Merge pull request #16 from SuperSandro2000/fix-lints

Fix remaining lints

7 files changed, 54 insertions, 18 deletions

diff --git a/bulk.go b/bulk.go
index 431fa76..d8b96ca 100644
--- a/bulk.go
+++ b/bulk.go
@@ -28,6 +28,7 @@ import (
 	"strings"
 
 	"github.com/majewsky/schwift/capabilities"
+	"github.com/majewsky/schwift/internal/errext"
 )
 
 // BulkUploadFormat enumerates possible archive formats for Container.BulkUpload().
@@ -214,7 +215,7 @@ func (a *Account) bulkDeleteSingle(objects []*Object, containers []*Container, o
 			numNotFound++
 			return nil
 		}
-		if statusErr, ok := err.(UnexpectedStatusCodeError); ok {
+		if statusErr, ok := errext.As[UnexpectedStatusCodeError](err); ok {
 			errs = append(errs, BulkObjectError{
 				ContainerName: containerName,
 				ObjectName:    objectName,
diff --git a/errors.go b/errors.go
index 06fa639..a79dd60 100644
--- a/errors.go
+++ b/errors.go
@@ -24,6 +24,8 @@ import (
 	"net/http"
 	"strconv"
 	"strings"
+
+	"github.com/majewsky/schwift/internal/errext"
 )
 
 var (
@@ -148,7 +150,7 @@ func (e BulkError) Error() string {
 //
 // It is safe to pass a nil error, in which case Is() always returns false.
 func Is(err error, code int) bool {
-	if e, ok := err.(UnexpectedStatusCodeError); ok {
+	if e, ok := errext.As[UnexpectedStatusCodeError](err); ok {
 		return e.ActualResponse.StatusCode == code
 	}
 	return false
diff --git a/internal/errext/errext.go b/internal/errext/errext.go
new file mode 100644
index 0000000..3655ba7
--- /dev/null
+++ b/internal/errext/errext.go
@@ -0,0 +1,26 @@
+package errext
+
+import "errors"
+
+// vendored from https://github.com/sapcc/go-bits/blob/master/errext/errext.go (also licensed Apache 2.0) to prevent go.mod go bump to 1.21
+
+// As is a variant of errors.As() that leverages generics to present a nicer interface.
+//
+//	//this code:
+//	var perr os.PathError
+//	if errors.As(err, &perr) {
+//		handle(perr)
+//	}
+//	//can be rewritten as:
+//	if perr, ok := errext.As[os.PathError](err); ok {
+//		handle(perr)
+//	}
+//
+// This is sometimes more verbose (like in this example), but allows to scope
+// the specific error variable to the condition's then-branch, and also looks
+// more idiomatic to developers already familiar with type casts.
+func As[T error](err error) (T, bool) {
+	var result T
+	ok := errors.As(err, &result)
+	return result, ok
+}
diff --git a/largeobject.go b/largeobject.go
index 83deddf..4def0d0 100644
--- a/largeobject.go
+++ b/largeobject.go
@@ -414,13 +414,13 @@ func (o *Object) AsNewLargeObject(sopts SegmentingOptions, topts *TruncateOption
 	//with the old segments
 	if topts != nil && topts.DeleteSegments {
 		lo, err := o.AsLargeObject()
-		switch err {
-		case nil:
+		switch {
+		case err == nil:
 			err := lo.Truncate(topts)
 			if err != nil {
 				return nil, err
 			}
-		case ErrNotLarge:
+		case errors.Is(err, ErrNotLarge):
 			//not an error, continue down below
 		default:
 			return nil, err //unexpected error
diff --git a/object.go b/object.go
index 0322906..8e2becd 100644
--- a/object.go
+++ b/object.go
@@ -25,6 +25,7 @@ import (
 	"crypto/sha1" //nolint:gosec // Used by swift
 	"crypto/sha256"
 	"encoding/hex"
+	"errors"
 	"fmt"
 	"hash"
 	"io"
@@ -135,6 +136,7 @@ func (o *Object) fetchHeaders(opts *RequestOptions) (*ObjectHeaders, error) {
 	if err != nil {
 		return nil, err
 	}
+	defer resp.Body.Close()
 
 	headers := ObjectHeaders{headersFromHTTP(resp.Header)}
 	return &headers, headers.Validate()
@@ -147,7 +149,7 @@ func (o *Object) fetchHeaders(opts *RequestOptions) (*ObjectHeaders, error) {
 //
 // A successful POST request implies Invalidate() since it may change metadata.
 func (o *Object) Update(headers ObjectHeaders, opts *RequestOptions) error {
-	_, err := Request{
+	resp, err := Request{
 		Method:            "POST",
 		ContainerName:     o.c.name,
 		ObjectName:        o.name,
@@ -156,6 +158,7 @@ func (o *Object) Update(headers ObjectHeaders, opts *RequestOptions) error {
 	}.Do(o.c.a.backend)
 	if err == nil {
 		o.Invalidate()
+		resp.Body.Close()
 	}
 	return err
 }
@@ -245,10 +248,10 @@ func (o *Object) Upload(content io.Reader, opts *UploadOptions, ropts *RequestOp
 		//chance of an inconsistent state following an upload error
 		var err error
 		lo, err = o.AsLargeObject()
-		switch err {
-		case nil:
+		switch {
+		case err == nil:
 			//okay, delete segments at the end
-		case ErrNotLarge:
+		case errors.Is(err, ErrNotLarge):
 			//okay, do not try to delete segments
 			lo = nil
 		default:
@@ -270,6 +273,7 @@ func (o *Object) Upload(content io.Reader, opts *UploadOptions, ropts *RequestOp
 		return err
 	}
 	o.Invalidate()
+	defer resp.Body.Close()
 
 	if hasher != nil {
 		expectedEtag := hex.EncodeToString(hasher.Sum(nil))
@@ -393,13 +397,13 @@ func (o *Object) Delete(opts *DeleteOptions, ropts *RequestOptions) error {
 		}
 		if exists {
 			lo, err := o.AsLargeObject()
-			switch err {
-			case nil:
+			switch {
+			case err == nil:
 				//is large object - delete segments and the object itself in one step
 				_, _, err := o.c.a.BulkDelete(append(lo.SegmentObjects(), o), nil, nil)
 				o.Invalidate()
 				return err
-			case ErrNotLarge:
+			case errors.Is(err, ErrNotLarge):
 				//not a large object - use regular DELETE request
 			default:
 				//unexpected error
@@ -408,7 +412,7 @@ func (o *Object) Delete(opts *DeleteOptions, ropts *RequestOptions) error {
 		}
 	}
 
-	_, err := Request{
+	resp, err := Request{
 		Method:            "DELETE",
 		ContainerName:     o.c.name,
 		ObjectName:        o.name,
@@ -417,6 +421,7 @@ func (o *Object) Delete(opts *DeleteOptions, ropts *RequestOptions) error {
 	}.Do(o.c.a.backend)
 	if err == nil {
 		o.Invalidate()
+		resp.Body.Close()
 	}
 	return err
 }
@@ -453,7 +458,7 @@ func (o *Object) Download(opts *RequestOptions) DownloadedObject {
 		ObjectName:        o.name,
 		Options:           opts,
 		ExpectStatusCodes: []int{http.StatusOK},
-	}.Do(o.c.a.backend)
+	}.Do(o.c.a.backend) //nolint:bodyclose // body is returned and must be closed by the user
 	var body io.ReadCloser
 	if err == nil {
 		newHeaders := ObjectHeaders{headersFromHTTP(resp.Header)}
@@ -498,7 +503,7 @@ func (o *Object) CopyTo(target *Object, opts *CopyOptions, ropts *RequestOptions
 		}
 	}
 
-	_, err := Request{
+	resp, err := Request{
 		Method:            "COPY",
 		ContainerName:     o.c.name,
 		ObjectName:        o.name,
@@ -508,6 +513,7 @@ func (o *Object) CopyTo(target *Object, opts *CopyOptions, ropts *RequestOptions
 	}.Do(o.c.a.backend)
 	if err == nil {
 		target.Invalidate()
+		resp.Body.Close()
 	}
 	return err
 }
diff --git a/request.go b/request.go
index 7b5da6d..01f052f 100644
--- a/request.go
+++ b/request.go
@@ -40,7 +40,7 @@ import (
 type RequestOptions struct {
 	Headers Headers
 	Values  url.Values
-	Context context.Context
+	Context context.Context //nolint: containedctx // ignored for now to not break the API
 }
 
 func cloneRequestOptions(orig *RequestOptions, additional Headers) *RequestOptions {
diff --git a/tests/bulk_upload_test.go b/tests/bulk_upload_test.go
index d810cf5..0bdcb4e 100644
--- a/tests/bulk_upload_test.go
+++ b/tests/bulk_upload_test.go
@@ -25,6 +25,7 @@ import (
 	"testing"
 
 	"github.com/majewsky/schwift"
+	"github.com/majewsky/schwift/internal/errext"
 )
 
 func TestBulkUploadSuccess(t *testing.T) {
@@ -62,7 +63,7 @@ func TestBulkUploadArchiveError(t *testing.T) {
 		)
 		expectInt(t, n, 0)
 		expectError(t, err, "400 Bad Request: Invalid Tar File: truncated header")
-		bulkErr := err.(schwift.BulkError) //nolint:errcheck
+		bulkErr, _ := errext.As[schwift.BulkError](err)
 		expectInt(t, bulkErr.StatusCode, 400)
 		expectString(t, bulkErr.OverallError, "Invalid Tar File: truncated header")
 		expectInt(t, len(bulkErr.ObjectErrors), 0)
@@ -87,7 +88,7 @@ func TestBulkUploadObjectError(t *testing.T) {
 		)
 		expectInt(t, n, 1)
 		expectError(t, err, "400 Bad Request (+1 object errors)")
-		bulkErr := err.(schwift.BulkError) //nolint:errcheck
+		bulkErr, _ := errext.As[schwift.BulkError](err)
 		expectInt(t, len(bulkErr.ObjectErrors), 1)
 		expectString(t, bulkErr.ObjectErrors[0].ContainerName, c.Name())
 		expectInt(t, bulkErr.ObjectErrors[0].StatusCode, 400)