From 19f70d7a1132aefdb2bdb0b3959e52bb7a91bd47 Mon Sep 17 00:00:00 2001
From: Victor Shyba <victor.shyba@gmail.com>
Date: Sun, 31 Jan 2021 17:36:26 -0300
Subject: [PATCH] create changelog trigger

---
 lbry/wallet/server/block_processor.py |  5 -----
 lbry/wallet/server/db/writer.py       | 18 ++++++++++++++++--
 2 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/lbry/wallet/server/block_processor.py b/lbry/wallet/server/block_processor.py
index 6cc3a4a48..14e87cee3 100644
--- a/lbry/wallet/server/block_processor.py
+++ b/lbry/wallet/server/block_processor.py
@@ -164,7 +164,6 @@ class BlockProcessor:
         self.prefetcher = Prefetcher(daemon, env.coin, self.blocks_event)
         self.logger = class_logger(__name__, self.__class__.__name__)
         self.executor = ThreadPoolExecutor(1)
-        self.index_executor = ThreadPoolExecutor(os.cpu_count())
 
         # Meta
         self.next_cache_check = 0
@@ -216,10 +215,6 @@ class BlockProcessor:
         if hprevs == chain:
             start = time.perf_counter()
             await self.run_in_thread_with_lock(self.advance_blocks, blocks)
-            pending = []
-            for height in range(first, first + len(blocks)):
-                pending.append(asyncio.get_event_loop().run_in_executor(self.index_executor, self.db.sql.enqueue_changes, height))
-            await asyncio.gather(*pending)
             await self.db.search_index.sync_queue(self.sql.claim_queue)
             for cache in self.search_cache.values():
                 cache.clear()
diff --git a/lbry/wallet/server/db/writer.py b/lbry/wallet/server/db/writer.py
index d3a44ab72..667364ee7 100644
--- a/lbry/wallet/server/db/writer.py
+++ b/lbry/wallet/server/db/writer.py
@@ -135,6 +135,17 @@ class SQLDB:
         create index if not exists claimtrie_claim_hash_idx on claimtrie (claim_hash);
     """
 
+    CREATE_CHANGELOG_TRIGGER = """
+        create table if not exists changelog (
+            claim_hash bytes primary key
+        );
+        create index if not exists claimtrie_claim_hash_idx on claimtrie (claim_hash);
+        create trigger if not exists claim_changelog after update on claim
+        begin
+            insert or ignore into changelog (claim_hash) values (new.claim_hash);
+        end;
+    """
+
     SEARCH_INDEXES = """
         -- used by any tag clouds
         create index if not exists tag_tag_idx on tag (tag, claim_hash);
@@ -194,6 +205,7 @@ class SQLDB:
         CREATE_SUPPORT_TABLE +
         CREATE_CLAIMTRIE_TABLE +
         CREATE_TAG_TABLE +
+        CREATE_CHANGELOG_TRIGGER +
         CREATE_LANGUAGE_TABLE
     )
 
@@ -806,7 +818,7 @@ class SQLDB:
             f"SELECT claim_hash, normalized FROM claim WHERE expiration_height = {height}"
         )
 
-    def enqueue_changes(self, height):
+    def enqueue_changes(self):
         for claim in self.execute(f"""
         SELECT claimtrie.claim_hash as is_controlling,
                claimtrie.last_take_over_height,
@@ -814,7 +826,7 @@ class SQLDB:
                (select group_concat(language, ' ') from language where language.claim_hash in (claim.claim_hash, claim.reposted_claim_hash)) as languages,
                claim.*
         FROM claim LEFT JOIN claimtrie USING (claim_hash)
-        WHERE claim.height = {height} OR claim.claim_hash in (SELECT claim_hash FROM support WHERE height = {height})
+        WHERE claim.claim_hash in (SELECT claim_hash FROM changelog)
         """):
             claim = claim._asdict()
             id_set = set(filter(None, (claim['claim_hash'], claim['channel_hash'], claim['reposted_claim_hash'])))
@@ -838,6 +850,7 @@ class SQLDB:
             claim['languages'] = claim['languages'].split(' ') if claim['languages'] else []
             if not self.claim_queue.full():
                 self.claim_queue.put_nowait(('update', claim))
+        self.execute("delete from changelog;")
 
     def enqueue_deleted(self, deleted_claims):
         for claim_hash in deleted_claims:
@@ -940,6 +953,7 @@ class SQLDB:
             r(first_sync_finished, self.db.cursor())
             self._fts_synced = True
         r(self.enqueue_deleted, delete_claim_hashes)
+        r(self.enqueue_changes)
 
 
 class LBRYLevelDB(LevelDB):