Script using jq and yq to upgrade kubernetes ingress version from networking.k8s.io/v1beta1 to networking.k8s.io/v1

convert-ingress-version.sh

#!/usr/bin/env bash

# Upgrade ingress resource api version to v1.
#
# USAGE: 
#   convert-ingress-version.sh [OPTIONS] <FILE>
#
# OPTIONS:
#   -i  update the yaml file inplace.
#
# ------------------------------------------------------------
# apiVersion: networking.k8s.io/v1beta1 -> networking.k8s.io/v1`
# spec.backend -> spec.defaultBackend
# serviceName -> service.name
# servicePort -> service.port.name (for string values)
# servicePort -> service.port.number (for numeric values)
# pathType: ImplementationSpecific (no longer has a default value in v1; "Exact", "Prefix", or "ImplementationSpecific" must be specified)
# ------------------------------------------------------------

set -euo pipefail

options=()
file=$1

if [ "$file" == "-i" ]; then
    options=(--inplace)    
    file=$2
    echo "Converting inline: $2..."
fi

if ! yq eval -e '.apiVersion == "networking.k8s.io/v1beta1"' "$file" >/dev/null 2>&1; then 
    echo "error: wrong apiVersion"
    exit 1
fi

# spec modifications
modified_spec=$(
    yq eval -j '.spec' "$file" |
    jq '
        def get_port: 
            if .servicePort|type == "number" then 
                {number: .servicePort} 
            else 
                {name: .servicePort} 
            end;

        def convert_backend: {service: {name: .serviceName, port: get_port}};

        with_entries(if .key == "backend" 
            then (.key = "defaultBackend" | .value |= convert_backend) 
            else . 
        end) |

        .rules[].http.paths[] |= {
            path, 
            pathType: (.pathType // "ImplementationSpecific"), 
            backend: (.backend | convert_backend)
        } 
    '
)

export modified_spec

# root level modifications, preserving annotations and comments
yq -P "${options[@]}" eval '.apiVersion = "networking.k8s.io/v1" | .spec = env(modified_spec)' "$file"