Add deb packaging

Signed-off-by: Krsna Mahapatra <keshto@gmail.com>

Makefile

@@ -115,6 +115,16 @@ docs-%:
 man:
 	./build/gen-man.sh man
 
+######################################################
+#
+# Linux distro package targets
+#
+######################################################
+
+.PHONY: deb
+deb:
+	VERSION=$(VERSION) ./build/gen-deb.sh
+
 ######################################################
 #
 # Wasm targets

build/build-release.sh

@@ -46,6 +46,7 @@ build_release() {
     GOOS=linux GOARCH=amd64 make build
     GOOS=windows GOARCH=amd64 make build
     mv opa_windows_amd64 opa_windows_amd64.exe
+    build_distro_packages
     mv opa_*_* $OUTPUT_DIR
 }
 
@@ -57,6 +58,17 @@ clone_repo() {
     fi
 }
 
+build_distro_packages() {
+    if [ -f build/gen-deb.sh ]; then
+        make man
+        # If VERSION is not set, set it to `make version`
+        VERSION=${VERSION:-`make version`} make deb
+        mv opa_*.* $OUTPUT_DIR
+    else
+        echo "Skip building distro packages. Could not find gen-deb.sh."
+    fi
+}
+
 main() {
     clone_repo
     build_release

build/gen-deb.sh

@@ -0,0 +1,63 @@
+set -e
+
+if [ ! -f "opa_linux_amd64" ]; then
+  echo "ERROR: File 'opa_linux_amd64' not found. First build it 'make build-linux'."
+  exit 1
+fi
+
+if [ ! -d "man" ]; then
+  echo "ERROR: The man pages not found. First build them 'make man'."
+  exit 1
+fi
+
+if [ -z "$VERSION" ]; then
+  echo "ERROR: Need to have VERSION environment variable set."
+  exit 1
+fi
+
+if ! command -v dpkg-deb >/dev/null 2>/dev/null; then
+  echo "ERROR: 'dpkg-deb' was not found and is required."
+  exit 1
+fi
+
+rm -rf tmp_working_dir_opa
+mkdir tmp_working_dir_opa
+cd tmp_working_dir_opa
+
+mkdir -p ./usr/bin/
+cp ../opa_linux_amd64 ./usr/bin/opa
+chmod +x ./usr/bin/opa
+
+mkdir -p ./usr/share/man/man1/
+for MAN_PAGE in ../man/*.1; do
+  gzip --keep --best $MAN_PAGE
+done
+mv ../man/*.1.gz ./usr/share/man/man1/
+
+echo "Package: opa" > control
+echo "Version: $VERSION" >> control
+cat << 'EOF' >> control
+Architecture: amd64
+Maintainer: OPA Maintainers <cncf-opa-maintainers@lists.cncf.io>
+Depends: libc6 (>= 2.2.5)
+Section: admin
+Priority: optional
+Homepage: https://openpolicyagent.org
+Description: An open source, general-purpose policy engine.
+ The Open Policy Agent (OPA) is an open source, general-purpose
+ policy engine that enables unified, context-aware policy
+ enforcement across the entire stack.
+EOF
+
+md5sum ../opa_linux_amd64 > md5sums
+
+mkdir -p opa_$VERSION/DEBIAN
+mv control opa_$VERSION/DEBIAN/control
+mv md5sums opa_$VERSION/DEBIAN/md5sums
+mv ./usr opa_$VERSION/usr
+
+dpkg-deb -b opa_$VERSION/
+
+mv opa_$VERSION.deb ../
+cd ..
+rm -rf tmp_working_dir_opa