TEMPLATES Add rag-opensearch template (#13501)

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Adding rag-opensearch template.

---------

Signed-off-by: kalyanr <kalyan.ben10@live.com>
Co-authored-by: Erick Friis <erick@langchain.dev>

templates/rag-opensearch/dummy_index_setup.py

@@ -0,0 +1,60 @@
+import os
+
+from openai import OpenAI
+from opensearchpy import OpenSearch
+
+OPENAI_API_KEY = os.getenv("OPENAI_API_KEY")
+OPENSEARCH_URL = os.getenv("OPENSEARCH_URL", "https://localhost:9200")
+OPENSEARCH_USERNAME = os.getenv("OPENSEARCH_USERNAME", "admin")
+OPENSEARCH_PASSWORD = os.getenv("OPENSEARCH_PASSWORD", "admin")
+OPENSEARCH_INDEX_NAME = os.getenv("OPENSEARCH_INDEX_NAME", "langchain-test")
+
+with open("dummy_data.txt") as f:
+    docs = [line.strip() for line in f.readlines()]
+
+
+client_oai = OpenAI(api_key=OPENAI_API_KEY)
+
+
+client = OpenSearch(
+    hosts=[OPENSEARCH_URL],
+    http_auth=(OPENSEARCH_USERNAME, OPENSEARCH_PASSWORD),
+    use_ssl=True,
+    verify_certs=False,
+)
+
+# Define the index settings and mappings
+index_settings = {
+    "settings": {
+        "index": {"knn": True, "number_of_shards": 1, "number_of_replicas": 0}
+    },
+    "mappings": {
+        "properties": {
+            "vector_field": {
+                "type": "knn_vector",
+                "dimension": 1536,
+                "method": {"name": "hnsw", "space_type": "l2", "engine": "faiss"},
+            }
+        }
+    },
+}
+
+response = client.indices.create(index=OPENSEARCH_INDEX_NAME, body=index_settings)
+
+print(response)
+
+
+# Insert docs
+
+
+for each in docs:
+    res = client_oai.embeddings.create(input=each, model="text-embedding-ada-002")
+
+    document = {
+        "vector_field": res.data[0].embedding,
+        "text": each,
+    }
+
+    response = client.index(index=OPENSEARCH_INDEX_NAME, body=document, refresh=True)
+
+    print(response)