Event modeling

The first step in event modeling is to express the event in English in the following form:

Subject-verb-direct object

For this example, we are modeling the event customer consults the ETH price:

• The subject in this sentence is customer, a noun in nominative case. The subject is the entity performing the action.
• The verb in this sentence is consults; it describes the action performed by the subject.
• The direct object in this sentence is ETH price. The object is the entity in which the action is being done.

We can represent our message in several message formats (covered in other sections of this book):

• JavaScript Object Notation (JSON)
• Apache Avro
• Apache Thrift
• Protocol Buffers

JSON is easily read and written by both humans and machines. For example, we could chose binary as the representation, but it has a rigid format and it was not designed for humans to...