Removed the express callback which should add the latest block in the…

… TC to the DHT, and made use of the existing listeners_map. Added a wildcard UNIVERSAL_BLOCK_LISTENER key to the aforementioned listeners_map, which stores listeners that are called regardless of the block's type. Also removed the redundant code affected by this change.

ipv8/REST/dht_endpoint.py

@@ -6,13 +6,14 @@
 import json
 import struct
 
-from twisted.internet.defer import inlineCallbacks, returnValue
+from twisted.internet.defer import inlineCallbacks
 from twisted.web import http, resource
 from twisted.web.server import NOT_DONE_YET
 
 from ..dht.community import DHTCommunity, MAX_ENTRY_SIZE
 from ..attestation.trustchain.community import TrustChainCommunity
 from ..dht.discovery import DHTDiscoveryCommunity
+from ..attestation.trustchain.listener import BlockListener
 
 
 class DHTEndpoint(resource.Resource):
@@ -32,12 +33,18 @@ def __init__(self, session):
  self.putChild(b"block", DHTBlockEndpoint(dht_overlays[0], tc_overlays[0]))
 
 
-class DHTBlockEndpoint(resource.Resource):
+class DHTBlockEndpoint(resource.Resource, BlockListener):
  """
  This endpoint is responsible for returning the latest Trustchain block of a peer. Additionally, it ensures
  this peer's latest TC block is available
  """
 
+ def received_block(self, block):
+ self.publish_latest_block()
+
+ def should_sign(self, block):
+ pass
+
  KEY_SUFFIX = b'_BLOCK'
 
  def __init__(self, dht, trustchain):
@@ -48,7 +55,7 @@ def __init__(self, dht, trustchain):
 
  self._hashed_dht_key = sha1(self.trustchain.my_peer.mid + self.KEY_SUFFIX).digest()
 
- trustchain.set_new_block_cb(self.publish_latest_block)
+ trustchain.add_listener(self, [trustchain.UNIVERSAL_BLOCK_LISTENER])
 
  @inlineCallbacks
  def publish_latest_block(self):
@@ -57,7 +64,6 @@ def publish_latest_block(self):
 
  :return:
  """
- # latest_block = self.trustchain.persistence.get_latest(self.trustchain.my_peer.key.pub().key_to_bin())
  latest_block = self.trustchain.persistence.get_latest(self.trustchain.my_peer.public_key.key_to_bin())
 
  if latest_block:

ipv8/attestation/trustchain/community.py

@@ -53,6 +53,7 @@ class TrustChainCommunity(Community):
  "66f0373ca425015cc9fad75b267de0cfb46ed798796058b23e12fc4c42ce9868f1eb7d59cc2023c039"
  "14175ebb9703"))
 
+ UNIVERSAL_BLOCK_LISTENER = 'UNIVERSAL_BLOCK_LISTENER'
  DB_CLASS = TrustChainDB
  DB_NAME = 'trustchain'
  version = b'\x02'
@@ -73,8 +74,6 @@ def __init__(self, *args, **kwargs):
  self.db_cleanup_lc = self.register_task("db_cleanup", LoopingCall(self.do_db_cleanup))
  self.db_cleanup_lc.start(600)
 
- self.new_block_cb = lambda: None
-
  self.decode_map.update({
  chr(1): self.received_half_block,
  chr(2): self.received_crawl_request,
@@ -85,13 +84,6 @@ def __init__(self, *args, **kwargs):
  chr(7): self.received_empty_crawl_response,
  })
 
- def set_new_block_cb(self, f):
- """
- Set the callback for when a new block is added to the DB. The callback should take no arguments and should
- return nothing: [] -> None
- """
- self.new_block_cb = f
-
  def do_db_cleanup(self):
  """
  Cleanup the database if necessary.
@@ -260,7 +252,6 @@ def sign_block(self, peer, public_key=EMPTY_PK, block_type=b'unknown', transacti
 
  if not self.persistence.contains(block):
  self.persistence.add_block(block)
- self.new_block_cb()
  self.notify_listeners(block)
 
  # This is a source block with no counterparty
@@ -352,7 +343,6 @@ def validate_persist_block(self, block):
  pass
  elif not self.persistence.contains(block):
  self.persistence.add_block(block)
- self.new_block_cb()
  self.notify_listeners(block)
 
  return validation
@@ -361,7 +351,12 @@ def notify_listeners(self, block):
  """
  Notify listeners of a specific new block.
  """
- if block.type not in self.listeners_map or self.shutting_down:
+ # Call the listeners associated to the universal block
+ for listener in self.listeners_map[self.UNIVERSAL_BLOCK_LISTENER]:
+ listener.received_block(block)
+
+ # Avoid proceeding any further if the type of the block coincides with the UNIVERSAL_BLOCK_LISTENER
+ if block.type not in self.listeners_map or self.shutting_down or block.type == self.UNIVERSAL_BLOCK_LISTENER:
  return
 
  for listener in self.listeners_map[block.type]: