Medium One accepts data as events in JSON format. Each event has an “observed_at” time and “event_data”. The “observed_at” is the timestamp in ISO format at which the event occurred. It is an optional field -- if not specified, then the current timestamp will be used. The “event_data” consists of “tags” (also known as “keys”) and their corresponding “values”. When these events are sent in, they are sorted in different data streams. In addition to data streams, each tag is also categorized by data type.
Medium One also has a Store which maintains persistent, but not durable, string variables.