logger.py

"""
This project was developed by Rocky Duan, Peter Chen, Pieter Abbeel for the Berkeley Deep RL Bootcamp, August 2017. Bootcamp website with slides and lecture videos: https://sites.google.com/view/deep-rl-bootcamp/.

Code adapted from OpenAI Baselines: https://github.com/openai/baselines

Copyright 2017 Deep RL Bootcamp Organizers.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
"""


import datetime
from collections import OrderedDict
import os
import sys
import shutil
import os.path as osp
import json

import dateutil.tz

LOG_OUTPUT_FORMATS = ['stdout', 'log', 'json']

DEBUG = 10
INFO = 20
WARN = 30
ERROR = 40

DISABLED = 50


class OutputFormat(object):
    def writekvs(self, kvs):
        """
        Write key-value pairs
        """
        raise NotImplementedError

    def writeseq(self, args):
        """
        Write a sequence of other data (e.g. a logging message)
        """
        pass

    def close(self):
        return


class HumanOutputFormat(OutputFormat):
    def __init__(self, file):
        self.file = file

    def writekvs(self, kvs):
        # Create strings for printing
        key2str = OrderedDict()
        for (key, val) in kvs.items():
            valstr = '%-8.5g' % (val,) if hasattr(val, '__float__') else val
            key2str[self._truncate(key)] = self._truncate(valstr)

        # Find max widths
        keywidth = max(map(len, key2str.keys()))
        valwidth = max(map(len, key2str.values()))

        # Write out the data
        dashes = '-' * (keywidth + valwidth + 7)
        lines = [dashes]
        for (key, val) in key2str.items():
            lines.append('| %s%s | %s%s |' % (
                key,
                ' ' * (keywidth - len(key)),
                val,
                ' ' * (valwidth - len(val)),
            ))
        lines.append(dashes)
        self.file.write('\n'.join(lines) + '\n')

        # Flush the output to the file
        self.file.flush()

    def _truncate(self, s):
        return s[:20] + '...' if len(s) > 23 else s

    def writeseq(self, args):
        for arg in args:
            self.file.write(arg)
        self.file.write('\n')
        self.file.flush()


class JSONOutputFormat(OutputFormat):
    def __init__(self, file):
        self.file = file

    def writekvs(self, kvs):
        for k, v in kvs.items():
            if hasattr(v, 'dtype'):
                v = v.tolist()
                kvs[k] = float(v)
        self.file.write(json.dumps(kvs) + '\n')
        self.file.flush()


def make_output_format(format, ev_dir):
    os.makedirs(ev_dir, exist_ok=True)
    if format == 'stdout':
        return HumanOutputFormat(sys.stdout)
    elif format == 'log':
        log_file = open(osp.join(ev_dir, 'log.txt'), 'at')
        return HumanOutputFormat(log_file)
    elif format == 'json':
        json_file = open(osp.join(ev_dir, 'progress.json'), 'at')
        return JSONOutputFormat(json_file)
    else:
        raise ValueError('Unknown format specified: %s' % (format,))


# ================================================================
# API
# ================================================================


def logkv(key, val):
    """
    Log a value of some diagnostic
    Call this once for each diagnostic quantity, each iteration
    """
    Logger.CURRENT.logkv(key, val)


def dumpkvs():
    """
    Write all of the diagnostics from the current iteration

    level: int. (see old_logger.py docs) If the global logger level is higher than
                the level argument here, don't print to stdout.
    """
    Logger.CURRENT.dumpkvs()


# for backwards compatibility
record_tabular = logkv
dump_tabular = dumpkvs


def log(*args, level=INFO):
    """
    Write the sequence of args, with no separators, to the console and output files (if you've configured an output file).
    """
    Logger.CURRENT.log(*args, level=level)


def debug(*args):
    log(*args, level=DEBUG)


def info(*args):
    log(*args, level=INFO)


def warn(*args):
    log(*args, level=WARN)


def error(*args):
    log(*args, level=ERROR)


def set_level(level):
    """
    Set logging threshold on current logger.
    """
    Logger.CURRENT.set_level(level)


def get_level():
    """
    Set logging threshold on current logger.
    """
    return Logger.CURRENT.level


def get_dir():
    """
    Get directory that log files are being written to.
    will be None if there is no output directory (i.e., if you didn't call start)
    """
    return Logger.CURRENT.get_dir()


def get_expt_dir():
    sys.stderr.write(
        "get_expt_dir() is Deprecated. Switch to get_dir() [%s]\n" % (get_dir(),))
    return get_dir()


# ================================================================
# Backend
# ================================================================


class Logger(object):
    # A logger with no output files. (See right below class definition)
    DEFAULT = None
    # So that you can still log to the terminal without setting up any output files
    CURRENT = None  # Current logger being used by the free functions above

    def __init__(self, dir, output_formats):
        self.name2val = OrderedDict()  # values this iteration
        self.level = INFO
        self.dir = dir
        self.output_formats = output_formats

    # Logging API, forwarded
    # ----------------------------------------
    def logkv(self, key, val):
        self.name2val[key] = val

    def dumpkvs(self):
        for fmt in self.output_formats:
            fmt.writekvs(self.name2val)
        self.name2val.clear()

    def log(self, *args, level=INFO):
        now = datetime.datetime.now(dateutil.tz.tzlocal())
        timestamp = now.strftime('[%Y-%m-%d %H:%M:%S.%f %Z] ')
        if self.level <= level:
            self._do_log((timestamp,) + args)

    # Configuration
    # ----------------------------------------
    def set_level(self, level):
        self.level = level

    def get_dir(self):
        return self.dir

    def close(self):
        for fmt in self.output_formats:
            fmt.close()

    # Misc
    # ----------------------------------------
    def _do_log(self, args):
        for fmt in self.output_formats:
            fmt.writeseq(args)


# ================================================================

Logger.DEFAULT = Logger(
    output_formats=[HumanOutputFormat(sys.stdout)], dir=None)
Logger.CURRENT = Logger.DEFAULT


class session(object):
    """
    Context manager that sets up the loggers for an experiment.
    """

    CURRENT = None  # Set to a LoggerContext object using enter/exit or context manager

    def __init__(self, dir, format_strs=None):
        self.dir = dir
        if format_strs is None:
            format_strs = LOG_OUTPUT_FORMATS
        output_formats = [make_output_format(f, dir) for f in format_strs]
        Logger.CURRENT = Logger(dir=dir, output_formats=output_formats)

    def __enter__(self):
        os.makedirs(self.evaluation_dir(), exist_ok=True)
        output_formats = [make_output_format(
            f, self.evaluation_dir()) for f in LOG_OUTPUT_FORMATS]
        Logger.CURRENT = Logger(dir=self.dir, output_formats=output_formats)

    def __exit__(self, *args):
        Logger.CURRENT.close()
        Logger.CURRENT = Logger.DEFAULT

    def evaluation_dir(self):
        return self.dir


# ================================================================


def _demo():
    info("hi")
    debug("shouldn't appear")
    set_level(DEBUG)
    debug("should appear")
    dir = "/tmp/testlogging"
    if os.path.exists(dir):
        shutil.rmtree(dir)
    with session(dir=dir):
        record_tabular("a", 3)
        record_tabular("b", 2.5)
        dump_tabular()
        record_tabular("b", -2.5)
        record_tabular("a", 5.5)
        dump_tabular()
        info("^^^ should see a = 5.5")

    record_tabular("b", -2.5)
    dump_tabular()

    record_tabular("a", "longasslongasslongasslongasslongasslongassvalue")
    dump_tabular()


if __name__ == "__main__":
    _demo()