If you want to communicate directly with the streamd server, you can use the WebSocket API or JSON-RPC API. Both APIs use the same list of commands, with almost identical parameters in each command. Unlike the Radar-REST API, which provides a simplified interface on top of the WebSocket API for easier integration, these APIs provide full-power radar, but with slightly more complex requirements:
The WebSocket API uses the WebSocket protocol available in most browsers and JavaScript implementations to achieve persistent two-way communication. There is not a 1:1 correlation between requests and responses. Some requests push the server to return multiple asynchronous messages; other times, responses may arrive in a different order than the requests that pushed them. The streamd server can be configured to accept secure (wss://), insecure (ws://) WebSocket connections, or both.
The JSON-RPC API relies on the same request-response communication over HTTP or HTTPs. (The streamd server can be set up to accept HTTP, HTTPS, or both.) For commands that advance multiple responses, you can provide a callback URL.
The streamd program can also be used as a fast command line client to send JSON-RPC requests to a running streamd server. This is designed for administrative purposes and is not a supported API.
In general, we recommend using WebSocket because the WebSocket push paradigm has less latency and network overhead. JSON-RPC must open and close HTTP connections when processing each individual message. WebSocket is also more reliable, and you don't have to worry too much about losing information and establishing multiple connections. However, all three have valid use cases and will continue to be supported for the foreseeable future.
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