")
if not pubKey.last_method_success then
    print(pubKey.last_error_text)
    return
end

print(encoded)