fix: S3 HeadObject NotFound error never being returned

[aajtodd]

Issues:

fixes: #2084

Description:

Removes S3 HeadObject customization that stripped the model of all errors for that operation. It's unclear why we decided to adopt this behavior. The code references aws/aws-sdk-go#1208 as justification but the NoSuchKey error in question is not what is modeled. Both HeadBucket and HeadObject only list NotFound as an error.

This also would appear to fix the ObjectExists and ObjectNotExists waiters.

Backwards compatibility concerns

The NotFound error was never possible before this so if customers have defined code paths for it they may now trigger them. The NotFound error type is still an APIError though and any code path that implemented a work around to check the ErrorCode() directly will still work since NotFound implements APIError

e.g.

	var apiErr smithy.APIError
	if errors.As(err, &apiErr) && apiErr.ErrorCode() == "NotFound" { ... }  // still works fine with `NotFound` error

Testing

package main

import (
	"context"
	"errors"
	"fmt"
	"github.com/aws/aws-sdk-go-v2/aws"
	"github.com/aws/aws-sdk-go-v2/config"
	"github.com/aws/aws-sdk-go-v2/service/s3"
	"github.com/aws/aws-sdk-go-v2/service/s3/types"
	"log"
)

func main() {
	ctx := context.Background()
	if err := issue(ctx); err != nil {
		log.Fatal(err)
	}
}

func issue(ctx context.Context) error {
	cfg, err := config.LoadDefaultConfig(
		ctx,
		config.WithClientLogMode(aws.LogRequestWithBody|aws.LogResponseWithBody),
		config.WithSharedConfigProfile("dev-admin-west"),
	)

	if err != nil {
		return err
	}
	client := s3.NewFromConfig(cfg)

	bucketResp, err := client.HeadBucket(ctx, &s3.HeadBucketInput{
		Bucket: aws.String("does-not-exist-foobar-go-test"),
	})
	fmt.Printf("resp: %v, err: %v\n", bucketResp, err)

	var notFoundErr *types.NotFound
	if errors.As(err, &notFoundErr) {
		fmt.Printf("HeadBucket returned not found: %v\n", notFoundErr)
	} else {
		fmt.Println("HeadBucket did not return not found")
	}

	notFoundErr = nil
	bucket := "<my-bucket>"
	objResp, err := client.HeadObject(ctx, &s3.HeadObjectInput{
		Bucket: aws.String(bucket),
		Key:    aws.String("does-not-exist-key"),
	})
	fmt.Printf("resp: %v, err: %v\n", objResp, err)

	if errors.As(err, &notFoundErr) {
		fmt.Printf("HeadObject returned not found: %v\n", notFoundErr)
	} else {
		fmt.Println("HeadObject did not return not found")
	}
	return nil
}

Output Before

SDK 2023/05/25 12:41:35 DEBUG Response
HTTP/1.1 404 Not Found
Connection: close
Content-Type: application/xml
Date: Thu, 25 May 2023 16:41:34 GMT
Server: AmazonS3

resp: <nil>, err: operation error S3: HeadBucket, https response error StatusCode: 404, RequestID: K5FRB1PK1V6F4TX5, HostID: 1234=, NotFound: 
HeadBucket returned not found: NotFound: 


SDK 2023/05/25 12:41:36 DEBUG Response
HTTP/1.1 404 Not Found
Connection: close
Content-Type: application/xml
Date: Thu, 25 May 2023 16:41:35 GMT
Server: AmazonS3

resp: <nil>, err: operation error S3: HeadObject, https response error StatusCode: 404, RequestID: Y7PBZF6SNBBCPFJG, HostID: 1234=, api error NotFound: Not Found
HeadObject did not return not found

Output After

SDK 2023/05/25 13:12:46 DEBUG Response
HTTP/1.1 404 Not Found
Connection: close
Content-Type: application/xml
Date: Thu, 25 May 2023 17:12:46 GMT
Server: AmazonS3
X-Amz-Id-2: 4AoYTha5idyFA6zjSODv4ymcw1lT4cGedEJ8hT8XUY9w4+A3DYpPzxHtwAb7X47nQ1710wpRzks=
X-Amz-Request-Id: MG3KCK7QJD3YYEKT

resp: <nil>, err: operation error S3: HeadBucket, https response error StatusCode: 404, RequestID: MG3KCK7QJD3YYEKT, HostID: 4AoYTha5idyFA6zjSODv4ymcw1lT4cGedEJ8hT8XUY9w4+A3DYpPzxHtwAb7X47nQ1710wpRzks=, NotFound: 
HeadBucket returned not found: NotFound: 

SDK 2023/05/25 13:12:47 DEBUG Response
HTTP/1.1 404 Not Found
Connection: close
Content-Type: application/xml
Date: Thu, 25 May 2023 17:12:46 GMT
Server: AmazonS3

resp: <nil>, err: operation error S3: HeadObject, https response error StatusCode: 404, RequestID: FR98XVN62NFF1FPS, HostID: 1234=, NotFound: 
HeadObject returned not found: NotFound: 

Appendix

Model

Links to S3 model never work because it's too large, pasted here for convenience

        "com.amazonaws.s3#HeadBucket": {
            "type": "operation",
            "input": {
                "target": "com.amazonaws.s3#HeadBucketRequest"
            },
            "output": {
                "target": "smithy.api#Unit"
            },
            "errors": [
                {
                    "target": "com.amazonaws.s3#NotFound"
                }
            ],



        "com.amazonaws.s3#HeadObject": {
            "type": "operation",
            "input": {
                "target": "com.amazonaws.s3#HeadObjectRequest"
            },
            "output": {
                "target": "com.amazonaws.s3#HeadObjectOutput"
            },
            "errors": [
                {
                    "target": "com.amazonaws.s3#NotFound"
                }
            ],

[stefansundin]

types.Nound 🤔 should be types.NotFound?