util.py

import binascii
import os, sys, re, json
from collections import defaultdict
from datetime import datetime
from decimal import Decimal
import traceback
import urllib
import threading
import hmac



import urllib.request, urllib.parse, urllib.error
import queue

def inv_dict(d):
    return {v: k for k, v in d.items()}

def normalize_version(v):
    return [int(x) for x in re.sub(r'(\.0+)*$','', v).split(".")]

class NotEnoughFunds(Exception): pass

class InvalidPassword(Exception):
    def __str__(self):
        return _("Incorrect password")

# Throw this exception to unwind the stack like when an error occurs.
# However unlike other exceptions the user won't be informed.
class UserCancelled(Exception):
    '''An exception that is suppressed from the user'''
    pass

class MyEncoder(json.JSONEncoder):
    def default(self, obj):
        from .transaction import Transaction
        if isinstance(obj, Transaction):
            return obj.as_dict()
        return super(MyEncoder, self).default(obj)

class PrintError(object):
    '''A handy base class'''
    def diagnostic_name(self):
        return self.__class__.__name__

    def print_error(self, *msg):
        print_error("[%s]" % self.diagnostic_name(), *msg)

    def print_msg(self, *msg):
        print_msg("[%s]" % self.diagnostic_name(), *msg)

class ThreadJob(PrintError):
    """A job that is run periodically from a thread's main loop.  run() is
    called from that thread's context.
    """

    def run(self):
        """Called periodically from the thread"""
        pass

class DebugMem(ThreadJob):
    '''A handy class for debugging GC memory leaks'''
    def __init__(self, classes, interval=30):
        self.next_time = 0
        self.classes = classes
        self.interval = interval

    def mem_stats(self):
        import gc
        self.print_error("Start memscan")
        gc.collect()
        objmap = defaultdict(list)
        for obj in gc.get_objects():
            for class_ in self.classes:
                if isinstance(obj, class_):
                    objmap[class_].append(obj)
        for class_, objs in objmap.items():
            self.print_error("%s: %d" % (class_.__name__, len(objs)))
        self.print_error("Finish memscan")

    def run(self):
        if time.time() > self.next_time:
            self.mem_stats()
            self.next_time = time.time() + self.interval

class DaemonThread(threading.Thread, PrintError):
    """ daemon thread that terminates cleanly """

    def __init__(self):
        threading.Thread.__init__(self)
        self.parent_thread = threading.currentThread()
        self.running = False
        self.running_lock = threading.Lock()
        self.job_lock = threading.Lock()
        self.jobs = []

    def add_jobs(self, jobs):
        with self.job_lock:
            self.jobs.extend(jobs)

    def run_jobs(self):
        # Don't let a throwing job disrupt the thread, future runs of
        # itself, or other jobs.  This is useful protection against
        # malformed or malicious server responses
        with self.job_lock:
            for job in self.jobs:
                try:
                    job.run()
                except Exception as e:
                    traceback.print_exc(file=sys.stderr)

    def remove_jobs(self, jobs):
        with self.job_lock:
            for job in jobs:
                self.jobs.remove(job)

    def start(self):
        with self.running_lock:
            self.running = True
        return threading.Thread.start(self)

    def is_running(self):
        with self.running_lock:
            return self.running and self.parent_thread.is_alive()

    def stop(self):
        with self.running_lock:
            self.running = False

    def on_stop(self):
        if 'ANDROID_DATA' in os.environ:
            import jnius
            jnius.detach()
            self.print_error("jnius detach")
        self.print_error("stopped")


# TODO: disable
is_verbose = True
def set_verbosity(b):
    global is_verbose
    is_verbose = b


def print_error(*args):
    if not is_verbose: return
    print_stderr(*args)

def print_stderr(*args):
    args = [str(item) for item in args]
    sys.stderr.write(" ".join(args) + "\n")
    sys.stderr.flush()

def print_msg(*args):
    # Stringify args
    args = [str(item) for item in args]
    sys.stdout.write(" ".join(args) + "\n")
    sys.stdout.flush()

def json_encode(obj):
    try:
        s = json.dumps(obj, sort_keys = True, indent = 4, cls=MyEncoder)
    except TypeError:
        s = repr(obj)
    return s

def json_decode(x):
    try:
        return json.loads(x, parse_float=Decimal)
    except:
        return x


# taken from Django Source Code
def constant_time_compare(val1, val2):
    """Return True if the two strings are equal, False otherwise."""
    return hmac.compare_digest(to_bytes(val1, 'utf8'), to_bytes(val2, 'utf8'))


# decorator that prints execution time
def profiler(func):
    def do_profile(func, args, kw_args):
        n = func.__name__
        t0 = time.time()
        o = func(*args, **kw_args)
        t = time.time() - t0
        print_error("[profiler]", n, "%.4f"%t)
        return o
    return lambda *args, **kw_args: do_profile(func, args, kw_args)


def assert_bytes(*args):
    """
    porting helper, assert args type
    """
    try:
        for x in args:
            assert isinstance(x, (bytes, bytearray))
    except:
        print('assert bytes failed', list(map(type, args)))
        raise


def assert_str(*args):
    """
    porting helper, assert args type
    """
    for x in args:
        assert isinstance(x, str)



def to_string(x, enc):
    if isinstance(x, (bytes, bytearray)):
        return x.decode(enc)
    if isinstance(x, str):
        return x
    else:
        raise TypeError("Not a string or bytes like object")

def to_bytes(something, encoding='utf8'):
    """
    cast string to bytes() like object, but for python2 support it's bytearray copy
    """
    if isinstance(something, bytes):
        return something
    if isinstance(something, str):
        return something.encode(encoding)
    elif isinstance(something, bytearray):
        return bytes(something)
    else:
        raise TypeError("Not a string or bytes like object")


bfh = bytes.fromhex
hfu = binascii.hexlify


def bh2u(x):
    """
    str with hex representation of a bytes-like object

    >>> x = bytes((1, 2, 10))
    >>> bh2u(x)
    '01020A'

    :param x: bytes
    :rtype: str
    """
    return hfu(x).decode('ascii')


def format_satoshis_plain(x, decimal_point = 8):
    """Display a satoshi amount scaled.  Always uses a '.' as a decimal
    point and has no thousands separator"""
    scale_factor = pow(10, decimal_point)
    return "{:.8f}".format(Decimal(x) / scale_factor).rstrip('0').rstrip('.')


def format_satoshis(x, is_diff=False, num_zeros = 0, decimal_point = 8, whitespaces=False):
    from locale import localeconv
    if x is None:
        return 'unknown'
    x = int(x)  # Some callers pass Decimal
    scale_factor = pow (10, decimal_point)
    integer_part = "{:n}".format(int(abs(x) / scale_factor))
    if x < 0:
        integer_part = '-' + integer_part
    elif is_diff:
        integer_part = '+' + integer_part
    dp = localeconv()['decimal_point']
    fract_part = ("{:0" + str(decimal_point) + "}").format(abs(x) % scale_factor)
    fract_part = fract_part.rstrip('0')
    if len(fract_part) < num_zeros:
        fract_part += "0" * (num_zeros - len(fract_part))
    result = integer_part + dp + fract_part
    if whitespaces:
        result += " " * (decimal_point - len(fract_part))
        result = " " * (15 - len(result)) + result
    return result

def timestamp_to_datetime(timestamp):
    try:
        return datetime.fromtimestamp(timestamp)
    except:
        return None

def format_time(timestamp):
    date = timestamp_to_datetime(timestamp)
    return date.isoformat(' ')[:-3] if date else _("Unknown")


# Takes a timestamp and returns a string with the approximation of the age
def age(from_date, since_date = None, target_tz=None, include_seconds=False):
    if from_date is None:
        return "Unknown"

    from_date = datetime.fromtimestamp(from_date)
    if since_date is None:
        since_date = datetime.now(target_tz)

    td = time_difference(from_date - since_date, include_seconds)
    return td + " ago" if from_date < since_date else "in " + td


def time_difference(distance_in_time, include_seconds):
    #distance_in_time = since_date - from_date
    distance_in_seconds = int(round(abs(distance_in_time.days * 86400 + distance_in_time.seconds)))
    distance_in_minutes = int(round(distance_in_seconds/60))

    if distance_in_minutes <= 1:
        if include_seconds:
            for remainder in [5, 10, 20]:
                if distance_in_seconds < remainder:
                    return "less than %s seconds" % remainder
            if distance_in_seconds < 40:
                return "half a minute"
            elif distance_in_seconds < 60:
                return "less than a minute"
            else:
                return "1 minute"
        else:
            if distance_in_minutes == 0:
                return "less than a minute"
            else:
                return "1 minute"
    elif distance_in_minutes < 45:
        return "%s minutes" % distance_in_minutes
    elif distance_in_minutes < 90:
        return "about 1 hour"
    elif distance_in_minutes < 1440:
        return "about %d hours" % (round(distance_in_minutes / 60.0))
    elif distance_in_minutes < 2880:
        return "1 day"
    elif distance_in_minutes < 43220:
        return "%d days" % (round(distance_in_minutes / 1440))
    elif distance_in_minutes < 86400:
        return "about 1 month"
    elif distance_in_minutes < 525600:
        return "%d months" % (round(distance_in_minutes / 43200))
    elif distance_in_minutes < 1051200:
        return "about 1 year"
    else:
        return "over %d years" % (round(distance_in_minutes / 525600))

# Python bug (http://bugs.python.org/issue1927) causes raw_input
# to be redirected improperly between stdin/stderr on Unix systems
#TODO: py3
def raw_input(prompt=None):
    if prompt:
        sys.stdout.write(prompt)
    return builtin_raw_input()

import builtins
builtin_raw_input = builtins.input
builtins.input = raw_input


def parse_json(message):
    # TODO: check \r\n pattern
    n = message.find(b'\n')
    if n==-1:
        return None, message
    try:
        j = json.loads(message[0:n].decode('utf8'))
    except:
        j = None
    return j, message[n+1:]


class timeout(Exception):
    pass

import socket
import json
import ssl
import time


class SocketPipe:
    def __init__(self, socket):
        self.socket = socket
        self.message = b''
        self.set_timeout(0.1)
        self.recv_time = time.time()

    def set_timeout(self, t):
        self.socket.settimeout(t)

    def idle_time(self):
        return time.time() - self.recv_time

    def get(self):
        while True:
            response, self.message = parse_json(self.message)
            if response is not None:
                return response
            try:
                data = self.socket.recv(1024)
            except socket.timeout:
                raise timeout
            except ssl.SSLError:
                raise timeout
            except socket.error as err:
                if err.errno == 60:
                    raise timeout
                elif err.errno in [11, 35, 10035]:
                    print_error("socket errno %d (resource temporarily unavailable)"% err.errno)
                    time.sleep(0.2)
                    raise timeout
                else:
                    print_error("pipe: socket error", err)
                    data = b''
            except:
                traceback.print_exc(file=sys.stderr)
                data = b''

            if not data:  # Connection closed remotely
                return None
            self.message += data
            self.recv_time = time.time()

    def send(self, request):
        out = json.dumps(request) + '\n'
        out = out.encode('utf8')
        self._send(out)

    def send_all(self, requests):
        out = b''.join(map(lambda x: (json.dumps(x) + '\n').encode('utf8'), requests))
        self._send(out)

    def _send(self, out):
        while out:
            try:
                sent = self.socket.send(out)
                out = out[sent:]
            except ssl.SSLError as e:
                print_error("SSLError:", e)
                time.sleep(0.1)
                continue
            except OSError as e:
                print_error("OSError", e)
                time.sleep(0.1)
                continue


class QueuePipe:

    def __init__(self, send_queue=None, get_queue=None):
        self.send_queue = send_queue if send_queue else queue.Queue()
        self.get_queue = get_queue if get_queue else queue.Queue()
        self.set_timeout(0.1)

    def get(self):
        try:
            return self.get_queue.get(timeout=self.timeout)
        except queue.Empty:
            raise timeout

    def get_all(self):
        responses = []
        while True:
            try:
                r = self.get_queue.get_nowait()
                responses.append(r)
            except queue.Empty:
                break
        return responses

    def set_timeout(self, t):
        self.timeout = t

    def send(self, request):
        self.send_queue.put(request)

    def send_all(self, requests):
        for request in requests:
            self.send(request)