run.sh

#!/bin/sh

set -ex

rver="$(curl --silent https://www.perforce.com/perforce/doc.current/user/p4vnotes.txt |
	sed -n 'N;N;s/.* Version \(20[0-9][0-9]\.[1-9][0-9]*\).*/\1/p;q')"
url=https://cdist2.perforce.com/perforce/r${rver#20}/bin.macosx1015x86_64/helix-core-server.tgz

test -n "$LAST_MODIFIED" ||
LAST_MODIFIED="Wed, 14 Jul 2021 13:53:46 GMT"

curl -I --silent --header "If-Modified-Since: $LAST_MODIFIED" $url | tr -d '\r' >out
first_line=$(head -n 1 <out)

case "$first_line,$rver" in
"HTTP/1.1 404 Not Found",2021.4)
	# Seems that Perforce does not offer 21.4 for public download
	rver=2021.2
	url=https://cdist2.perforce.com/perforce/r${rver#20}/bin.macosx1015x86_64/helix-core-server.tgz
	curl -I --silent --header "If-Modified-Since: $LAST_MODIFIED" $url | tr -d '\r' >out
	first_line=$(head -n 1 <out)
	;;
esac

case "$first_line" in
"HTTP/1.1 304 Not Modified")
    ;; # still up to date; nothing needs to be changed
"HTTP/1.1 200 OK")
    # not up to date
    new_last_modified="$(sed -n 's/^Last-Modified: //p' <out)"

    file=helix-core-server.tgz
    if test ! -f $file ||
        case "$(uname -s)" in
	Darwin)
	    test $(date -j -f "%a, %d %B %Y %H:%M:%S GMT" "$new_last_modified" +%s) -gt $(stat -f %m $file)
	    ;;
	*)
	    test $(date -d "$new_last_modified" +%s) -gt $(stat -c %Y $file)
	    ;;
	esac
    then
	curl --silent -o helix-core-server.tgz $url
    fi

    new_version="$(tar Oxvf $file Versions.txt | sed -n 's/^Rev\. P4D\/[^\/]*\/\(20[^\/]*\)\/\([^ ]*\).*/\1,\2/p')"
    new_sha256="$(openssl dgst -sha256 $file)"
    new_sha256="${new_sha256##* }"

    file=Casks/perforce.rb
    if test ! -d homebrew-cask/.git
    then
        git init homebrew-cask
        echo "/$file" >homebrew-cask/.git/info/sparse-checkout
        git -C homebrew-cask config core.sparseCheckout true
    fi
    git -C homebrew-cask fetch https://github.com/Homebrew/homebrew-cask/ master
    git -C homebrew-cask reset --hard FETCH_HEAD

    old_version=$(sed -n 's/^ *version "\(.*\)"$/\1/p' <homebrew-cask/$file)
    commit_message="Update perforce from $old_version to $new_version"
    sed -e 's/^\( *version "\)[^"]*/\1'"$new_version/" \
        -e 's/^\( *sha256 "\)[^"]*/\1'"$new_sha256/" \
        <homebrew-cask/$file >homebrew-cask/$file.new
    mv homebrew-cask/$file.new homebrew-cask/$file
    git -C homebrew-cask commit -m "$commit_message" $file

    test -n "$GITHUB_PUSH_TOKEN" || {
        echo "Need a push token!" >&2
        exit 1
    }
    git -C homebrew-cask push https://dscho:$GITHUB_PUSH_TOKEN@github.com/gitgitgadget/homebrew-cask +HEAD:refs/heads/perforce

    # Open the PR
    body="$(printf '%s\\n' \
        "<!-- If there’s a checkbox you can’t complete for any reason, that's okay, just explain in detail why you weren’t able to do so. -->" \
        '' \
        'After making all changes to the cask:' \
        '' \
        '- [ ] `brew cask audit --download {{cask_file}}` is error-free.' \
        '- [ ] `brew cask style --fix {{cask_file}}` reports no offenses.' \
        '- [x] The commit message includes the cask’s name and version.' \
        '- [x] The submission is for [a stable version](https://github.com/Homebrew/homebrew-cask/blob/master/doc/development/adding_a_cask.md#finding-a-home-for-your-cask) or [documented exception](https://github.com/Homebrew/homebrew-cask/blob/master/doc/development/adding_a_cask.md#but-there-is-no-stable-version).' \
        '' \
        'This PR was generated by [a script](https://github.com/gitgitgadget/keep-homebrew-perforce-up-to-date/blob/master/run.sh) running in [an Azure Pipeline](https://dev.azure.com/gitgitgadget/git/_build?definitionId=11&_a=summary).')"
    curl -XPOST -i -d '{"head":"gitgitgadget:perforce","base":"master","title":"'"$commit_message"'","body":"'"$body"'"}' \
        https://dscho:$GITHUB_PUSH_TOKEN@api.github.com/repos/Homebrew/homebrew-cask/pulls | tee out
    if ! grep "^\(HTTP/1.1 201 Created\|HTTP/2 201\)" out
    then
        echo "Failed to open a Pull Request" >&2
        exit 1
    fi

    # Update the last.modified variable in this build definition
    if test -n "$AZURE_PIPELINE_PAT"
    then
        url="$SYSTEM_TEAMFOUNDATIONSERVERURI$SYSTEM_TEAMPROJECTID/_apis/build/definitions/$SYSTEM_DEFINITIONID?api-version=5.0"
        original_json="$(curl --silent -u "PAT:$AZURE_PIPELINE_PAT" -H "Accept: application/json; api-version=5.0; excludeUrls=true" "$url")"
        json="$(echo "$original_json" | sed 's/\("last.modified":{"value":"\)[^"]*/\1'"$new_last_modified"/)"
        curl --silent -X PUT -u "PAT:$AZURE_PIPELINE_PAT" -H "Content-Type: application/json" -d "$json" "$url"
    fi
    ;;
*)
    echo "Unexpected curl result:" >&2
    cat out >&2
    exit 1
    ;;
esac