{
	"$schema": "http://iglucentral.com/schemas/com.snowplowanalytics.self-desc/schema/jsonschema/1-0-0#",
	"description": "Schema for a client-generated user session",
	"self": {
		"vendor": "com.snowplowanalytics.snowplow",
		"name": "client_session",
		"format": "jsonschema",
		"version": "1-0-1"
	},
	"type": "object",
	"properties": {
		"userId": {
			"type": "string",
			"pattern": "^[0-9a-f]{8}-([0-9a-f]{4}-){3}[0-9a-f]{12}$|^[0-9a-f]{16}$",
			"maxLength": 36,
			"description": "An identifier for the user of the session"
		},
		"sessionId": {
			"type": "string",
			"format": "uuid",
			"description": "An identifier for the session"
		},
		"sessionIndex": {
			"type": "integer",
			"minimum": 0,
			"maximum": 2147483647,
			"description": "The index of the current session for this user"
		},
		"previousSessionId": {
			"type": [
				"null",
				"string"
			],
			"format": "uuid",
			"description": "The previous session identifier for this user"
		},
		"storageMechanism": {
			"type": "string",
			"enum": [ "SQLITE", "COOKIE_1", "COOKIE_3", "LOCAL_STORAGE", "FLASH_LSO" ],
			"description": "The mechanism that the session information has been stored on the device"
		},
		"firstEventId": {
			"type": [
				"null",
				"string"
			],
			"format": "uuid",
			"description": "The optional identifier of the first event id for this session"
		}
	},
	"required": [ "userId", "sessionId", "sessionIndex", "previousSessionId", "storageMechanism" ],
	"additionalProperties": false
}