MDS milliseconds timestamp constraints

[tonial]

Is your feature request related to a problem? Please describe.

As an agency, we often see second timestamps instead of millisecond timestamp when a provider uses MDS for the first time and tries to send us data.

Describe the solution you'd like

In order to speed up bug detection on our side, we added a constraint that specifies that a timestamp should have 13 digits which allows dates between 2001-9-9 and 2286-11-20 (which is big enough).
Adding this into the Timestamp description and json schema could help to prevent this mistake.

Is this a breaking change

• No, not breaking

Impacted Spec

All timestamps in all APIs

Describe alternatives you've considered

Additional context

[schnuerle]

Thank you @tonial. A reasonable request that could be updated in the next release. As the schema expert, what do you think @thekaveman ?

[thekaveman]

Yes, very reasonable request and should be as easy as modifying the common timestamp definition.

Right now, we have:

"timestamp": {
  "$id": "#/definitions/timestamp",
  "type": "number",
  "description": "Integer milliseconds since Unix epoch",
  "multipleOf": 1.0,
  "minimum": 0
},

Because this is a number type, we can't do a (string) length check. But an easy modification would be to change the minimum to correspond to @tonial's 13-digit starting point of 1000000000000.

Alternatively, a more realistic minimum could correspond to (for example) Jan 1, 2018 (the year MDS was first released), in UTC 1514764800000.

[schnuerle]

Approved via PR #648. Thank you!