adr-new

#!/bin/bash
set -e
eval "$($(dirname $0)/adr-config)"

## usage: adr new [-s SUPERCEDED] [-l TARGET:LINK:REVERSE-LINK] TITLE_TEXT...
##
## Creates a new, numbered ADR.  The TITLE_TEXT arguments are concatenated to
## form the title of the new ADR.  The ADR is opened for editing in the
## editor specified by the VISUAL or EDITOR environment variable (VISUAL is
## preferred; EDITOR is used if VISUAL is not set).  After editing, the
## file name of the ADR is output to stdout, so the command can be used in
## scripts.
##
## If the ADR directory contains a file `templates/template.md`, this is used as
## the template for the new ADR.  Otherwise a default template is used that
## follows the style described by Michael Nygard in this article:
##
##   http://thinkrelevance.com/blog/2011/11/15/documenting-architecture-decisions
##
## Options:
##
## -s SUPERCEDED   A reference (number or partial filename) of a previous
##                 decision that the new decision supercedes. A Markdown link
##                 to the superceded ADR is inserted into the Status section.
##                 The status of the superceded ADR is changed to record that
##                 it has been superceded by the new ADR.
##
## -l TARGET:LINK:REVERSE-LINK
##                 Links the new ADR to a previous ADR.  
##                 TARGET is a reference (number or partial filename) of a 
##                 previous decision. 
##                 LINK is the description of the link created in the new ADR.
##                 REVERSE-LINK is the description of the link created in the
##                 existing ADR that will refer to the new ADR.
##
## Multiple -s and -l options can be given, so that the new ADR can supercede 
## or link to multiple existing ADRs.
##
## E.g. to create a new ADR with the title "Use MySQL Database":
##
##     adr new Use MySQL Database
##
## E.g. to create a new ADR that supercedes ADR 12:
##
##     adr new -s 12 Use PostgreSQL Database
##
## E.g. to create a new ADR that supercedes ADRs 3 and 4, and amends ADR 5:
##
##     adr new -s 3 -s 4 -l "5:Amends:Amended by" Use Riak CRDTs to cope with scale
##

superceded=()
links=()

while getopts s:l: arg
do
    case "$arg" in
        s)
            superceded+=("$OPTARG")
            ;;
		l)
			links+=("$OPTARG")
			;;
        --)
            break
            ;;
        *)
            echo "Not implemented: $arg" >&2
            exit 1
            ;;
    esac
done
shift $((OPTIND-1))

dstdir=$("$adr_bin_dir/_adr_dir")
template="$ADR_TEMPLATE"
if [ -z $template ]
then
    template="$dstdir/templates/template.md"
    if [ ! -f "$template" ]
    then
        template="$adr_template_dir/template.md"
    fi
fi

title="$@"

if [ -z "$title" ]
then
    echo ERROR: no title given
    exit 1
fi

if [ -d $dstdir ]
then
    maxid=$(ls $dstdir | grep -Eo '^[0-9]+' | sed -e 's/^0*//' | sort -rn | head -1)
    newnum=$(($maxid + 1))
else
    newnum=1
fi

newid=$(printf "%04d" $newnum)
slug=$(echo -n $title | tr -Ccs [:alnum:] - | tr [:upper:] [:lower:] | sed -e 's/[^[:alnum:]]*$//' -e 's/^[^[:alnum:]]*//')
dstfile=$dstdir/$newid-$slug.md
date=${ADR_DATE:-$(date +%Y-%m-%d)}

mkdir -p $dstdir
cat $template | sed \
    -e "s|NUMBER|$newnum|" \
    -e "s|TITLE|$title|" \
    -e "s|DATE|$date|" \
    -e "s|STATUS|Accepted|" \
    > $dstfile

for target in "${superceded[@]}"
do
	"$adr_bin_dir/_adr_add_link" "$target" "Superceded by" "$dstfile"
	"$adr_bin_dir/_adr_remove_status" "Accepted" "$target"
	"$adr_bin_dir/_adr_add_link" "$dstfile" "Supercedes" "$target"
done

for l in "${links[@]}"
do
	target="$(echo $l | cut -d : -f 1)"
	forward_link="$(echo $l | cut -d : -f 2)"
	reverse_link="$(echo $l | cut -d : -f 3)"
	
	"$adr_bin_dir/_adr_add_link" "$dstfile" "$forward_link" "$target"
	"$adr_bin_dir/_adr_add_link" "$target" "$reverse_link" "$dstfile"
done

${VISUAL:-${EDITOR:-true}} $dstfile
echo $dstfile