semcon

#!/bin/bash

# resources
# - https://sap1ens.com/blog/2017/07/01/bash-scripting-best-practices/

set -o errexit
set -o pipefail

# helper functions ================

version_info()
{
    echo "semcon, version 0.1"
    echo ""
}

usage_info()
{
    echo "Usage: $0"
    echo -e "\t--help               print this help message"
    echo -e "\t--version            version information"
    echo -e "\t-v|--verbose         print additional information"
    echo ""
    echo -e "\tstart <file.yaml>    start a Semantic Container with configuration in"
    echo -e "\t                     file.yaml"
    echo -e "\tset <container> <config.yaml>"
    echo -e "\t                     define a container as specified in <config.yaml>"
    echo -e "\t<container> perm create <account> <scope>"
    echo -e "\t                     create account with given scope"
    echo -e "\t<container> perm show <account>"
    echo -e "\t                     show account information"
    echo -e "\t<container> perm setenv <account> <name>"
    echo -e "\t                     set environment variable"
    echo -e "\t<container> write [<account|token>]"
    echo -e "\t                     read data from <stdin> and write as account"
    echo -e "\t<container> read [<account|token>]"
    echo -e "\t                     read data from <container> and write to <stdout>"
    echo ""
}

extract_yaml()
{
    eval "$3=$(grep "$2" $1 | head -n1 | cut -d ':' -f 2,3 | tr -d "[:space:]")"
}

invalid_syntax()
{
    echo "invalid option or syntax: ${args}"
    usage_info
    if [ "${BASH_SOURCE[0]}" != "${0}" ]; then
        return 1
    else
        exit 1
    fi
}

# read from & write into container =================
get_port()
{
    eval "$2=$(docker port hse | cut -d ":" -f 2)"
}

write_data()
{
    if $VERBOSE ; then
        echo "writing data into container"
    fi

    return_value=''; 
    get_port $1 return_value
    SC_PORT=$return_value
    command="cat - | curl -X POST -d @- -H 'Content-Type: application/json' http://localhost:${SC_PORT}/api/data"
    if $VERBOSE ; then
        echo "${command}"
    fi

    eval $command
}

read_data()
{
    if $VERBOSE ; then
        echo "reading data from container"
    fi

    return_value=''; 
    get_port $1 return_value
    SC_PORT=$return_value
    command="curl http://localhost:${SC_PORT}/api/data"
    if $VERBOSE ; then
        echo "${command}"
    fi

    eval $command
}

# start container =================
start_container()
{
    if $VERBOSE ; then
        echo "starting container"
    fi

    return_value=''; 
    extract_yaml "./${SC_CONFIG_FILE}" "image" return_value
    IMAGE=$return_value

    return_value=''; 
    extract_yaml "./${SC_CONFIG_FILE}" "port" return_value
    PORT=$return_value

    return_value=''; 
    extract_yaml "./${SC_CONFIG_FILE}" "name" return_value
    CONTAINER_NAME=$return_value

    CONFIG_PATH=$(dirname "$PWD/${SC_CONFIG_FILE}")
    CONFIG_FILE=$(basename "./${SC_CONFIG_FILE}")

    command="docker rm -f ${CONTAINER_NAME};"
    command="${command} docker run -d"
    command="${command} --name ${CONTAINER_NAME}"
    command="${command} -p ${PORT}:3000"
    command="${command} -v ${CONFIG_PATH}:/config"
    command="${command} -e CONFIG_FILE=${CONFIG_FILE}"
    command="${command} -e IMAGE_SHA256=\"\$(docker image ls --no-trunc -q ${IMAGE} | cut -c8-)\""
    command="${command} -e IMAGE_NAME=${IMAGE}"
    command="${command} ${IMAGE}"

    if $VERBOSE ; then
        echo "${command}"
    fi
    eval $command
}

# option handling =================
args=("$@") 
VERBOSE=false
if [[ $# -eq 0 ]]
then
    usage_info
    exit 0
fi 
while [ $# -gt 0 ]; do
    case "$1" in
        --version) 
            version_info
            exit 0
            ;;
        --help)
            version_info
            usage_info
            exit 0
            ;;
        --verbose|-v)
            VERBOSE=true
            ;;
        start)
            SC_MODE=start
            shift
            if [[ $# -eq 1 ]] 
            then
                SC_CONFIG_FILE=$1
                start_container
                exit 0
            else
                invalid_syntax
            fi
            ;;
        *)
            SC_CONTAINER_NAME=$1
            if [ "$(docker ps -q -f name=${SC_CONTAINER_NAME})" ]; 
            then
                shift
                case "$1" in
                    perm)
                        SC_MODE=perm
                        shift
                        case "$1" in
                            show)
                                shift
                                if [[ $# -eq 1 ]] 
                                then
                                    SC_ACCOUNT=$1
                                    show_perm
                                    exit 0
                                else
                                    invalid_syntax
                                fi
                                ;;
                            create)
                                shift
                                if [[ $# -eq 2 ]] 
                                then
                                    SC_ACCOUNT=$1
                                    SC_ACCOUNT_SCOPE=$2
                                    create_perm
                                    exit 0
                                else
                                    invalid_syntax
                                fi
                                ;;
                            setenv)
                                shift
                                if [[ $# -eq 2 ]] 
                                then
                                    SC_ACCOUNT=$1
                                    SC_ENV=$2
                                    set_permenv
                                    exit 0
                                else
                                    invalid_syntax
                                fi
                                ;;
                            *)
                                invalid_syntax
                                ;;
                        esac
                        ;;
                    write)
                        SC_MODE=write
                        write_data $SC_CONTAINER_NAME
                        ;;
                    read)
                        SC_MODE=read
                        read_data $SC_CONTAINER_NAME
                        ;;
                    *)
                        invalid_syntax
                        ;;
                esac
            else
                invalid_syntax
            fi
            ;;
    esac
    shift
done