crtsh

# Interact with Web API
require "crtsh"

api = Crtsh::API.new
api.search("crt.sh")
api.search("crt.sh", match: "LIKE")
api.search("crt.sh", exclude: "expired")
api.search("crt.sh", match: "LIKE", exclude: "expired")

# Interact with DB
# Note that you have to install pg manually
# gem install pg
require "crtsh/db"

db = Crtsh::DB.new
sql = """
SELECT digest(certificate.certificate, 'sha256') sha256
FROM certificate_identity, certificate
WHERE certificate.id = certificate_identity.certificate_id
AND x509_notAfter(certificate.certificate) > statement_timestamp()
AND reverse(lower(certificate_identity.name_value)) LIKE reverse(lower($1))
LIMIT 10
"""
# Crtsh::DB#connection returns PG::Connection
result = db.connection.exec_params(sql, ["github.com"])
p result.values