fix docker images to work with cql-io-1.1.0 (#697)

* Cleanup Dockerfiles.

* Dockerfile.prebuilder: pull in unreleased stack to fix a bug.

* Use system-ghc.

build/alpine/Dockerfile.builder

@@ -14,6 +14,9 @@ WORKDIR /
 #
 # Finally, we build docs for haskell-src-exts without hyperlinking enabled
 # to avoid a Haddock segfault. See https://github.com/haskell/haddock/issues/928
+#
+# Note: git, ncurses, sed are added here for historical reasons; since
+# roughly 2019-03-28, they are included in prebuilder as well.
 
 RUN apk add --no-cache git ncurses sed && \
     git clone -b develop https://github.com/wireapp/wire-server.git && \

build/alpine/Dockerfile.prebuilder

@@ -33,10 +33,23 @@ RUN apk add --no-cache \
         llvm-libunwind-dev \
         bash \
         xz \
-        libxml2-dev
+        libxml2-dev \
+        git \
+        ncurses \
+        sed
 
 # get static version of Haskell Stack and use system ghc by default
 ARG STACK_ALPINE_VERSION=1.9.1
 RUN curl -sSfL https://github.com/commercialhaskell/stack/releases/download/v${STACK_ALPINE_VERSION}/stack-${STACK_ALPINE_VERSION}-linux-x86_64-static.tar.gz \
     | tar --wildcards -C /usr/local/bin --strip-components=1 -xzvf - '*/stack' && chmod 755 /usr/local/bin/stack && \
     stack config set system-ghc --global true
+
+# upgrade stack to current master (2019-03-28).  this fixes an issue
+# with building internal libraries as used in cql-io-1.1.0.
+# details: https://github.com/commercialhaskell/stack/pull/4596
+RUN git clone https://github.com/commercialhaskell/stack && \
+    cd stack && \
+    git checkout f0b66a1ab60fb5be85f6cb60491915bf53d3cd3c && \
+    sed -i -e 's/lts-12.20/lts-12.14/' snapshot-lts-12.yaml && \
+    stack install --system-ghc --stack-yaml=stack-lts-12.yaml --system-ghc && \
+    cp /root/.local/bin/stack /usr/local/bin/stack