supply docker args for remote execution

[errordeveloper]

For example, one has to pass --tlscert and --tlskey, when the remote docker host uses self-signed certificate.

[rade]

This isn't necessary for using tls.

What other use cases are there?

[grkvlt]

That doesn't work when you don't have a ca.pem file available, which is only required for client certificate authentication. Actually, this (meaning Docker's insistence on the CA certificate) may be a bug in Docker itself, although the obvious workaround is just to add the ca.pem file and get on with my life... Also, it (Docker, not Weave) should really support setting DOCKER_TLS_VERIFY=false having the same meaning as --tlsverify=false since at present any non empty value is equivalent to --tlsverify only.

[rade]

What shall we call this new env var? Note that it is quite different from WEAVE[DNS]_DOCKER_ARGS, since those supply args for run, i.e. coming after run, whereas here we want args for docker itself, i.e. coming before run.

[grkvlt]

@rade @errordeveloper what about DOCKER_CLIENT_ARGS or LOCAL_DOCKER_ARGS to distinguish them from the remote Docker command's arguments?

[rade]

I like DOCKER_CLIENT_ARGS. And we could, if we really felt the need, add a WEAVEEXEC_DOCKER_ARGS for supplying run parameters.

[errordeveloper]

I only wondered if this should passed in before all arguments or after... Docker favours the last occurrence of same argument, isn't it?

[errordeveloper]

My comment was regarding the placement WEAVEEXEC_DOCKER_ARGS, i.e.

@@ -53,6 +53,7 @@ exec_remote() {
         -e WEAVE_CONTAINER_NAME \
         -e DOCKER_BRIDGE \
         -e PROCFS=/hostproc --privileged --net=host \
+        $WEAVEEXEC_DOCKER_ARGS \
         $EXEC_IMAGE --local "$@"
 }

VS

@@ -53,6 +53,7 @@ exec_remote() {
+        $WEAVEEXEC_DOCKER_ARGS \
         -e WEAVE_CONTAINER_NAME \
         -e DOCKER_BRIDGE \
         -e PROCFS=/hostproc --privileged --net=host \
         $EXEC_IMAGE --local "$@"
 }

[rade]

The former. That's where WEAVE_DOCKER_ARGS is placed by the current script.