From 51d0b817fe0e56a733cd1b445b81321831b0c4f3 Mon Sep 17 00:00:00 2001
From: Evilham <cvs@evilham.com>
Date: Fri, 18 Jun 2021 20:52:58 +0200
Subject: [PATCH] [__single_binary_service] Type to manage very simple
 services.

---
 explorer/explorer-version      |  10 +++
 manifest                       | 158 +++++++++++++++++++++++++++++++++
 parameter/boolean              |   1 +
 parameter/default/service-args |   0
 parameter/default/state        |   1 +
 parameter/default/user         |   1 +
 parameter/optional             |   8 ++
 parameter/optional_multiple    |   1 +
 parameter/required             |   3 +
 9 files changed, 183 insertions(+)
 create mode 100755 explorer/explorer-version
 create mode 100755 manifest
 create mode 100644 parameter/boolean
 create mode 100644 parameter/default/service-args
 create mode 100644 parameter/default/state
 create mode 100644 parameter/default/user
 create mode 100644 parameter/optional
 create mode 100644 parameter/optional_multiple
 create mode 100644 parameter/required

diff --git a/explorer/explorer-version b/explorer/explorer-version
new file mode 100755
index 0000000..690cc5f
--- /dev/null
+++ b/explorer/explorer-version
@@ -0,0 +1,10 @@
+#!/bin/sh -e
+
+BIN_PREFIX="/usr/local/bin"
+SERVICE_NAME="${__object_id}"
+
+VERSION_FILE="${BIN_PREFIX}/.${SERVICE_NAME}.cdist.version"
+
+if [ -f "${VERSION_FILE}" ]; then
+	cat "${VERSION_FILE}"
+fi
diff --git a/manifest b/manifest
new file mode 100755
index 0000000..d5df410
--- /dev/null
+++ b/manifest
@@ -0,0 +1,158 @@
+#!/bin/sh -e
+
+BIN_DIR="/usr/local/bin"
+
+# Ensure the target bin dir exists
+__directory "${BIN_DIR}" \
+	--mode 0755
+export require="${require} __directory${BIN_DIR}"
+
+STATE="$(cat "${__object}/parameter/state")"
+USER="$(cat "${__object}/parameter/user")"
+GROUP="$(cat "${__object}/parameter/group" 2>/dev/null || true)"
+if [ -z "${GROUP}" ]; then
+	GROUP="${USER}"
+fi
+
+SERVICE_NAME="${__object_id}"
+
+BINARY="$(cat "${__object}/parameter/binary" 2>/dev/null || true)"
+if [ -z "${BINARY}" ]; then
+	BINARY="${SERVICE_NAME}"
+fi
+EXTRA_BINARIES="$(cat "${__object}/parameter/extra-binary" 2>/dev/null || true)"
+# This only makes sense for file archives
+if [ -n "${EXTRA_BINARIES}" ] && [ -f "${__object}/parameter/unpack" ]; then
+	cat >> /dev/stderr <<-EOF
+	You cannot specify extra binaries without the --unpack argument.
+	Make sure that the --url argument points to a file archive.
+EOF
+fi
+
+SERVICE_EXEC="$(cat "${__object}/parameter/service-exec" 2>/dev/null || true)"
+if [ -z "${SERVICE_EXEC}" ]; then
+	SERVICE_EXEC="${BIN_DIR}/${BINARY}"
+fi
+SERVICE_EXEC="${SERVICE_EXEC} $(cat "${__object}/parameter/service-args")"
+
+SERVICE_DESCRIPTION="$(cat "${__object}/parameter/service-description" \
+	2>/dev/null || true)"
+if [ -z "${SERVICE_DESCRIPTION}" ]; then
+	SERVICE_DESCRIPTION="cdist-managed '${SERVICE_NAME}' service"
+fi
+
+DOWNLOAD_URL="$(cat "${__object}/parameter/url")"
+CHECKSUM="$(cat "${__object}/parameter/checksum")"
+SHOULD_VERSION="$(cat "${__object}/parameter/version")"
+
+# Create a user for the service if it is not root
+if [ "${USER}" != "root" ]; then
+	__user "${USER}" \
+		--system \
+		--state "${STATE}" \
+		--home /nonexistent \
+		--comment "cdist-managed ${SERVICE_NAME} user"
+	# Track dependencies
+	service_require="${service_require} __user/${USER}"
+fi
+
+# TODO: Support non-systemd
+__systemd_unit "${SERVICE_NAME}.service" \
+	--source "-" \
+	--state "${STATE}" \
+	--enablement-state "enabled" <<EOF
+[Unit]
+Description=${SERVICE_DESCRIPTION}
+After=network.target
+
+[Service]
+Type=simple
+
+User=${USER}
+Group=${GROUP}
+ExecStart=${SERVICE_EXEC}
+Restart=always
+
+[Install]
+WantedBy=multi-user.target
+EOF
+service_require="${service_require} __systemd_unit/${SERVICE_NAME}.service"
+
+# Proceed after user and service description have been prepared
+export require="${require} ${service_require}"
+
+
+VERSION_FILE="${BIN_DIR}/.${SERVICE_NAME}.cdist.version"
+IS_VERSION="$(cat "${__object}/explorer/explorer-version")"
+
+if [ "${SHOULD_VERSION}" != "${IS_VERSION}" ] && \
+		[ "${STATE}" = "present" ]; then
+	# We are installing the service and there has been a version change
+	# (or it is first-time install)
+	TMP_PATH="/tmp/${SERVICE_NAME}-${SHOULD_VERSION}"
+
+	# This is what will stop the service, replace the binaries and
+	# start the service again
+	perform_service_upgrade="$(cat <<EOF
+service ${SERVICE_NAME} stop || true
+for bin_file in ${BINARY} ${EXTRA_BINARIES}; do
+	bin_path="${TMP_PATH}/\${bin_file}"
+	# TODO: on the BSDs, the super user group is wheel
+	chown root:root "\${bin_path}"
+	chmod 0555 "\${bin_path}"
+	cp -af "\${bin_path}" "${BIN_DIR}/\${bin_file}"
+done
+service ${SERVICE_NAME} start || true
+EOF
+)"
+
+	if [ -f "${__object}/parameter/unpack" ]; then
+		# TODO: Support files other than .tar.gz
+		UNPACK_ARGS="$(cat "${__object}/parameter/unpack-args" \
+			2>/dev/null || true)"
+		# Download packed file
+		__download "${TMP_PATH}.tar.gz" \
+			--url "${DOWNLOAD_URL}" \
+			--download remote \
+			--sum "${CHECKSUM}"
+
+		# Unpack file and also perform service upgrade
+		# shellcheck disable=SC2086
+		require="__download${TMP_PATH}.tar.gz" \
+			__unpack "${TMP_PATH}.tar.gz" \
+			${UNPACK_ARGS} \
+			--destination "${TMP_PATH}" \
+			--onchange "$(cat <<EOF
+${perform_service_upgrade}
+EOF
+)"
+		version_bump_require="__unpack${TMP_PATH}.tar.gz"
+	else
+		# Create temp directory
+		__directory "${TMP_PATH}"
+		# Download binary directoy to the temp directory with the
+		# specified binary name
+		# And also perform service upgrade
+		require="__directory${TMP_PATH}" __download \
+			"${TMP_PATH}/${BINARY}" \
+			--url "${DOWNLOAD_URL}" \
+			--download remote \
+			--sum "${CHECKSUM}" \
+			--onchange "${perform_service_upgrade}"
+		version_bump_require="__download${TMP_PATH}/${BINARY}"
+	fi
+
+	# Perform update of cdist-managed version file
+	# only after binaries have been upgraded
+	printf "%s" "${SHOULD_VERSION}" | \
+		require="${version_bump_require}" __file \
+			"${VERSION_FILE}" \
+			--source "-"
+fi
+if [ "${STATE}" = "absent" ]; then
+	# Perform cleanup of generated files
+	for bin_file in ${BINARY} ${EXTRA_BINARIES}; do
+		__file "${BINARY_PREFIX}/${bin_file}" --state "absent"
+	done
+	__file "${VERSION_FILE}" --state "absent"
+fi
diff --git a/parameter/boolean b/parameter/boolean
new file mode 100644
index 0000000..f5f0902
--- /dev/null
+++ b/parameter/boolean
@@ -0,0 +1 @@
+unpack
diff --git a/parameter/default/service-args b/parameter/default/service-args
new file mode 100644
index 0000000..e69de29
diff --git a/parameter/default/state b/parameter/default/state
new file mode 100644
index 0000000..e7f6134
--- /dev/null
+++ b/parameter/default/state
@@ -0,0 +1 @@
+present
diff --git a/parameter/default/user b/parameter/default/user
new file mode 100644
index 0000000..d8649da
--- /dev/null
+++ b/parameter/default/user
@@ -0,0 +1 @@
+root
diff --git a/parameter/optional b/parameter/optional
new file mode 100644
index 0000000..6751e9c
--- /dev/null
+++ b/parameter/optional
@@ -0,0 +1,8 @@
+user
+group
+state
+binary
+service-args
+service-exec
+service-description
+unpack-args
diff --git a/parameter/optional_multiple b/parameter/optional_multiple
new file mode 100644
index 0000000..e1ca562
--- /dev/null
+++ b/parameter/optional_multiple
@@ -0,0 +1 @@
+extra-binary
diff --git a/parameter/required b/parameter/required
new file mode 100644
index 0000000..b1e8d01
--- /dev/null
+++ b/parameter/required
@@ -0,0 +1,3 @@
+url
+checksum
+version