URI: 
       tblockchain.py: add type annotations - electrum - Electrum Bitcoin wallet
  HTML git clone https://git.parazyd.org/electrum
   DIR Log
   DIR Files
   DIR Refs
   DIR Submodules
       ---
   DIR commit a5b3f809ce00c41bf0387d810c395ff709d09ccb
   DIR parent 014c0d3a41090698b3d3d0c602988ad9bf771f73
  HTML Author: SomberNight <somber.night@protonmail.com>
       Date:   Tue, 11 Sep 2018 22:14:57 +0200
       
       blockchain.py: add type annotations
       
       Diffstat:
         M electrum/blockchain.py              |      93 ++++++++++++++++---------------
       
       1 file changed, 48 insertions(+), 45 deletions(-)
       ---
   DIR diff --git a/electrum/blockchain.py b/electrum/blockchain.py
       t@@ -22,6 +22,7 @@
        # SOFTWARE.
        import os
        import threading
       +from typing import Optional
        
        from . import util
        from .bitcoin import Hash, hash_encode, int_to_hex, rev_hex
       t@@ -38,16 +39,16 @@ class MissingHeader(Exception):
        class InvalidHeader(Exception):
            pass
        
       -def serialize_header(res):
       -    s = int_to_hex(res.get('version'), 4) \
       -        + rev_hex(res.get('prev_block_hash')) \
       -        + rev_hex(res.get('merkle_root')) \
       -        + int_to_hex(int(res.get('timestamp')), 4) \
       -        + int_to_hex(int(res.get('bits')), 4) \
       -        + int_to_hex(int(res.get('nonce')), 4)
       +def serialize_header(header_dict: dict) -> str:
       +    s = int_to_hex(header_dict['version'], 4) \
       +        + rev_hex(header_dict['prev_block_hash']) \
       +        + rev_hex(header_dict['merkle_root']) \
       +        + int_to_hex(int(header_dict['timestamp']), 4) \
       +        + int_to_hex(int(header_dict['bits']), 4) \
       +        + int_to_hex(int(header_dict['nonce']), 4)
            return s
        
       -def deserialize_header(s, height):
       +def deserialize_header(s: bytes, height: int) -> dict:
            if not s:
                raise InvalidHeader('Invalid header: {}'.format(s))
            if len(s) != 80:
       t@@ -63,7 +64,7 @@ def deserialize_header(s, height):
            h['block_height'] = height
            return h
        
       -def hash_header(header):
       +def hash_header(header: dict) -> str:
            if header is None:
                return '0' * 64
            if header.get('prev_block_hash') is None:
       t@@ -90,20 +91,6 @@ def read_blockchains(config):
                    util.print_error("cannot connect", filename)
            return blockchains
        
       -def check_header(header):
       -    if type(header) is not dict:
       -        return False
       -    for b in blockchains.values():
       -        if b.check_header(header):
       -            return b
       -    return False
       -
       -def can_connect(header):
       -    for b in blockchains.values():
       -        if b.can_connect(header):
       -            return b
       -    return False
       -
        
        class Blockchain(util.PrintError):
            """
       t@@ -130,21 +117,21 @@ class Blockchain(util.PrintError):
            def parent(self):
                return blockchains[self.parent_id]
        
       -    def get_max_child(self):
       +    def get_max_child(self) -> Optional[int]:
                children = list(filter(lambda y: y.parent_id==self.forkpoint, blockchains.values()))
                return max([x.forkpoint for x in children]) if children else None
        
       -    def get_forkpoint(self):
       +    def get_forkpoint(self) -> int:
                mc = self.get_max_child()
                return mc if mc is not None else self.forkpoint
        
       -    def get_branch_size(self):
       +    def get_branch_size(self) -> int:
                return self.height() - self.get_forkpoint() + 1
        
       -    def get_name(self):
       +    def get_name(self) -> str:
                return self.get_hash(self.get_forkpoint()).lstrip('00')[0:10]
        
       -    def check_header(self, header):
       +    def check_header(self, header: dict) -> bool:
                header_hash = hash_header(header)
                height = header.get('block_height')
                try:
       t@@ -152,25 +139,25 @@ class Blockchain(util.PrintError):
                except MissingHeader:
                    return False
        
       -    def fork(parent, header):
       +    def fork(parent, header: dict):
                forkpoint = header.get('block_height')
                self = Blockchain(parent.config, forkpoint, parent.forkpoint)
                open(self.path(), 'w+').close()
                self.save_header(header)
                return self
        
       -    def height(self):
       +    def height(self) -> int:
                return self.forkpoint + self.size() - 1
        
       -    def size(self):
       +    def size(self) -> int:
                with self.lock:
                    return self._size
        
       -    def update_size(self):
       +    def update_size(self) -> None:
                p = self.path()
                self._size = os.path.getsize(p)//80 if os.path.exists(p) else 0
        
       -    def verify_header(self, header, prev_hash, target, expected_header_hash=None):
       +    def verify_header(self, header: dict, prev_hash: str, target: int, expected_header_hash: str=None) -> None:
                _hash = hash_header(header)
                if expected_header_hash and expected_header_hash != _hash:
                    raise Exception("hash mismatches with expected: {} vs {}".format(expected_header_hash, _hash))
       t@@ -184,7 +171,7 @@ class Blockchain(util.PrintError):
                if int('0x' + _hash, 16) > target:
                    raise Exception("insufficient proof of work: %s vs target %s" % (int('0x' + _hash, 16), target))
        
       -    def verify_chunk(self, index, data):
       +    def verify_chunk(self, index: int, data: bytes) -> None:
                num = len(data) // 80
                start_height = index * 2016
                prev_hash = self.get_hash(start_height - 1)
       t@@ -206,7 +193,7 @@ class Blockchain(util.PrintError):
                return os.path.join(d, filename)
        
            @with_lock
       -    def save_chunk(self, index, chunk):
       +    def save_chunk(self, index: int, chunk: bytes):
                chunk_within_checkpoint_region = index < len(self.checkpoints)
                # chunks in checkpoint region are the responsibility of the 'main chain'
                if chunk_within_checkpoint_region and self.parent_id is not None:
       t@@ -226,7 +213,7 @@ class Blockchain(util.PrintError):
                self.swap_with_parent()
        
            @with_lock
       -    def swap_with_parent(self):
       +    def swap_with_parent(self) -> None:
                if self.parent_id is None:
                    return
                parent_branch_size = self.parent().height() - self.forkpoint + 1
       t@@ -270,7 +257,7 @@ class Blockchain(util.PrintError):
                else:
                    raise FileNotFoundError('Cannot find headers file but headers_dir is there. Should be at {}'.format(path))
        
       -    def write(self, data, offset, truncate=True):
       +    def write(self, data: bytes, offset: int, truncate: bool=True) -> None:
                filename = self.path()
                with self.lock:
                    self.assert_headers_file_available(filename)
       t@@ -285,7 +272,7 @@ class Blockchain(util.PrintError):
                    self.update_size()
        
            @with_lock
       -    def save_header(self, header):
       +    def save_header(self, header: dict) -> None:
                delta = header.get('block_height') - self.forkpoint
                data = bfh(serialize_header(header))
                # headers are only _appended_ to the end:
       t@@ -294,7 +281,7 @@ class Blockchain(util.PrintError):
                self.write(data, delta*80)
                self.swap_with_parent()
        
       -    def read_header(self, height):
       +    def read_header(self, height: int) -> Optional[dict]:
                assert self.parent_id != self.forkpoint
                if height < 0:
                    return
       t@@ -314,7 +301,7 @@ class Blockchain(util.PrintError):
                    return None
                return deserialize_header(h, height)
        
       -    def get_hash(self, height):
       +    def get_hash(self, height: int) -> str:
                def is_height_checkpoint():
                    within_cp_range = height <= constants.net.max_checkpoint()
                    at_chunk_boundary = (height+1) % 2016 == 0
       t@@ -334,7 +321,7 @@ class Blockchain(util.PrintError):
                        raise MissingHeader(height)
                    return hash_header(header)
        
       -    def get_target(self, index):
       +    def get_target(self, index: int) -> int:
                # compute target from chunk x, used in chunk x+1
                if constants.net.TESTNET:
                    return 0
       t@@ -357,7 +344,7 @@ class Blockchain(util.PrintError):
                new_target = min(MAX_TARGET, (target * nActualTimespan) // nTargetTimespan)
                return new_target
        
       -    def bits_to_target(self, bits):
       +    def bits_to_target(self, bits: int) -> int:
                bitsN = (bits >> 24) & 0xff
                if not (bitsN >= 0x03 and bitsN <= 0x1d):
                    raise Exception("First part of bits should be in [0x03, 0x1d]")
       t@@ -366,7 +353,7 @@ class Blockchain(util.PrintError):
                    raise Exception("Second part of bits should be in [0x8000, 0x7fffff]")
                return bitsBase << (8 * (bitsN-3))
        
       -    def target_to_bits(self, target):
       +    def target_to_bits(self, target: int) -> int:
                c = ("%064x" % target)[2:]
                while c[:2] == '00' and len(c) > 6:
                    c = c[2:]
       t@@ -376,7 +363,7 @@ class Blockchain(util.PrintError):
                    bitsBase >>= 8
                return bitsN << 24 | bitsBase
        
       -    def can_connect(self, header, check_height=True):
       +    def can_connect(self, header: dict, check_height: bool=True) -> bool:
                if header is None:
                    return False
                height = header['block_height']
       t@@ -401,7 +388,7 @@ class Blockchain(util.PrintError):
                    return False
                return True
        
       -    def connect_chunk(self, idx, hexdata):
       +    def connect_chunk(self, idx: int, hexdata: str) -> bool:
                try:
                    data = bfh(hexdata)
                    self.verify_chunk(idx, data)
       t@@ -421,3 +408,19 @@ class Blockchain(util.PrintError):
                    target = self.get_target(index)
                    cp.append((h, target))
                return cp
       +
       +
       +def check_header(header: dict) -> Optional[Blockchain]:
       +    if type(header) is not dict:
       +        return None
       +    for b in blockchains.values():
       +        if b.check_header(header):
       +            return b
       +    return None
       +
       +
       +def can_connect(header: dict) -> Optional[Blockchain]:
       +    for b in blockchains.values():
       +        if b.can_connect(header):
       +            return b
       +    return None