Add bazel php:release target for PECL tgz using generated package.xml

BUILD.bazel

@@ -578,3 +578,10 @@ pkg_files(
     ],
     visibility = ["//pkg:__pkg__"],
 )
+
+# Version JSON file for release
+filegroup(
+    name = "version_json",
+    srcs = ["version.json"],
+    visibility=["//visibility:public"],
+)

php/ext/google/protobuf/BUILD.bazel

@@ -0,0 +1,54 @@
+
+# Protobuf PHP extension (PECL)
+load("@rules_pkg//:mappings.bzl", "pkg_files", "pkg_filegroup", "strip_prefix")
+
+filegroup(
+  name = "template_package_xml",
+  srcs = ["template_package.xml"],
+)
+
+pkg_files(
+  name = "utf8_range_files",
+  srcs = [
+    "@utf8_range//:utf8_range_srcs",
+    "@utf8_range//:LICENSE",
+  ],
+)
+
+pkg_files(
+  name = "protobuf_files",
+  srcs = glob([
+    "*.h",
+    "*.c",
+  ]) + [
+    "//:LICENSE",
+    "config.m4",
+    "wkt.inc",
+  ],
+)
+
+pkg_filegroup(
+  name = "release_files",
+  srcs = [
+    ":protobuf_files",
+    ":utf8_range_files",
+  ],
+)
+
+genrule(
+    name = "pecl_dist",
+    srcs = [
+      ":release_files",
+      ":template_package_xml",
+      "//:version_json",
+    ],
+    outs = ["package.xml"],
+    cmd = " ".join([
+      "$(location :generate_package_xml.sh)",
+      "$(location :template_package_xml)",
+      "$(location //:version_json)",
+      "$$(echo $(locations :release_files) | sed -e 's; ;,;g')",
+      "$(location package.xml)"
+    ]),
+    tools = ["generate_package_xml.sh"],
+)

php/ext/google/protobuf/generate_package_xml.sh

@@ -0,0 +1,42 @@
+#!/bin/bash
+
+template_package_xml=$1
+version_json=$2
+release_files=$3
+out=$4
+
+date=$(date +%Y-%m-%d)
+time=$(date +%H:%M:%S)
+
+php_version_json=$(
+    cat $version_json |
+    python -c "import json, sys; v=json.load(sys.stdin); print(v.popitem()[1]['languages']['php'])")
+php_version_array=(${php_version_json//-rc/ })
+api_version=${php_version_array[0]}
+if [ ${#php_version_array[@]} -eq 2 ]; then
+    rc=${php_version_array[1]}
+    release_version=${api_version}RC${rc}
+    stability='beta'
+else
+    release_version=${api_version}
+    stability='stable'
+fi
+
+files="\\n"
+for file in ${release_files//,/ }; do
+    name=$(echo $file | sed -e 's;php/ext/google/protobuf/;;')
+    if [[ $name =~ LICENSE$ ]]; then
+      role='doc'
+    else
+      role='src'
+    fi
+    files+="    <file baseinstalldir=\"/\" name=\"${name}\" role=\"${role}\"/>\\n"
+done
+
+cat $template_package_xml |
+sed -e "s;TEMPLATE_DATE;${date};" |
+sed -e "s;TEMPLATE_TIME;${time};" |
+sed -e "s;TEMPLATE_PHP_RELEASE;${release_version};" |
+sed -e "s;TEMPLATE_PHP_API;${api_version};" |
+sed -e "s;TEMPLATE_PHP_STABILITY;${stability};g" |
+sed -e "s;TEMPLATE_FILES;${files};" > $out