dropshell/templates/watchtower/_common.sh

#!/bin/bash

# COMMON FUNCTIONS
# JDE
# 2025-04-25

# This file is not required if you write your own template.


# Print error message and exit with code 1
# Usage: die "error message"
die() {
    echo -e "\033[91mError: $1\033[0m"
    exit 1
}

# Load environment variables from .env file
# Usage: load_env [path_to_env_file]
# If no path is provided, looks for .env in the same directory as the script
load_env() {
    local script_dir="$(dirname "${BASH_SOURCE[0]}")"
    local env_file

    # first load basic.env for the template defaults
    if [ -f "$script_dir/_basic.env" ]; then
        set -a
        source "$script_dir/_basic.env"
        set +a
    else
        echo "Warning: _basic.env file not found at $script_dir/_basic.env. Broken template?"
        return 1
    fi

    # now load the server specific env file
    if [ -z "$1" ]; then
        echo "Usage: $0 [path_to_env_file]"
        return 1
    fi

    env_file="$1/service.env"    

    if [ ! -f "$env_file" ]; then
        echo "Warning: service.env file not found at $1"
        return 1
    fi

    set -a
    source "$env_file"
    set +a
}

grey_start() {
    echo -e -n "\033[90m"
}

grey_end() {
    echo -e -n "\033[0m"
}

create_and_start_container() {
    if [ -z "$1" ] || [ -z "$2" ]; then
        die "Template error: create_and_start_container <run_cmd> <container_name>"
    fi

    local run_cmd="$1"
    local container_name="$2"

    if _is_container_exists $container_name; then
        _is_container_running $container_name && return 0
        _start_container $container_name
    else
        grey_start
        $run_cmd
        grey_end
    fi

    if ! _is_container_running $container_name; then
        die "Container ${container_name} failed to start"
    fi

    ID=$(_get_container_id $container_name)
    echo "Container ${container_name} is running with ID ${ID}"
}

function create_folder() {
    local folder="$1"
    if [ -d "$folder" ]; then
        return 0
    fi
    if ! mkdir -p "$folder"; then
        die "Failed to create folder: $folder"
    fi
    chmod 777 "$folder"
    echo "Folder created: $folder"
}

# Check if docker is installed
_check_docker_installed() {
    if ! command -v docker &> /dev/null; then
        echo "Docker is not installed"
        return 1
    fi

    # check if docker daemon is running
    if ! docker info &> /dev/null; then
        echo "Docker daemon is not running"
        return 1
    fi

    # check if user has permission to run docker
    if ! docker run --rm hello-world &> /dev/null; then
        echo "User does not have permission to run docker"
        return 1
    fi

    return 0
}

# Check if a container exists
_is_container_exists() {
    if ! docker ps -a --format "{{.Names}}" | grep -q "^$1$"; then
        return 1
    fi
    return 0
}

# Check if a container is running
_is_container_running() {
    if ! docker ps --format "{{.Names}}" | grep -q "^$1$"; then
        return 1
    fi
    return 0
}

# get contianer ID
_get_container_id() {
    docker ps --format "{{.ID}}" --filter "name=$1"
}

# get container status
_get_container_status() {
    docker ps --format "{{.Status}}" --filter "name=$1"
}

# start container that exists
_start_container() {
    _is_container_exists $1 || return 1
    _is_container_running $1 && return 0
    docker start $1
}

# stop container that exists
_stop_container() {
    _is_container_running $1 || return 0;
    docker stop $1
}   

# remove container that exists
_remove_container() {
    _stop_container $1
    _is_container_exists $1 || return 0;
    docker rm $1
}

# get container logs
_get_container_logs() {
    if ! _is_container_exists $1; then
        echo "Container $1 does not exist"
        return 1
    fi

    docker logs $1
}

check_required_env_vars() {
    local required_vars=("$@")
    for var in "${required_vars[@]}"; do
        if [ -z "${!var}" ]; then
            die "Required environment variable $var is not set in your service.env file"
        fi
    done
}