pg_snap

#!/bin/bash

# Default values
PARENT_DIR=$(dirname $PWD)
DB_NAME=$(basename $PARENT_DIR)
SNAPSHOT_DIR=/tmp/pg_snap/snapshots
processor_cores=$(sysctl -n hw.ncpu)

CURRENT_VERSION="1.0.1"
GITHUB_URL="https://raw.githubusercontent.com/iseth/pg-snap/master/pg_snap"

check_for_update() {
    echo "Checking for updates..."
    # Fetch the latest version number from GitHub (this assumes the GitHub version also contains a CURRENT_VERSION declaration)
    LATEST_VERSION=$(curl -s $GITHUB_URL | grep "^CURRENT_VERSION=" | cut -d\" -f2)

    # Compare version numbers, if the latest version is not the current version, update
    if [ "$LATEST_VERSION" != "$CURRENT_VERSION" ]; then
        echo "Update available. Updating..."
        curl -s $GITHUB_URL -o $0 # $0 refers to the current script's name. This command will replace the current script with the updated version.
        echo "Script updated to version $LATEST_VERSION. Please run it again to use the updated version."
        exit
    else
        echo "You are using the latest version."
    fi
}

list_snapshots () {
    mkdir -p $SNAPSHOT_DIR
    files=$(find $SNAPSHOT_DIR -type f -name "$DB_NAME*" -exec basename {} \;)

    declare -a files_array=($(find $SNAPSHOT_DIR -type f -name "$DB_NAME*" -exec basename {} \;))

    # Sort the array
    IFS=$'\n' sorted_array=($(sort <<<"${files_array[*]}"))

    # Print the sorted array (optional, for verification)
    for file in "${sorted_array[@]}"; do
        echo $file
    done
    # find $SNAPSHOT_DIR -maxdepth 1 -type f -name "$DB_name*" -exec basename {} \;
}

create_snapshot () {
    mkdir -p $SNAPSHOT_DIR
    output=$(pg_dump -U postgres -h localhost -p 5432 -F c -b -v -f /dev/null $DB_NAME 2>&1)
    filename=$DB_NAME--"$(date '+%Y-%m-%d-%H:%M:%S')".backup

    if [ $? -eq 0 ]; then
        pg_dump -U postgres -h localhost -p 5432 -F c -b -f $SNAPSHOT_DIR/$filename $DB_NAME
        echo "Snapshot: $filename"
        echo "Backup successful!"
    else
        echo "Backup failed. See error below:"
        echo "$output"
        exit 1
    fi
}

restore_snapshot() {
    latest_snapshot=$(list_snapshots | tail -1)
    selected_snapshot=${1:-$latest_snapshot}

    drop_database
    create_database

    output=$(pg_restore --verbose --no-acl --no-owner -U postgres -h localhost -p 5432 -d $DB_NAME $SNAPSHOT_DIR/$selected_snapshot --jobs=$processor_cores 2>&1)

    if [ $? -eq 0 ]; then
        echo "Snapshot: $selected_snapshot"
        echo "Restore successful!"
    else
        echo "Backup failed. See error below:"
        echo "$output"
        exit 1
    fi
}

delete_snapshot() {
    latest_snapshot=$(list_snapshots | tail -1)
    selected_snapshot=${1:-$latest_snapshot}

    echo "Delete snapshot: $selected_snapshot"
    rm $SNAPSHOT_DIR/$selected_snapshot
}

# drop database
drop_database () {
    output=$(dropdb -e -f -U postgres $DB_NAME 2>&1)

    if [ $? -eq 0 ]; then
        echo "Database $DB_NAME successfully dropped."
    else
        echo "Failed to drop the database $DB_NAME."
    fi
}

create_database () {
    output=$(createdb -e -U postgres $DB_NAME 2>&1)

    if [ $? -eq 0 ]; then
        echo "Database $DB_NAME successfully created."
    else
        echo "Failed to create the database $DB_NAME."
    fi
}

set_db () {
    DB_NAME=$1
}

get_timestamp () {
    my_string=$1

    # Use parameter expansion to split string by "--"
    part1=()

    while [[ $my_string =~ "--" ]]; do
        part1+=("${my_string%%--*}")
        my_string="${my_string#*--}"
    done

    # echo "Array: ${part1[@]}"
    # echo "String: $my_string"
    part1+=("$my_string")

    IFS='.' read -ra part2 <<< "$my_string"
    echo ${part2[0]}
}

check_for_update
while [[ "$#" -gt 0 ]]; do
    case $1 in
        -l|--list) list_snapshots "$2"; shift ;;
        -c|--create) create_snapshot "$2"; shift;;
        -r|--restore) restore_snapshot "$2"; shift;;
        -db|--db-name) set_db "$2"; shift;;
        -v|--version) echo "Script version: $VERSION"; exit 0 ;;
        *) echo "Unknown parameter passed: $1"; exit 1 ;;
    esac
    shift
done

echo ""

#dropdb -e -f -U postgres $1