Replace CloudScoped with ValidatingStrategy for credential chain filtering

NEXT_CHANGELOG.md

@@ -8,6 +8,8 @@
 
 ### Bug Fixes
 
+ * Restore `NewCredentialsChain` return type to `CredentialsStrategy` interface ([#1516](https://github.com/databricks/databricks-sdk-go/pull/1516)).
+
 ### Documentation
 
 ### Internal Changes

config/auth_azure_cli.go

@@ -11,6 +11,7 @@ import (
 
 	"golang.org/x/oauth2"
 
+	"github.com/databricks/databricks-sdk-go/common/environment"
 	"github.com/databricks/databricks-sdk-go/config/credentials"
 	"github.com/databricks/databricks-sdk-go/logger"
 )
@@ -28,6 +29,11 @@ func (c AzureCliCredentials) Name() string {
 	return "azure-cli"
 }
 
+// Cloud implements [CloudScoped.Cloud].
+func (c AzureCliCredentials) Cloud() environment.Cloud {
+	return environment.CloudAzure
+}
+
 // implementing azureHostResolver for ensureWorkspaceUrl to work
 func (c AzureCliCredentials) tokenSourceFor(
 	ctx context.Context, cfg *Config, _, resource string) oauth2.TokenSource {

config/auth_azure_client_secret.go

@@ -8,6 +8,7 @@ import (
 	"golang.org/x/oauth2"
 	"golang.org/x/oauth2/clientcredentials"
 
+	"github.com/databricks/databricks-sdk-go/common/environment"
 	"github.com/databricks/databricks-sdk-go/config/credentials"
 	"github.com/databricks/databricks-sdk-go/logger"
 )
@@ -19,6 +20,11 @@ func (c AzureClientSecretCredentials) Name() string {
 	return "azure-client-secret"
 }
 
+// Cloud implements [CloudScoped.Cloud].
+func (c AzureClientSecretCredentials) Cloud() environment.Cloud {
+	return environment.CloudAzure
+}
+
 func (c AzureClientSecretCredentials) tokenSourceFor(
 	ctx context.Context, cfg *Config, aadEndpoint, resource string) oauth2.TokenSource {
 	return (&clientcredentials.Config{

config/auth_azure_github_oidc.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"time"
 
+	"github.com/databricks/databricks-sdk-go/common/environment"
 	"github.com/databricks/databricks-sdk-go/config/credentials"
 	"github.com/databricks/databricks-sdk-go/config/experimental/auth"
 	"github.com/databricks/databricks-sdk-go/config/experimental/auth/oidc"
@@ -22,6 +23,11 @@ func (c AzureGithubOIDCCredentials) Name() string {
 	return "github-oidc-azure"
 }
 
+// Cloud implements [CloudScoped.Cloud].
+func (c AzureGithubOIDCCredentials) Cloud() environment.Cloud {
+	return environment.CloudAzure
+}
+
 // Configure implements [CredentialsStrategy.Configure].
 func (c AzureGithubOIDCCredentials) Configure(ctx context.Context, cfg *Config) (credentials.CredentialsProvider, error) {
 	if cfg.AzureClientID == "" || cfg.Host == "" || cfg.AzureTenantID == "" || cfg.ActionsIDTokenRequestURL == "" || cfg.ActionsIDTokenRequestToken == "" {

config/auth_azure_msi.go

@@ -8,6 +8,7 @@ import (
 	"net/http"
 	"time"
 
+	"github.com/databricks/databricks-sdk-go/common/environment"
 	"github.com/databricks/databricks-sdk-go/config/credentials"
 	"github.com/databricks/databricks-sdk-go/httpclient"
 	"github.com/databricks/databricks-sdk-go/logger"
@@ -31,6 +32,11 @@ func (c AzureMsiCredentials) Name() string {
 	return "azure-msi"
 }
 
+// Cloud implements [CloudScoped.Cloud].
+func (c AzureMsiCredentials) Cloud() environment.Cloud {
+	return environment.CloudAzure
+}
+
 func (c AzureMsiCredentials) Configure(ctx context.Context, cfg *Config) (credentials.CredentialsProvider, error) {
 	if !cfg.AzureUseMSI || (cfg.AzureResourceID == "" && cfg.ConfigType() == WorkspaceConfig) {
 		return nil, nil

config/auth_default.go

@@ -5,7 +5,6 @@ import (
 	"fmt"
 	"net/http"
 
-	"github.com/databricks/databricks-sdk-go/common/environment"
 	"github.com/databricks/databricks-sdk-go/config/credentials"
 	"github.com/databricks/databricks-sdk-go/logger"
 )
@@ -23,25 +22,13 @@ var ErrCannotConfigureDefault = fmt.Errorf("cannot configure default credentials
 // INTERNAL: This function is not part of the public API and is subject to
 // change. Users are encouraged to use an explicit credentials strategy rather
 // than relying on a custom credentials chain.
-func NewCredentialsChain(strategies ...CredentialsStrategy) *credentialsChain {
+func NewCredentialsChain(strategies ...CredentialsStrategy) CredentialsStrategy {
 	return &credentialsChain{strategies: strategies}
 }
 
 type credentialsChain struct {
 	strategies []CredentialsStrategy
-	// cloudRequirements maps a strategy name to the cloud it requires. When
-	// set, the auto-detect loop skips strategies whose required cloud does not
-	// match the configured host. The map is not consulted when AuthType is
-	// explicitly set — in that case the named strategy is always attempted.
-	cloudRequirements map[string]environment.Cloud
-	name              string
-}
-
-// WithCloudRequirements sets the cloud requirements for the chain and returns
-// the chain for method chaining.
-func (c *credentialsChain) WithCloudRequirements(m map[string]environment.Cloud) *credentialsChain {
-	c.cloudRequirements = m
-	return c
+	name       string
 }
 
 func (c *credentialsChain) Name() string {
@@ -76,9 +63,9 @@ func (c *credentialsChain) Configure(ctx context.Context, cfg *Config) (credenti
 		// In auto-detect mode, skip cloud-specific strategies that don't match
 		// the detected cloud. This prevents Azure strategies from being
 		// attempted silently on GCP hosts and vice-versa.
-		if requiredCloud, ok := c.cloudRequirements[s.Name()]; ok {
-			if cfg.Environment().Cloud != requiredCloud {
-				logger.Debugf(ctx, "Skipping %q: not configured for %s", s.Name(), requiredCloud)
+		if cs, ok := s.(CloudScoped); ok {
+			if cs.Cloud() != cfg.Environment().Cloud {
+				logger.Debugf(ctx, "Skipping %q: requires %s", s.Name(), cs.Cloud())
 				continue
 			}
 		}
@@ -144,18 +131,7 @@ func (c *DefaultCredentials) Configure(ctx context.Context, cfg *Config) (creden
 		// Google strategies.
 		GoogleCredentials{},
 		GoogleDefaultCredentials{},
-	).WithCloudRequirements(map[string]environment.Cloud{
-		// cloudRequirements declares the cloud each strategy requires.
-		// DefaultCredentials uses this to skip cloud-specific strategies in
-		// auto-detect mode when the host cloud does not match. Cloud filtering
-		// is bypassed when AuthType is explicitly set.
-		"github-oidc-azure":   environment.CloudAzure,
-		"azure-msi":           environment.CloudAzure,
-		"azure-client-secret": environment.CloudAzure,
-		"azure-cli":           environment.CloudAzure,
-		"google-credentials":  environment.CloudGCP,
-		"google-id":           environment.CloudGCP,
-	})
+	)
 	cp, err := chain.Configure(ctx, cfg)
 	if err != nil {
 		return nil, err

config/auth_default_test.go

@@ -10,29 +10,27 @@ import (
 	"github.com/databricks/databricks-sdk-go/config/credentials"
 )
 
-// recordingStrategy is a test helper that records whether Configure was called.
-type recordingStrategy struct {
+// cloudScopedStrategy is a test helper that implements both [CredentialsStrategy]
+// and [CloudScoped], recording whether Configure was called.
+type cloudScopedStrategy struct {
 	name   string
 	called bool
+	cloud  environment.Cloud
 }
 
-func (r *recordingStrategy) Name() string { return r.name }
-func (r *recordingStrategy) Configure(_ context.Context, _ *Config) (credentials.CredentialsProvider, error) {
-	r.called = true
+func (s *cloudScopedStrategy) Name() string             { return s.name }
+func (s *cloudScopedStrategy) Cloud() environment.Cloud { return s.cloud }
+func (s *cloudScopedStrategy) Configure(_ context.Context, _ *Config) (credentials.CredentialsProvider, error) {
+	s.called = true
 	return nil, nil
 }
 
 // TestCredentialsChain_CloudFiltering_SkipsOnCloudMismatch verifies that the
 // chain skips a cloud-specific strategy in auto-detect mode when the detected
 // cloud does not match the strategy's required cloud.
 func TestCredentialsChain_CloudFiltering_SkipsOnCloudMismatch(t *testing.T) {
-	azureStrategy := &recordingStrategy{name: "azure-cli"}
-	chain := &credentialsChain{
-		strategies: []CredentialsStrategy{azureStrategy},
-		cloudRequirements: map[string]environment.Cloud{
-			"azure-cli": environment.CloudAzure,
-		},
-	}
+	azureStrategy := &cloudScopedStrategy{name: "azure-cli", cloud: environment.CloudAzure}
+	chain := &credentialsChain{strategies: []CredentialsStrategy{azureStrategy}}
 
 	// GCP host: azure-cli must be skipped in auto-detect mode.
 	cfg := &Config{Host: "https://xyz.gcp.databricks.com/", resolved: true}
@@ -47,13 +45,8 @@ func TestCredentialsChain_CloudFiltering_SkipsOnCloudMismatch(t *testing.T) {
 // the cloud filter is bypassed when AuthType is explicitly set, so that a user
 // can request "azure-cli" even on a GCP host.
 func TestCredentialsChain_CloudFiltering_BypassesOnExplicitAuthType(t *testing.T) {
-	azureStrategy := &recordingStrategy{name: "azure-cli"}
-	chain := &credentialsChain{
-		strategies: []CredentialsStrategy{azureStrategy},
-		cloudRequirements: map[string]environment.Cloud{
-			"azure-cli": environment.CloudAzure,
-		},
-	}
+	azureStrategy := &cloudScopedStrategy{name: "azure-cli", cloud: environment.CloudAzure}
+	chain := &credentialsChain{strategies: []CredentialsStrategy{azureStrategy}}
 
 	// GCP host but auth_type is explicitly set: cloud filter must be bypassed.
 	cfg := &Config{Host: "https://xyz.gcp.databricks.com/", AuthType: "azure-cli", resolved: true}

config/auth_gcp_google_credentials.go

@@ -6,6 +6,7 @@ import (
 	"io/ioutil"
 	"os"
 
+	"github.com/databricks/databricks-sdk-go/common/environment"
 	"github.com/databricks/databricks-sdk-go/config/credentials"
 	"github.com/databricks/databricks-sdk-go/logger"
 	"golang.org/x/oauth2/google"
@@ -20,6 +21,11 @@ func (c GoogleCredentials) Name() string {
 	return "google-credentials"
 }
 
+// Cloud implements [CloudScoped.Cloud].
+func (c GoogleCredentials) Cloud() environment.Cloud {
+	return environment.CloudGCP
+}
+
 func (c GoogleCredentials) Configure(ctx context.Context, cfg *Config) (credentials.CredentialsProvider, error) {
 	if cfg.GoogleCredentials == "" {
 		return nil, nil

config/auth_gcp_google_id.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 
+	"github.com/databricks/databricks-sdk-go/common/environment"
 	"github.com/databricks/databricks-sdk-go/config/credentials"
 	"github.com/databricks/databricks-sdk-go/logger"
 	"golang.org/x/oauth2"
@@ -20,6 +21,11 @@ func (c GoogleDefaultCredentials) Name() string {
 	return "google-id"
 }
 
+// Cloud implements [CloudScoped.Cloud].
+func (c GoogleDefaultCredentials) Cloud() environment.Cloud {
+	return environment.CloudGCP
+}
+
 func (c GoogleDefaultCredentials) Configure(ctx context.Context, cfg *Config) (credentials.CredentialsProvider, error) {
 	if cfg.GoogleServiceAccount == "" {
 		return nil, nil

config/config.go

@@ -34,6 +34,15 @@ type CredentialsStrategy interface {
 	Configure(context.Context, *Config) (credentials.CredentialsProvider, error)
 }
 
+// CloudScoped is an optional interface that a [CredentialsStrategy] can
+// implement to declare which cloud it supports. When implemented, the
+// credentials chain skips this strategy in auto-detect mode if the configured
+// host's cloud does not match. Cloud filtering is bypassed when
+// [Config.AuthType] is explicitly set.
+type CloudScoped interface {
+	Cloud() environment.Cloud
+}
+
 type Loader interface {
 	// Name is human-addressable representation of this config resolver
 	Name() string