A small shell script that I wrote to download the plantuml jar and convert iuml files in a directory to svg or png

build-diagrams.sh

#! /usr/bin/env bash

PLANTUML_EXECUTABLE="plantuml.jar"
PLANTUML_URL="http://sourceforge.net/projects/plantuml/files/plantuml.jar/download"

function usage {
    printf "Usage: $0 [-h] [-f <FORMAT>]\n\\ntWhere <FORMAT> can be:\n\t\tpng,svg" 1>&2
    exit 1
}

function is_bin_in_path {
  builtin type -P "$1" &> /dev/null
}

function download_bin {
    printf "Checking for needed tools…\n"

    is_bin_in_path curl
    
    if [[ $? -eq 0 ]]; then
        DOWNLOAD_TOOL=curl
        DOWNLOAD_FLAGS="-L"
        DOWNLOAD_OUTPUT_FLAG="-o"
    else
        printf "cURL not found searching for wget…\n"
        is_bin_in_path wget
        if [[ $? -eq 0 ]]; then
            DOWNLOAD_TOOL=wget
            DOWNLOAD_FLAGS="-q"
            DOWNLOAD_OUTPUT_FLAG="-O"
        else
            printf "Tools for downloading not found in your system, exiting now\n"
            exit 1
        fi
    fi

    printf "Downloading…\n"

    $DOWNLOAD_TOOL ${DOWNLOAD_FLAGS} ${PLANTUML_URL} ${DOWNLOAD_OUTPUT_FLAG} ${PLANTUML_EXECUTABLE}
}

### Start of actual operation ###

printf "Welcome to Diagrams builder\n"
printf "Checking for java in system…\n"

is_bin_in_path java

if [[ $? -ne 0 ]]; then
    printf "Java is necessary for running this script. Please set your JAVA_HOME and add Java to your PATH"
fi

printf "Checking if executable is available in current directory…\n"
if ! [[ -f ${PLANTUML_EXECUTABLE} ]]; then
    download_bin
fi

EXTENSION="png"
while getopts ":hf:" option; do
    case "${option}" in
        h)
            usage
            ;;
        f)
            EXTENSION=${OPTARG}
            ;;
        :)
            printf "Option -${OPTARG} requires an argument. Use -h to see possible arguments" >&2
            exit 1
            ;;
        *)
            ;;
    esac
done
shift $((OPTIND-1))

if [[ ${EXTENSION} = "png" ]]; then
    FORMAT="-tpng"
#elif [[ ${EXTENSION} = "pdf" ]]; then
#    FORMAT="-tpdf"
elif [[ ${EXTENSION} = "svg" ]]; then
    FORMAT="-tsvg"
else   
    printf "Unsupported format: $FORMAT\n"
    exit 1
fi

printf "Using format: ${EXTENSION} for files in current directory…\n"

for file_ in *.iuml; do
    [ -f "$file_" ] || break
    printf "Creating diagram for file ${file_}\n"
    java -jar plantuml.jar ${FORMAT} -o "out" ${file_}
    printf "Diagram created at out/${file_%.iuml}.${EXTENSION}\n"
done