direct_pay_core 0.0.1

Core payment engine for Direct Pay (S2S) — server-to-server payment SDK for Flutter with SHA-512 hashing, 3D Secure WebView, and structured logging.

Changelog

0.0.1

• Initial release of the core payment engine.
• Server-to-server payment initiation via Dio HTTP client.
• Configurable hash algorithm: SHA-512 (default) and SHA-256.
• Sorted key-value hash generation with constant-time response verification.
• 3D Secure challenge flow via in-app WebView.
• Configurable SDK setup: appId, merchantKey, baseUrl, optional returnUrl.
• HTTPS enforcement with runtime validation.
• Input validation: Luhn check, CVV/expiry format, email, amount.
• Sensitive data masking in debug logs (card number, CVV, expiry, hash).
• Debug-only structured logging via DirectPayLogger.
• WebView hardened: non-HTTPS schemes blocked, permissions denied, file access disabled.
• merchantKey marked @internal — not exposed to host apps.
• Clean architecture: config, data, domain, and presentation layers.