Fix DSN construction to support passwords with special characters#593
Merged
morgo merged 6 commits intoblock:mainfrom Mar 2, 2026
Merged
Fix DSN construction to support passwords with special characters#593morgo merged 6 commits intoblock:mainfrom
morgo merged 6 commits intoblock:mainfrom
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Replace fmt.Sprintf-based DSN construction with mysql.Config.FormatDSN() in Runner.dsn(), and rewrite newDSN() to set parameters on the parsed config struct instead of naive string concatenation. The old approach used strings.Contains(dsn, "?") to detect query params, which broke when passwords contained "?" (e.g. AWS IAM auth tokens), causing all session variables and driver options to be absorbed into the DB name. Also enable AllowCleartextPasswords, which is required for AWS RDS IAM authentication (mysql_clear_password plugin).
Remove redundant TLS parameter pre-checks that were bypassing DSN construction. Remove unused createFallbackDSN function. Make AllowCleartextPasswords conditional on TLS being configured rather than always enabled. Update tests for corrected mixed-case TLS parameter behavior and add special character password round-trip tests.
Empty tls= is indistinguishable from unset after ParseDSN, so the TLS config should be applied rather than preserving the empty value. Remove allowNativePasswords=true from expected params since true is the go-mysql-driver default and FormatDSN() omits default values.
…n newDSN - newDSN: replace early return when TLS is set with a guard around only the TLS switch block, so session variables (sql_mode, time_zone, innodb_lock_wait_timeout, RejectReadOnly, etc.) are always applied - addTLSParametersToDSN: check cfg.TLSConfig before overwriting to preserve user-supplied TLS overrides (e.g. tls=skip-verify) - Update tests to verify TLS preservation via parsed config rather than raw string equality Amp-Thread-ID: https://ampcode.com/threads/T-019c63df-40f9-740b-8419-c3aa7d83cb32 Co-authored-by: Amp <amp@ampcode.com>
Kiran01bm
reviewed
Feb 16, 2026
Resolve conflicts in pkg/dbconn/conn.go and pkg/migration/runner_test.go: - conn.go: Keep PR's cfg.TLSConfig/cfg.FormatDSN() approach (safe for special characters in passwords) with main's switch statement structure - runner_test.go: Keep both TestDSN (from PR) and TestEnumReorder/ TestSetReorder (from main)
…ve mixed-case TLS test wording - Remove cfg.AllowNativePasswords = true since it is the default in go-sql-driver (https://github.com/go-sql-driver/mysql/blob/v1.9.3/dsn.go#L96) - Improve test description for mixed-case TLS parameter edge case to explicitly call out that uppercase 'TLS' is ignored by ParseDSN and passed through as an unknown query parameter - Remove stale comment referencing AllowNativePasswords in fallback test
morgo
approved these changes
Mar 2, 2026
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Summary
Fixes #592
fmt.Sprintfand manual string concatenation breaks when passwords contain special characters (@,?,&,/) — common in AWS IAM authentication tokensnewDSN()inpkg/dbconn/conn.goanddsn()inpkg/migration/runner.goto use thego-sql-driver/mysqllibrary's structuredConfigtype withParseDSN()/FormatDSN()instead of manual string building@,?,&, and full AWS IAM-style tokens to verify correct round-trippingTest plan
@, multiple@, mixed special chars, empty password, AWS IAM-style token)go test ./pkg/dbconn/... ./pkg/migration/...)🤖 Generated with Claude Code