chat qa with sources (#1084)

docs/modules/chains/combine_docs_examples/chat_vector_db.ipynb

@@ -216,7 +216,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "908c00e2",
+   "id": "7fb44daa",
    "metadata": {},
    "source": [
     "## Chat Vector DB with `map_reduce`\n",
@@ -226,7 +226,7 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "06d91167",
+   "id": "e53a9d66",
    "metadata": {},
    "outputs": [],
    "source": [
@@ -238,7 +238,7 @@
   {
    "cell_type": "code",
    "execution_count": 9,
-   "id": "1711d3b4",
+   "id": "bf205e35",
    "metadata": {},
    "outputs": [],
    "source": [
@@ -256,7 +256,7 @@
   {
    "cell_type": "code",
    "execution_count": 10,
-   "id": "375b33ef",
+   "id": "78155887",
    "metadata": {},
    "outputs": [],
    "source": [
@@ -268,7 +268,7 @@
   {
    "cell_type": "code",
    "execution_count": 11,
-   "id": "ca48ff74",
+   "id": "e54b5fa2",
    "metadata": {},
    "outputs": [
     {
@@ -286,6 +286,77 @@
     "result['answer']"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "id": "a2fe6b14",
+   "metadata": {},
+   "source": [
+    "## Chat Vector DB with Question Answering with sources\n",
+    "\n",
+    "You can also use this chain with the question answering with sources chain."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 12,
+   "id": "d1058fd2",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "from langchain.chains.qa_with_sources import load_qa_with_sources_chain"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 13,
+   "id": "a6594482",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "llm = OpenAI(temperature=0)\n",
+    "question_generator = LLMChain(llm=llm, prompt=CONDENSE_QUESTION_PROMPT)\n",
+    "doc_chain = load_qa_with_sources_chain(llm, chain_type=\"map_reduce\")\n",
+    "\n",
+    "chain = ChatVectorDBChain(\n",
+    "    vectorstore=vectorstore,\n",
+    "    question_generator=question_generator,\n",
+    "    combine_docs_chain=doc_chain,\n",
+    ")"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 14,
+   "id": "e2badd21",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "chat_history = []\n",
+    "query = \"What did the president say about Ketanji Brown Jackson\"\n",
+    "result = chain({\"question\": query, \"chat_history\": chat_history})"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 16,
+   "id": "edb31fe5",
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "\" The president said that Ketanji Brown Jackson is one of the nation's top legal minds, a former top litigator in private practice, a former federal public defender, from a family of public school educators and police officers, a consensus builder, and has received a broad range of support from the Fraternal Order of Police to former judges appointed by Democrats and Republicans. \\nSOURCES: ../../state_of_the_union.txt\""
+      ]
+     },
+     "execution_count": 16,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "result['answer']"
+   ]
+  },
   {
    "cell_type": "markdown",
    "id": "2324cdc6-98bf-4708-b8cd-02a98b1e5b67",