How to export certificates from Traefik certificate store

Traefik stores certificates as base64 encoded X.509 certificates and keys inside the certificate store.

This is a python script to export certificate from Traefik certificate store .json file:

import json
import base64

# Read Traefik ACME JSON
with open("acme.json") as acme_file:
    acme = json.load(acme_file)

# Select certificates from a specific resolver
resolver_name = "my-resolver"
certificates = acme[resolver_name]["Certificates"]

# Find the specific certificate we are looking for
certificate = [certificate for certificate in certificates if "myddomain.com" in certificate["domain"].get("sans", [])][0]

# Extract X.509 certificate data
certificate_data = base64.b64decode(certificate["certificate"])
key_data = base64.b64decode(certificate["key"])

# Export certificate and key to file
with open("certificate.pem", "wb") as certfile:
    certfile.write(certificate_data)

with open("key.pem", "wb") as keyfile:
    keyfile.write(key_data)

Note that depending on what is the primary name for your certificate, you might need to use

if "myddomain.com" == certificate["domain"]["main"]

instead of

if "myddomain.com" in certificate["domain"].get("sans", [])