Install core origin public key in devshell.

This is a temporary measure until public origin keys are downloaded on
package installations. Its implementation is non-straight forward
because we're caching the `/hab/cache/keys` directory with a mounted
data volume. When the Docker container comes up, this directory is bind
mounted over and the underlying directory contents is masked out.

Pull request: #457
Approved by: reset

.dockerignore

@@ -9,6 +9,7 @@ images
 log
 plans
 support
+!support/init.sh
 vendor
 web
 *.md

Dockerfile

@@ -40,9 +40,14 @@ RUN cargo install protobuf
 COPY .delivery/scripts/ssh_wrapper.sh /usr/local/bin
 COPY .delivery/scripts/git_src_checkout.sh /usr/local/bin
 COPY components/studio/install.sh /tmp
+COPY support/init.sh /init.sh
 RUN /tmp/install.sh \
   && hab-bpm install core/busybox-static \
+  && (cd /tmp && curl -sLO https://s3-us-west-2.amazonaws.com/fnichol-lfs-tools/core-20160423193745.pub) \
+  && chmod 755 /init.sh \
   && rm -f /tmp/install.sh /hab/cache/artifacts/*
 
 WORKDIR /src
+# This entrypoint is temporary until origin key download on install is implemented
+ENTRYPOINT ["/init.sh"]
 CMD ["bash"]

support/init.sh

@@ -0,0 +1,8 @@
+#!/bin/sh
+set -e
+
+if [ ! -f /hab/cache/keys/core-20160423193745.pub ]; then
+  cp -v /tmp/core-20160423193745.pub /hab/cache/keys
+fi
+
+exec "$@"