Bug Fixes:
* Fix zero-length reads causing problems for IO filters that did not expect them. (Reported by brunre01, jwpit, Tomasz Kontusz, guruguruguru.)
* Fix reliability of error reporting from local/remote processes.
* Fix Posix/CIFS error messages reporting the wrong filename on write/sync/close.
Refactor storage layer to allow for new repository filesystems using drivers. (Reviewed by Cynthia Shang.)
Refactor IO layer to allow for new compression formats, checksum types, and other capabilities using filters. (Reviewed by Cynthia Shang.)
* pgBackRest version number included in command start INFO log output.
* Process ID logged for local process start/stop INFO log output.
* Fixed missing expect output for help module.
* Fixed an issue where local processes were not disconnecting when complete and could later timeout. (Reported by Todd Vernick.)
* Fixed an issue where the protocol layer could timeout while waiting for WAL segments to arrive in the archive. (Reported by Todd Vernick.)
Master and standby can both be configured on the backup server and pgBackRest will automatically determine which is the master. This means no configuration changes for backup are required after failing over from a master to standby when a separate backup server is used.
This was worked out as part of the test suite refactor [c8f806a] but not committed with it because of the large number of expect logs changes involved. Keeping them separate made it easier to audit the changes in the refactor.
* Make the code more modular and object-oriented.
* Multiple Docker containers can now be created for a single test to simulate more realistic environments.
* Containers now use a squid proxy for apt/yum to speed builds.
* Obsolete containers are removed by the <br-option>--vm-force</br-option> option.
* Greatly reduced the quantity of Docker containers built by default. Containers are only built for PostgreSQL versions specified in db-minimal and those required to build documentation. Additional containers can be built with --db-version=all or by specifying a version, e.g. --db-version=9.4.
This change allows for easier testing since all files are local on the host VM and can be easily accessed without using `docker exec`. In addition, this change is required to allow multiple Docker containers per test case which is coming soon.
* All files and directories linked from PGDATA are now included in the backup. By default links will be restored directly into PGDATA as files or directories. The --link-all option can be used to restore all links to their original locations. The --link-map option can be used to remap a link to a new location.
* Removed --tablespace option and replaced with --tablespace-map-all option which should more clearly indicate its function.
* Added detail log level which will output more information than info without being as verbose as debug.
* The repo-path option now always refers to the repository where backups and archive are stored, whether local or remote, so the repo-remote-path option has been removed. The new spool-path option can be used to define a location for queueing WAL segments when archiving asynchronously. Otherwise, a local repository is no longer required.
* Implemented a new config format which should be far simpler to use. See the User Guide and Configuration Reference for details but for a simple configuration all options can now be placed in the stanza section. Options that are shared between stanzas can be placed in the [global] section. More complex configurations can still make use of command sections though this should be a rare use case.
* The default configuration filename is now pgbackrest.conf instead of pg_backrest.conf. This was done for consistency with other naming changes but also to prevent old config files from being loaded accidentally.
* The default repository name was changed from /var/lib/backup to /var/lib/pgbackrest.
* Lock files are now stored in /tmp/pgbackrest by default. These days /run/pgbackrest would be the preferred location but that would require init scripts which are not part of this release. The lock-path option can be used to configure the lock directory.
* Log files are now stored in /var/log/pgbackrest by default and no longer have the date appended so they can be managed with logrotate. The log-path option can be used to configure the lock directory.
* Executable filename changed from pg_backrest to pgbackrest.
