Validate a JWS with a Public Key

See more JSON Web Signatures (JWS) Examples

Demonstrates Jws.SetPublicKey, which sets the public key used to validate a signature of a loaded JWS.

The file path is relative to the application's current working directory. An absolute path may also be used. Supply the path appropriate to your own environment.

local chilkat = require("chilkat")

local jws = chilkat.Jws.new()

-- Load the JWS compact serialization.
local jwsCompact = "eyJhbGciOiJIUzI1NiJ9.VGhpcyBpcyB0aGUgY29udGVudCB0byBzaWduLg.<signature>"
local success = jws:load_jws(jwsCompact)
if not success then
    print(jws.last_error_text)
    return
end

-- The file path is relative to the application's current working directory.  An absolute path
-- may also be used.  Supply the path appropriate to your own environment.
-- Load the signer's public key and set it for validating signature 0.
local pubKey = chilkat.PublicKey.new()
success = pubKey:load_from_file("qa_data/signer_pubkey.pem")
if not success then
    print(pubKey.last_error_text)
    return
end

success = jws:set_public_key(0, pubKey)
if not success then
    print(jws.last_error_text)
    return
end

-- Validate the signature.  Validate returns 1 when valid, 0 when not, or a negative value on error.
local v = jws:validate(0)
if v < 0 then
    print(jws.last_error_text)
    return
end

if v ~= 1 then
    print("The signature is not valid.")
    return
end

print("The signature is valid.")