"Performing the SSL/TLS handshake..." blocking other code inside the loop()

[UnknownKhan2023]

22:11:44.896 -> [ 63896][V][ssl_client.cpp:321] stop_ssl_socket(): Cleaning SSL connection.
22:11:44.959 -> [ 63977][V][ssl_client.cpp:62] start_ssl_client(): Free internal heap before TLS 163320
22:11:45.055 -> [ 64069][V][ssl_client.cpp:68] start_ssl_client(): Starting socket
22:11:45.120 -> [ 64215][V][ssl_client.cpp:146] start_ssl_client(): Seeding the random number generator
22:11:45.215 -> [ 64233][V][ssl_client.cpp:155] start_ssl_client(): Setting up the SSL/TLS structure...
22:11:45.312 -> [ 64325][D][ssl_client.cpp:176] start_ssl_client(): WARNING: Skipping SSL Verification. INSECURE!
22:11:45.408 -> [ 64428][V][ssl_client.cpp:254] start_ssl_client(): Setting hostname for TLS session...
22:11:45.504 -> [ 64521][V][ssl_client.cpp:269] start_ssl_client(): Performing the SSL/TLS handshake...
22:11:56.096 -> [ 75237][V][ssl_client.cpp:290] start_ssl_client(): Verifying peer X.509 certificate...
22:11:56.192 -> [ 75237][V][ssl_client.cpp:298] start_ssl_client(): Certificate verified.
22:11:56.256 -> [ 75273][V][ssl_client.cpp:313] start_ssl_client(): Free internal heap after TLS 119584

"Performing the SSL/TLS handshake..." blocking code running inside loop() function,
Is there any way to async the SSL/TLS handshake...?

[mobizt]

No, you have to wait.

[mobizt]

The way you can reduce the handshake time is session resumption that supported by BearSSL in ESP8266 WiFiClientSecure.

For ESP32, I recommend using this ESP_SSLClient as external SSL Client.

See this example for session resumption.

In the next version of this Firebase library, ESP_SSLClient will be used internally instead of WiFiClientSecure.