frunner

Scope

This provides an HTTP server which executes the configured binary with the input from the request and returns the result. Data is passed around via io.Reader/io.Writer so that data sized > available memory is possible.

Additionally a interface is provided to enable developers to create customized versions of the frunner to prevent forking a process for every call.

OpenFaaS

This is intended to be used with openfaas and can hopefully be used as a replacement for the fwatchdog. This is heavily inspired by openfaas/faas/watchdog and all credits for this are going to @alexellis. Thank you for your fantastic work :)

Install

go get -d github.com/trusch/btrfaas/frunner/cmd/frunner
cd ${GOPATH}/github.com/trusch/btrfaas/frunner
make all
make install

Configuration

frunner --help
Usage of frunner:
  -b, --buffer                  buffer output before writing
  -t, --call-timeout duration   function call timeout
  -l, --http-addr string        http listen address (default ":8080")
  -g, --grpc-addr string        grpc listen address (default ":2424")
  -h, --http-timeout duration   http timeout for reading request headers (default 1s)
      --read-limit int          limit the amount of data which can be contained in a requests body (default -1)

A typical call would look like this: frunner --http-addr :8080 -- cat -

This would result in an gRPC and HTTP echo server ("cat -" just rewrites stdin to stdout) Everything after the "--" is interpreted as the executable and its arguments

You can also configure the frunner via environment variables:

# export FRUNNER_CALL_TIMEOUT="5s"
# export FRUNNER_HTTP_TIMEOUT="1s"
# export FRUNNER_HTTP_ADDRESS=":8080"
# export FRUNNER_GRPC_ADDRESS=":2424"
# export FRUNNER_READ_LIMIT=1024
# export FRUNNER_BUFFER=false
export FRUNNER_CMD="sha512sum"
frunner