Lua Requires Chilkat v11.0.0+

Ibanity HTTP Signature for XS2A, Isabel Connect, Ponto Connect

See more Ibanity Examples

Demonstrates how to add a Signature header for Ibanity HTTP requests. Lua

local chilkat = require("chilkat")

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

-- In order to sign your HTTP requests, you have to add 2 headers to the HTTP request: Digest: the digest of the request payload and Signature: the actual signature of the request.

-- POST /xs2a/customer-access-tokens HTTP/1.1
-- Host: api.ibanity.com
-- Content-Type: application/json
-- Digest: SHA-512=z4PhNX7vuL3xVChQ1m2AB9Yg5AULVxXcg/SpIdNs6c5H0NE8XYXysP+DGNKHfuwvY7kxvUdBeoGlODJ6+SfaPg==
-- Ibanity-Idempotency-Key: 61f02718-eeee-46e1-b5eb-e8fd6e799c2d
-- Signature: keyId="62f02718-eeee-46e1-b5eb-e8fd6e799c2e",created=1599659223,algorithm="hs2019",headers="(request-target) host digest (created) ibanity-idempotency-key",signature="SjWJWbWN7i0...zsbM="
--
-- {"data":{"type":"customerAccessToken", "attributes":{"applicationCustomerReference":"15874569"}}}

-- The payload (body) of the above HTTP request is the JSON.
-- Build the JSON above.
-- Use this online tool to generate code from sample JSON:
-- Generate Code to Create JSON
local json = chilkat.JsonObject.new()
json:update_string("data.type", "customerAccessToken")
json:update_string("data.attributes.applicationCustomerReference", "15874569")

local payload = json:emit()
print("payload = " .. payload)

-- Step 1: Build the (created) virtual header

local dtNow = chilkat.DateTime.new()
dtNow:set_from_current_system_time()
local created = dtNow:get_as_unix_time_str(false)
print("created = " .. created)

-- Step 2: Build the Digest header
local crypt = chilkat.Crypt2.new()
crypt.hash_algorithm = "sha512"
crypt.encoding_mode = "base64"
crypt.charset = "utf-8"

local sbDigestHdrValue = chilkat.StringBuilder.new()
sbDigestHdrValue:append("SHA-512=")
sbDigestHdrValue:append(crypt:hash_string_enc(json:emit()))

print(sbDigestHdrValue:get_as_string())

-- Step 3: Build the (request target) virtual header

-- In order to build the signature you will need a virtual header named (request-target) (the parentheses are important).
-- The (request-target) is the string concatenation of the HTTP method (in lowercase) with the path and query parameters.
local request_target = "post /xs2a/customer-access-tokens"

-- Step 4: Build the signing string

-- The signing string is the concatenation of the signed header names (in lowercase) and values separated by a LF.

-- You must always sign the following headers: (request-target), host, (created), digest.
-- If used, you must also sign the authorization header and any ibanity-* headers, such as ibanity-idempotency-key.

local sbSigningString = chilkat.StringBuilder.new()
sbSigningString:append("(request-target): ")
sbSigningString:append_line(request_target, false)
sbSigningString:append("host: ")
sbSigningString:append_line("api.ibanity.com", false)
sbSigningString:append("digest: ")
sbSigningString:append_line(sbDigestHdrValue:get_as_string(), false)
sbSigningString:append("(created): ")
sbSigningString:append_line(created, false)
sbSigningString:append("ibanity-idempotency-key: ")
local idempotencyKey = crypt:generate_uuid()
sbSigningString:append(idempotencyKey)

-- Step 5: Build the signed headers list

-- To allow Ibanity to check the signed headers, you must provide a list of the header names. They should be lowercase and in the same order used to create the signing string.
local signed_headers_list = "(request-target) host digest (created) ibanity-idempotency-key"

-- Step 6: Build the Signature header

-- This is where the real signing happens. The signature header is a combination of several sub-headers -
--
--     keyId: the identifier for the application's signature certificate, obtained from the Developer Portal
--     algorithm: the digital signature algorithm used to generate the signature (must be hs2019)
--     headers: The list of HTTP headers created in step 5
--     signature: the Base64-encoded digital signature of the signing string created in step 4.

local privKey = chilkat.PrivateKey.new()
local success = privKey:load_encrypted_pem_file("my_ibanity_signature_private_key.pem", "pem_password")
if not success then
    print(privKey.last_error_text)
    return
end

local rsa = chilkat.Rsa.new()
rsa.pss_salt_len = 32
rsa.encoding_mode = "base64"
-- Use the RSASSA-PSS signature algorithm
rsa.pkcs_padding = false

success = rsa:use_private_key(privKey)
if not success then
    print(rsa.last_error_text)
    return
end

-- Sign the signing string.
local sigBase64 = rsa:sign_string_enc(sbSigningString:get_as_string(), "sha-256")
if not rsa.last_method_success then
    print(rsa.last_error_text)
    return
end

-- Build the signature header value.
local sbSigHeaderValue = chilkat.StringBuilder.new()
sbSigHeaderValue:append("keyId=\"")
-- Use your identifier for the application's signature certificate, obtained from the Developer Portal
sbSigHeaderValue:append("62f02718-eeee-46e1-b5eb-e8fd6e799c2e")
sbSigHeaderValue:append("\",created=")
sbSigHeaderValue:append(created)
sbSigHeaderValue:append(",algorithm=\"hs2019\",headers=\"")
sbSigHeaderValue:append(signed_headers_list)
sbSigHeaderValue:append("\",signature=\"")
sbSigHeaderValue:append(sigBase64)
sbSigHeaderValue:append("\"")

print(sbSigHeaderValue:get_as_string())