/blueredis

Blueprints-enabled graph over Redis

Primary LanguageJava

This is a straightforward and rather naïve implementation of a Blueprints-enabled graph over Redis.

Blueprints is a database-agnostic library for handling graphs. Blueredis allows you to run Blueprints on top of redis. Also see Pipes and Gremlin to see what this integration will also allow you to do.

Running

Requires Redis 2.x compatible version of JRedis (git clone this repo, and you'll get a jar)

Graph db = new RedisGraph();

String password = "pass";
Graph db1 = new RedisGraph(password);

String host = "127.0.0.1";
int port = 6379;
Graph db2 = new RedisGraph(host, port);

int database = 10;
Graph db3 = new RedisGraph(host, port, pass, database);

After this you work with the database as with any Blueprints-enabled graph.

Peculiarities

ID creation

RedisGraph handles id creation for you. Any id parameter passed to addVertex/addEdge will be ignored. All ids are of type long

Serializing properties (off by default)

By default all properties are saved and retrieved as strings, regardless of the type of object you pass to addVertex. If you want to save actual objects/values, call graph.serializeProperties(true). Note though, that it uses Base64 encoding on top of Java serialization so it may take up a lot of space.

Transactions

Currently transactions are not supported

Indexing (off by default)

WARNING! Indexing support that's bundled with Blueredis is rather resource intensive, manipulates quite a few key-value pair in redis and negatively affects performance. If speed is your primary concern, don't use the default indexing implementation

Blueredis implements an index for both vertex and edge properties. This implementation is based on A fast, fuzzy, full-text index using Redis.

Turning indexing on

By default indexing is off. To turn it on, call graph.setIndexing(true). To turn it back on, call graph.setIndexing(false).

Implementing your own

You may wish to implement your own indexing service. To do this:

  • implement Blueprints' Index and AutomaticIndex interfaces
  • override Blueredis' RedisIndexManager class
  • call graph.setIndexing(true, yourManagerInstance) and pass an instance of your indexManager to it

Implementation

Vertices

Each vertex is represented by the following keys:

  • vertex:ID, vertex id. This one is used to test if a vertex exists
  • vertex:ID:properties, a hash of all vertex properties
  • vertex:ID:edges:in, a set of all incoming edges
  • vertex:ID:edges:out, a set of all outgoing edges

Edges

Each edge is represented by the following keys:

  • edge:ID, edge id. This one is used to test if an edge exists
  • edge:ID:label, a string containing the edge's label
  • edge:ID:in, index of "in" vertex
  • edge:ID:out, index of "out" vertex
  • edge:ID:properties, a hash of all edge properties

Globals

This are just some keys that hold values necessary for Blueredis to work:

  • globals:next_vertex_id, a counter that's incremented each time a new vertex is added
  • globals:next_edge_id, a counter that's incremented each time a new edge is added
  • globals:vertices, a sorted list of all vertex ids
  • globals:edges, a sorted list of all edge ids

Indices

This section describes default indexing support that's bundled with Blueredis. You're free to implement your own.

Indices are stored in keys that all start with an index:...

  • index:auto - prefix for all automatic indices
  • index:manual - prefix for all manual indices For all of the above:
    • index:type:index_name, where index_name is a user-supplied index name - prefix for index data for index_name
    • index:type:index_name:key_name, where key_name is a user-supplied key name - prefix for index data for key_name key
    • index:type:index_name:key_name:metaphone, where metaphone is a calculated metaphone for a value - contains a list of vertex ids that have a key key_name with a value whose metaphone matches metaphone
  • index:meta:indices:auto - a list of automatic indices
  • index:meta:indices:manual - a list of manual indices
  • index:meta:auto - prefix for all meta information on automatic indices
  • index:meta:manual - prefix for all meta information on manual indices For index:meta:(auto|manual) above:
    • index:meta:type:index_name:class, where index_name is a user-supplied index name - contains what class the index works on: vertex, edge, etc.
    • index:meta:type:index_name:keys, where index_name is a user-supplied index name - contains a list of keys for this index

Tests

RedisGraph now passes tinkerpop's tests.

Benchmarks

An old benchmark can be found here: benchmarks page in wiki. Note that reeds seems to perform better under load than during singular requests. A newer benchmark will be published as soon as there's one :)