PostHog Schema Enforcer Plugin (WIP)

Objective

This plugin allows users to specify schemas for events ingested so that they can prevent the ingestion of events that don't match a specified schema.

What it currently does

Prevents ingestion if the event:

• Is missing a required property
• Has a property with the wrong type
• Is not included in the file and onlyIngestEventsFromFile is true

It also:

• Removes all other properties from an event except selected ones if acceptOnlySchemaProps is true

Configuration is done via a JSON file uploaded as a plugin attachment

Example config file

{
    "onlyIngestEventsFromFile": true,
    "eventSchemas": {
        "testEvent": {
            "acceptOnlySchemaProps": true,
            "schema": {
                "foo": {
                    "type": "string",
                    "required": false
                },
                "bar": {
                    "type": "number",
                    "required": true
                },
                "baz": {
                    "type": "boolean",
                    "required": false
                }
            } 
        }
    }
}

To Do

Short Term

• Create an interface to generate the config file (In Progress)
• Friendlier config (e.g. accept 1, 'true', and true for toggles)
• More config options, such as:
  • List of events to ingest
  • Thresholds (e.g. 'greater than' for number type)
  • Default values
  • ...
• Tests

Future

• Accept YAML
• Powerful threshold and filtering
• More options for what to do with "bad events" beyond not ingesting them

Questions?

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