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message contract

The written agreement about what a message contains, so sender and receiver agree without reading each other's code.

A message contract specifies a message's topic or endpoint, fields, types, units, optionality and version, and the rules for changing it compatibly.

Examples

  • The greenhouse contract for gh1/gh-a1/telemetry/climate lists each field, its type, unit and whether it is required: v an integer, temp_c a number in degrees Celsius, rh_pct a percentage.

See also

schema version JSON topic tree
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