avoid assuming region is us-west-2 when provider is gcp (#1306)

* avoid assuming region is us-west-2 when provider is gcp

* allow region to be set through env vars in mcp server

* use us-central1 for default gcp region in mcp estimate tool

* add support for gcp estimation in mcp server

* show an interactive selector if provider is not specified before estimate

* create a GetRegion util to get default region for each provider

Author: jordanstephens

src/cmd/cli/command/estimate.go

@@ -3,7 +3,6 @@ package command
 import (
 	"fmt"
 
-	"github.com/DefangLabs/defang/src/pkg"
 	"github.com/DefangLabs/defang/src/pkg/cli"
 	cliClient "github.com/DefangLabs/defang/src/pkg/cli/client"
 	"github.com/DefangLabs/defang/src/pkg/term"
@@ -27,12 +26,25 @@ func makeEstimateCmd() *cobra.Command {
 				return err
 			}
 
+			if providerID == cliClient.ProviderAuto {
+				_, err = interactiveSelectProvider([]cliClient.ProviderID{
+					cliClient.ProviderAWS,
+					cliClient.ProviderGCP,
+				})
+				if err != nil {
+					return fmt.Errorf("failed to select provider: %w", err)
+				}
+			}
+
 			var previewProvider cliClient.Provider = &cliClient.PlaygroundProvider{FabricClient: client}
 
 			// default to development mode if not specified; TODO: when mode is not specified, show an interactive prompt
 			if mode.Value() == defangv1.DeploymentMode_MODE_UNSPECIFIED {
 				mode = Mode(defangv1.DeploymentMode_DEVELOPMENT)
 			}
+			if region == "" {
+				region = cliClient.GetRegion(providerID) // This sets the default region based on the provider
+			}
 
 			estimate, err := cli.RunEstimate(ctx, project, client, previewProvider, providerID, region, mode.Value())
 			if err != nil {
@@ -47,6 +59,6 @@ func makeEstimateCmd() *cobra.Command {
 	}
 
 	estimateCmd.Flags().VarP(&mode, "mode", "m", fmt.Sprintf("deployment mode; one of %v", allModes()))
-	estimateCmd.Flags().StringP("region", "r", pkg.Getenv("AWS_REGION", "us-west-2"), "which cloud region to estimate")
+	estimateCmd.Flags().StringP("region", "r", "", "which cloud region to estimate")
 	return estimateCmd
 }

src/pkg/cli/client/region.go

@@ -0,0 +1,16 @@
+package client
+
+import "github.com/DefangLabs/defang/src/pkg"
+
+func GetRegion(provider ProviderID) string {
+	switch provider {
+	case ProviderAWS:
+		return pkg.Getenv("AWS_REGION", "us-west-2") // Default region for AWS
+	case ProviderGCP:
+		return pkg.Getenv("CLOUDSDK_COMPUTE_REGION", "us-central1") // Default region for GCP
+	case ProviderDO:
+		return pkg.Getenv("DO_REGION", "nyc3") // Default region for DigitalOcean
+	default:
+		return "" // No default region for unsupported providers
+	}
+}

src/pkg/mcp/tools/estimate.go

@@ -26,6 +26,12 @@ func setupEstimateTool(s *server.MCPServer, cluster string) {
 			mcp.Description("Path to current working directory"),
 		),
 
+		mcp.WithString("provider",
+			mcp.Description("The cloud provider to estimate costs for. Supported options are AWS or GCP"),
+			mcp.DefaultString("AWS"),
+			mcp.Enum("AWS", "GCP"),
+		),
+
 		mcp.WithString("deployment_mode",
 			mcp.Description("The deployment mode for the estimate. Options are AFFORDABLE, BALANCED or HIGH AVAILABILITY."),
 			mcp.DefaultString("AFFORDABLE"),
@@ -53,6 +59,11 @@ func setupEstimateTool(s *server.MCPServer, cluster string) {
 			modeString = "AFFORDABLE" // Default to AFFORDABLE if not provided
 		}
 
+		providerString, ok := request.Params.Arguments["provider"].(string)
+		if !ok {
+			providerString = "aws" // Default to AWS if not provided
+		}
+
 		// This logic is replicated from src/cmd/cli/command/mode.go
 		// I couldn't figure out how to import it without circular dependencies
 		modeString = strings.ToUpper(modeString)
@@ -89,10 +100,21 @@ func setupEstimateTool(s *server.MCPServer, cluster string) {
 		}
 
 		defangProvider := &cliClient.PlaygroundProvider{FabricClient: client}
-		providerID := cliClient.ProviderAWS // Default to AWS
+
+		var providerID cliClient.ProviderID
+		err = providerID.Set(providerString)
+		if err != nil {
+			term.Error("Invalid provider specified", "error", err)
+			return mcp.NewToolResultErrorFromErr("Invalid provider specified", err), nil
+		}
 
 		term.Debug("Function invoked: cli.RunEstimate")
-		estimate, err := cli.RunEstimate(ctx, project, client, defangProvider, providerID, "us-west-2", mode)
+		var region string
+		if region == "" {
+			region = cliClient.GetRegion(providerID) // This sets the default region based on the provider
+		}
+
+		estimate, err := cli.RunEstimate(ctx, project, client, defangProvider, providerID, region, mode)
 		if err != nil {
 			return mcp.NewToolResultErrorFromErr("Failed to run estimate", err), nil
 		}