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prebuildfs/opt/bitnami/scripts/libpersistence.sh

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+#!/bin/bash
+# Copyright Broadcom, Inc. All Rights Reserved.
+# SPDX-License-Identifier: APACHE-2.0
+#
+# Bitnami persistence library
+# Used for bringing persistence capabilities to applications that don't have clear separation of data and logic
+
+# shellcheck disable=SC1091
+
+# Load Generic Libraries
+. /opt/bitnami/scripts/libfs.sh
+. /opt/bitnami/scripts/libos.sh
+. /opt/bitnami/scripts/liblog.sh
+. /opt/bitnami/scripts/libversion.sh
+
+# Functions
+
+########################
+# Persist an application directory
+# Globals:
+#   BITNAMI_ROOT_DIR
+#   BITNAMI_VOLUME_DIR
+# Arguments:
+#   $1 - App folder name
+#   $2 - List of app files to persist
+# Returns:
+#   true if all steps succeeded, false otherwise
+#########################
+persist_app() {
+    local -r app="${1:?missing app}"
+    local -a files_to_restore
+    read -r -a files_to_persist <<< "$(tr ',;:' ' ' <<< "$2")"
+    local -r install_dir="${BITNAMI_ROOT_DIR}/${app}"
+    local -r persist_dir="${BITNAMI_VOLUME_DIR}/${app}"
+    # Persist the individual files
+    if [[ "${#files_to_persist[@]}" -le 0 ]]; then
+        warn "No files are configured to be persisted"
+        return
+    fi
+    pushd "$install_dir" >/dev/null || exit
+    local file_to_persist_relative file_to_persist_destination file_to_persist_destination_folder
+    local -r tmp_file="/tmp/perms.acl"
+    for file_to_persist in "${files_to_persist[@]}"; do
+        if [[ ! -f "$file_to_persist" && ! -d "$file_to_persist" ]]; then
+            error "Cannot persist '${file_to_persist}' because it does not exist"
+            return 1
+        fi
+        file_to_persist_relative="$(relativize "$file_to_persist" "$install_dir")"
+        file_to_persist_destination="${persist_dir}/${file_to_persist_relative}"
+        file_to_persist_destination_folder="$(dirname "$file_to_persist_destination")"
+        # Get original permissions for existing files, which will be applied later
+        # Exclude the root directory with 'sed', to avoid issues when copying the entirety of it to a volume
+        getfacl -R "$file_to_persist_relative" | sed -E '/# file: (\..+|[^.])/,$!d' > "$tmp_file"
+        # Copy directories to the volume
+        ensure_dir_exists "$file_to_persist_destination_folder"
+        cp -Lr --preserve=links "$file_to_persist_relative" "$file_to_persist_destination_folder"
+        # Restore permissions
+        pushd "$persist_dir" >/dev/null || exit
+        if am_i_root; then
+            setfacl --restore="$tmp_file"
+        else
+            # When running as non-root, don't change ownership
+            setfacl --restore=<(grep -E -v '^# (owner|group):' "$tmp_file")
+        fi
+        popd >/dev/null || exit
+    done
+    popd >/dev/null || exit
+    rm -f "$tmp_file"
+    # Install the persisted files into the installation directory, via symlinks
+    restore_persisted_app "$@"
+}
+
+########################
+# Restore a persisted application directory
+# Globals:
+#   BITNAMI_ROOT_DIR
+#   BITNAMI_VOLUME_DIR
+#   FORCE_MAJOR_UPGRADE
+# Arguments:
+#   $1 - App folder name
+#   $2 - List of app files to restore
+# Returns:
+#   true if all steps succeeded, false otherwise
+#########################
+restore_persisted_app() {
+    local -r app="${1:?missing app}"
+    local -a files_to_restore
+    read -r -a files_to_restore <<< "$(tr ',;:' ' ' <<< "$2")"
+    local -r install_dir="${BITNAMI_ROOT_DIR}/${app}"
+    local -r persist_dir="${BITNAMI_VOLUME_DIR}/${app}"
+    # Restore the individual persisted files
+    if [[ "${#files_to_restore[@]}" -le 0 ]]; then
+        warn "No persisted files are configured to be restored"
+        return
+    fi
+    local file_to_restore_relative file_to_restore_origin file_to_restore_destination
+    for file_to_restore in "${files_to_restore[@]}"; do
+        file_to_restore_relative="$(relativize "$file_to_restore" "$install_dir")"
+        # We use 'realpath --no-symlinks' to ensure that the case of '.' is covered and the directory is removed
+        file_to_restore_origin="$(realpath --no-symlinks "${install_dir}/${file_to_restore_relative}")"
+        file_to_restore_destination="$(realpath --no-symlinks "${persist_dir}/${file_to_restore_relative}")"
+        rm -rf "$file_to_restore_origin"
+        ln -sfn "$file_to_restore_destination" "$file_to_restore_origin"
+    done
+}
+
+########################
+# Check if an application directory was already persisted
+# Globals:
+#   BITNAMI_VOLUME_DIR
+# Arguments:
+#   $1 - App folder name
+# Returns:
+#   true if all steps succeeded, false otherwise
+#########################
+is_app_initialized() {
+    local -r app="${1:?missing app}"
+    local -r persist_dir="${BITNAMI_VOLUME_DIR}/${app}"
+    if ! is_mounted_dir_empty "$persist_dir"; then
+        true
+    else
+        false
+    fi
+}