[BUG][GO] Generated API Imports Deprecated io/ioutil Package

Created by: gonzogomez

Description

The generator will generate the following go code with the deprecated io/ioutil package:

import (
        "bytes"
        "context"
        "io/ioutil"
        "net/http"
        "net/url"
        "strings"
        "os"
)

io/ioutil package has been deprecated as of Go 1.16, the same functionality is now provided by the io and os packages.

openapi-generator version

Version tested :

• 6.2.1
• master

OpenAPI declaration file content or url

https://github.com/OpenAPITools/openapi-generator/blob/master/modules/openapi-generator/src/test/resources/3_0/petstore.yaml

Command line used for generation

./run-in-docker.sh generate -i modules/openapi-generator/src/test/resources/3_0/petstore.yaml -g go -o /gen/out/go-petstore -p packageName=petstore

Steps to reproduce

Generate the go code with petstore.yaml ./run-in-docker.sh generate -i modules/openapi-generator/src/test/resources/3_0/petstore.yaml -g go -o /gen/out/go-petstore -p packageName=petstore

Suggest a fix/enhancement

Modify the following mustache template files to use io and os instead of io/ioutil

• api.ustache
• client.mustache
• signing.mustache