log2dch

#!/bin/bash

VERBOSITY=0
TEMP_D=""
COMMIT_URL=${COMMIT_URL:-https://github.com/canonical/cloud-init/commit/}
BUG_URL=${BUG_URL:-https://pad.lv/}

FILTER_LIST=( "lp-to-git-user" "Merge pull request" "Merge branch" )

error() { echo "$@" 1>&2; }
fail() { local r=$?;  [ $r -eq 0 ] && r=1; failrc "$r" "$@"; }
failrc() { local r=$1; shift; [ $# -eq 0 ] || error "$@"; exit "$r"; }

Usage() {
    cat <<EOF
Usage: ${0##*/} [ options ] [input-file]

   Read input-file which is a git or bzr log and create a
   debian/changelog formatted file from the result.

   options:
      --vcs VCS         which log format is this ('git', 'auto', 'bzr')
                        default: auto
      --skip-bugs       Do not print bug info
      --trello          output in markdown for checklist items in trello
      --hackmd          output markdown formated for hackmd.io
      --commit-url=URL  use a different commit url.
                        default=$COMMIT_URL
      --bug-url=URL     use a different bug url.
                        default=$BUG_URL

   Assuming git style log commit messages, this reads the makes the
   summary line into a debian/changelog style entry with author
   in [] and mentions bugs fixed (bzr via '--fixes', git via LP: #
   in commit messages.)

   Examples:

  * bzr based simplestreams (bzr branch lp:simplestreams)

      $ bzr log -r-5.. | log2dch
        - Keystone v3 Support (LP: #1686437)
        - tools/ubuntu_versions.py: Exclude old versions by version not name
        - fix flake8
        - tests: change to having http server select its own port
        - flake8: fix style errors reported by pycodestyle 2.1.0

  * git based cloud-init (git clone http://git.launchpad.net/cloud-init)

      $ git log HEAD~5.. | log2dch
        - tests: execute: support command as string [Joshua Powers]
        - schema and docs: Add jsonschema to resizefs and bootcmd modules
          [Chad Smith]
        - tools: Add xkvm script, wrapper around qemu-system [Joshua Powers]
        - vmware customization: return network config format
          [Sankar Tanguturi] (LP: #1675063)
        - Ec2: only attempt to operate at local mode on known platforms.
          (LP: #1715128)
EOF
}

bad_Usage() { Usage 1>&2; [ $# -eq 0 ] || error "$@"; return 1; }
cleanup() {
    [ -z "${TEMP_D}" -o ! -d "${TEMP_D}" ] || rm -Rf "${TEMP_D}"
}

debug() {
    local level=${1}; shift;
    [ "${level}" -gt "${VERBOSITY}" ] && return
    error "${@}"
}

bzr_log_to_dch() {
    local line="" commit="" bugs="" bug=""
    local func="${1:-print_dch}"
    local skip_bugs="${2:-false}"
    while :; do
        read line || break
        case "$line" in
            revno:\ *)
                if [ -n "$commit" ]; then
	            $skip_bugs && bugs=""
                    $func "$commit" "$subject" "$author" "$bugs"
                fi
                commit=${line#*: }
                bugs=""
                author=""
                subject=""
                ;;
            author:*) author="${line#author: }";;
            fixes\ bug:*)
                # fixes bug: https://launchpad.net/bugs/1618429
                bug="#${line##*/}"
                bugs="${bugs:+${bugs}, }${bug}";;
            message:)
                read subject;;
        esac
    done
    if [ -n "$commit" ]; then
	$skip_bugs && bugs=""
        $func "$commit" "$subject" "$author" "$bugs"
    fi
}


print_hackmd() {
    local commit="$1" subject="$2" author="$3" bugs="$4" bug_tracker="$5"
    local aname="" abugs="" buf="" bug="" t=""
    local url="${COMMIT_URL}"
    t=${commit#????????}
    local bugmd="" pre=""
    for bug in ${bugs}; do
        bug=${bug%,}
        [ -z "$bugmd" ] && pre="LP: "
        bugmd="${bugmd}[$pre${bug}](${BUG_URL}$bug),"
    done
    bugmd=${bugmd%,}
    t=${commit#????????}
    buf="${bugmd:+${bugmd} }${subject}"
    buf="${buf} \[[${commit%$t}]($url${commit%$t})\]"
    if [[ $buf == 'tests:'* ]]; then
	buf="~~NOTEST ${buf}~~"
    fi
    for filter in "${FILTER_LIST[@]}"; do
        if [[ "$subject" != "${subject/$filter//}" ]]; then
            return  # skip echo because our filter string matched
	fi
    done
    echo "- $buf"
}

print_trello() {
    local commit="$1" subject="$2" author="$3" bugs="$4" bug_tracker="$5"
    local aname="" abugs="" buf="" bug="" t=""
    local url="${COMMIT_URL}"
    t=${commit#????????}
    buf="[${commit%$t}](${url}${commit%$t})"
    for bug in ${bugs}; do
        bug=${bug%,}
        buf="${buf:+${buf} }[${bug}](${BUG_URL}$bug)"
    done
    if [ "${subject#*\(#}" = "$subject" ]; then
       pr_num=""
    else
        # replace PR # with a markdown link
        pr_num=${subject#*\(#}  # redact leading prefix before.*(#
        pr_num=${pr_num%)}      # truncate trailing ) if present
        subject=${subject/$pr_num/[${pr_num}](http://github.com/canonical/cloud-init/pull/${pr_num})}
    fi
    buf="${buf:+${buf} }$subject"
    for filter in "${FILTER_LIST[@]}"; do
        if [[ "$subject" != "${subject/$filter//}" ]]; then
            return  # skip echo because our filter string matched
	fi
    done
    echo "$buf"
}

print_dch() {
    local commit="$1" subject="$2" author="$3" bugs="$4" bug_tracker="$5"
    local aname="" abugs="" indent="    - " indent2="      " ll=79
    local i=""
    aname=${author% <*}
    case "$aname" in
        Chad\ Smith|Lucas\ Moura|James\ Falcon|Brett\ Holman|Alberto\ Contreras) aname="";;
    esac
    abugs="${aname:+ [${aname}]}${bugs:+ (${bug_tracker}: ${bugs})}"
    for filter in "${FILTER_LIST[@]}"; do
        if [[ "$subject" != "${subject/$filter//}" ]]; then
            return  # skip echo because our filter string matched
	fi
    done
    if [ $((${#subject}+${#abugs})) -le $((ll-${#indent})) ]; then
        echo "${indent}${subject}${abugs}"
    elif [ ${#subject} -ge $((ll-${#indent})) ]; then
        echo "${subject}${abugs}" |
            fmt --width=$((ll-${#indent})) |
            sed -e "1s/^/${indent}/; 1n;" \
                -e 's/^[ ]*//' \
                -e '/^[ ]*$/d' -e "s/^/$indent2/" -e 's/[ ]\+$//'

    else
        ( echo "${subject}"; echo "${abugs}" ) |
            fmt --width=$((ll-${#indent})) |
            sed -e "1s/^/${indent}/; 1n;" \
                -e 's/^[ ]*//' \
                -e '/^[ ]*$/d' -e "s/^/$indent2/" -e 's/[ ]\+$//'
    fi
}

git_log_to_dch() {
    local line="" commit="" bugs=""
    local func=${1:-print_dch}
    local skip_bugs=${2:-false}
    local bug_tracker="LP"
    while :; do
        read line || break
        case "$line" in
            commit\ *)
                if [ -n "$commit" ]; then
	            if [ "${skip_bugs}" = "true" ]; then
                       bugs=""  # Don't append bugs referenced in commit body

                       # Replace "LP: #" with "LP:" if present in subject
                       # to avoid trigging SRU validation of bugs
                       subject=${subject/LP: #/LP:}
                    fi
                    "$func" "$commit" "$subject" "$author" "$bugs" "$bug_tracker"
                fi
                commit=${line#commit }
                bugs=""
                author=""
                subject=""
                ;;
            Author:*) author="${line#Author: }";;
            LP:*) bug_tracker="LP"; bugs="${bugs:+${bugs}, }${line#*: }";;
            Fixes\ GH*|Closes\ GH*)
                bug_tracker="GH";
                bug="${line#*\ GH-}";
                [ ! -z "${bug##*[!0-9]*}" ] && bugs="${bugs:+${bugs}, }$bug";;
            "") [ -z "$subject" ] && read -r subject;;
        esac
    done
    if [ -n "$commit" ]; then
	if [ "${skip_bugs}" = "true" ]; then
            bugs=""  # Don't append bugs referenced in commit body

            # Replace "LP: #" with "LP:" if present in subject
            # to avoid trigging SRU validation of bugs
            subject=${subject/LP: #/LP:}
        fi
        $func "$commit" "$subject" "$author" "$bugs" "$bug_tracker"
    fi
}

assert_temp_d() {
    TEMP_D=$(mktemp -d "${TMPDIR:-/tmp}/${0##*/}.XXXXXX") ||
        fail "failed creating temp directory";
}

main() {
    local short_opts="ht:v"
    local long_opts="bug-url:,commit-url:,hackmd,help,skip-bugs,trello,vcs:,verbose"
    local getopt_out=""
    getopt_out=$(getopt --name "${0##*/}" \
        --options "${short_opts}" --long "${long_opts}" -- "$@") &&
        eval set -- "${getopt_out}" ||
        { bad_Usage; return; }

    local cur="" next="" vcs="auto" input="-" omode="dch" skip_bugs=false

    while [ $# -ne 0 ]; do
        cur="$1"; next="$2";
        case "$cur" in
            -h|--help) Usage ; exit 0;;
               --skip-bugs) skip_bugs=true;;
               --trello) omode="trello";;
               --hackmd) omode="hackmd";;
               --commit-url) COMMIT_URL="$next";;
               --bug-url) BUG_URL="$next";;
            -t|--vcs) vcs="$next";
                case "$vcs" in
                    auto|git|bzr)
                        bad_Usage "vcs must be one of auto, git, bzr.";
                        return;;
                esac
                ;;
            -v|--verbose) VERBOSITY=$((VERBOSITY+1));;
            --) shift; break;;
        esac
        shift;
    done

    [ $# -le 1 ] || { bad_Usage "got $# arguments, expected 0 or 1"; return; }

    [ $# -eq 1 ] && { input="$1"; shift; }
    trap cleanup EXIT

    local oinput="$input"
    if [ "$vcs" = "auto" ]; then
        if [ "$input" = "-" ]; then
            assert_temp_d
            input="${TEMP_D}/input"
            cat > "$input"
        fi
        if grep -q '^revno:' "$input"; then
            vcs="bzr"
        elif grep -q '^commit ' "$input"; then
            vcs="git"
        else
            error "failed to figure out vcs type in $oinput"
            return
        fi
    fi

    if [ "$input" != "-" ]; then
        exec < "$input" ||
            { error "failed to open $input for reading"; return 1; }
    fi

    case "$omode" in
        trello) printer="print_trello";;
        hackmd) printer="print_hackmd";;
        *) printer="print_dch";;
    esac
    local func="${vcs}_log_to_dch"
    "$func" "$printer" $skip_bugs
    return
}

main "$@"
# vi: ts=4 expandtab