The variable ErrNonTLSConnection has been simplified from a multi-line declaration to a single-line declaration. This increases code readability and maintains consistency with Go conventions.
Introduce a global error variable for non-TLS connections and update corresponding error handling across the codebase. This enhances readability and maintainability of the error management logic.
Implemented tests for various SCRAM-SHA authentication methods including SCRAM-SHA-1, SCRAM-SHA-1-PLUS, SCRAM-SHA-256, and SCRAM-SHA-256-PLUS with invalid credentials. This ensures that the client correctly handles and reports authentication failures.
Corrects the error messages returned for unsupported SMTP authentication types from ErrXOauth2AuthNotSupported to specific errors like ErrSCRAMSHA1AuthNotSupported, ErrSCRAMSHA256AuthNotSupported, and so on. This change improves the accuracy of error reporting for various SMTP authentication mechanisms.
Enhanced the documentation by adding detailed comments for each SMTP authentication type, specifying their references to RFC documents. Corrected comments for error variables to match the corresponding authentication schemas.
Introduce `TestClient_AuthSCRAMSHAX` to verify SCRAM-SHA-1 and SCRAM-SHA-256 authentication. These tests validate the creation, connection, and closing of clients with the respective authentication methods using environment-configured credentials.
Updated `TestClient_AuthSCRAMSHA1PLUS_tlsexporter` and `TestClient_AuthSCRAMSHA1PLUS_tlsunique` to test both SCRAM-SHA-1-PLUS and SCRAM-SHA-256-PLUS authentication types. Implemented table-driven tests to improve readability and maintainability.
Enhanced code readability and maintainability by adding comprehensive documentation comments to all methods and struct definitions in the `smtp/auth_scram.go` file. This improves clarity on the functionality and usage of the SCRAM (Salted Challenge Response Authentication Mechanism) methods and structures.
Revise the sponsors section in README.md to convey gratitude more concisely. Removed redundant phrasing and made the message more direct while ensuring the intent remains clear.
Updated the Authors/Contributors section to include a graphical representation of contributors and added special thanks to Maria Letta for the logo design. Introduced a new Sponsors section to acknowledge the support from sponsors.
Refined the wording in the README.md to enhance readability and clarity. Changed some sentences to past perfect tense and added backticks around `smtp` for consistency with code references.
Revised the README to provide clearer explanations of the library's origins, dependencies, and features. Added details on the small dependency footprint and enhanced SMTP Auth methods, and emphasized the concurrency-safe reuse of SMTP connections.
Introduced two new unit tests for SCRAM-SHA1-PLUS authentication with TLS exporter and TLS unique options. These tests ensure proper client creation, connection, and disconnection processes are functioning as expected in online environments.
Replaced direct TLSConnectionState call with error handling for TLS state retrieval. Introduced SCRAM-SHA-256 support in the SMTP authentication process.
Updated method names to more accurately reflect their authentication mechanisms (SCRAM-SHA-1, SCRAM-SHA-1-PLUS, SCRAM-SHA-256, SCRAM-SHA-256-PLUS). Revised corresponding comments to improve clarity and maintain consistency.
Introduce a go.sum.license file to explicitly state the licensing terms for the go.sum file. This ensures proper attribution and compliance with open-source licensing requirements.
Introduce a method to retrieve the TLS connection state of the client's current connection. This method checks if the connection uses TLS and is established, returning appropriate errors otherwise.
Added `golang.org/x/crypto v0.27.0` and `golang.org/x/text v0.18.0` to go.mod. Updated go.sum to reflect these changes for proper dependency management.
Extended SMTP authentication to include SCRAM-SHA-1, SCRAM-SHA-1-PLUS, SCRAM-SHA-256, and SCRAM-SHA-256-PLUS methods. This enhancement provides more secure and flexible authentication options for SMTP clients.
Updated the client creation check to skip test cases if the client cannot be created, instead of marking them as errors. This ensures tests dependent on a successful client creation do not fail unnecessarily but are instead skipped.
Loop iterations in `client_test.go` were reduced from 50 to 20 for efficiency. Added new tests to verify XOAUTH2 authentication support and error handling by simulating SMTP server responses.
Correct the sequence of mutex unlocking in TLSConnectionState to ensure the mutex is always released properly. This prevents potential deadlocks and ensures the function behaves as expected in a concurrent context.
Introduced TestClient_DialSendConcurrent_online and TestClient_DialSendConcurrent_local to validate concurrent sending of messages. These tests ensure that the Client's send functionality works correctly under concurrent conditions, both in an online environment and using a local test server.
Mutex locking was relocated from the Send method in client_120.go and client_119.go to sendSingleMsg in client.go. This ensures thread-safety specifically during the message transmission process.
This commit revises locking mechanism usage around connection operations to avoid potential deadlocks and improve code clarity. Specifically, defer statements were removed and explicit unlocks were added to ensure that mutexes are properly released after critical sections. This change affects several methods, including `Close`, `cmd`, `TLSConnectionState`, `UpdateDeadline`, and newly introduced locking for concurrent data writes and reads in `dataCloser`.
This change ensures that the SetTLSConfig method is thread-safe by adding a mutex lock. The lock is acquired before any changes to the TLS configuration and released afterward to prevent concurrent access issues.
This commit removes the 'connection' field from the 'Client' struct and updates the related test logic accordingly. By using 'smtpClient.HasConnection()' to check for connections, code readability and maintainability are improved. All necessary test cases have been adjusted to reflect this change.
This commit introduces a RWMutex to the Client struct in the smtp package to ensure thread-safe access to shared resources. Critical sections in methods like Close, StartTLS, and cmd are now protected with appropriate locking mechanisms. This change helps prevent potential race conditions, ensuring consistent and reliable behavior in concurrent environments.
Modified the build tags to exclude Go 1.20 and above instead of targeting only Go 1.19. This change ensures the code is compatible with future versions of Go by not restricting it to a specific minor version.
Rearranged and grouped struct fields more logically within Client. Introduced the dialContextFunc and fallbackPort fields to enhance connection flexibility. Minor code style adjustments were also made for better readability.
Added mutex locking in the `Send` method for both `client_120.go` and `client_119.go`. This ensures thread-safe access to the connection checks and prevents potential race conditions.
Reordered and grouped fields in the Client struct for clarity. The reorganization separates logical groups of fields, making it easier to understand and maintain the code. This includes proper grouping of TLS parameters, DSN options, and debug settings.
Add mutex locking for client connections to ensure thread safety. Introduce `HasConnection` method to check active connections and `UpdateDeadline` method to handle timeout updates. Refactor connection handling in `checkConn` and `tls` methods accordingly.
Remove `connpool.go` and `connpool_test.go`. This eliminates the connection pool feature from the codebase, including associated functionality and tests. The connection pool feature is much to complex and doesn't provide the benefits expected by the concurrency feature
Updated the test name from `TestConnPool_GetContextTimeout` to `TestConnPool_GetContextCancel` to better reflect its functionality. This change improves test readability and maintains consistency with the context usage in the test.
