Database

Parameter database and ring buffers.

Both classes below are verbatim from the device firmware (firmware_core.py of Logger Pro and the findyIoT module). The parameter registry itself (databaseParams, aka db.params) lives in the user-editable last.py and is passed into the database constructor - see System IDs for the entry format and the full ID table.

Note

Methods reference the firmware module globals (modem, db, device, setError…) exactly as on the device.

class findylab.database.database(params)

Persistent key/value storage on top of btree (the “mydb” file).

Verbatim class from firmware_core.py. Keys are HiGPS parameter IDs registered in the dict passed to the constructor - on a device that dict is databaseParams from the user-editable last.py:

db = database(databaseParams)

Values are stored as bytes; read() also returns the encoded default for a registered-but-missing key.

__init__(params)

Loads the existing “mydb” btree file into RAM.

Parameters:

params (dict) – The parameter registry (databaseParams from last.py); stored as the class-level database.params.

getParameterData(uri)

Returns the registry row for a parameter ID.

Parameters:

uri (str) – Parameter ID, e.g. '421'.

Returns:

The registry entry, or False for unknown IDs.

Return type:

list

getParameterByHiGPS(higpsId)

Returns the registry row for a HiGPS parameter ID.

Parameters:

higpsId (str) – Parameter ID.

Returns:

The registry entry, or False for unknown IDs.

Return type:

list

initDefaults()

Factory-initializes the database.

Deletes an existing “mydb” (and resets so the next boot starts clean), reads the IMEI from the modem, then writes every storage-type-0 parameter’s default value.

read(property, echo=True)

Reads a parameter value.

Parameters:

• property (str or bytes) – Parameter ID.

• echo (bool) – Print the value while reading (debug aid).

Returns:

The stored value; the encoded default when the key is missing but registered; False for unknown IDs.

Return type:

bytes

write(property, value)

Writes a parameter value into RAM.

int/str values are converted to bytes. Call store() to persist to flash.

Parameters:

• property (str or bytes) – Parameter ID.

• value (int or str or bytes) – New value.

Returns:

True on success.

Return type:

bool

store()

Persists the RAM changes to the “mydb” btree file.

No-op when nothing was written since the last store. Buffer-type parameters (type 3) also store their child slots (key0..``key99``).

Returns:

True.

Return type:

bool

class findylab.database.buffer

Ring buffers over database (slots "540"+n).

Verbatim class from firmware_core.py. Never instantiated - the methods take no self and are called directly:

buffer.create('540')

Used to keep pulse-count series between successful reports; the current slot index lives in parameters 538/539.

create()

Opens a fresh buffer slot.

Finds a free slot (0..99), writes the header (log period + timestamp + base counter value) and records the slot index in parameter 538/539.

Parameters:

bufferName (str) – '540' or '541'.

Returns:

The slot index used.

Return type:

int

get()

Returns the first full buffer slot.

Parameters:

bufferName (str) – '540' or '541'.

Returns:

(period, timestamp, base_value, data) or False when no slot holds data.

Return type:

tuple

put(data)

Appends bytes to the current buffer slot.

Parameters:

• bufferName (str) – '540' or '541'.

• data (bytes) – Payload to append (e.g. a 2-byte pulse delta).

remove()

Clears the first full buffer slot.

Parameters:

bufferName (str) – '540' or '541'.

Returns:

True when a slot was cleared.

Return type:

bool