Change the subject to be more terse

[dragonfly.git] / post-receive-email

#!/bin/sh
#
# Copyright (c) 2007 Andy Parkins
#
# An example hook script to mail out commit update information.  This hook
# sends emails listing new revisions to the repository introduced by the
# change being reported.  The rule is that (for branch updates) each commit
# will appear on one email and one email only.
#
# This hook is stored in the contrib/hooks directory.  Your distribution
# will have put this somewhere standard.  You should make this script
# executable then link to it in the repository you would like to use it in.
# For example, on debian the hook is stored in
# /usr/share/doc/git-core/contrib/hooks/post-receive-email:
#
#  chmod a+x post-receive-email
#  cd /path/to/your/repository.git
#  ln -sf /usr/share/doc/git-core/contrib/hooks/post-receive-email hooks/post-receive
#
# This hook script assumes it is enabled on the central repository of a
# project, with all users pushing only to it and not between each other.  It
# will still work if you don't operate in that style, but it would become
# possible for the email to be from someone other than the person doing the
# push.
#
# Config
# ------
# hooks.mailinglist
#   This is the list that all pushes will go to; leave it blank to not send
#   emails for every ref update.
# hooks.announcelist
#   This is the list that all pushes of annotated tags will go to.  Leave it
#   blank to default to the mailinglist field.  The announce emails lists
#   the short log summary of the changes since the last annotated tag.
# hooks.envelopesender
#   If set then the -f option is passed to sendmail to allow the envelope
#   sender address to be set
# hooks.emailprefix
#   All emails have their subjects prefixed with this prefix, or "[SCM]"
#   if emailprefix is unset, to aid filtering
#
# Notes
# -----
# All emails include the headers "X-Git-Refname", "X-Git-Oldrev",
# "X-Git-Newrev", and "X-Git-Reftype" to enable fine tuned filtering and
# give information for debugging.
#

# ---------------------------- Functions

#
# Top level email generation function.  This decides what type of update
# this is and calls the appropriate body-generation routine after outputting
# the common header
#
# Note this function doesn't actually generate any email output, that is
# taken care of by the functions it calls:
#  - generate_email_header
#  - generate_create_XXXX_email
#  - generate_update_XXXX_email
#  - generate_delete_XXXX_email
#  - generate_email_footer
#
generate_email()
{
        # --- Arguments
        oldrev=$(git rev-parse $1)
        newrev=$(git rev-parse $2)
        refname="$3"

        # --- Interpret
        # 0000->1234 (create)
        # 1234->2345 (update)
        # 2345->0000 (delete)
        if expr "$oldrev" : '0*$' >/dev/null
        then
                change_type="create"
        else
                if expr "$newrev" : '0*$' >/dev/null
                then
                        change_type="delete"
                else
                        change_type="update"
                fi
        fi

        # --- Get the revision types
        newrev_type=$(git cat-file -t $newrev 2> /dev/null)
        oldrev_type=$(git cat-file -t "$oldrev" 2> /dev/null)
        case "$change_type" in
        create|update)
                rev="$newrev"
                rev_type="$newrev_type"
                ;;
        delete)
                rev="$oldrev"
                rev_type="$oldrev_type"
                ;;
        esac

        # The revision type tells us what type the commit is, combined with
        # the location of the ref we can decide between
        #  - working branch
        #  - tracking branch
        #  - unannoted tag
        #  - annotated tag
        case "$refname","$rev_type" in
                refs/tags/*,commit)
                        # un-annotated tag
                        refname_type="tag"
                        short_refname=${refname##refs/tags/}
                        ;;
                refs/tags/*,tag)
                        # annotated tag
                        refname_type="annotated tag"
                        short_refname=${refname##refs/tags/}
                        # change recipients
                        if [ -n "$announcerecipients" ]; then
                                recipients="$announcerecipients"
                        fi
                        ;;
                refs/heads/*,commit)
                        # branch
                        refname_type="branch"
                        short_refname=${refname##refs/heads/}
                        ;;
                refs/remotes/*,commit)
                        # tracking branch
                        refname_type="tracking branch"
                        short_refname=${refname##refs/remotes/}
                        echo >&2 "*** Push-update of tracking branch, $refname"
                        echo >&2 "***  - no email generated."
                        exit 0
                        ;;
                *)
                        # Anything else (is there anything else?)
                        echo >&2 "*** Unknown type of update to $refname ($rev_type)"
                        echo >&2 "***  - no email generated"
                        exit 1
                        ;;
        esac

        # Check if we've got anyone to send to
        if [ -z "$recipients" ]; then
                case "$refname_type" in
                        "annotated tag")
                                config_name="hooks.announcelist"
                                ;;
                        *)
                                config_name="hooks.mailinglist"
                                ;;
                esac
                echo >&2 "*** $config_name is not set so no email will be sent"
                echo >&2 "*** for $refname update $oldrev->$newrev"
                exit 0
        fi

        # The email subject will contain the best description of the ref
        # that we can build from the parameters
        set_describe $rev

        # Call the correct body generation function
        fn_name=general
        case "$refname_type" in
        "tracking branch"|branch)
                fn_name=branch
                ;;
        "annotated tag")
                fn_name=atag
                ;;
        esac

        case "$fn_name" in
        branch)
                split=""
                revs=$(list_${change_type}_branch_revs 2>/dev/null)
                if [ "$(echo "$revs" | wc -l)" -gt 1 ]
                then
                        split=1
                fi

                if [ "$change_type" != "update" ]
                then
                        set_update_branch_subject
                        {
                        generate_email_header
                        generate_${change_type}_branch_email
                        summarize_branch_revs
                        generate_email_footer
                        } | $send_mail
                fi

                for rev in $revs
                do
                        
                        oldrev=
                        newrev=$rev

                        # set_update_branch_subject will return false if the
                        # commit is boring (no change).  Then we don't even
                        # send a mail.
                        set_update_branch_subject || continue
                        {
                        generate_email_header
                        print_change_info $newrev
                        summarize_branch_revs
                        generate_email_footer
                        } | $send_mail
                done
                ;;

        *)
                {
                generate_email_header
                generate_${change_type}_${fn_name}_email
                generate_email_footer
                } | $send_mail
                ;;
        esac
}

set_describe()
{
        describe=$(git describe --abbrev=4 $1 2>/dev/null || git rev-parse --short $1)
        describe=$(echo "$describe" | sed -e 's/-/./g;s/^v//;')
}

generate_email_header()
{
        # --- Email (all stdout will be the email)
        # Generate header
        print_change_type=" ${change_type}d"
        case "$change_type" in
        "update")
                print_change_type=""
                ;;
        esac

        print_refname="$refname_type "
        case "$refname_type" in
        "branch")
                print_refname=""
                ;;
        esac

        cat <<-EOF
        To: $recipients
        Subject: ${emailprefix}$describe $print_refname$short_refname${print_change_type}$detail
        X-Git-Refname: $refname
        X-Git-Reftype: $refname_type
        X-Git-Newrev: $newrev

        EOF
}

generate_email_footer()
{
        SPACE=" "
        cat <<-EOF

        --${SPACE}
        $projectdesc
        EOF
}

# --------------- Branches

#
# Called for the creation of a branch
#
generate_create_branch_email()
{
        # This is a new branch and so oldrev is not valid
        echo "        at  $newrev ($newrev_type)"
}

list_create_branch_revs()
{
        git rev-parse --not --branches | grep -v $(git rev-parse $refname) |
        git rev-list --reverse --stdin $newrev
}

#
# Called for the change of a pre-existing branch
#
generate_update_branch_email()
{
        # XXX only valid for fast forwards

        # List all the revisions from baserev to newrev in a kind of
        # "table-of-contents"; note this list can include revisions that
        # have already had notification emails and is present to show the
        # full detail of the change from rolling back the old revision to
        # the base revision and then forward to the new revision
        for rev in $(git rev-list $oldrev..$newrev)
        do
                revtype=$(git cat-file -t "$rev")
                echo "       via  $rev ($revtype)"
        done

        echo "      from  $oldrev ($oldrev_type)"

        echo ""
}

skip_diff_tree_parent()
{
        if [ -n "$oldrev" ]
        then
                cat
        else
                tail +2
        fi
}

set_update_branch_subject()
{
        set_describe $newrev

        detail=$(git diff-tree -r -c --name-only $oldrev${oldrev:+..}$newrev |
                        skip_diff_tree_parent |
                        sed -E -e 's#/([^/]*)$# \1#' |
                        awk 'pos > 74 {
                                printf "\n";
                                pos = 0;
                        }
                        $1 != lastdir {
                                printf " %s", $1;
                                pos += length($1) + 1;
                                lastdir = $1;
                        }
                        $2 != "" {
                                printf " %s", $2;
                                pos += length($2) + 1;
                        }')
        [ -n "$(git diff-tree -r --name-only --cc $oldrev${oldrev:+..}$newrev |
                skip_diff_tree_parent)" ]
}

list_update_branch_revs()
{
        git rev-parse --not --branches | grep -v $(git rev-parse $refname) |
        git rev-list --reverse --stdin $oldrev..$newrev
}

summarize_branch_revs()
{
        echo "Summary of changes:"
        git diff-tree --stat --summary --find-copies-harder $oldrev${oldrev:+..}$newrev | skip_diff_tree_parent

        if [ -n "$gitweburl" ]
        then
                echo ""
                echo "$gitweburl?p=$reponame;a=commitdiff;h=$newrev${oldrev:+;hp=}$oldrev"
        fi
}

print_change_info()
{
        git rev-list -n 1 --pretty $1
}

#
# Called for the deletion of a branch
#
generate_delete_branch_email()
{
        echo "       was  $oldrev"
        echo ""
        echo $LOGEND
        git show -s --pretty=oneline $oldrev
        echo $LOGEND
}

# --------------- Annotated tags

#
# Called for the creation of an annotated tag
#
generate_create_atag_email()
{
        echo "        at  $newrev ($newrev_type)"

        generate_atag_email
}

#
# Called for the update of an annotated tag (this is probably a rare event
# and may not even be allowed)
#
generate_update_atag_email()
{
        echo "        to  $newrev ($newrev_type)"
        echo "      from  $oldrev (which is now obsolete)"

        generate_atag_email
}

#
# Called when an annotated tag is created or changed
#
generate_atag_email()
{
        # Use git for-each-ref to pull out the individual fields from the
        # tag
        eval $(git for-each-ref --shell --format='
        tagobject=%(*objectname)
        tagtype=%(*objecttype)
        tagger=%(taggername)
        tagged=%(taggerdate)' $refname
        )

        echo "   tagging  $tagobject ($tagtype)"
        case "$tagtype" in
        commit)

                # If the tagged object is a commit, then we assume this is a
                # release, and so we calculate which tag this tag is
                # replacing
                prevtag=$(git describe --abbrev=0 $newrev^ 2>/dev/null)

                if [ -n "$prevtag" ]; then
                        echo "  replaces  $prevtag"
                fi
                ;;
        *)
                echo "    length  $(git cat-file -s $tagobject) bytes"
                ;;
        esac
        echo " tagged by  $tagger"
        echo "        on  $tagged"

        echo ""
        echo $LOGBEGIN

        # Show the content of the tag message; this might contain a change
        # log or release notes so is worth displaying.
        git cat-file tag $newrev | sed -e '1,/^$/d'

        echo ""
        case "$tagtype" in
        commit)
                # Only commit tags make sense to have rev-list operations
                # performed on them
                if [ -n "$prevtag" ]; then
                        # Show changes since the previous release
                        git rev-list --pretty=short "$prevtag..$newrev" | git shortlog
                else
                        # No previous tag, show all the changes since time
                        # began
                        git rev-list --pretty=short $newrev | git shortlog
                fi
                ;;
        *)
                # XXX: Is there anything useful we can do for non-commit
                # objects?
                ;;
        esac

        echo $LOGEND
}

#
# Called for the deletion of an annotated tag
#
generate_delete_atag_email()
{
        echo "       was  $oldrev"
        echo ""
        echo $LOGEND
        git show -s --pretty=oneline $oldrev
        echo $LOGEND
}

# --------------- General references

#
# Called when any other type of reference is created (most likely a
# non-annotated tag)
#
generate_create_general_email()
{
        echo "        at  $newrev ($newrev_type)"

        generate_general_email
}

#
# Called when any other type of reference is updated (most likely a
# non-annotated tag)
#
generate_update_general_email()
{
        echo "        to  $newrev ($newrev_type)"
        echo "      from  $oldrev"

        generate_general_email
}

#
# Called for creation or update of any other type of reference
#
generate_general_email()
{
        # Unannotated tags are more about marking a point than releasing a
        # version; therefore we don't do the shortlog summary that we do for
        # annotated tags above - we simply show that the point has been
        # marked, and print the log message for the marked point for
        # reference purposes
        #
        # Note this section also catches any other reference type (although
        # there aren't any) and deals with them in the same way.

        echo ""
        if [ "$newrev_type" = "commit" ]; then
                echo $LOGBEGIN
                git show --no-color --root -s --pretty=medium $newrev
                echo $LOGEND
        else
                # What can we do here?  The tag marks an object that is not
                # a commit, so there is no log for us to display.  It's
                # probably not wise to output git cat-file as it could be a
                # binary blob.  We'll just say how big it is
                echo "$newrev is a $newrev_type, and is $(git cat-file -s $newrev) bytes long."
        fi
}

#
# Called for the deletion of any other type of reference
#
generate_delete_general_email()
{
        echo "       was  $oldrev"
        echo ""
        echo $LOGEND
        git show -s --pretty=oneline $oldrev
        echo $LOGEND
}

send_mail()
{
        if [ -n "$envelopesender" ]; then
                /usr/sbin/sendmail -t -f "$envelopesender"
        else
                /usr/sbin/sendmail -t
        fi
}

# ---------------------------- main()

# --- Constants
LOGBEGIN="- Log -----------------------------------------------------------------"
LOGEND="-----------------------------------------------------------------------"

# --- Config
# Set GIT_DIR either from the working directory, or from the environment
# variable.
GIT_DIR=$(git rev-parse --git-dir 2>/dev/null)
if [ -z "$GIT_DIR" ]; then
        echo >&2 "fatal: post-receive: GIT_DIR not set"
        exit 1
fi

projectdesc=$(sed -ne '1p' "$GIT_DIR/description")
# Check if the description is unchanged from it's default, and shorten it to
# a more manageable length if it is
if expr "$projectdesc" : "Unnamed repository.*$" >/dev/null
then
        projectdesc="UNNAMED PROJECT"
fi

recipients=$(git config hooks.mailinglist)
announcerecipients=$(git config hooks.announcelist)
envelopesender=$(git config hooks.envelopesender)
emailprefix=$(git config hooks.emailprefix || echo '[SCM] ')
gitweburl=$(git config hooks.gitweburl)
reponame=$(git config hooks.reponame || basename $(realpath $GIT_DIR))

# --- Main loop
# Allow dual mode: run from the command line just like the update hook, or
# if no arguments are given then run as a hook script
if [ -n "$1" -a -n "$2" -a -n "$3" ]; then
        # Output to the terminal in command line mode - if someone wanted to
        # resend an email; they could redirect the output to sendmail
        # themselves
        send_mail=cat
        generate_email $2 $3 $1
else
        while read oldrev newrev refname
        do
                send_mail=send_mail
                generate_email $oldrev $newrev $refname
        done
fi