dockerfile: include zero-config mysql client

Fixes #733

With this change, users won't even have to install the MySQL client
on their machines or care about setting the parameters every single
time they use it. By just `docker exec -it $IMAGE_NAME mysql` it
will connect to gitbase without requiring any kind of configuration.

Connection details are stored in `$HOME/.my.cnf`, which is generated
at the start of the gitbase server. Because gitbase user and password
can change when you run it, not only when you build the image, this
needs to be done on startup. That's why `init.sh` has been included,
which just creates the configuration for MySQL client and starts the
gitbase server.

Signed-off-by: Miguel Molina <[email protected]>

Dockerfile

@@ -17,24 +17,25 @@ RUN go build -ldflags="-X main.version=$(cat version.txt || echo "undefined") -X
 #=================================
 FROM alpine:3.8
 
+RUN apk add --no-cache mysql-client
+
 RUN mkdir -p /opt/repos
 
-ENV GITBASE_USER=root
-ENV GITBASE_PASSWORD=""
-ENV GITBASE_REPOS=/opt/repos
 EXPOSE 3306
 
 ENV TINI_VERSION v0.18.0
 ADD https://github.com/krallin/tini/releases/download/${TINI_VERSION}/tini-static-amd64 /tini
 RUN chmod +x /tini
 ENTRYPOINT ["/tini", "--"]
 
+ENV GITBASE_USER=root
+ENV GITBASE_PASSWORD=""
+ENV GITBASE_REPOS=/opt/repos
+ENV MYSQL_HOST=127.0.0.1
+
 # copy build artifacts
 COPY --from=builder /bin/gitbase /bin/gitbase
+ADD init.sh ./init.sh
+RUN chmod +x ./init.sh
 
-CMD /bin/gitbase server -v \
-    --host=0.0.0.0 \
-    --port=3306 \
-    --user="$GITBASE_USER" \
-    --password="$GITBASE_PASSWORD" \
-    --directories="$GITBASE_REPOS"
+ENTRYPOINT ["./init.sh"]

init.sh

@@ -0,0 +1,14 @@
+#!/bin/sh
+
+cat <<EOT >> "$HOME/.my.cnf"
+[client]
+user=${GITBASE_USER}
+password=${GITBASE_PASSWORD}
+EOT
+
+/tini -s -- /bin/gitbase server -v \
+    --host=0.0.0.0 \
+    --port=3306 \
+    --user="$GITBASE_USER" \
+    --password="$GITBASE_PASSWORD" \
+    --directories="$GITBASE_REPOS"