feat(M34): dynamic issuer configuration with encrypted config storage

Replace static env-var-based issuer wiring with GUI-driven dynamic
configuration stored encrypted in PostgreSQL. Operators can now
configure, test, enable/disable, and manage issuers from the dashboard
without restarting the server.

Key changes:
- AES-256-GCM encryption for sensitive issuer config at rest (PBKDF2
  key derivation with 100k iterations)
- Dynamic IssuerRegistry with sync.RWMutex replacing static map
- Connector factory pattern (issuerfactory.NewFromConfig) replacing
  140 lines of static wiring in main.go
- Migration 000009: encrypted_config, last_tested_at, test_status,
  source columns on issuers table
- Env var seeding on first boot with ON CONFLICT DO NOTHING
- Registry Rebuild() for atomic map swap after CRUD operations
- Issuer type validation against domain constants on Create
- Audit trail for test connection results
- Conditional seeding for step-ca/OpenSSL (only when env vars set)
- GUI: source badge, connection test status on issuer detail page

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

internal/service/issuer.go

@@ -2,31 +2,54 @@ package service
 
 import (
 	"context"
+	"encoding/json"
 	"fmt"
 	"log/slog"
+	"os"
+	"strings"
 	"time"
 
+	"github.com/shankar0123/certctl/internal/config"
+	"github.com/shankar0123/certctl/internal/connector/issuerfactory"
+	"github.com/shankar0123/certctl/internal/crypto"
 	"github.com/shankar0123/certctl/internal/domain"
 	"github.com/shankar0123/certctl/internal/repository"
 )
 
+// sensitiveKeys are config key substrings that should be redacted in API responses.
+var sensitiveKeys = []string{"password", "secret", "token", "key", "hmac", "private", "credentials"}
+
 // IssuerService provides business logic for certificate issuer management.
 type IssuerService struct {
-	issuerRepo   repository.IssuerRepository
-	auditService *AuditService
+	issuerRepo    repository.IssuerRepository
+	auditService  *AuditService
+	registry      *IssuerRegistry
+	encryptionKey []byte
+	logger        *slog.Logger
 }
 
 // NewIssuerService creates a new issuer service.
 func NewIssuerService(
 	issuerRepo repository.IssuerRepository,
 	auditService *AuditService,
+	registry *IssuerRegistry,
+	encryptionKey []byte,
+	logger *slog.Logger,
 ) *IssuerService {
 	return &IssuerService{
-		issuerRepo:   issuerRepo,
-		auditService: auditService,
+		issuerRepo:    issuerRepo,
+		auditService:  auditService,
+		registry:      registry,
+		encryptionKey: encryptionKey,
+		logger:        logger,
 	}
 }
 
+// GetRegistry returns the dynamic issuer registry.
+func (s *IssuerService) GetRegistry() *IssuerRegistry {
+	return s.registry
+}
+
 // List returns a paginated list of issuers.
 func (s *IssuerService) List(ctx context.Context, page, perPage int) ([]*domain.Issuer, int64, error) {
 	if page < 1 {
@@ -61,49 +84,112 @@ func (s *IssuerService) Get(ctx context.Context, id string) (*domain.Issuer, err
 	return issuer, nil
 }
 
-// Create validates and stores a new issuer.
-func (s *IssuerService) Create(ctx context.Context, issuer *domain.Issuer, actor string) error {
-	if issuer.Name == "" {
+// validIssuerTypes is the set of allowed issuer types for validation.
+var validIssuerTypes = map[domain.IssuerType]bool{
+	domain.IssuerTypeACME:      true,
+	domain.IssuerTypeGenericCA: true,
+	domain.IssuerTypeStepCA:    true,
+	domain.IssuerTypeOpenSSL:   true,
+	domain.IssuerTypeVault:     true,
+	domain.IssuerTypeDigiCert:  true,
+	domain.IssuerTypeSectigo:   true,
+	domain.IssuerTypeGoogleCAS: true,
+}
+
+// isValidIssuerType checks if a type string is a known issuer type.
+func isValidIssuerType(t domain.IssuerType) bool {
+	return validIssuerTypes[t]
+}
+
+// Create validates and stores a new issuer, encrypting sensitive config.
+func (s *IssuerService) Create(ctx context.Context, iss *domain.Issuer, actor string) error {
+	if iss.Name == "" {
 		return fmt.Errorf("issuer name is required")
 	}
+	if !isValidIssuerType(iss.Type) {
+		return fmt.Errorf("unsupported issuer type: %s", iss.Type)
+	}
 
-	if issuer.ID == "" {
-		issuer.ID = generateID("issuer")
+	if iss.ID == "" {
+		iss.ID = generateID("issuer")
 	}
 	now := time.Now()
-	if issuer.CreatedAt.IsZero() {
-		issuer.CreatedAt = now
+	if iss.CreatedAt.IsZero() {
+		iss.CreatedAt = now
 	}
-	if issuer.UpdatedAt.IsZero() {
-		issuer.UpdatedAt = now
+	if iss.UpdatedAt.IsZero() {
+		iss.UpdatedAt = now
 	}
-	if err := s.issuerRepo.Create(ctx, issuer); err != nil {
+	if iss.TestStatus == "" {
+		iss.TestStatus = "untested"
+	}
+	if iss.Source == "" {
+		iss.Source = "database"
+	}
+
+	// Encrypt the full config and store redacted version in config column
+	if len(iss.Config) > 0 {
+		encrypted, _, err := crypto.EncryptIfKeySet([]byte(iss.Config), s.encryptionKey)
+		if err != nil {
+			return fmt.Errorf("failed to encrypt config: %w", err)
+		}
+		iss.EncryptedConfig = encrypted
+		iss.Config = redactConfigJSON(iss.Config)
+	}
+
+	if err := s.issuerRepo.Create(ctx, iss); err != nil {
 		return fmt.Errorf("failed to create issuer: %w", err)
 	}
 
+	// Add to dynamic registry
+	if iss.Enabled {
+		s.rebuildRegistryQuiet(ctx)
+	}
+
 	if s.auditService != nil {
-		if auditErr := s.auditService.RecordEvent(ctx, actor, domain.ActorTypeUser, "create_issuer", "issuer", issuer.ID, nil); auditErr != nil {
-			slog.Error("failed to record audit event", "error", auditErr)
+		if auditErr := s.auditService.RecordEvent(ctx, actor, domain.ActorTypeUser, "create_issuer", "issuer", iss.ID, nil); auditErr != nil {
+			s.logger.Error("failed to record audit event", "error", auditErr)
 		}
 	}
 
 	return nil
 }
 
-// Update modifies an existing issuer.
-func (s *IssuerService) Update(ctx context.Context, id string, issuer *domain.Issuer, actor string) error {
-	if issuer.Name == "" {
+// Update modifies an existing issuer. Handles "********" preservation for sensitive fields.
+func (s *IssuerService) Update(ctx context.Context, id string, iss *domain.Issuer, actor string) error {
+	if iss.Name == "" {
 		return fmt.Errorf("issuer name is required")
 	}
 
-	issuer.ID = id
-	if err := s.issuerRepo.Update(ctx, issuer); err != nil {
+	iss.ID = id
+	iss.UpdatedAt = time.Now()
+
+	// If config contains "********" values, merge with existing decrypted config
+	if len(iss.Config) > 0 {
+		mergedConfig, err := s.mergeRedactedConfig(ctx, id, iss.Config)
+		if err != nil {
+			return fmt.Errorf("failed to merge config: %w", err)
+		}
+
+		// Encrypt the merged config
+		encrypted, _, encErr := crypto.EncryptIfKeySet(mergedConfig, s.encryptionKey)
+		if encErr != nil {
+			return fmt.Errorf("failed to encrypt config: %w", encErr)
+		}
+		iss.EncryptedConfig = encrypted
+		iss.Config = redactConfigJSON(json.RawMessage(mergedConfig))
+	}
+
+	if err := s.issuerRepo.Update(ctx, iss); err != nil {
 		return fmt.Errorf("failed to update issuer %s: %w", id, err)
 	}
 
+	// Rebuild registry after update
+	s.rebuildRegistryQuiet(ctx)
+
 	if s.auditService != nil {
 		if auditErr := s.auditService.RecordEvent(ctx, actor, domain.ActorTypeUser, "update_issuer", "issuer", id, nil); auditErr != nil {
-			slog.Error("failed to record audit event", "error", auditErr)
+			s.logger.Error("failed to record audit event", "error", auditErr)
 		}
 	}
 
@@ -116,27 +202,48 @@ func (s *IssuerService) Delete(ctx context.Context, id string, actor string) err
 		return fmt.Errorf("failed to delete issuer %s: %w", id, err)
 	}
 
+	// Remove from registry
+	if s.registry != nil {
+		s.registry.Remove(id)
+	}
+
 	if s.auditService != nil {
 		if auditErr := s.auditService.RecordEvent(ctx, actor, domain.ActorTypeUser, "delete_issuer", "issuer", id, nil); auditErr != nil {
-			slog.Error("failed to record audit event", "error", auditErr)
+			s.logger.Error("failed to record audit event", "error", auditErr)
 		}
 	}
 
 	return nil
 }
 
-// TestConnectionWithContext verifies the issuer connection with context.
+// TestConnectionWithContext tests the connection to an issuer by instantiating a throwaway
+// connector and calling ValidateConfig. Records the result in the database.
 func (s *IssuerService) TestConnectionWithContext(ctx context.Context, id string) error {
-	issuer, err := s.issuerRepo.Get(ctx, id)
+	iss, err := s.issuerRepo.Get(ctx, id)
 	if err != nil {
 		return fmt.Errorf("issuer not found: %w", err)
 	}
 
-	// TODO: Implement actual connection test based on issuer type
-	if issuer == nil {
-		return fmt.Errorf("issuer not found")
+	// Get the decrypted config
+	configJSON, err := s.getDecryptedConfig(iss)
+	if err != nil {
+		s.updateTestStatus(ctx, iss, "failed")
+		return fmt.Errorf("failed to decrypt config: %w", err)
 	}
 
+	// Instantiate a throwaway connector and validate
+	connector, err := issuerfactory.NewFromConfig(string(iss.Type), configJSON, s.logger)
+	if err != nil {
+		s.updateTestStatus(ctx, iss, "failed")
+		return fmt.Errorf("failed to create connector: %w", err)
+	}
+
+	if err := connector.ValidateConfig(ctx, configJSON); err != nil {
+		s.updateTestStatus(ctx, iss, "failed")
+		return fmt.Errorf("connection test failed: %w", err)
+	}
+
+	s.updateTestStatus(ctx, iss, "success")
 	return nil
 }
 
@@ -145,6 +252,241 @@ func (s *IssuerService) TestConnection(id string) error {
 	return s.TestConnectionWithContext(context.Background(), id)
 }
 
+// BuildRegistry loads all enabled issuers from the database and rebuilds the dynamic registry.
+// Called at server startup. Partial failures (individual issuers failing to load) are logged
+// as warnings but don't prevent the server from starting.
+func (s *IssuerService) BuildRegistry(ctx context.Context) error {
+	issuers, err := s.issuerRepo.List(ctx)
+	if err != nil {
+		return fmt.Errorf("failed to load issuers from database: %w", err)
+	}
+
+	if err := s.registry.Rebuild(issuers, s.encryptionKey); err != nil {
+		// Log the error but don't fail — some issuers loaded successfully.
+		s.logger.Warn("issuer registry rebuilt with errors", "error", err)
+	}
+
+	s.logger.Info("issuer registry built from database", "total_issuers", len(issuers), "registry_size", s.registry.Len())
+	return nil
+}
+
+// SeedFromEnvVars creates issuer records from environment variables if the database is empty.
+// Uses ON CONFLICT DO NOTHING so GUI-created configs are never overwritten.
+func (s *IssuerService) SeedFromEnvVars(ctx context.Context, cfg *config.Config) {
+	// Check if any issuers already exist
+	existing, err := s.issuerRepo.List(ctx)
+	if err != nil {
+		s.logger.Error("failed to check existing issuers for env var seeding", "error", err)
+		return
+	}
+
+	if len(existing) > 0 {
+		s.logger.Info("issuers already exist in database, skipping env var seeding", "count", len(existing))
+		return
+	}
+
+	s.logger.Info("no issuers in database, seeding from environment variables")
+
+	seeds := s.buildEnvVarSeeds(cfg)
+	seeded := 0
+	for _, seed := range seeds {
+		// Encrypt the config if key is set
+		if len(seed.Config) > 0 {
+			encrypted, _, encErr := crypto.EncryptIfKeySet([]byte(seed.Config), s.encryptionKey)
+			if encErr != nil {
+				s.logger.Error("failed to encrypt seed config", "id", seed.ID, "error", encErr)
+				continue
+			}
+			seed.EncryptedConfig = encrypted
+			seed.Config = redactConfigJSON(seed.Config)
+		}
+
+		if err := s.issuerRepo.Create(ctx, seed); err != nil {
+			s.logger.Warn("failed to seed issuer from env var", "id", seed.ID, "error", err)
+			continue
+		}
+		seeded++
+		s.logger.Info("seeded issuer from env vars", "id", seed.ID, "type", seed.Type)
+	}
+
+	s.logger.Info("env var seeding complete", "seeded", seeded, "total_seeds", len(seeds))
+}
+
+// buildEnvVarSeeds constructs issuer domain objects from the config's env var values.
+func (s *IssuerService) buildEnvVarSeeds(cfg *config.Config) []*domain.Issuer {
+	now := time.Now()
+	var seeds []*domain.Issuer
+
+	// Local CA (always seeded)
+	seeds = append(seeds, &domain.Issuer{
+		ID:        "iss-local",
+		Name:      "Local CA",
+		Type:      domain.IssuerTypeGenericCA,
+		Config:    mustJSON(map[string]interface{}{"ca_cert_path": cfg.CA.CertPath, "ca_key_path": cfg.CA.KeyPath}),
+		Enabled:   true,
+		Source:    "env",
+		CreatedAt: now,
+		UpdatedAt: now,
+	})
+
+	// ACME (always seeded — even with empty directory URL, for demo mode)
+	seeds = append(seeds, &domain.Issuer{
+		ID:   "iss-acme-staging",
+		Name: "ACME Staging",
+		Type: domain.IssuerTypeACME,
+		Config: mustJSON(map[string]interface{}{
+			"directory_url":  cfg.ACME.DirectoryURL,
+			"email":          cfg.ACME.Email,
+			"challenge_type": cfg.ACME.ChallengeType,
+			"insecure":       cfg.ACME.Insecure,
+			"ari_enabled":    cfg.ACME.ARIEnabled,
+		}),
+		Enabled:   true,
+		Source:    "env",
+		CreatedAt: now,
+		UpdatedAt: now,
+	})
+
+	// ACME prod (same config, different ID for backward compat)
+	seeds = append(seeds, &domain.Issuer{
+		ID:   "iss-acme-prod",
+		Name: "ACME Production",
+		Type: domain.IssuerTypeACME,
+		Config: mustJSON(map[string]interface{}{
+			"directory_url":  cfg.ACME.DirectoryURL,
+			"email":          cfg.ACME.Email,
+			"challenge_type": cfg.ACME.ChallengeType,
+			"insecure":       cfg.ACME.Insecure,
+			"ari_enabled":    cfg.ACME.ARIEnabled,
+		}),
+		Enabled:   true,
+		Source:    "env",
+		CreatedAt: now,
+		UpdatedAt: now,
+	})
+
+	// Conditional: step-ca — only seed if CERTCTL_STEPCA_URL is set
+	if stepcaURL := getEnvForSeed("CERTCTL_STEPCA_URL"); stepcaURL != "" {
+		seeds = append(seeds, &domain.Issuer{
+			ID:   "iss-stepca",
+			Name: "step-ca",
+			Type: domain.IssuerTypeStepCA,
+			Config: mustJSON(map[string]interface{}{
+				"ca_url":               stepcaURL,
+				"root_cert_path":       getEnvForSeed("CERTCTL_STEPCA_ROOT_CERT"),
+				"provisioner_name":     getEnvForSeed("CERTCTL_STEPCA_PROVISIONER"),
+				"provisioner_key_path": getEnvForSeed("CERTCTL_STEPCA_KEY_PATH"),
+				"provisioner_password": getEnvForSeed("CERTCTL_STEPCA_PASSWORD"),
+			}),
+			Enabled:   true,
+			Source:    "env",
+			CreatedAt: now,
+			UpdatedAt: now,
+		})
+	}
+
+	// Conditional: OpenSSL — only seed if sign script is set
+	if signScript := getEnvForSeed("CERTCTL_OPENSSL_SIGN_SCRIPT"); signScript != "" {
+		seeds = append(seeds, &domain.Issuer{
+			ID:   "iss-openssl",
+			Name: "OpenSSL/Custom CA",
+			Type: domain.IssuerTypeOpenSSL,
+			Config: mustJSON(map[string]interface{}{
+				"sign_script":   signScript,
+				"revoke_script": getEnvForSeed("CERTCTL_OPENSSL_REVOKE_SCRIPT"),
+				"crl_script":    getEnvForSeed("CERTCTL_OPENSSL_CRL_SCRIPT"),
+			}),
+			Enabled:   true,
+			Source:    "env",
+			CreatedAt: now,
+			UpdatedAt: now,
+		})
+	}
+
+	// Conditional: Vault PKI
+	if cfg.Vault.Addr != "" {
+		seeds = append(seeds, &domain.Issuer{
+			ID:   "iss-vault",
+			Name: "Vault PKI",
+			Type: domain.IssuerTypeVault,
+			Config: mustJSON(map[string]interface{}{
+				"addr":  cfg.Vault.Addr,
+				"token": cfg.Vault.Token,
+				"mount": cfg.Vault.Mount,
+				"role":  cfg.Vault.Role,
+				"ttl":   cfg.Vault.TTL,
+			}),
+			Enabled:   true,
+			Source:    "env",
+			CreatedAt: now,
+			UpdatedAt: now,
+		})
+	}
+
+	// Conditional: DigiCert
+	if cfg.DigiCert.APIKey != "" {
+		seeds = append(seeds, &domain.Issuer{
+			ID:   "iss-digicert",
+			Name: "DigiCert CertCentral",
+			Type: domain.IssuerTypeDigiCert,
+			Config: mustJSON(map[string]interface{}{
+				"api_key":      cfg.DigiCert.APIKey,
+				"org_id":       cfg.DigiCert.OrgID,
+				"product_type": cfg.DigiCert.ProductType,
+				"base_url":     cfg.DigiCert.BaseURL,
+			}),
+			Enabled:   true,
+			Source:    "env",
+			CreatedAt: now,
+			UpdatedAt: now,
+		})
+	}
+
+	// Conditional: Sectigo
+	if cfg.Sectigo.CustomerURI != "" && cfg.Sectigo.Login != "" && cfg.Sectigo.Password != "" {
+		seeds = append(seeds, &domain.Issuer{
+			ID:   "iss-sectigo",
+			Name: "Sectigo SCM",
+			Type: domain.IssuerTypeSectigo,
+			Config: mustJSON(map[string]interface{}{
+				"customer_uri": cfg.Sectigo.CustomerURI,
+				"login":        cfg.Sectigo.Login,
+				"password":     cfg.Sectigo.Password,
+				"org_id":       cfg.Sectigo.OrgID,
+				"cert_type":    cfg.Sectigo.CertType,
+				"term":         cfg.Sectigo.Term,
+				"base_url":     cfg.Sectigo.BaseURL,
+			}),
+			Enabled:   true,
+			Source:    "env",
+			CreatedAt: now,
+			UpdatedAt: now,
+		})
+	}
+
+	// Conditional: Google CAS
+	if cfg.GoogleCAS.Project != "" && cfg.GoogleCAS.Credentials != "" {
+		seeds = append(seeds, &domain.Issuer{
+			ID:   "iss-googlecas",
+			Name: "Google CAS",
+			Type: domain.IssuerTypeGoogleCAS,
+			Config: mustJSON(map[string]interface{}{
+				"project":     cfg.GoogleCAS.Project,
+				"location":    cfg.GoogleCAS.Location,
+				"ca_pool":     cfg.GoogleCAS.CAPool,
+				"credentials": cfg.GoogleCAS.Credentials,
+				"ttl":         cfg.GoogleCAS.TTL,
+			}),
+			Enabled:   true,
+			Source:    "env",
+			CreatedAt: now,
+			UpdatedAt: now,
+		})
+	}
+
+	return seeds
+}
+
 // ListIssuers returns paginated issuers (handler interface method).
 func (s *IssuerService) ListIssuers(page, perPage int) ([]domain.Issuer, int64, error) {
 	if page < 1 {
@@ -176,33 +518,234 @@ func (s *IssuerService) GetIssuer(id string) (*domain.Issuer, error) {
 }
 
 // CreateIssuer creates a new issuer (handler interface method).
-func (s *IssuerService) CreateIssuer(issuer domain.Issuer) (*domain.Issuer, error) {
-	if issuer.ID == "" {
-		issuer.ID = generateID("issuer")
+func (s *IssuerService) CreateIssuer(iss domain.Issuer) (*domain.Issuer, error) {
+	if !isValidIssuerType(iss.Type) {
+		return nil, fmt.Errorf("unsupported issuer type: %s", iss.Type)
+	}
+	if iss.ID == "" {
+		iss.ID = generateID("issuer")
 	}
 	now := time.Now()
-	if issuer.CreatedAt.IsZero() {
-		issuer.CreatedAt = now
+	if iss.CreatedAt.IsZero() {
+		iss.CreatedAt = now
 	}
-	if issuer.UpdatedAt.IsZero() {
-		issuer.UpdatedAt = now
+	if iss.UpdatedAt.IsZero() {
+		iss.UpdatedAt = now
 	}
-	if err := s.issuerRepo.Create(context.Background(), &issuer); err != nil {
+	if iss.TestStatus == "" {
+		iss.TestStatus = "untested"
+	}
+	if iss.Source == "" {
+		iss.Source = "database"
+	}
+
+	// Encrypt config
+	if len(iss.Config) > 0 {
+		encrypted, _, err := crypto.EncryptIfKeySet([]byte(iss.Config), s.encryptionKey)
+		if err != nil {
+			return nil, fmt.Errorf("failed to encrypt config: %w", err)
+		}
+		iss.EncryptedConfig = encrypted
+		iss.Config = redactConfigJSON(iss.Config)
+	}
+
+	if err := s.issuerRepo.Create(context.Background(), &iss); err != nil {
 		return nil, fmt.Errorf("failed to create issuer: %w", err)
 	}
-	return &issuer, nil
+
+	// Rebuild registry
+	if iss.Enabled {
+		s.rebuildRegistryQuiet(context.Background())
+	}
+
+	return &iss, nil
 }
 
 // UpdateIssuer modifies an issuer (handler interface method).
-func (s *IssuerService) UpdateIssuer(id string, issuer domain.Issuer) (*domain.Issuer, error) {
-	issuer.ID = id
-	if err := s.issuerRepo.Update(context.Background(), &issuer); err != nil {
+func (s *IssuerService) UpdateIssuer(id string, iss domain.Issuer) (*domain.Issuer, error) {
+	iss.ID = id
+	iss.UpdatedAt = time.Now()
+
+	// Merge redacted fields with existing config
+	if len(iss.Config) > 0 {
+		mergedConfig, err := s.mergeRedactedConfig(context.Background(), id, iss.Config)
+		if err != nil {
+			return nil, fmt.Errorf("failed to merge config: %w", err)
+		}
+
+		encrypted, _, encErr := crypto.EncryptIfKeySet(mergedConfig, s.encryptionKey)
+		if encErr != nil {
+			return nil, fmt.Errorf("failed to encrypt config: %w", encErr)
+		}
+		iss.EncryptedConfig = encrypted
+		iss.Config = redactConfigJSON(json.RawMessage(mergedConfig))
+	}
+
+	if err := s.issuerRepo.Update(context.Background(), &iss); err != nil {
 		return nil, fmt.Errorf("failed to update issuer: %w", err)
 	}
-	return &issuer, nil
+
+	s.rebuildRegistryQuiet(context.Background())
+
+	return &iss, nil
 }
 
 // DeleteIssuer removes an issuer (handler interface method).
 func (s *IssuerService) DeleteIssuer(id string) error {
-	return s.issuerRepo.Delete(context.Background(), id)
+	if err := s.issuerRepo.Delete(context.Background(), id); err != nil {
+		return err
+	}
+	if s.registry != nil {
+		s.registry.Remove(id)
+	}
+	return nil
+}
+
+// --- Internal helpers ---
+
+// rebuildRegistryQuiet rebuilds the registry, logging errors instead of returning them.
+func (s *IssuerService) rebuildRegistryQuiet(ctx context.Context) {
+	if s.registry == nil {
+		return
+	}
+	if err := s.BuildRegistry(ctx); err != nil {
+		s.logger.Error("failed to rebuild issuer registry after change", "error", err)
+	}
+}
+
+// getDecryptedConfig returns the decrypted config JSON for an issuer.
+func (s *IssuerService) getDecryptedConfig(iss *domain.Issuer) (json.RawMessage, error) {
+	if len(iss.EncryptedConfig) > 0 {
+		decrypted, err := crypto.DecryptIfKeySet(iss.EncryptedConfig, s.encryptionKey)
+		if err != nil {
+			return nil, err
+		}
+		return json.RawMessage(decrypted), nil
+	}
+	if len(iss.Config) > 0 {
+		return iss.Config, nil
+	}
+	return json.RawMessage("{}"), nil
+}
+
+// mergeRedactedConfig merges incoming config (which may have "********" values)
+// with the existing decrypted config so sensitive fields are preserved.
+func (s *IssuerService) mergeRedactedConfig(ctx context.Context, id string, incoming json.RawMessage) ([]byte, error) {
+	// Parse incoming config
+	var incomingMap map[string]interface{}
+	if err := json.Unmarshal(incoming, &incomingMap); err != nil {
+		s.logger.Warn("mergeRedactedConfig: incoming config is not a JSON object, using as-is", "issuer", id, "error", err)
+		return incoming, nil
+	}
+
+	// Check if any values are "********"
+	hasRedacted := false
+	for _, v := range incomingMap {
+		if str, ok := v.(string); ok && str == "********" {
+			hasRedacted = true
+			break
+		}
+	}
+
+	if !hasRedacted {
+		return incoming, nil // No redacted values, use incoming as-is
+	}
+
+	// Load existing config to get real values
+	existing, err := s.issuerRepo.Get(ctx, id)
+	if err != nil {
+		s.logger.Warn("mergeRedactedConfig: could not load existing issuer, redacted values will be lost", "issuer", id, "error", err)
+		return incoming, nil
+	}
+
+	existingConfig, err := s.getDecryptedConfig(existing)
+	if err != nil {
+		s.logger.Warn("mergeRedactedConfig: could not decrypt existing config, redacted values will be lost", "issuer", id, "error", err)
+		return incoming, nil
+	}
+
+	var existingMap map[string]interface{}
+	if err := json.Unmarshal(existingConfig, &existingMap); err != nil {
+		s.logger.Warn("mergeRedactedConfig: existing config is not a JSON object, redacted values will be lost", "issuer", id, "error", err)
+		return incoming, nil
+	}
+
+	// Merge: for each "********" value in incoming, use existing value
+	for k, v := range incomingMap {
+		if str, ok := v.(string); ok && str == "********" {
+			if existingVal, exists := existingMap[k]; exists {
+				incomingMap[k] = existingVal
+			}
+		}
+	}
+
+	return json.Marshal(incomingMap)
+}
+
+// updateTestStatus updates the test_status and last_tested_at fields in the database
+// and records an audit event.
+func (s *IssuerService) updateTestStatus(ctx context.Context, iss *domain.Issuer, status string) {
+	now := time.Now()
+	iss.TestStatus = status
+	iss.LastTestedAt = &now
+	iss.UpdatedAt = now
+	if err := s.issuerRepo.Update(ctx, iss); err != nil {
+		s.logger.Error("failed to update test status", "issuer", iss.ID, "status", status, "error", err)
+	}
+
+	// Record audit event for connection test
+	if s.auditService != nil {
+		action := "issuer_test_connection_" + status
+		details := map[string]interface{}{"issuer_type": string(iss.Type), "result": status}
+		if auditErr := s.auditService.RecordEvent(ctx, "system", domain.ActorTypeSystem, action, "issuer", iss.ID, details); auditErr != nil {
+			s.logger.Error("failed to record test connection audit event", "error", auditErr)
+		}
+	}
+}
+
+// redactConfigJSON replaces sensitive values in a JSON config with "********".
+func redactConfigJSON(configJSON json.RawMessage) json.RawMessage {
+	var m map[string]interface{}
+	if err := json.Unmarshal(configJSON, &m); err != nil {
+		return configJSON // Not a JSON object, return as-is
+	}
+
+	for k, v := range m {
+		if isSensitiveConfigKey(k) {
+			if str, ok := v.(string); ok && str != "" {
+				m[k] = "********"
+			}
+		}
+	}
+
+	redacted, err := json.Marshal(m)
+	if err != nil {
+		return configJSON
+	}
+	return json.RawMessage(redacted)
+}
+
+// isSensitiveConfigKey checks if a config key contains sensitive substrings.
+func isSensitiveConfigKey(key string) bool {
+	lower := strings.ToLower(key)
+	for _, s := range sensitiveKeys {
+		if strings.Contains(lower, s) {
+			return true
+		}
+	}
+	return false
+}
+
+// getEnvForSeed reads an environment variable for seed data construction.
+func getEnvForSeed(key string) string {
+	return os.Getenv(key)
+}
+
+// mustJSON marshals a value to json.RawMessage, panicking on error (for seed data only).
+func mustJSON(v interface{}) json.RawMessage {
+	b, err := json.Marshal(v)
+	if err != nil {
+		panic(fmt.Sprintf("mustJSON: %v", err))
+	}
+	return json.RawMessage(b)
 }