How to provide a ca.cert file to HTTP.jl requests (I don't have a key file)

the documentation lists a couple of ssl configs which can be set a for a http request:

SSL arguments:

  • require_ssl_verification = NetworkOptions.verify_host(host), pass MBEDTLS_SSL_VERIFY_REQUIRED to the mbed TLS library. “… peer must present a valid certificate, handshake is aborted if verification failed.”
  • sslconfig = SSLConfig(require_ssl_verification)
  • socket_type_tls = MbedTLS.SSLContext, the type of socket to use for TLS connections. Defaults to MbedTLS.SSLContext. Also supported is passing socket_type_tls = OpenSSL.SSLStream. To change the global default, set HTTP.SOCKET_TYPE_TLS = OpenSSL.SSLStream.

I found that there is a MbedTLS.SSLConfig(cacert, keyfile), however I am on kubernetes and I only have the ca.cert file and no keyfile.

With curl I have the --cacert option, how to do this with HTTP.jl and MbedTLS?