Register for an account

To be able to explore and use the the Companies House streaming API, you need to register a user account with Companies House.

Register your application and receive an API key

Visit the Your Applications page of the Companies House Developer Hub. This will show you the REST API and streaming API applications you have already registered, and allow you to register further applications.

Applications that are to use the streaming API must be registered as such, the REST API and streaming API keys are not interchangable.

Register a new application

To register a new application, click the Register an application button.

You will now be asked which type of application you are registering, choose Streaming API.

Fill in your Application name, giving it a meaninful description and, if appropriate, a list of Restricted IPs and when you're done, click Register.

The hub will register your application, and provide you with a unique streaming API key that you will use to authenticate your application every time you connect to a streaming API.

Using Basic authentication

When connecting to the streaming API, you authenticate using Basic authentication, which is wildly supported by HTTP client libraries and command line tools.

To authorise using Basic authentication, the client sends the server an Authorization HTTP header specifying a scheme type of Basic and a value that is constructed as follows:

  1. An ASCII colon ':' is appended to the end of the streaming API key
  2. Basic-credentials are created by encoding this concatenated sequence by using Base64 RFC4648 into a sequence of US-ASCII characters RFC4648.

Given an example streaming API key of a-streaming-api-key, the complete HTTP authorization header would be:

Authorization: Basic YS1zdHJlYW1pbmctYXBpLWtleTo==

Note that you will get a different and invalid base64 encoded value if you ommit the colon ':' from the end of the API key before encoding.

The following curl request authenticates with Basic authentication:

curl -v -u a-streaming-api-key: ""