Client Libraries

Dgraph client libraries allow you to run DQL transactions, queries and mutations in various programming languages.

If you are interested in clients for GraphQL endpoint, please refer to GraphQL clients section.

Go, python, Java, C# and JavaScript clients are using gRPC: protocol and Protocol Buffers (the proto file used by Dgraph is located at api.proto).

A JavaScript client using HTTP: is also available.

It’s possible to interface with Dgraph directly via gRPC or HTTP. However, if a client library exists for your language, that will be an easier option.

Transactions

Dgraph clients perform mutations and queries using transactions. A transaction bounds a sequence of queries and mutations that are committed by Dgraph as a single unit: that is, on commit, either all the changes are accepted by Dgraph or none are.

A transaction always sees the database state at the moment it began, plus any changes it makes — changes from concurrent transactions aren’t visible.

On commit, Dgraph will abort a transaction, rather than committing changes, when a conflicting, concurrently running transaction has already been committed. Two transactions conflict when both transactions:

• write values to the same scalar predicate of the same node (e.g both attempting to set a particular node’s address predicate); or
• write to a singular uid predicate of the same node (changes to [uid] predicates can be concurrently written); or
• write a value that conflicts on an index for a predicate with @upsert set in the schema (see upserts).

When a transaction is aborted, all its changes are discarded. Transactions can be manually aborted.

In this section

• Go
• Python
• JavaScript
• C#
• Java
• Raw HTTP
• Unofficial Dgraph Clients