support aliyun mirror

Dockerfile

@@ -3,14 +3,22 @@ FROM openjdk:8-jdk-alpine
 MAINTAINER arthas anjia0532
 
 ARG ARTHAS_VERSION="3.0.5"
+ARG MIRROR=false
 
-# https://github.com/docker-library/openjdk/issues/76
-RUN apk add --no-cache tini
+ENV MAVEN_HOST=https://repo1.maven.org/maven2 \
+    ALPINE_HOST=dl-cdn.alpinelinux.org \
+    MIRROR_MAVEN_HOST=http://maven.aliyun.com/repository/public \
+    MIRROR_ALPINE_HOST=mirrors.aliyun.com 
+
+# if use mirror change to aliyun mirror site
+RUN if $MIRROR; then MAVEN_HOST=${MIRROR_MAVEN_HOST} ;ALPINE_HOST=${MIRROR_ALPINE_HOST} ; sed -i "s/dl-cdn.alpinelinux.org/${ALPINE_HOST}/g" /etc/apk/repositories ; fi && \
+    # https://github.com/docker-library/openjdk/issues/76
+    apk add --no-cache tini && \ 
+    # download & install arthas
+    wget -qO /tmp/arthas.zip "${MAVEN_HOST}/com/taobao/arthas/arthas-packaging/${ARTHAS_VERSION}/arthas-packaging-${ARTHAS_VERSION}-bin.zip" && \
+    mkdir -p /opt/arthas && \
+    unzip /tmp/arthas.zip -d /opt/arthas && \
+    rm /tmp/arthas.zip
 
 # Tini is now available at /sbin/tini
 ENTRYPOINT ["/sbin/tini", "--"]
-
-RUN wget -qO- -O /tmp/arthas.zip https://repo1.maven.org/maven2/com/taobao/arthas/arthas-packaging/${ARTHAS_VERSION}/arthas-packaging-${ARTHAS_VERSION}-bin.zip && \
-			mkdir -p /opt/arthas && \
-			unzip /tmp/arthas.zip -d /opt/arthas && \
-			rm /tmp/arthas.zip