Hydra

Project	Package
Surveily.Hydra.Core
Surveily.Hydra.Events
Surveily.Hydra.Tools

A set of components to take the most advantage of performance and capacity of Azure Storage.

Hydra is Azure Subscription agnostic, which means it is possible to use Storage Accounts from different Azure Subscriptions. This functionality gives the developer configurable IOPS and Disk Space with no upper limits.

Overview

Hydra.Core

class Hydra : IHydra

A central component for scaling across multiple Storage Accounts. It is using an ISharding strategy to compute consistent hashes that pick a right Storage Account by key provided.

class JumpSharding : ISharding

Default implementation of ISharding provided is JumpSharding that implement's Jump Consistent Hash.

Disclaimer

Hydra.Core doesn't manage shard migration, which means you are constrained the amount of Storage Accounts you start of with. The more the better.

Advanced usage

It is possible to have multiple instances of Hydra, configured to point at different and/or the same Storage Accounts, with different and/or the same ISharding implementations. That feature gives the developer maximum flexibility for making sure the right data is distributed in the right way.

Example

Example usage can be found in the Hydra.Tests.Integration namespace.

Hydra.Events

class StreamContainer : IStreamContainer

A central component for managing Stream's underlying storage. It requires an IHydra component to gain access to the storage.

class Stream : IStream

This component is in charge of writing and reading events to a stream in storage.

Disclaimer

Hydra.Events has a limitation dictated by Azure Storage. Currently one stream can consist of up to 50,000 events and 195GB of space.

Example

Example usage can be found in the Hydra.Tests.Integration namespace.

Hydra.Tools

Tools package is a set of utilities to help developers manage re-sharding via data copy and data deletion.

Commands

$ hydra --help
Surveily.Hydra.Tools 1.0.0
Copyright © Surveily sp. z o.o.

  cp         Copies data between Azure Storage Accounts. WARNING! If you specify multiple sources or targets, you will use Hydra Jump Sharding. Very useful for re-sharding data.

  rm         Remove all objects from target storage accounts.

  help       Display more information on a specific command.

  version    Display version information.

Copy Task

Copies data between Azure Storage Accounts. WARNING! If you specify multiple sources or targets, you will use Hydra Jump Sharding. Very useful for re-sharding data.

$ hydra cp --help
Surveily.Hydra.Tools 1.0.0
Copyright © Surveily sp. z o.o.

  -s, --source             Required. Accounts to read from.

  -t, --target             Required. Accounts to write to.

  -o, --object             Scope the task to single Storage object by name (eg. Table name).

  -f, --override-fields    Select which fields to override.

  -v, --override-values    Set value for the overriden properties.

  --help                   Display this help screen.

  --version                Display version information.

Clear Task

Deletes all data from Azure Storage Accounts.

$ hydra rm --help
Surveily.Hydra.Tools 1.0.0
Copyright © Surveily sp. z o.o.

  -t, --target    Required. Accounts to write to.

  -o, --object    Scope the task to single Storage object by name (eg. Table name).

  --help          Display this help screen.

  --version       Display version information.