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Hubble serves a gRPC API on port 2283 by default.

Using the API

We recommend using a library like hub-nodejs to interact with Hubble's gRPC APIs. Please refer to its documentation for how to use it.

Other languages

The protobufs for the gRPC API are available within the hub-monorepo. They can be used to generate bindings for other clients built using other languages. Note that by default, hubs rely on the javascript ts-proto library's serialization byte order to verify messages hashes. If you are using a different client, you may need to use the data_bytes field with the raw serialized bytes when calling SubmitMessage in order for the message to be considered valid. Refer to the SubmitMessage HTTP API docs for more details.