no primary database specified in the configuration

Error message

no primary database specified in the configuration

What it means

This error is returned by selectDBMS in the engine session setup when, after evaluating all configured databases, no primary database was selected. The session tracks its chosen database via s.dbtype and s.dsn; if either is empty, no usable connection string could be built. The library throws it because it cannot initialize an asset store (assetdb.New) without a database type and DSN.

Source

Thrown at engine/sessions/session.go:261

			case "neo4+s":
				fallthrough
			case "neo4j+sec":
				fallthrough
			case "bolt":
				fallthrough
			case "bolt+s":
				fallthrough
			case "bolt+sec":
				s.dsn = db.URL
				s.dbtype = neo4j.Neo4j
			}
			// Break the loop once the primary database is found.
			break
		}
	}
	// Check if a valid database connection string was generated.
	if s.dsn == "" || s.dbtype == "" {
		return errors.New("no primary database specified in the configuration")
	}
	// Initialize the database store
	store, err := assetdb.New(s.dbtype, s.dsn)
	if err != nil {
		return errors.New("failed to initialize database store: " + err.Error())
	}
	s.db = store
	return nil
}

func (s *Session) createTemporaryDir() (string, error) {
	outdir := config.OutputDirectory()
	if outdir == "" {
		return "", errors.New("failed to obtain the output directory")
	}

	dir, err := os.MkdirTemp(outdir, "session-"+s.ID().String())
	if err != nil {

View on GitHub (pinned to 79299dce87)

Solutions

Add or restore a database entry flagged as primary in the session configuration (e.g. sqlite/postgres) so selectDBMS assigns s.dbtype and s.dsn
Verify the config file actually loaded — check for wrong --config path or empty config struct before session creation
Confirm the primary flag key spelling matches what the loader expects (e.g. 'primary: true')
Log the parsed database configuration before setupDB to confirm entries are visible to the session

Example fix

// before (no database in config)
{
  "databases": []
}
// after
{
  "databases": [
    { "type": "sqlite", "path": "./assets.db", "primary": true }
  ]
}

Defensive patterns

Strategy: validation

Validate before calling

if len(cfg.Databases) == 0 || !hasPrimary(cfg.Databases) {
    return errors.New("configuration must define a primary database before creating a session")
}

func hasPrimary(dbs []Database) bool {
    for _, d := range dbs {
        if d.Primary {
            return true
        }
    }
    return false
}

Prevention

Always define exactly one primary database entry in the session config
Validate the config schema at startup, before any session is created
Add a smoke test that builds a session from the shipped default config
Keep the primary flag key consistent with the loader's expected field name

When it happens

Trigger: Calling CreateSession/setupDB when the configuration contains no database entries at all, or every entry lacks the 'primary' flag so the loop never assigns s.dbtype/s.dsn.

Common situations: Fresh installs where the config file was not fully filled in; users commenting out or deleting the primary database block; config files with only read-replica or secondary database entries; typos in the primary flag key so it is never recognized.

Understand the failure class

Background: "is required", "must be set", "missing required field": configuration validation errors across open-source libraries — this error's family across 36 libraries.

Related errors

AI-assisted analysis of owasp-amass/amass@79299dce87 (2026-09-06). Data as JSON: /api/errors/5db53dbf5ac8668e. Report an issue: GitHub.