genai: add debug printing of requests (#178)

Sometimes it is useful to see the requests that are being
sent to the service. Add a facility for this.

genai/caching.go

@@ -64,9 +64,11 @@ func (c *Client) CreateCachedContent(ctx context.Context, cc *CachedContent) (*C
 	}
 	pcc := cc.toProto()
 	pcc.Model = Ptr(fullModelName(cc.Model))
-	return c.cachedContentFromProto(c.cc.CreateCachedContent(ctx, &pb.CreateCachedContentRequest{
+	req := &pb.CreateCachedContentRequest{
 		CachedContent: pcc,
-	}))
+	}
+	debugPrint(req)
+	return c.cachedContentFromProto(c.cc.CreateCachedContent(ctx, req))
 }
 
 // GetCachedContent retrieves the CachedContent with the given name.
@@ -108,10 +110,12 @@ func (c *Client) UpdateCachedContent(ctx context.Context, cc *CachedContent, ccu
 	if ccu.Expiration.ExpireTime.IsZero() {
 		mask = "ttl"
 	}
-	return c.cachedContentFromProto(c.cc.UpdateCachedContent(ctx, &pb.UpdateCachedContentRequest{
+	req := &pb.UpdateCachedContentRequest{
 		CachedContent: cc2.toProto(),
 		UpdateMask:    &fieldmaskpb.FieldMask{Paths: []string{mask}},
-	}))
+	}
+	debugPrint(req)
+	return c.cachedContentFromProto(c.cc.UpdateCachedContent(ctx, req))
 }
 
 // ListCachedContents lists all the CachedContents associated with the project and location.

genai/client.go

@@ -226,7 +226,7 @@ func (m *GenerativeModel) newGenerateContentRequest(contents ...*Content) (*pb.G
 		if m.CachedContentName != "" {
 			cc = &m.CachedContentName
 		}
-		return &pb.GenerateContentRequest{
+		req := &pb.GenerateContentRequest{
 			Model:             m.fullName,
 			Contents:          transformSlice(contents, (*Content).toProto),
 			SafetySettings:    transformSlice(m.SafetySettings, (*SafetySetting).toProto),
@@ -236,6 +236,8 @@ func (m *GenerativeModel) newGenerateContentRequest(contents ...*Content) (*pb.G
 			SystemInstruction: m.SystemInstruction.toProto(),
 			CachedContent:     cc,
 		}
+		debugPrint(req)
+		return req
 	})
 }
 
@@ -327,10 +329,12 @@ func (m *GenerativeModel) newCountTokensRequest(contents ...*Content) (*pb.Count
 	if err != nil {
 		return nil, err
 	}
-	return &pb.CountTokensRequest{
+	req := &pb.CountTokensRequest{
 		Model:                  m.fullName,
 		GenerateContentRequest: gcr,
-	}, nil
+	}
+	debugPrint(req)
+	return req, nil
 }
 
 // Info returns information about the model.
@@ -340,6 +344,7 @@ func (m *GenerativeModel) Info(ctx context.Context) (*ModelInfo, error) {
 
 func (c *Client) modelInfo(ctx context.Context, fullName string) (*ModelInfo, error) {
 	req := &pb.GetModelRequest{Name: fullName}
+	debugPrint(req)
 	res, err := c.mc.GetModel(ctx, req)
 	if err != nil {
 		return nil, err

genai/debug.go

@@ -0,0 +1,38 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// This file contains debugging support functions.
+
+package genai
+
+import (
+	"fmt"
+	"os"
+
+	"google.golang.org/protobuf/encoding/prototext"
+	"google.golang.org/protobuf/proto"
+)
+
+// printRequests controls whether request protobufs are written to stderr.
+var printRequests = false
+
+func debugPrint(m proto.Message) {
+	if !printRequests {
+		return
+	}
+	fmt.Fprintln(os.Stderr, "--------")
+	fmt.Fprintf(os.Stderr, "%T\n", m)
+	fmt.Fprint(os.Stderr, prototext.Format(m))
+	fmt.Fprintln(os.Stderr, "^^^^^^^^")
+}

genai/embed.go

@@ -76,6 +76,7 @@ func newEmbedContentRequest(model string, tt TaskType, title string, parts []Par
 		taskType := pb.TaskType(tt)
 		req.TaskType = &taskType
 	}
+	debugPrint(req)
 	return req
 }
 

genai/files.go

@@ -74,7 +74,9 @@ func (c *Client) UploadFile(ctx context.Context, name string, r io.Reader, opts
 
 // GetFile returns the named file.
 func (c *Client) GetFile(ctx context.Context, name string) (*File, error) {
-	pf, err := c.fc.GetFile(ctx, &pb.GetFileRequest{Name: userNameToServiceName(name)})
+	req := &pb.GetFileRequest{Name: userNameToServiceName(name)}
+	debugPrint(req)
+	pf, err := c.fc.GetFile(ctx, req)
 	if err != nil {
 		return nil, err
 	}
@@ -84,7 +86,9 @@ func (c *Client) GetFile(ctx context.Context, name string) (*File, error) {
 // DeleteFile deletes the file with the given name.
 // It is an error to delete a file that does not exist.
 func (c *Client) DeleteFile(ctx context.Context, name string) error {
-	return c.fc.DeleteFile(ctx, &pb.DeleteFileRequest{Name: userNameToServiceName(name)})
+	req := &pb.DeleteFileRequest{Name: userNameToServiceName(name)}
+	debugPrint(req)
+	return c.fc.DeleteFile(ctx, req)
 }
 
 // userNameToServiceName converts a name supplied by the user to a name required by the service.