* Allow for locks to be taken more than once in the same process without error.
* Lock directories can be created when more than one directory level is required.
* Clean up optionValid()/optionTest() logic in Lock.pm.
* Allow logging to be suppressed via logDisable() and logEnable().
* Added more flexibility in initializing and cleaning up after modules and tests.
* testResult() suppresses logging and reports exceptions.
* testException() allows messages to be matched with regular expressions.
* Refactor name/locations of common modules that setup test environments.
IMPORTANT NOTE: In prior releases it was possible to specify options on the command-line that were invalid for the current command without getting an error. An error will now be generated for invalid options so it is important to carefully check command-line options in your environment to prevent disruption.
Bug Fixes:
* Fixed an issue where options that were invalid for the specified command could be provided on the command-line without generating an error. The options were ignored and did not cause any change in behavior, but it did lead to some confusion. Invalid options will now generate an error. (Reported by Nikhilchandra Kulkarni.)
* Fixed an issue where internal symlinks were not being created for tablespaces in the repository. This issue was only apparent when trying to bring up clusters in-place manually using filesystem snapshots and did not affect normal backup and restore.
* Fixed an issue that prevented errors from being output to the console before the logging system was initialized, i.e. while parsing options. Error codes were still being returned accurately so this would not have made a process look like it succeeded when it did not. (Reported by Adrian Vondendriesch.)
* Fixed an issue where the db-port option specified on the backup server would not be properly passed to the remote unless it was from the first configured database. (Reported by Michael Vitale.)
Features:
* Added the --checksum-page option to allow pgBackRest to validate page checksums in data files when checksums are enabled on PostgreSQL >= 9.3. Note that this functionality requires a C library which may not initially be available in OS packages. The option will automatically be enabled when the library is present and checksums are enabled on the cluster. (Suggested by Stephen Frost.)
* Added the --repo-link option to allow internal symlinks to be suppressed when the repository is located on a filesystem that does not support symlinks. This does not affect any pgBackRest functionality, but the convenience link latest will not be created and neither will internal tablespace symlinks, which will affect the ability to bring up clusters in-place manually using filesystem snapshots.
* Added the --repo-sync option to allow directory syncs in the repository to be disabled for file systems that do not support them, e.g. NTFS.
* Added a predictable log entry to signal that a command has completed successfully. For example a backup ends successfully with: INFO: backup command end: completed successfully. (Suggested by Jens Wilke.)
Refactoring:
* Abstracted code to determine which database cluster is the master and which are standbys. (Contributed by Cynthia Shang.)
* Improved consistency and flexibility of the protocol layer by using JSON for all messages.
* File copy protocol now accepts a function that can do additional processing on the copy buffers and return a result to the calling process.
* Improved IO->bufferRead to always return requested number of bytes until EOF.
* For simplicity, the pg_control file is now copied with the rest of the files instead of by itself of at the end of the process. The backup command does not require this behavior and the restore copies to a temporary file which is renamed at the end of the restore.
* Simplified the result hash of File->manifest(), Db->tablespaceMapGet(), and Db->databaseMapGet().
* Improved errors returned from child processes by removing redundant error level and code.
* Code cleanup in preparation for improved stanza-create command. (Contributed by Cynthia Shang.)
* Improved parameter/result logging in debug/trace functions.
This option allows pgBackRest to validate page checksums in data files when checksums are enabled on PostgreSQL >= 9.3. Note that this functionality requires a C library which may not initially be available in OS packages. The option will automatically be enabled when the library is present and checksums are enabled on the cluster.
* The options were ignored and did not cause any change in behavior, but it did lead to some confusion. Invalid options will now generate an error.
* Removed erroneous --no-config option in help test module.
* Changed the --no-fork test option to --fork with negation to match all other boolean parameters.
