Version docker images

VERSION

@@ -0,0 +1 @@
+0.0.0

build_docker.sh

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+#!/bin/bash
+
+set -o nounset
+set -o errexit
+set -o pipefail
+
+# Compute repo's dir
+DIR=$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )
+
+IMAGE_PREFIX="karalabe/xgo"
+
+function build_image() {
+    local folder=$1
+    local name=$2
+    local version=$3
+
+    docker build -t ${name}:${version} ${folder}
+}
+
+function build_image_file() {
+    local dockerfile=$1
+    local name=$2
+    local version=$3
+
+    local fixed_dockerfile=$(cat ${dockerfile} | sed -E "s/FROM (.*)$/FROM \\1:${version}/")
+
+    echo "${fixed_dockerfile}" | docker build -t "${name}:${version}" -
+}
+
+function get_version() {
+    cat "${DIR}/VERSION"
+}
+
+# subdirs returns a list of directories in a folder
+function subdirs() {
+    local folder=$1
+    bash -c "cd ${folder} && ls -d */" | sed 's/\/$//'
+}
+
+function go_versions() {
+    subdirs "${DIR}/docker" | grep -v base | grep -v latest | sed 's/^go-//'
+}
+
+function main() {
+    # Get ver
+    local version=$(get_version)
+
+    echo "Building base"
+    build_image "${DIR}/docker/base" "${IMAGE_PREFIX}-base" "${version}"
+
+    # Run builds in parallel
+    local N=4
+    local i=0
+    for goVersion in $(go_versions | grep -v ".x"); do
+        ((i=i%N)); ((i++==0)) && wait
+        echo
+        echo "Building ${goVersion}"
+        build_image_file "${DIR}/docker/go-${goVersion}/Dockerfile" "${IMAGE_PREFIX}-${goVersion}" "${version}" &
+    done
+    # Wait for all tasks to be finished
+    wait
+
+    # Build .x versions (quick and easy to build since they simply refer to other images)
+    for goVersion in $(go_versions | grep ".x"); do
+        echo
+        echo "Building ${goVersion}"
+        build_image_file "${DIR}/docker/go-${goVersion}/Dockerfile" "${IMAGE_PREFIX}-${goVersion}" "${version}"
+    done
+
+    # Build go-latest last (since it depends on earlier builds)
+    echo
+    echo "Building latest"
+    build_image_file "${DIR}/docker/go-latest/Dockerfile" "${IMAGE_PREFIX}-latest" "${version}"
+}
+
+# Run main
+main