adding sccache to greatly increase cargo build runs

Dockerfile.remotebuild

@@ -15,7 +15,11 @@ RUN rustup component add rustfmt && cargo install rustfmt || true
 RUN rustup default stable
 
 # Install build essentials and curl
-RUN apk update && apk add curl build-base
+RUN apk update && apk add curl build-base sccache
+
+# Set the Shared Compilation Cache for Cargo to use sccache
+# This greatly improves build times when running concurrent builds
+ENV RUSTC_WRAPPER=/usr/bin/sccache
 
 # Install buf
 RUN GO111MODULE=on GOBIN=/usr/local/bin go install github.com/bufbuild/buf/cmd/[email protected]

cmd/substreams/remote-build.go

@@ -65,6 +65,7 @@ func remoteBuildE(cmd *cobra.Command, args []string) error {
 		return fmt.Errorf("failed to read file: %w", err)
 	}
 
+	fmt.Println("Sending build request ...")
 	client := pbbuild.NewBuildServiceClient(conn)
 	buildResponse, err := client.Build(context.Background(), &pbbuild.BuildRequest{
 		SourceCode:     b,

remotebuild/main.go

@@ -83,7 +83,7 @@ func (s *Server) Build(
 	} else {
 		s.logger.Info("keeping temp dir", "dir", tempDir)
 	}
-
+	s.logger.Debug("temp dir", "dir", tempDir)
 	s.logger.Debug("source code size", "size", len(req.Msg.SourceCode))
 	err = unzip(req.Msg.SourceCode, tempDir)
 	if err != nil {