New branch - Prow jobs automation

add-branch.sh

#!/bin/bash

set -eo pipefail

die () {
    echo >&2 "$@"
    show_help
    exit 1
}


show_help() {
  local usage
  usage="
$(basename "$0")

Usage:
  ./$(basename "$0") [flags]
   
Options:
  --repo       
    name of the repository to clone jobs in

  --file
    file to apply changes to

  --previous
    new branch version    

  --new
    new branch version  

  --dry-run        
    Boolean flag indicating if actual changes on the file or printed to STDOUT

  -h, --help       
    Help message.

Example:
  ./$(basename "$0") --repo maistra/istio --from 2.2 --to 2.3 --file presubmits.yaml   
"

  echo "$usage"
}

TMP_FILE=$(mktemp -q /tmp/"${file}".XXXXXX)
function stdout_or_in_place {
    if $dryRun; then
        cat
    else       
        cat > "${TMP_FILE}" && cat "${TMP_FILE}" > "${file}"
    fi
}


dryRun=false

while test $# -gt 0; do
  case "$1" in
    -h|--help)
            show_help
            exit 0
            ;;
    --dry-run)
            dryRun=true
            shift
            ;;
    --repo)
            if [[ $1 == "--"* ]]; then
                repo="${2/--/}"
                shift
            fi
            shift
            ;;
    --previous)
            if [[ $1 == "--"* ]]; then
                previous="${2/--/}"
                shift
            fi
            shift
            ;;
    --new)
            if [[ $1 == "--"* ]]; then
                branch="${2/--/}"
                shift
            fi
            shift
            ;;
    --file)
            if [[ $1 == "--"* ]]; then
                file="${2/--/}"
                shift
            fi
            shift
            ;;
    *)
            die "$(basename "$0"): unknown flag $(echo $1 | cut -d'=' -f 1)"
            exit 1
            ;;
  esac
done

if [ -z "$repo" ] || [ -z "$file" ] || [ -z "$branch" ] || [ -z "$previous" ]; then
    die "Missing required flags!"
fi

if ! command -v yq &>/dev/null; then
  echo "yq is required. Please follow installation guide https://github.com/mikefarah/yq/#install"
  exit 1
fi

## Add new branch
matchingBranches="(.*.${repo}.[] | select (.branches[] == \"^${previous}$\"))"

yq "${matchingBranches}.branches |= reverse" "${file}"  \
    | yq "${matchingBranches}.branches += [ \"^${branch}$\" ]" - \
    | yq "${matchingBranches}.branches |= reverse" - \
    | stdout_or_in_place

clone-jobs.sh

#!/bin/bash

set -eo pipefail

die () {
    echo >&2 "$@"
    show_help
    exit 1
}


show_help() {
  local usage
  usage="
$(basename "$0")

Usage:
  ./$(basename "$0") [flags]
   
Options:
  --repo       
    name of the repository to clone jobs in

  --file
    file to apply changes to

  --from
    old branch version

  --to
    new branch version  

  --dry-run        
    Boolean flag indicating if actual changes on the file or printed to STDOUT

  -h, --help       
    Help message.

Example:
  ./$(basename "$0") --repo maistra/istio --from 2.2 --to 2.3 --file presubmits.yaml   
"

  echo "$usage"
}

TMP_FILE=$(mktemp -q /tmp/"${file}".XXXXXX)
function stdout_or_in_place {
    if $dryRun; then
        cat
    else       
        cat > "${TMP_FILE}" && cat "${TMP_FILE}" > "${file}"
    fi
}


dryRun=false

while test $# -gt 0; do
  case "$1" in
    -h|--help)
            show_help
            exit 0
            ;;
    --dry-run)
            dryRun=true
            shift
            ;;
    --repo)
            if [[ $1 == "--"* ]]; then
                repo="${2/--/}"
                shift
            fi
            shift
            ;;
    --from)
            if [[ $1 == "--"* ]]; then
                from="${2/--/}"
                shift
            fi
            shift
            ;;
    --to)
            if [[ $1 == "--"* ]]; then
                to="${2/--/}"
                shift
            fi
            shift
            ;;
    --file)
            if [[ $1 == "--"* ]]; then
                file="${2/--/}"
                shift
            fi
            shift
            ;;
    *)
            die "$(basename "$0"): unknown flag $(echo $1 | cut -d'=' -f 1)"
            exit 1
            ;;
  esac
done

if [ -z "$repo" ] || [ -z "$file" ] || [ -z "$from" ] || [ -z "$to" ]; then
    die "Missing required flags!"
fi

if ! command -v yq &>/dev/null; then
  echo "yq is required. Please follow installation guide https://github.com/mikefarah/yq/#install"
  exit 1
fi

## Duplicate jobs
yq "[.*.${repo}.[] | select (.name == \"*-${from}\")]" "${file}" \
    | sed "s/-${from}/-${to}/g" \
    | yq ea "select(fi == 0) as \$job | select(fi==1) | .*.${repo} += \$job " - "${file}" \
    | stdout_or_in_place

Usage (passing --dry-run won't overwrite the file):

REPOS=('maistra/istio-must-gather' 'maistra/header-append-filter')
printf '%s\n' ${REPOS[@]} | xargs -I REPO ./add-branch.sh --file presubmits.yaml --repo REPO --previous maistra-2.3 --new maistra-2.4

./clone-jobs.sh --repo maistra/istio --from 2.2 --to 2.3 --file presubmits.yaml