logger.md

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The Logger and LogPlayback add-ons

1. Logger

The Logger add-on will log every command sent to the build to a text file per communicate() call. It can later read that text file and send those commands to the build. The Logger can be very useful when debugging code.

Add a Logger just like you'd add any other add-on:

from tdw.controller import Controller
from tdw.add_ons.logger import Logger

c = Controller()
logger = Logger(path="log.txt")
c.add_ons.append(logger)
# The logger add-on will log this command.
c.communicate({"$type": "do_nothing"})
# The logger add-on will log this command and generate a log.txt file.
c.communicate({"$type": "terminate"})

• path is the path to the log file. It can be a string or a Path.
• Optionally, you can set overwrite=True in the constructor. If True, and if a log file already exists at path, the log file will be overwritten.
• Optionally, you can set log_commands_in_build=True in the constructor. This will log each list of commands in the Player log.

This controller will add three random objects to the scene and log the commands:

import random
from tdw.controller import Controller
from tdw.tdw_utils import TDWUtils
from tdw.add_ons.logger import Logger

c = Controller()
logger = Logger(path="log.txt")
c.add_ons.append(logger)

commands = [TDWUtils.create_empty_room(12, 12)]
models = ["iron_box", "rh10", "basket_18inx18inx12iin_bamboo", "vase_02"]
x = -2
for i in range(3):
    model_name: str = random.choice(models)
    commands.append(c.get_add_object(model_name=model_name,
                                     object_id=c.get_unique_id(),
                                     position={"x": x, "y": 0, "z": 0}))
    x += 1
c.communicate(commands)
c.communicate({"$type": "terminate"})

2. LogPlayback

The LogPlayback add-on can read a log file of commands and re-send the commands. Combined with Logger, this will let you re-create scenes by playing back exact sequences of lists of commands:

from tdw.controller import Controller
from tdw.add_ons.log_playback import LogPlayback

c = Controller()
log_playback = LogPlayback()
c.add_ons.append(log_playback)
# Load the commands.
log_playback.load(path="log.txt")
# Play back each list of commands.
while len(log_playback.playback) > 0:
    c.communicate([])
c.communicate({"$type": "terminate"})

Note that we are calling c.communicate([]), supplying an empty list. You shouldn't add the playback's commands to this list or else they'll be sent twice. This is because log_playback automatically appends the next list of commands within the communicate() call (just like any other add-on).

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Next: The JsonWriter add-on

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Python API:

• Logger