Database schema

Database schema

Databases

Database Name	Description
HOME	Home database for sensor nodes
_META	Metadata for nodes (including parameters)
_EXTERN	Database for temporary external data
_FIRMWARE	Versioned firmware file content
_TEST	Test database

Users

User Type	Username	Permissions	Description
Human	admin	[ALL:ALL]	Do not use unless needed
	test	[_TEST:ALL]	For testing read/writes
	generic-reader	[HOME:R]	Generic read-only permissions
Nodes	test-node	[_TEST:RW]	User for secured test node
	generic-node	[ALL:RW]	User for secured generic node
Daemons	grafana	[HOME:R]	Forwards data into secured db
	meta-reader	[_META:R, _FIRMWARE:R]	Used for identity updater, bootloader, etc.

Naming conventions

General considerations

• variables/tags: lowercase ascii letters and digits with underscores
• users: lowercase ascii letters and digits with hyphen
• databases: uppercase ascii letters and digits with underscores

Variables

Sensor variables

These variables are associated with each sensor.

Variable	Source	Slug	Units	Description
Battery voltage	Board	v_bat	V	Battery voltage in volts
Ultrasonic depth	Maxbotix Depth Sensor	maxbotix_depth	mm	Depth in millimeters
Optical rain depth	Hydreon Optical Rain Sensor	hydreon_prcp	in_10	Rain accumulation in tenths of an inch
Soil conductivity	Decagon Soil Moisture Sensor	decagon_soil_conduct	dS_m	Soil conductivity in deciSiemens/meter
Soil dielectric constant	Decagon Soil Moisture Sensor	decagon_soil_dielec		Soil dielectric constant
Soil temperature	Decagon Soil Moisture Sensor	decagon_soil_temp	C	Soil temperature in Celsius
Soil error	Decagon Soil Moisture Sensor	decagon_soil_error	N/A	Soil moisture sensor error code
Valve position	Valve	valve_trigger		Valve state and/or position

Meta variables

These variables are associated with each node.

Purpose	Variable	Slug	Type	Description
Identification	Node ID	node_id	str	Unique node ID assigned to each node
	Cellular MEID	meid	str	MEID of cellular module
Location	Site Name	site_name	str	Site name indicating location of node
	Latitude	lat	float	Latitude of node location
	Longitude	lon	float	Longitude of node location
	Elevation	elev	float	Elevation of node in meters
Firmware	App Name	app_name	str	(Human-readable) name of app
	Custom App ID	custom_app_id	hex	Built-in ID number of bootloadable file
	App Version	app_version	hex	Built-in version of bootloadable file
Parameter	Sleep timer	sleeptimer	uint	Number of wakeups before routine (sampling frequency)
	Write endpoint	node_endpoint	str	Endpoint to write data to
	Write port	node_port	uint	Port to write data to
	Write database	node_db	str	Database to write data to
	Write user	node_user	str	Username for node’s home database
	Write password	node_pass	str	Password for node’s home database
	Battery flag	vbat_flag	bool	1 to enable v_bat reading, 0 to disable
	Ultrasonic flag	ultrasonic_flag	bool	1 to enable ultrasonic sensor, 0 to disable
	Optical rain flag	optical_rain_flag	bool	1 to enable optical rain sensor, 0 to disable
	Decagon flag	decagon_flag	bool	1 to enable decagon sensor, 0 to disable
	Ultrasonic mode	ultrasonic_mode	bool	1 to take average of readings, 0 for first valid reading
	Decagon mode	decagon_mode	bool	1 to take average of readings, 0 for first valid reading

Notes

• For debugging, include user as a tag whenever performing write operation.
• When writing web apps, always sanitize query inputs to prevent SQL injection.
• We recommend using a service to change node passwords regularly.