Fix sync response link populating (#32)

Author: pdoerner

nexus/client.go

@@ -219,6 +219,25 @@ func (c *HTTPClient) StartOperation(
 	if err != nil {
 		return nil, err
 	}
+
+	links, err := getLinksFromHeader(response.Header)
+	if err != nil {
+		// Have to read body here to check if it is a Failure.
+		body, err := readAndReplaceBody(response)
+		if err != nil {
+			return nil, err
+		}
+		return nil, fmt.Errorf(
+			"%w: %w",
+			newUnexpectedResponseError(
+				fmt.Sprintf("invalid links header: %q", response.Header.Values(headerLink)),
+				response,
+				body,
+			),
+			err,
+		)
+	}
+
 	// Do not close response body here to allow successful result to read it.
 	if response.StatusCode == http.StatusOK {
 		return &ClientStartOperationResult[*LazyValue]{
@@ -229,6 +248,7 @@ func (c *HTTPClient) StartOperation(
 					prefixStrippedHTTPHeaderToNexusHeader(response.Header, "content-"),
 				},
 			},
+			Links: links,
 		}, nil
 	}
 
@@ -247,18 +267,6 @@ func (c *HTTPClient) StartOperation(
 		if info.State != OperationStateRunning {
 			return nil, newUnexpectedResponseError(fmt.Sprintf("invalid operation state in response info: %q", info.State), response, body)
 		}
-		links, err := getLinksFromHeader(response.Header)
-		if err != nil {
-			return nil, fmt.Errorf(
-				"%w: %w",
-				newUnexpectedResponseError(
-					fmt.Sprintf("invalid links header: %q", response.Header.Values(headerLink)),
-					response,
-					body,
-				),
-				err,
-			)
-		}
 		return &ClientStartOperationResult[*LazyValue]{
 			Pending: &OperationHandle[*LazyValue]{
 				Operation: operation,

nexus/operation.go

@@ -125,7 +125,7 @@ func (h *syncOperation[I, O]) Start(ctx context.Context, input I, options StartO
 	if err != nil {
 		return nil, err
 	}
-	return &HandlerStartOperationResultSync[O]{Value: o, Links: options.Links}, err
+	return &HandlerStartOperationResultSync[O]{Value: o}, err
 }
 
 // A Service is a container for a group of operations.
@@ -344,7 +344,10 @@ func StartOperation[I, O any](ctx context.Context, client *HTTPClient, operation
 		if err := result.Successful.Consume(&o); err != nil {
 			return nil, err
 		}
-		return &ClientStartOperationResult[O]{Successful: o}, nil
+		return &ClientStartOperationResult[O]{
+			Successful: o,
+			Links:      result.Links,
+		}, nil
 	}
 	handle := OperationHandle[O]{client: client, Operation: operation.Name(), ID: result.Pending.ID}
 	return &ClientStartOperationResult[O]{

nexus/start_test.go

@@ -5,6 +5,7 @@ import (
 	"context"
 	"fmt"
 	"io"
+	"net/url"
 	"testing"
 	"time"
 
@@ -47,7 +48,7 @@ func (h *successHandler) StartOperation(ctx context.Context, service, operation
 		return nil, HandlerErrorf(HandlerErrorTypeBadRequest, "invalid 'User-Agent' header: %q", options.Header.Get("User-Agent"))
 	}
 
-	return &HandlerStartOperationResultSync[any]{Value: body, Links: options.Links}, nil
+	return &HandlerStartOperationResultSync[any]{Value: body}, nil
 }
 
 func TestSuccess(t *testing.T) {
@@ -110,6 +111,7 @@ func TestClientRequestID(t *testing.T) {
 		t.Run(c.name, func(t *testing.T) {
 			result, err := client.StartOperation(ctx, "foo", nil, c.request)
 			require.NoError(t, err)
+			require.Equal(t, c.request.Links, result.Links)
 			response := result.Successful
 			require.NotNil(t, response)
 			var responseBody []byte
@@ -165,7 +167,7 @@ func (h *echoHandler) StartOperation(ctx context.Context, service, operation str
 			Data:   data,
 		}
 	}
-	return &HandlerStartOperationResultSync[any]{Value: output}, nil
+	return &HandlerStartOperationResultSync[any]{Value: output, Links: options.Links}, nil
 }
 
 func TestReaderIO(t *testing.T) {
@@ -182,6 +184,7 @@ func TestReaderIO(t *testing.T) {
 		name   string
 		input  any
 		header Header
+		links  []Link
 	}{
 		{
 			name:   "content",
@@ -192,14 +195,24 @@ func TestReaderIO(t *testing.T) {
 			name:   "reader",
 			input:  reader,
 			header: Header{"input-type": "reader"},
+			links: []Link{{
+				URL: &url.URL{
+					Scheme:   "https",
+					Host:     "example.com",
+					Path:     "/path/to/something",
+					RawQuery: "param=value",
+				},
+				Type: "url",
+			}},
 		},
 	}
 
 	for _, tc := range testCases {
 		tc := tc
 		t.Run(tc.name, func(t *testing.T) {
-			result, err := client.StartOperation(ctx, "foo", tc.input, StartOperationOptions{Header: tc.header})
+			result, err := client.StartOperation(ctx, "foo", tc.input, StartOperationOptions{Header: tc.header, Links: tc.links})
 			require.NoError(t, err)
+			require.Equal(t, tc.links, result.Links)
 			response := result.Successful
 			require.NotNil(t, response)
 			var operationResult string