* Storage takes care of the saving of setting when a new replica is added
* Restore replicas at startup
* Modify interactive_mg_runner + memgraph to support that data-directory can be configured in CONTEXT
* Extend e2e test
* Correct typo
* Add flag to config to specify when replication should be stored (true by default when starting Memgraph)
* Remove un-necessary "--" in yaml file
* Make sure Memgraph stops if a replica can't be restored.
* Add UT covering the parsing of ReplicaStatus to/from json
* Add assert in e2e script to check that a port is free before using it
* Add test covering crash on Jepsen
* Make sure applciaiton crashes if it starts on corrupted replications' info
Starting with a non-reponsive replica is allowed.
* Add temporary startup flag: this is needed so jepsen do not automatically restore replica on startup of main. This will be removed in T0835
* Add config for replication client/server
* Add SSL to replication
* Add semi-sync replication
* Expose necessary information about replication
* Thread pool fix
* Set BasicResult value type to void
* Add basic communication process using commit timestamp
* Add file number to req
* Add proper recovery handling
* Allow loading of WALs with same seq num
* Allow always desired commit timestamp
* Set replica timestamp for operation
* Mark non-transactional timestamp as finished
* Add file transfer over RPC
* Snapshot transfer implementation
* Allow snapshot creation only for MAIN instances
* Replica and main can have replication clients
* Use only snapshots and WALs that are from the Main storage
* Add flush lock and expose buffer
* Add fstat for file size and TryFlushing method
* Use lseek for size
Co-authored-by: Antonio Andelic <antonio.andelic@memgraph.io>
* Add tests for multiple clients
* Use variant for RPC server and clients
* Using synchronized list for replication clients, extracted variant access to a function
* Set MAIN as default, add unregister function, add a name for replication clients
* Use the regular list for clients
* Use test fixture so storage directory is cleaned
* Use seq_cst for replication_state
Co-authored-by: Antonio Andelic <antonio.andelic@memgraph.io>
This implements the initial version of synchronous replication.
Currently, only one replica is supported and that isn't configurable.
To run the main instance use the following command:
```
./memgraph \
--main \
--data-directory main-data \
--storage-properties-on-edges \
--storage-wal-enabled \
--storage-snapshot-interval-sec 300
```
To run the replica instance use the following command:
```
./memgraph \
--replica \
--data-directory replica-data \
--storage-properties-on-edges \
--bolt-port 7688
```
You can then write/read data to Bolt port 7687 (the main instance) and also you
can read the data from the replica instance using Bolt port 7688.
NOTE: The main instance *must* be started without any data and the replica
*must* be started before any data is added to the main instance.
* Add basic synchronous replication test
* Using RWLock for replication stuff
Co-authored-by: Matej Ferencevic <matej.ferencevic@memgraph.io>
Co-authored-by: Antonio Andelic <antonio.andelic@memgraph.io>
