Added support for Kafka headers to be passed and retrieved from functions. The headers and supported and work only for Kafka version 0.11.0.0 and higher.
* Optimize router response time by adding update lock
In 0.9.2, the router sends multiple GetServiceForFunction requests to executor
to get the service URL. However, the response time of executor will increase
under high-concurrency situation due to too many requests are waiting for
processing.
To solve the problem, an update lock was added to the router. All of goroutines belongs
to the same function need to grab the update lock before sending the request.
Only the first goroutine which gets the update lock is allowed to send request.
In this way, we reduce the burden of executor and lower the failure rate.
The Round Tripper parameters of timeout, keep alive time and Max retry
times is configured in router system environment.
And they are set to Round Tripper when router service initializing.
This setup new nested structure `tsRoundTripperParams` to transfer them.
For archives bigger than 256K, the Storage service was called from the client side, this needed few environment variables to be set. This change uses port forwarding to achieve the same and does not need environment variables to be set.
It is mandatory (from this release onwards) for function to refer to secrets, config-maps and packages in its own namespace to ensure isolation of users sharing the same cluster.
This change runs a pre-upgrade job to verify function references for all functions created prior to this release and fails the upgrade by printing a list of functions that violate this restriction.
Ingress integration to allow the optional creation of ingress for a given route. The ingress controller needs to be set up by the user separately so that ingress path is accessible outside the cluster.
This feature allows creation of fission objects in different namespaces, in addition to retaining the existing behavior of creating fission objects in default namespace if user doesnt provide one.
It also removes cluster admin roles for fission-fetcher and fission-builder Service Accounts and grants them only those privileges that they need.
The Deployment definition for executor, controller, router contains readines/liveness probes. The port definition for those probes should be numbers, instead of string, i.e. port: "8888" should be port 8888.
