fix: modify credential refresh to support stacked contexts (#856)

Signed-off-by: Grant Linville <grant@acorn.io>

Author: g-linville

pkg/credentials/noop.go

@@ -12,6 +12,10 @@ func (s NoopStore) Add(context.Context, Credential) error {
 	return nil
 }
 
+func (s NoopStore) Refresh(context.Context, Credential) error {
+	return nil
+}
+
 func (s NoopStore) Remove(context.Context, string) error {
 	return nil
 }

pkg/credentials/store.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"path/filepath"
 	"regexp"
+	"slices"
 	"strings"
 
 	"github.com/docker/cli/cli/config/credentials"
@@ -26,6 +27,7 @@ type CredentialBuilder interface {
 type CredentialStore interface {
 	Get(ctx context.Context, toolName string) (*Credential, bool, error)
 	Add(ctx context.Context, cred Credential) error
+	Refresh(ctx context.Context, cred Credential) error
 	Remove(ctx context.Context, toolName string) error
 	List(ctx context.Context) ([]Credential, error)
 }
@@ -95,6 +97,8 @@ func (s Store) Get(ctx context.Context, toolName string) (*Credential, bool, err
 	return &cred, true, nil
 }
 
+// Add adds a new credential to the credential store.
+// Any context set on the credential object will be overwritten with the first context of the credential store.
 func (s Store) Add(ctx context.Context, cred Credential) error {
 	first := first(s.credCtxs)
 	if first == AllCredentialContexts {
@@ -113,6 +117,23 @@ func (s Store) Add(ctx context.Context, cred Credential) error {
 	return store.Store(auth)
 }
 
+// Refresh updates an existing credential in the credential store.
+func (s Store) Refresh(ctx context.Context, cred Credential) error {
+	if !slices.Contains(s.credCtxs, cred.Context) {
+		return fmt.Errorf("context %q not in list of valid contexts for this credential store", cred.Context)
+	}
+
+	store, err := s.getStore(ctx)
+	if err != nil {
+		return err
+	}
+	auth, err := cred.toDockerAuthConfig()
+	if err != nil {
+		return err
+	}
+	return store.Store(auth)
+}
+
 func (s Store) Remove(ctx context.Context, toolName string) error {
 	first := first(s.credCtxs)
 	if len(s.credCtxs) > 1 || first == AllCredentialContexts {

pkg/runner/runner.go

@@ -854,8 +854,10 @@ func (r *Runner) handleCredentials(callCtx engine.Context, monitor Monitor, env
 		}
 
 		var (
-			c      *credentials.Credential
-			exists bool
+			c                *credentials.Credential
+			resultCredential credentials.Credential
+			exists           bool
+			refresh          bool
 		)
 
 		rm := runtimeWithLogger(callCtx, monitor, r.runtimeManager)
@@ -886,6 +888,7 @@ func (r *Runner) handleCredentials(callCtx engine.Context, monitor Monitor, env
 		if !exists || c.IsExpired() {
 			// If the existing credential is expired, we need to provide it to the cred tool through the environment.
 			if exists && c.IsExpired() {
+				refresh = true
 				credJSON, err := json.Marshal(c)
 				if err != nil {
 					return nil, fmt.Errorf("failed to marshal credential: %w", err)
@@ -916,39 +919,56 @@ func (r *Runner) handleCredentials(callCtx engine.Context, monitor Monitor, env
 				continue
 			}
 
-			if err := json.Unmarshal([]byte(*res.Result), &c); err != nil {
+			if err := json.Unmarshal([]byte(*res.Result), &resultCredential); err != nil {
 				return nil, fmt.Errorf("failed to unmarshal credential tool %s response: %w", ref.Reference, err)
 			}
-			c.ToolName = credName
-			c.Type = credentials.CredentialTypeTool
+			resultCredential.ToolName = credName
+			resultCredential.Type = credentials.CredentialTypeTool
+
+			if refresh {
+				// If this is a credential refresh, we need to make sure we use the same context.
+				resultCredential.Context = c.Context
+			} else {
+				// If it is a new credential, let the credential store determine the context.
+				resultCredential.Context = ""
+			}
 
 			isEmpty := true
-			for _, v := range c.Env {
+			for _, v := range resultCredential.Env {
 				if v != "" {
 					isEmpty = false
 					break
 				}
 			}
 
-			if !c.Ephemeral {
+			if !resultCredential.Ephemeral {
 				// Only store the credential if the tool is on GitHub or has an alias, and the credential is non-empty.
 				if (isGitHubTool(toolName) && callCtx.Program.ToolSet[ref.ToolID].Source.Repo != nil) || credentialAlias != "" {
 					if isEmpty {
 						log.Warnf("Not saving empty credential for tool %s", toolName)
-					} else if err := r.credStore.Add(callCtx.Ctx, *c); err != nil {
-						return nil, fmt.Errorf("failed to add credential for tool %s: %w", toolName, err)
+					} else {
+						if refresh {
+							err = r.credStore.Refresh(callCtx.Ctx, resultCredential)
+						} else {
+							err = r.credStore.Add(callCtx.Ctx, resultCredential)
+						}
+						if err != nil {
+							return nil, fmt.Errorf("failed to save credential for tool %s: %w", toolName, err)
+						}
 					}
 				} else {
 					log.Warnf("Not saving credential for tool %s - credentials will only be saved for tools from GitHub, or tools that use aliases.", toolName)
 				}
 			}
+		} else {
+			resultCredential = *c
 		}
 
-		if c.ExpiresAt != nil && (nearestExpiration == nil || nearestExpiration.After(*c.ExpiresAt)) {
-			nearestExpiration = c.ExpiresAt
+		if resultCredential.ExpiresAt != nil && (nearestExpiration == nil || nearestExpiration.After(*resultCredential.ExpiresAt)) {
+			nearestExpiration = resultCredential.ExpiresAt
 		}
 
-		for k, v := range c.Env {
+		for k, v := range resultCredential.Env {
 			env = append(env, fmt.Sprintf("%s=%s", k, v))
 		}
 	}