sapling/eden/mononoke/tests
Mark Thomas 640f272598 migrate from sql_ext::SqlConstructors to sql_construct
Summary:
Migrate the configuration of sql data managers from the old configuration using `sql_ext::SqlConstructors` to the new configuration using `sql_construct::SqlConstruct`.

In the old configuration, sharded filenodes were included in the configuration of remote databases, even when that made no sense:
```
[storage.db.remote]
db_address = "main_database"
sharded_filenodes = { shard_map = "sharded_database", shard_num = 100 }

[storage.blobstore.multiplexed]
queue_db = { remote = {
    db_address = "queue_database",
    sharded_filenodes = { shard_map = "valid_config_but_meaningless", shard_num = 100 }
}
```

This change separates out:
* **DatabaseConfig**, which describes a single local or remote connection to a database, used in configuration like the queue database.
* **MetadataDatabaseConfig**, which describes the multiple databases used for repo metadata.

**MetadataDatabaseConfig** is either:
* **Local**, which is a local sqlite database, the same as for **DatabaseConfig**; or
* **Remote**, which contains:
    * `primary`, the database used for main metadata.
    * `filenodes`, the database used for filenodes, which may be sharded or unsharded.

More fields can be added to **RemoteMetadataDatabaseConfig** when we want to add new databases.

New configuration looks like:
```
[storage.metadata.remote]
primary = { db_address = "main_database" }
filenodes = { sharded = { shard_map = "sharded_database", shard_num = 100 } }

[storage.blobstore.multiplexed]
queue_db = { remote = { db_address = "queue_database" } }
```

The `sql_construct` crate facilitates this by providing the following traits:

* **SqlConstruct** defines the basic rules for construction, and allows construction based on a local sqlite database.
* **SqlShardedConstruct** defines the basic rules for construction based on sharded databases.
* **FbSqlConstruct** and **FbShardedSqlConstruct** allow construction based on unsharded and sharded remote databases on Facebook infra.
* **SqlConstructFromDatabaseConfig** allows construction based on the database defined in **DatabaseConfig**.
* **SqlConstructFromMetadataDatabaseConfig** allows construction based on the appropriate database defined in **MetadataDatabaseConfig**.
* **SqlShardableConstructFromMetadataDatabaseConfig** allows construction based on the appropriate shardable databases defined in **MetadataDatabaseConfig**.

Sql database managers should implement:

* **SqlConstruct** in order to define how to construct an unsharded instance from a single set of `SqlConnections`.
* **SqlShardedConstruct**, if they are shardable, in order to define how to construct a sharded instance.
* If the database is part of the repository metadata database config, either of:
    * **SqlConstructFromMetadataDatabaseConfig** if they are not shardable.  By default they will use the primary metadata database, but this can be overridden by implementing `remote_database_config`.
    * **SqlShardableConstructFromMetadataDatabaseConfig** if they are shardable.  They must implement `remote_database_config` to specify where to get the sharded or unsharded configuration from.

Reviewed By: StanislavGlebik

Differential Revision: D20734883

fbshipit-source-id: bb2f4cb3806edad2bbd54a47558a164e3190c5d1
2020-04-02 05:27:16 -07:00
..
fixtures mononoke: make blobrepo and its dependencies OSS buildable 2020-03-31 04:02:45 -07:00
integration migrate from sql_ext::SqlConstructors to sql_construct 2020-04-02 05:27:16 -07:00
utils mononoke: make blobrepo and its dependencies OSS buildable 2020-03-31 04:02:45 -07:00
write_stub_log_entry/src Manual synchronization of fbcode/eden and facebookexperimental/eden 2020-02-11 11:42:43 +01:00