1 files changed, 59 insertions, 0 deletions
diff --git a/rag/db/document.py b/rag/db/document.py
new file mode 100644
index 0000000..8e4d208
--- /dev/null
+++ b/rag/db/document.py
@@ -0,0 +1,59 @@
+import hashlib
+import os
+from typing import List
+
+import psycopg
+from langchain_core.documents.base import Document
+from loguru import logger as log
+
+TABLES = """
+CREATE TABLE IF NOT EXISTS document (
+        hash text PRIMARY KEY)
+"""
+
+
+class DocumentDB:
+    def __init__(self) -> None:
+        self.conn = psycopg.connect(
+            f"dbname={os.environ['RAG_DB_NAME']} user={os.environ['RAG_DB_USER']}"
+        )
+        self.__configure()
+
+    def close(self):
+        self.conn.close()
+
+    def __configure(self):
+        log.debug("Creating documents table if it does not exist...")
+        with self.conn.cursor() as cur:
+            cur.execute(TABLES)
+            self.conn.commit()
+
+    def __hash(self, chunks: List[Document]) -> str:
+        log.debug("Generating sha256 hash for pdf document")
+        document = str.encode("".join([chunk.page_content for chunk in chunks]))
+        return hashlib.sha256(document).hexdigest()
+
+    def add_document(self, chunks: List[Document]) -> bool:
+        log.debug("Inserting document hash into documents db...")
+        with self.conn.cursor() as cur:
+            hash = self.__hash(chunks)
+            cur.execute(
+                """
+                        SELECT * FROM document 
+                        WHERE
+                        hash = %s
+                        """,
+                (hash,),
+            )
+            exist = cur.fetchone()
+            if exist is None:
+                cur.execute(
+                    """
+                            INSERT INTO document 
+                            (hash) VALUES 
+                            (%s)
+                            """,
+                    (hash,),
+                )
+            self.conn.commit()
+        return exist is not None