i am using Gatling 3.0.0 as a plugin in SBT i am configuring the browser as given in the https://gatling.io/docs/current/http/recorder/#recorder under configuration heading after then when i start the recorder using gatling:startRecorder in sbt and try to hit my website https://www.example.com/ Firefox displayed
Did Not Connect: Potential Security Issue
Firefox detected a potential security threat and did not continue to www.mydomain.com because this website requires a secure connection.
www.mydomain.com has a security policy called HTTP Strict Transport Security (HSTS), which means that Firefox can only connect to it securely. You can’t add an exception to visit this site
and here are the exception logs
ioEventLoopGroup-2-1] DEBUG io.netty.handler.ssl.util.InsecureTrustManagerFactory - Accepting a server certificate: CN=www.mydomain.com
14:44:55.604 [nioEventLoopGroup-4-2] DEBUG io.gatling.recorder.http.Mitm$ - Open new server channel
14:44:55.607 [nioEventLoopGroup-4-1] WARN io.netty.channel.DefaultChannelPipeline - An exceptionCaught() event was fired, and it reached at the tail of the pipeline. It usually means the last handler in the pipeline did not handle the exception.
io.netty.handler.codec.DecoderException: javax.net.ssl.SSLHandshakeException: Received fatal alert: bad_certificate
at io.netty.handler.codec.ByteToMessageDecoder.callDecode(ByteToMessageDecoder.java:472)
at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:278)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:362)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:348)
at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:340)
at io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1434)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:362)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:348)
at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:965)
at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:163)
at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:644)
at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:579)
at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:496)
at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:458)
at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:897)
at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
at java.base/java.lang.Thread.run(Thread.java:834)
Caused by: javax.net.ssl.SSLHandshakeException: Received fatal alert: bad_certificate
at java.base/sun.security.ssl.Alert.createSSLException(Alert.java:128)
at java.base/sun.security.ssl.Alert.createSSLException(Alert.java:117)
at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:308)
at java.base/sun.security.ssl.Alert$AlertConsumer.consume(Alert.java:279)
at java.base/sun.security.ssl.TransportContext.dispatch(TransportContext.java:181)
at java.base/sun.security.ssl.SSLTransport.decode(SSLTransport.java:164)
at java.base/sun.security.ssl.SSLEngineImpl.decode(SSLEngineImpl.java:672)
at java.base/sun.security.ssl.SSLEngineImpl.readRecord(SSLEngineImpl.java:627)
at java.base/sun.security.ssl.SSLEngineImpl.unwrap(SSLEngineImpl.java:443)
at java.base/sun.security.ssl.SSLEngineImpl.unwrap(SSLEngineImpl.java:422)
at java.base/javax.net.ssl.SSLEngine.unwrap(SSLEngine.java:634)
at io.netty.handler.ssl.SslHandler$SslEngineType$3.unwrap(SslHandler.java:294)
at io.netty.handler.ssl.SslHandler.unwrap(SslHandler.java:1297)
at io.netty.handler.ssl.SslHandler.decodeJdkCompatible(SslHandler.java:1199)
at io.netty.handler.ssl.SslHandler.decode(SslHandler.java:1243)
at io.netty.handler.codec.ByteToMessageDecoder.decodeRemovalReentryProtection(ByteToMessageDecoder.java:502)
at io.netty.handler.codec.ByteToMessageDecoder.callDecode(ByteToMessageDecoder.java:441)
... 16 common frames omitted
14:44:55.609 [recorder-akka.actor.default-dispatcher-4] DEBUG io.gatling.recorder.http.flows.SecuredNoProxyMitmActor - Server channel 6acf48e4 was closed while in Connected state, closing
14:44:55.622 [recorder-akka.actor.default-dispatcher-2] DEBUG io.gatling.recorder.http.flows.PlainNoProxyMitmActor - serverChannel=8d7b2171 received init request http://detectportal.firefox.com/success.txt, connecting
14:44:55.622 [recorder-akka.actor.default-dispatcher-2] DEBUG io.gatling.recorder.http.flows.PlainNoProxyMitmActor - Connecting to Remote(detectportal.firefox.com,80)
14:44:55.629 [recorder-akka.actor.default-dispatcher-4] INFO akka.actor.RepointableActorRef - Message [io.gatling.recorder.http.flows.MitmMessage$ClientChannelInactive] without sender to Actor[akka://recorder/user/$a#-1754914561] was not delivered. [1] dead letters encountered. If this is not an expected behavior, then [Actor[akka://recorder/user/$a#-1754914561]] may have terminated unexpectedly, This logging can be turned off or adjusted with configuration settings 'akka.log-dead-letters' and 'akka.log-dead-letters-during-shutdown'.
14:44:55.655 [nioEventLoopGroup-2-2] DEBUG io.gatling.recorder.http.Mitm$ - Open new client channel
How did you configured proxy in your firefox? Do you have proxy only for http or also for https? If you are proxing also https requests then in recorder settings you need to switch "HTTPS mode" to "Certificate Authority". There will be a button to generate new certificate authority file that you need to import to your browser (Preferences / Privacy & Security / Certificates / View certificates / Import). After that your browser will know that it can trust Gatling proxy server and you should be able to proxy also ssl requests.