Automate release process (#1852)

scripts/tag.sh

@@ -0,0 +1,40 @@
+#!/bin/bash
+
+set -e
+
+help() {
+    cat <<- EOF
+Usage: TAG=tag $0
+
+Creates git tags for public Go packages.
+
+VARIABLES:
+  TAG        git tag, for example, v1.0.0
+EOF
+    exit 0
+}
+
+if [ -z "$TAG" ]
+then
+    printf "TAG env var is required\n\n";
+    help
+fi
+
+if ! grep -Fq "\"${TAG#v}\"" version.go
+then
+    printf "version.go does not contain ${TAG#v}\n"
+    exit 1
+fi
+
+PACKAGE_DIRS=$(find . -mindepth 2 -type f -name 'go.mod' -exec dirname {} \; \
+  | grep -E -v "example|internal" \
+  | sed 's/^\.\///' \
+  | sort)
+
+git tag ${TAG}
+
+for dir in $PACKAGE_DIRS
+do
+    printf "tagging ${dir}/${TAG}\n"
+    git tag ${dir}/${TAG}
+done