wallet/verifier: persist wallet.verified_tx when verifier finishes

Previously verified_tx was only persisted in wallet.stop_threads(), hence only on clean shutdowns.

lib/verifier.py

@@ -31,9 +31,8 @@ class SPV(ThreadJob):
         self.wallet = wallet
         self.network = network
         self.blockchain = network.blockchain()
-        # Keyed by tx hash.  Value is None if the merkle branch was
-        # requested, and the merkle root once it has been verified
-        self.merkle_roots = {}
+        self.merkle_roots = {}  # txid -> merkle root (once it has been verified)
+        self.requested_merkle = set()  # txid set of pending requests
 
     def run(self):
         interface = self.network.interface
@@ -53,12 +52,13 @@ class SPV(ThreadJob):
                     if index < len(blockchain.checkpoints):
                         self.network.request_chunk(interface, index)
                 else:
-                    if tx_hash not in self.merkle_roots:
+                    if (tx_hash not in self.requested_merkle
+                            and tx_hash not in self.merkle_roots):
                         request = ('blockchain.transaction.get_merkle',
                                    [tx_hash, tx_height])
                         self.network.send([request], self.verify_merkle)
                         self.print_error('requested merkle', tx_hash)
-                        self.merkle_roots[tx_hash] = None
+                        self.requested_merkle.add(tx_hash)
 
         if self.network.blockchain() != self.blockchain:
             self.blockchain = self.network.blockchain()
@@ -94,8 +94,15 @@ class SPV(ThreadJob):
             return
         # we passed all the tests
         self.merkle_roots[tx_hash] = merkle_root
+        try:
+            # note: we could pop in the beginning, but then we would request
+            # this proof again in case of verification failure from the same server
+            self.requested_merkle.remove(tx_hash)
+        except KeyError: pass
         self.print_error("verified %s" % tx_hash)
         self.wallet.add_verified_tx(tx_hash, (tx_height, header.get('timestamp'), pos))
+        if self.is_up_to_date() and self.wallet.is_up_to_date():
+            self.wallet.save_verified_tx(write=True)
 
     @classmethod
     def hash_merkle_root(cls, merkle_s, target_hash, pos):
@@ -110,4 +117,14 @@ class SPV(ThreadJob):
         tx_hashes = self.wallet.undo_verifications(self.blockchain, height)
         for tx_hash in tx_hashes:
             self.print_error("redoing", tx_hash)
+            self.remove_spv_proof_for_tx(tx_hash)
+
+    def remove_spv_proof_for_tx(self, tx_hash):
         self.merkle_roots.pop(tx_hash, None)
+        try:
+            self.requested_merkle.remove(tx_hash)
+        except KeyError:
+            pass
+
+    def is_up_to_date(self):
+        return not self.requested_merkle

lib/wallet.py

@@ -222,9 +222,10 @@ class Abstract_Wallet(PrintError):
         self.load_unverified_transactions()
         self.remove_local_transactions_we_dont_have()
 
-        # there is a difference between wallet.up_to_date and interface.is_up_to_date()
-        # interface.is_up_to_date() returns true when all requests have been answered and processed
+        # There is a difference between wallet.up_to_date and network.is_up_to_date().
+        # network.is_up_to_date() returns true when all requests have been answered and processed
         # wallet.up_to_date is true when the wallet is synchronized (stronger requirement)
+        # Neither of them considers the verifier.
         self.up_to_date = False
 
         # save wallet type the first time
@@ -291,6 +292,12 @@ class Abstract_Wallet(PrintError):
             if write:
                 self.storage.write()
 
+    def save_verified_tx(self, write=False):
+        with self.lock:
+            self.storage.put('verified_tx3', self.verified_tx)
+            if write:
+                self.storage.write()
+
     def clear_history(self):
         with self.lock:
             with self.transaction_lock:
@@ -365,6 +372,10 @@ class Abstract_Wallet(PrintError):
             self.up_to_date = up_to_date
         if up_to_date:
             self.save_transactions(write=True)
+            # if the verifier is also up to date, persist that too;
+            # otherwise it will persist its results when it finishes
+            if self.verifier and self.verifier.is_up_to_date():
+                self.save_verified_tx(write=True)
 
     def is_up_to_date(self):
         with self.lock: return self.up_to_date
@@ -445,7 +456,7 @@ class Abstract_Wallet(PrintError):
             with self.lock:
                 self.verified_tx.pop(tx_hash)
             if self.verifier:
-                self.verifier.merkle_roots.pop(tx_hash, None)
+                self.verifier.remove_spv_proof_for_tx(tx_hash)
 
         # tx will be verified only if height > 0
         if tx_hash not in self.verified_tx:
@@ -965,7 +976,7 @@ class Abstract_Wallet(PrintError):
                     self.unverified_tx.pop(tx_hash, None)
                     self.verified_tx.pop(tx_hash, None)
                     if self.verifier:
-                        self.verifier.merkle_roots.pop(tx_hash, None)
+                        self.verifier.remove_spv_proof_for_tx(tx_hash)
                     # but remove completely if not is_mine
                     if self.txi[tx_hash] == {}:
                         # FIXME the test here should be for "not all is_mine"; cannot detect conflict in some cases
@@ -1322,8 +1333,7 @@ class Abstract_Wallet(PrintError):
             # remain so they will be GC-ed
             self.storage.put('stored_height', self.get_local_height())
         self.save_transactions()
-        with self.lock:
-            self.storage.put('verified_tx3', self.verified_tx)
+        self.save_verified_tx()
         self.storage.write()
 
     def wait_until_synchronized(self, callback=None):