gremcos

Gremcos is a fork of schwartzmx/gremtune with alterations to make it compatible with Gremlin API of Azure Cosmos DB which is a Graph Database (Gremlin API) for Azure.

Gremcos is a fast, efficient, and easy-to-use client for the TinkerPop graph database stack. It is a gremlin language driver which uses WebSockets to interface with gremlin server and has a strong emphasis on concurrency and scalability. Please keep in mind that gremcos is still under heavy development and although effort is being made to fully cover gremcos with reliable tests, bugs may be present in several areas.

Installation

go get github.com/supplyon/gremcos

Examples

• See: examples/README.md

Hints

Response Format

This implementation supports Graphson 2.0 (not 3) in order to be compatible to CosmosDB. This means all the responses from the CosmosDB server as well as the responses from the local gremlin-server have to comply with the 2.0 format.

Azure Cosmos Gremlin Implementation Differences

Modifications where made to gremtune in order to be compliant to Azure Cosmos DB. Differences in gremlin support can be found at: Azure Cosmos DB Gremlin compatibility

This implementation is only working/ compatible with TinkerPop 3.4.0.

Cosmos DB specific error handling is done and described at ErrorHandling.md. For example error responses returned by Cosmos due to a usage rate limit violation are handled accordingly.

Local Development

For being able to develop locally against a local graph data base one can start a local gremlin-server via make infra.up. In order to be able to use all features the query language has to be switched to QueryLanguageTinkerpopGremlin.

Switch the Query Language

Since the query language of the Cosmos DB and the tinkerpop gremlin implementation are not 100% compatible it is possible to set the language based on the use-case. The following piece of code depicts how to set the query language.

    // If you want to run your queries against a apache tinkerpop gremlin server it is recommended
    // to switch the used query language to QueryLanguageTinkerpopGremlin.
    // Per default the CosmosDB compatible query language will be used.
    api.SetQueryLanguageTo(api.QueryLanguageTinkerpopGremlin)

License

See LICENSE

3rd Party Licenses

• difflib license