Add MySQL database backup support

Dump MySQL/MariaDB databases as part of backup snapshots. Each database
is dumped to a separate gzipped file under _mysql/ in the snapshot.
Supports all-databases mode with exclude list, or explicit database
selection. Includes TUI form fields for full configuration.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

bin/gniza

@@ -15,6 +15,7 @@ source "$GNIZA_DIR/lib/locking.sh"
 source "$GNIZA_DIR/lib/targets.sh"
 source "$GNIZA_DIR/lib/remotes.sh"
 source "$GNIZA_DIR/lib/backup.sh"
+source "$GNIZA_DIR/lib/mysql.sh"
 source "$GNIZA_DIR/lib/restore.sh"
 source "$GNIZA_DIR/lib/retention.sh"
 source "$GNIZA_DIR/lib/schedule.sh"
@@ -206,6 +207,15 @@ run_cli() {
                     echo "TARGET_PRE_HOOK=$TARGET_PRE_HOOK"
                     echo "TARGET_POST_HOOK=$TARGET_POST_HOOK"
                     echo "TARGET_ENABLED=$TARGET_ENABLED"
+                    echo "TARGET_MYSQL_ENABLED=$TARGET_MYSQL_ENABLED"
+                    echo "TARGET_MYSQL_MODE=$TARGET_MYSQL_MODE"
+                    echo "TARGET_MYSQL_DATABASES=$TARGET_MYSQL_DATABASES"
+                    echo "TARGET_MYSQL_EXCLUDE=$TARGET_MYSQL_EXCLUDE"
+                    echo "TARGET_MYSQL_USER=$TARGET_MYSQL_USER"
+                    echo "TARGET_MYSQL_PASSWORD=****"
+                    echo "TARGET_MYSQL_HOST=$TARGET_MYSQL_HOST"
+                    echo "TARGET_MYSQL_PORT=$TARGET_MYSQL_PORT"
+                    echo "TARGET_MYSQL_EXTRA_OPTS=$TARGET_MYSQL_EXTRA_OPTS"
                     ;;
                 *)
                     die "Unknown targets action: $action (expected list|add|delete|show)"

etc/target.conf.example

@@ -9,3 +9,13 @@ TARGET_RETENTION=""
 TARGET_PRE_HOOK=""
 TARGET_POST_HOOK=""
 TARGET_ENABLED="yes"
+# MySQL Backup
+#TARGET_MYSQL_ENABLED="no"
+#TARGET_MYSQL_MODE="all"
+#TARGET_MYSQL_DATABASES=""
+#TARGET_MYSQL_EXCLUDE=""
+#TARGET_MYSQL_USER=""
+#TARGET_MYSQL_PASSWORD=""
+#TARGET_MYSQL_HOST="localhost"
+#TARGET_MYSQL_PORT="3306"
+#TARGET_MYSQL_EXTRA_OPTS="--single-transaction --routines --triggers"

lib/backup.sh

@@ -101,6 +101,19 @@ _backup_target_impl() {
         fi
     fi
 
+    # 8.5. Dump MySQL databases (if enabled)
+    local mysql_dump_dir=""
+    if [[ "${TARGET_MYSQL_ENABLED:-no}" == "yes" ]]; then
+        log_info "Dumping MySQL databases for $target_name..."
+        if mysql_dump_databases; then
+            mysql_dump_dir="${MYSQL_DUMP_DIR:-}"
+        else
+            log_error "MySQL dump failed for $target_name"
+            mysql_cleanup_dump
+            return 1
+        fi
+    fi
+
     # 9. Transfer each folder
     local folder
     local transfer_failed=false
@@ -112,6 +125,18 @@ _backup_target_impl() {
         fi
     done < <(get_target_folders)
 
+    # 9.5. Transfer MySQL dumps
+    if [[ -n "$mysql_dump_dir" && -d "$mysql_dump_dir/_mysql" ]]; then
+        log_info "Transferring MySQL dumps for $target_name..."
+        if ! transfer_folder "$target_name" "$mysql_dump_dir/_mysql" "$ts" "$prev"; then
+            log_error "Transfer failed for MySQL dumps"
+            transfer_failed=true
+        fi
+    fi
+
+    # Cleanup MySQL temp dir
+    mysql_cleanup_dump
+
     if [[ "$transfer_failed" == "true" ]]; then
         log_error "One or more folder transfers failed for $target_name"
         return 1
@@ -132,6 +157,7 @@ _backup_target_impl() {
   "timestamp": "$ts",
   "duration": $duration,
   "folders": "$(echo "$TARGET_FOLDERS" | sed 's/"/\\"/g')",
+  "mysql_dumps": $([ "${TARGET_MYSQL_ENABLED:-no}" = "yes" ] && echo "true" || echo "false"),
   "total_size": $total_size,
   "mode": "${BACKUP_MODE:-$DEFAULT_BACKUP_MODE}",
   "pinned": false

lib/mysql.sh

@@ -0,0 +1,201 @@
+#!/usr/bin/env bash
+# gniza4linux/lib/mysql.sh — MySQL database dump support
+
+[[ -n "${_GNIZA4LINUX_MYSQL_LOADED:-}" ]] && return 0
+_GNIZA4LINUX_MYSQL_LOADED=1
+
+# System databases always excluded from dumps
+_MYSQL_SYSTEM_DBS="information_schema performance_schema sys"
+
+# Detect the mysqldump binary (MySQL or MariaDB).
+_mysql_find_dump_cmd() {
+    if command -v mysqldump &>/dev/null; then
+        echo "mysqldump"
+    elif command -v mariadb-dump &>/dev/null; then
+        echo "mariadb-dump"
+    else
+        return 1
+    fi
+}
+
+# Detect the mysql client binary.
+_mysql_find_client_cmd() {
+    if command -v mysql &>/dev/null; then
+        echo "mysql"
+    elif command -v mariadb &>/dev/null; then
+        echo "mariadb"
+    else
+        return 1
+    fi
+}
+
+# Build connection arguments from TARGET_MYSQL_* globals into MYSQL_CONN_ARGS array.
+# Sets MYSQL_PWD env var if password is configured.
+mysql_build_conn_args() {
+    MYSQL_CONN_ARGS=()
+    if [[ -n "${TARGET_MYSQL_USER:-}" ]]; then
+        MYSQL_CONN_ARGS+=(-u "$TARGET_MYSQL_USER")
+    fi
+    if [[ -n "${TARGET_MYSQL_HOST:-}" && "${TARGET_MYSQL_HOST}" != "localhost" ]]; then
+        MYSQL_CONN_ARGS+=(-h "$TARGET_MYSQL_HOST")
+    fi
+    if [[ -n "${TARGET_MYSQL_PORT:-}" && "${TARGET_MYSQL_PORT}" != "3306" ]]; then
+        MYSQL_CONN_ARGS+=(-P "$TARGET_MYSQL_PORT")
+    fi
+    if [[ -n "${TARGET_MYSQL_PASSWORD:-}" ]]; then
+        export MYSQL_PWD="${TARGET_MYSQL_PASSWORD}"
+    fi
+}
+
+# Get list of databases to dump.
+# Outputs one database name per line.
+mysql_get_databases() {
+    local client_cmd
+    client_cmd=$(_mysql_find_client_cmd) || {
+        log_error "MySQL/MariaDB client not found"
+        return 1
+    }
+
+    mysql_build_conn_args
+
+    local all_dbs
+    all_dbs=$("$client_cmd" "${MYSQL_CONN_ARGS[@]}" -N -e "SHOW DATABASES" 2>&1) || {
+        log_error "Failed to list databases: $all_dbs"
+        return 1
+    }
+
+    # Build exclude list: system dbs + user-specified excludes
+    local -a exclude_list=()
+    local db
+    for db in $_MYSQL_SYSTEM_DBS; do
+        exclude_list+=("$db")
+    done
+    if [[ -n "${TARGET_MYSQL_EXCLUDE:-}" ]]; then
+        local -a user_excludes
+        IFS=',' read -ra user_excludes <<< "$TARGET_MYSQL_EXCLUDE"
+        local ex
+        for ex in "${user_excludes[@]}"; do
+            ex="${ex#"${ex%%[![:space:]]*}"}"
+            ex="${ex%"${ex##*[![:space:]]}"}"
+            [[ -n "$ex" ]] && exclude_list+=("$ex")
+        done
+    fi
+
+    while IFS= read -r db; do
+        db="${db#"${db%%[![:space:]]*}"}"
+        db="${db%"${db##*[![:space:]]}"}"
+        [[ -z "$db" ]] && continue
+
+        # Skip system/excluded databases
+        local skip=false
+        local ex
+        for ex in "${exclude_list[@]}"; do
+            if [[ "$db" == "$ex" ]]; then
+                skip=true
+                break
+            fi
+        done
+        [[ "$skip" == "true" ]] && continue
+
+        echo "$db"
+    done <<< "$all_dbs"
+}
+
+# Dump all configured databases to a temp directory.
+# Sets MYSQL_DUMP_DIR global to the temp directory path containing _mysql/ subdir.
+# Returns 0 on success, 1 on failure.
+mysql_dump_databases() {
+    local dump_cmd
+    dump_cmd=$(_mysql_find_dump_cmd) || {
+        log_error "mysqldump/mariadb-dump not found — cannot dump MySQL databases"
+        return 1
+    }
+
+    mysql_build_conn_args
+
+    # Determine databases to dump
+    local -a databases=()
+    if [[ "${TARGET_MYSQL_MODE:-all}" == "select" ]]; then
+        # Use explicitly listed databases
+        if [[ -z "${TARGET_MYSQL_DATABASES:-}" ]]; then
+            log_error "MySQL mode=select but TARGET_MYSQL_DATABASES is empty"
+            return 1
+        fi
+        local -a db_list
+        IFS=',' read -ra db_list <<< "$TARGET_MYSQL_DATABASES"
+        local db
+        for db in "${db_list[@]}"; do
+            db="${db#"${db%%[![:space:]]*}"}"
+            db="${db%"${db##*[![:space:]]}"}"
+            [[ -n "$db" ]] && databases+=("$db")
+        done
+    else
+        # mode=all: discover databases, apply excludes
+        local db_output
+        db_output=$(mysql_get_databases) || {
+            log_error "Failed to discover MySQL databases"
+            return 1
+        }
+        while IFS= read -r db; do
+            [[ -n "$db" ]] && databases+=("$db")
+        done <<< "$db_output"
+    fi
+
+    if [[ ${#databases[@]} -eq 0 ]]; then
+        log_warn "No databases to dump"
+        return 0
+    fi
+
+    # Create temp directory
+    MYSQL_DUMP_DIR=$(mktemp -d "${TMPDIR:-/tmp}/gniza-mysql-XXXXXX")
+    mkdir -p "$MYSQL_DUMP_DIR/_mysql"
+
+    # Parse extra opts into array
+    local -a extra_opts_arr=()
+    if [[ -n "${TARGET_MYSQL_EXTRA_OPTS:-}" ]]; then
+        read -ra extra_opts_arr <<< "${TARGET_MYSQL_EXTRA_OPTS}"
+    else
+        extra_opts_arr=(--single-transaction --routines --triggers)
+    fi
+    local failed=false
+
+    for db in "${databases[@]}"; do
+        # Validate database name to prevent path traversal
+        if [[ ! "$db" =~ ^[a-zA-Z0-9_-]+$ ]]; then
+            log_error "Invalid database name, skipping: $db"
+            failed=true
+            continue
+        fi
+        log_info "Dumping MySQL database: $db"
+        local outfile="$MYSQL_DUMP_DIR/_mysql/${db}.sql.gz"
+        local errfile="$MYSQL_DUMP_DIR/_mysql/${db}.err"
+        if "$dump_cmd" "${MYSQL_CONN_ARGS[@]}" "${extra_opts_arr[@]}" "$db" 2>"$errfile" | gzip > "$outfile"; then
+            rm -f "$errfile"
+            local size; size=$(stat -c%s "$outfile" 2>/dev/null || echo "?")
+            log_debug "Dumped $db -> ${db}.sql.gz ($size bytes)"
+        else
+            log_error "Failed to dump database: $db"
+            [[ -s "$errfile" ]] && log_error "mysqldump: $(cat "$errfile")"
+            rm -f "$errfile"
+            failed=true
+        fi
+    done
+
+    if [[ "$failed" == "true" ]]; then
+        log_error "One or more MySQL dumps failed"
+        return 1
+    fi
+
+    log_info "MySQL dumps completed: ${#databases[@]} database(s) in $MYSQL_DUMP_DIR/_mysql/"
+    return 0
+}
+
+# Clean up the temporary MySQL dump directory and env vars.
+mysql_cleanup_dump() {
+    if [[ -n "${MYSQL_DUMP_DIR:-}" && -d "$MYSQL_DUMP_DIR" ]]; then
+        rm -rf "$MYSQL_DUMP_DIR"
+        log_debug "Cleaned up MySQL dump dir: $MYSQL_DUMP_DIR"
+        MYSQL_DUMP_DIR=""
+    fi
+    unset MYSQL_PWD 2>/dev/null || true
+}

lib/targets.sh

@@ -53,6 +53,15 @@ load_target() {
     TARGET_PRE_HOOK="${TARGET_PRE_HOOK:-}"
     TARGET_POST_HOOK="${TARGET_POST_HOOK:-}"
     TARGET_ENABLED="${TARGET_ENABLED:-yes}"
+    TARGET_MYSQL_ENABLED="${TARGET_MYSQL_ENABLED:-no}"
+    TARGET_MYSQL_MODE="${TARGET_MYSQL_MODE:-all}"
+    TARGET_MYSQL_DATABASES="${TARGET_MYSQL_DATABASES:-}"
+    TARGET_MYSQL_EXCLUDE="${TARGET_MYSQL_EXCLUDE:-}"
+    TARGET_MYSQL_USER="${TARGET_MYSQL_USER:-}"
+    TARGET_MYSQL_PASSWORD="${TARGET_MYSQL_PASSWORD:-}"
+    TARGET_MYSQL_HOST="${TARGET_MYSQL_HOST:-localhost}"
+    TARGET_MYSQL_PORT="${TARGET_MYSQL_PORT:-3306}"
+    TARGET_MYSQL_EXTRA_OPTS="${TARGET_MYSQL_EXTRA_OPTS:---single-transaction --routines --triggers}"
 
     log_debug "Loaded target '$name': folders=${TARGET_FOLDERS} enabled=${TARGET_ENABLED}"
 }
@@ -72,10 +81,10 @@ validate_target() {
         ((errors++)) || true
     fi
 
-    if [[ -z "$TARGET_FOLDERS" ]]; then
+    if [[ -z "$TARGET_FOLDERS" && "${TARGET_MYSQL_ENABLED:-no}" != "yes" ]]; then
-        log_error "Target '$name': TARGET_FOLDERS is required"
+        log_error "Target '$name': TARGET_FOLDERS is required (or enable MySQL backup)"
         ((errors++)) || true
-    else
+    elif [[ -n "$TARGET_FOLDERS" ]]; then
         # Validate each folder exists
         local -a folders
         IFS=',' read -ra folders <<< "$TARGET_FOLDERS"

tui/gniza.tcss

@@ -235,3 +235,9 @@ Select {
 Switch {
     margin: 0 1;
 }
+
+.section-label {
+    text-style: bold;
+    color: #00cc00;
+    margin: 1 0 0 0;
+}

tui/models.py

@@ -11,6 +11,15 @@ class Target:
     pre_hook: str = ""
     post_hook: str = ""
     enabled: str = "yes"
+    mysql_enabled: str = "no"
+    mysql_mode: str = "all"
+    mysql_databases: str = ""
+    mysql_exclude: str = ""
+    mysql_user: str = ""
+    mysql_password: str = ""
+    mysql_host: str = "localhost"
+    mysql_port: str = "3306"
+    mysql_extra_opts: str = "--single-transaction --routines --triggers"
 
     def to_conf(self) -> dict[str, str]:
         return {
@@ -22,6 +31,15 @@ class Target:
             "TARGET_PRE_HOOK": self.pre_hook,
             "TARGET_POST_HOOK": self.post_hook,
             "TARGET_ENABLED": self.enabled,
+            "TARGET_MYSQL_ENABLED": self.mysql_enabled,
+            "TARGET_MYSQL_MODE": self.mysql_mode,
+            "TARGET_MYSQL_DATABASES": self.mysql_databases,
+            "TARGET_MYSQL_EXCLUDE": self.mysql_exclude,
+            "TARGET_MYSQL_USER": self.mysql_user,
+            "TARGET_MYSQL_PASSWORD": self.mysql_password,
+            "TARGET_MYSQL_HOST": self.mysql_host,
+            "TARGET_MYSQL_PORT": self.mysql_port,
+            "TARGET_MYSQL_EXTRA_OPTS": self.mysql_extra_opts,
         }
 
     @classmethod
@@ -35,6 +53,15 @@ class Target:
             pre_hook=data.get("TARGET_PRE_HOOK", ""),
             post_hook=data.get("TARGET_POST_HOOK", ""),
             enabled=data.get("TARGET_ENABLED", "yes"),
+            mysql_enabled=data.get("TARGET_MYSQL_ENABLED", "no"),
+            mysql_mode=data.get("TARGET_MYSQL_MODE", "all"),
+            mysql_databases=data.get("TARGET_MYSQL_DATABASES", ""),
+            mysql_exclude=data.get("TARGET_MYSQL_EXCLUDE", ""),
+            mysql_user=data.get("TARGET_MYSQL_USER", ""),
+            mysql_password=data.get("TARGET_MYSQL_PASSWORD", ""),
+            mysql_host=data.get("TARGET_MYSQL_HOST", "localhost"),
+            mysql_port=data.get("TARGET_MYSQL_PORT", "3306"),
+            mysql_extra_opts=data.get("TARGET_MYSQL_EXTRA_OPTS", "--single-transaction --routines --triggers"),
         )
 
 

tui/screens/target_edit.py

@@ -52,6 +52,33 @@ class TargetEditScreen(Screen):
                 value="yes" if target.enabled == "yes" else "no",
                 id="te-enabled",
             )
+            yield Static("--- MySQL Backup ---", classes="section-label")
+            yield Static("MySQL Enabled:")
+            yield Select(
+                [("No", "no"), ("Yes", "yes")],
+                value=target.mysql_enabled,
+                id="te-mysql-enabled",
+            )
+            yield Static("MySQL Mode:")
+            yield Select(
+                [("All databases", "all"), ("Select databases", "select")],
+                value=target.mysql_mode,
+                id="te-mysql-mode",
+            )
+            yield Static("Databases (comma-separated, when mode=select):")
+            yield Input(value=target.mysql_databases, placeholder="db1,db2", id="te-mysql-databases")
+            yield Static("Exclude databases (comma-separated, when mode=all):")
+            yield Input(value=target.mysql_exclude, placeholder="test_db,dev_db", id="te-mysql-exclude")
+            yield Static("MySQL User:")
+            yield Input(value=target.mysql_user, placeholder="Leave empty for socket/~/.my.cnf auth", id="te-mysql-user")
+            yield Static("MySQL Password:")
+            yield Input(value=target.mysql_password, placeholder="Leave empty for socket/~/.my.cnf auth", password=True, id="te-mysql-password")
+            yield Static("MySQL Host:")
+            yield Input(value=target.mysql_host, placeholder="localhost", id="te-mysql-host")
+            yield Static("MySQL Port:")
+            yield Input(value=target.mysql_port, placeholder="3306", id="te-mysql-port")
+            yield Static("MySQL Extra Options:")
+            yield Input(value=target.mysql_extra_opts, placeholder="--single-transaction --routines --triggers", id="te-mysql-extra-opts")
             with Horizontal(id="te-buttons"):
                 yield Button("Save", variant="primary", id="btn-save")
                 yield Button("Cancel", id="btn-cancel")
@@ -96,8 +123,9 @@ class TargetEditScreen(Screen):
             name = self._edit_name
 
         folders = self.query_one("#te-folders", Input).value.strip()
-        if not folders:
+        mysql_enabled = str(self.query_one("#te-mysql-enabled", Select).value)
-            self.notify("At least one folder is required", severity="error")
+        if not folders and mysql_enabled != "yes":
+            self.notify("At least one folder or MySQL backup is required", severity="error")
             return
 
         target = Target(
@@ -109,6 +137,15 @@ class TargetEditScreen(Screen):
             pre_hook=self.query_one("#te-prehook", Input).value.strip(),
             post_hook=self.query_one("#te-posthook", Input).value.strip(),
             enabled=str(self.query_one("#te-enabled", Select).value),
+            mysql_enabled=mysql_enabled,
+            mysql_mode=str(self.query_one("#te-mysql-mode", Select).value),
+            mysql_databases=self.query_one("#te-mysql-databases", Input).value.strip(),
+            mysql_exclude=self.query_one("#te-mysql-exclude", Input).value.strip(),
+            mysql_user=self.query_one("#te-mysql-user", Input).value.strip(),
+            mysql_password=self.query_one("#te-mysql-password", Input).value.strip(),
+            mysql_host=self.query_one("#te-mysql-host", Input).value.strip(),
+            mysql_port=self.query_one("#te-mysql-port", Input).value.strip(),
+            mysql_extra_opts=self.query_one("#te-mysql-extra-opts", Input).value.strip(),
         )
         conf = CONFIG_DIR / "targets.d" / f"{name}.conf"
         write_conf(conf, target.to_conf())