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bvisness/ntutil.py

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A helpful wrapper for the WPILib NetworkTables API.
Raw
ntutil.py
from typing import Any, Dict, Generic, List, Type, TypeVar
import ntcore
import wpilib
import wpiutil.log
nt = ntcore.NetworkTableInstance.getDefault()
T = TypeVar("T")
class Topic(Generic[T]):
"""
A single entry in NetworkTables that can be read from or written to.
"""
def __init__(self, topic, default: T):
"""
Do not create instances of Topic() directly. Instead, call the helper
functions like `getIntegerTopic` and `getStructTopic`.
"""
self.publisher = topic.publish()
self.subscriber = topic.subscribe(default)
def get(self, defaultValue: T | None = None) -> T:
"""
Gets the most recent value published to the topic, or `defaultValue` if
no value has been published.
"""
if defaultValue is None:
return self.subscriber.get()
else:
return self.subscriber.get(defaultValue)
def set(self, value: T) -> None:
"""
Sets the topic's value, publishing it to NetworkTables.
"""
self.publisher.set(value)
def setDefault(self, value: T) -> None:
"""
Set's the default value of the topic, to be returned if no value has
been published.
"""
self.publisher.setDefault(value)
class DummyTopic(Topic[T], Generic[T]):
"""
A phony topic that publishes and receives nothing. Useful as a default if
you want NetworkTables logging to be optional.
"""
def __init__(self, default: T | None = None):
pass
def get(self, defaultValue: T | None = None) -> T:
# Returns None if no defaultValue is provided, but you know, who cares.
# This is under-specified in the underlying library too.
return defaultValue # type: ignore
def set(self, value: T) -> None:
pass
def setDefault(self, value: T) -> None:
pass
class Folder:
"""
An object that can be used to create Topics with a specific path. Useful
when you want a group of topics for a specific object.
```
nt = ntutil.Folder("MySubsystem")
armAngleTopic = nt.getFloatTopic("ArmAngle") # Creates MySubsystem/ArmAngle
clawOpenTopic = nt.getBooleanTopic("ClawOpen") # Creates MySubsystem/ClawOpen
```
You can also create subfolders by calling `getFolder` again.
"""
def __init__(self, prefix: str):
"""
Creates a folder with a given path prefix. Do not call this directly;
instead, call `getFolder`.
"""
self.prefix = prefix
def getFolder(self, name: str):
"""
Creates a subfolder of the current folder.
"""
return Folder(self.prefix + "/" + name)
def getBooleanArrayTopic(self, name: str, defaultValue: List[bool] = []) -> Topic[List[bool]]:
return Topic(nt.getBooleanArrayTopic(self.prefix + "/" + name), defaultValue)
def getBooleanTopic(self, name: str, defaultValue: bool = False) -> Topic[bool]:
return Topic(nt.getBooleanTopic(self.prefix + "/" + name), defaultValue)
def getFloatArrayTopic(self, name: str, defaultValue: List[float] = []) -> Topic[List[float]]:
return Topic(nt.getFloatArrayTopic(self.prefix + "/" + name), defaultValue)
def getFloatTopic(self, name: str, defaultValue: float = 0) -> Topic[float]:
return Topic(nt.getFloatTopic(self.prefix + "/" + name), defaultValue)
def getIntegerArrayTopic(self, name: str, defaultValue: List[int] = []) -> Topic[List[int]]:
return Topic(nt.getIntegerArrayTopic(self.prefix + "/" + name), defaultValue)
def getIntegerTopic(self, name: str, defaultValue: int = 0) -> Topic[int]:
return Topic(nt.getIntegerTopic(self.prefix + "/" + name), defaultValue)
def getStringArrayTopic(self, name: str, defaultValue: List[str] = []) -> Topic[List[str]]:
return Topic(nt.getStringArrayTopic(self.prefix + "/" + name), defaultValue)
def getStringTopic(self, name: str, defaultValue: str = "") -> Topic[str]:
return Topic(nt.getStringTopic(self.prefix + "/" + name), defaultValue)
def getStructArrayTopic(self, name: str, type: Type[T], defaultValue: List[T] = []) -> Topic[List[T]]:
return Topic(nt.getStructArrayTopic(self.prefix + "/" + name, type), defaultValue)
def getStructTopic(self, name: str, type: Type[T], defaultValue: T | None = None) -> Topic[T]:
if defaultValue is None:
defaultValue = type()
return Topic(nt.getStructTopic(self.prefix + "/" + name, type), defaultValue)
class DummyFolder(Folder):
"""
A phony folder that creates phony topics. Useful as a default if you want
NetworkTables logging to be optional.
"""
def __init__(self, prefix: str = "DUMMY"):
self.prefix = prefix
def getFolder(self, name: str):
return DummyFolder(self.prefix + "/" + name)
def getBooleanArrayTopic(self, name: str, defaultValue: List[bool] = []) -> Topic[List[bool]]:
return DummyTopic(defaultValue)
def getBooleanTopic(self, name: str, defaultValue: bool = False) -> Topic[bool]:
return DummyTopic(defaultValue)
def getFloatArrayTopic(self, name: str, defaultValue: List[float] = []) -> Topic[List[float]]:
return DummyTopic(defaultValue)
def getFloatTopic(self, name: str, defaultValue: float = 0) -> Topic[float]:
return DummyTopic(defaultValue)
def getIntegerArrayTopic(self, name: str, defaultValue: List[int] = []) -> Topic[List[int]]:
return DummyTopic(defaultValue)
def getIntegerTopic(self, name: str, defaultValue: int = 0) -> Topic[int]:
return DummyTopic(defaultValue)
def getStringArrayTopic(self, name: str, defaultValue: List[str] = []) -> Topic[List[str]]:
return DummyTopic(defaultValue)
def getStringTopic(self, name: str, defaultValue: str = "") -> Topic[str]:
return DummyTopic(defaultValue)
def getStructArrayTopic(self, name: str, type: Type[T], defaultValue: List[T] = []) -> Topic[List[T]]:
return DummyTopic(defaultValue)
def getStructTopic(self, name: str, type: Type[T], defaultValue: T | None = None) -> Topic[T]:
if defaultValue is None:
defaultValue = type()
return DummyTopic(defaultValue)
_globalFolder = Folder("")
def getFolder(name: str) -> Folder:
return Folder("/" + name)
def getBooleanArrayTopic(name: str, defaultValue: List[bool] = []):
return _globalFolder.getBooleanArrayTopic(name, defaultValue)
def getBooleanTopic(name: str, defaultValue: bool = False) -> Topic[bool]:
return _globalFolder.getBooleanTopic(name, defaultValue)
def getFloatArrayTopic(name: str, defaultValue: List[float] = []) -> Topic[List[float]]:
return _globalFolder.getFloatArrayTopic(name, defaultValue)
def getFloatTopic(name: str, defaultValue: float = 0) -> Topic[float]:
return _globalFolder.getFloatTopic(name, defaultValue)
def getIntegerArrayTopic(name: str, defaultValue: List[int] = []) -> Topic[List[int]]:
return _globalFolder.getIntegerArrayTopic(name, defaultValue)
def getIntegerTopic(name: str, defaultValue: int = 0) -> Topic[int]:
return _globalFolder.getIntegerTopic(name, defaultValue)
def getStringArrayTopic(name: str, defaultValue: List[str] = []) -> Topic[List[str]]:
return _globalFolder.getStringArrayTopic(name, defaultValue)
def getStringTopic(name: str, defaultValue: str = "") -> Topic[str]:
return _globalFolder.getStringTopic(name, defaultValue)
def getStructArrayTopic(name: str, type: Type[T], defaultValue: List[T] = []) -> Topic[List[T]]:
return _globalFolder.getStructArrayTopic(name, type, defaultValue)
def getStructTopic(name: str, type: Type[T], defaultValue: T | None = None) -> Topic[T]:
return _globalFolder.getStructTopic(name, type, defaultValue)
# WPILib logging utilities
def log(msg: Any):
"""
Logs a message to both stdout and the /messages entry of NetworkTables
(visible when viewing log files).
"""
wpilib.DataLogManager.log(f"{msg}")
_originalAlertText: Dict[wpilib.Alert, str] = {}
def logAlert(alert: wpilib.Alert, msg: Any):
"""
Enables an Alert and also logs an additional message. Useful for indicating
a specific value that caused an error, or to provide more context. Consider
using this whenever you would instead use a simple `ntutil.log`.
To avoid spam, this method will only log when the message changes.
"""
global _originalAlertText
if alert not in _originalAlertText:
_originalAlertText[alert] = alert.getText()
fullMsg = f"{_originalAlertText[alert]}: {msg}"
if alert.getText() != fullMsg:
log(fullMsg)
alert.setText(fullMsg)
alert.set(True)
def getBooleanArrayLog(name: str):
return wpiutil.log.BooleanArrayLogEntry(wpilib.DataLogManager.getLog(), name)
def getBooleanLog(name: str):
return wpiutil.log.BooleanLogEntry(wpilib.DataLogManager.getLog(), name)
def getDoubleArrayLog(name: str):
return wpiutil.log.DoubleArrayLogEntry(wpilib.DataLogManager.getLog(), name)
def getDoubleLog(name: str):
return wpiutil.log.DoubleLogEntry(wpilib.DataLogManager.getLog(), name)
def getFloatArrayLog(name: str):
return wpiutil.log.FloatArrayLogEntry(wpilib.DataLogManager.getLog(), name)
def getFloatLog(name: str):
return wpiutil.log.FloatLogEntry(wpilib.DataLogManager.getLog(), name)
def getIntegerArrayLog(name: str):
return wpiutil.log.IntegerArrayLogEntry(wpilib.DataLogManager.getLog(), name)
def getIntegerLog(name: str):
return wpiutil.log.IntegerLogEntry(wpilib.DataLogManager.getLog(), name)
def getStringArrayLog(name: str):
return wpiutil.log.StringArrayLogEntry(wpilib.DataLogManager.getLog(), name)
def getStringLog(name: str):
return wpiutil.log.StringLogEntry(wpilib.DataLogManager.getLog(), name)
def getStructArrayLog(name: str, type: type):
return wpiutil.log.StructArrayLogEntry(wpilib.DataLogManager.getLog(), name, type)
def getStructLog(name: str, type: type):
return wpiutil.log.StructLogEntry(wpilib.DataLogManager.getLog(), name, type)
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