From b61d319e02cdd75322b91b6db79acc18a2865702 Mon Sep 17 00:00:00 2001
From: Raj Mehta <rajmehta231@gmail.com>
Date: Mon, 2 Sep 2024 11:30:38 -0700
Subject: [PATCH 01/11] Document Date Reranker

---
 langchain/src/retrievers/recency_ranked.ts    | 66 +++++++++++++++++++
 .../retrievers/tests/recency_ranked.test.ts   | 40 +++++++++++
 2 files changed, 106 insertions(+)
 create mode 100644 langchain/src/retrievers/recency_ranked.ts
 create mode 100644 langchain/src/retrievers/tests/recency_ranked.test.ts

diff --git a/langchain/src/retrievers/recency_ranked.ts b/langchain/src/retrievers/recency_ranked.ts
new file mode 100644
index 000000000000..5f68cd61d5d3
--- /dev/null
+++ b/langchain/src/retrievers/recency_ranked.ts
@@ -0,0 +1,66 @@
+import { BaseRetriever } from "@langchain/core/retrievers";
+import { VectorStoreInterface } from "@langchain/core/vectorstores";
+import { Document } from "@langchain/core/documents";
+
+export interface RecencyRankedRetrieverConfig {
+  vectorStore: VectorStoreInterface;
+  k: number;
+  recencyWeight?: number;
+}
+
+export class RecencyRankedRetriever extends BaseRetriever {
+  static lc_name() {
+    return "RecencyRankedRetriever";
+  }
+
+  lc_namespace = ["langchain", "retrievers", "recency_ranked"];
+  
+  private vectorStore: VectorStoreInterface;
+
+  private k: number;
+
+  private recencyWeight: number;
+
+  constructor(config: RecencyRankedRetrieverConfig) {
+    super();
+    this.vectorStore = config.vectorStore;
+    this.k = config.k;
+    this.recencyWeight = config.recencyWeight ?? 0.3;
+  }
+
+  async getRelevantDocuments(query: string): Promise<Document[]> {
+    const relevantDocs = await this.vectorStore.similaritySearchWithScore(query, 15);
+    const rerankedDocs = this.recentDocumentRanker(relevantDocs, this.k, this.recencyWeight);
+    return rerankedDocs.map(([doc, _]) => doc);
+  }
+
+  private recentDocumentRanker(
+    documents: [Document, number][],
+    topK: number,
+    recencyWeight: number
+  ): [Document, number][] {
+    if (documents.length === 0) return [];
+
+    const oldestDate = Math.min(
+      ...documents.map(([doc, _]) => doc.metadata.date.getTime())
+    );
+    const newestDate = Math.max(
+      ...documents.map(([doc, _]) => doc.metadata.date.getTime())
+    );
+    const dateRange = newestDate - oldestDate;
+
+    const rerankedDocuments = documents
+      .map(([doc, score]): [Document, number] => {
+        const normalizedRecency =
+          dateRange > 0
+            ? (doc.metadata.date.getTime() - oldestDate) / dateRange
+            : 1;
+        const adjustedScore =
+          (1 - recencyWeight) * score + recencyWeight * normalizedRecency;
+        return [doc, adjustedScore];
+      })
+      .sort((a, b) => b[1] - a[1]);
+
+    return rerankedDocuments.slice(0, topK);
+  }
+}
\ No newline at end of file
diff --git a/langchain/src/retrievers/tests/recency_ranked.test.ts b/langchain/src/retrievers/tests/recency_ranked.test.ts
new file mode 100644
index 000000000000..13bf6cc435b4
--- /dev/null
+++ b/langchain/src/retrievers/tests/recency_ranked.test.ts
@@ -0,0 +1,40 @@
+import { expect, test } from "@jest/globals";
+import { Document } from "@langchain/core/documents";
+import { FakeEmbeddings } from "@langchain/core/utils/testing";
+import { MemoryVectorStore } from "../../vectorstores/memory.js"
+import { RecencyRankedRetriever } from "../recency_ranked.js";
+
+
+
+test("RecencyRankedRetriever", async () => {
+  const docs = [
+    new Document({
+      pageContent: "A",
+      metadata: { date: new Date("2023-01-01") },
+    }),
+    new Document({
+      pageContent: "B",
+      metadata: { date: new Date("2023-02-01") },
+    }),
+    new Document({
+      pageContent: "C",
+      metadata: { date: new Date("2023-03-01") },
+    }),
+  ];
+
+  const vectorstore = new MemoryVectorStore(new FakeEmbeddings());
+  
+  await vectorstore.addDocuments(docs);
+  
+  const retriever = new RecencyRankedRetriever({
+    vectorStore: vectorstore,
+    k: 2,
+    recencyWeight: 0.99,
+  });
+  
+  const results = await retriever.getRelevantDocuments("test query");
+
+  expect(results).toHaveLength(2);
+  expect(results[0].pageContent).toBe("C");
+  expect(results[1].pageContent).toBe("B");
+});
\ No newline at end of file

From 41a36d72cf424812fe25c496bffde16fd57f3192 Mon Sep 17 00:00:00 2001
From: Raj Mehta <rajmehta231@gmail.com>
Date: Mon, 2 Sep 2024 11:35:01 -0700
Subject: [PATCH 02/11] Revert "Document Date Reranker"

This reverts commit b61d319e02cdd75322b91b6db79acc18a2865702.
---
 langchain/src/retrievers/recency_ranked.ts    | 66 -------------------
 .../retrievers/tests/recency_ranked.test.ts   | 40 -----------
 2 files changed, 106 deletions(-)
 delete mode 100644 langchain/src/retrievers/recency_ranked.ts
 delete mode 100644 langchain/src/retrievers/tests/recency_ranked.test.ts

diff --git a/langchain/src/retrievers/recency_ranked.ts b/langchain/src/retrievers/recency_ranked.ts
deleted file mode 100644
index 5f68cd61d5d3..000000000000
--- a/langchain/src/retrievers/recency_ranked.ts
+++ /dev/null
@@ -1,66 +0,0 @@
-import { BaseRetriever } from "@langchain/core/retrievers";
-import { VectorStoreInterface } from "@langchain/core/vectorstores";
-import { Document } from "@langchain/core/documents";
-
-export interface RecencyRankedRetrieverConfig {
-  vectorStore: VectorStoreInterface;
-  k: number;
-  recencyWeight?: number;
-}
-
-export class RecencyRankedRetriever extends BaseRetriever {
-  static lc_name() {
-    return "RecencyRankedRetriever";
-  }
-
-  lc_namespace = ["langchain", "retrievers", "recency_ranked"];
-  
-  private vectorStore: VectorStoreInterface;
-
-  private k: number;
-
-  private recencyWeight: number;
-
-  constructor(config: RecencyRankedRetrieverConfig) {
-    super();
-    this.vectorStore = config.vectorStore;
-    this.k = config.k;
-    this.recencyWeight = config.recencyWeight ?? 0.3;
-  }
-
-  async getRelevantDocuments(query: string): Promise<Document[]> {
-    const relevantDocs = await this.vectorStore.similaritySearchWithScore(query, 15);
-    const rerankedDocs = this.recentDocumentRanker(relevantDocs, this.k, this.recencyWeight);
-    return rerankedDocs.map(([doc, _]) => doc);
-  }
-
-  private recentDocumentRanker(
-    documents: [Document, number][],
-    topK: number,
-    recencyWeight: number
-  ): [Document, number][] {
-    if (documents.length === 0) return [];
-
-    const oldestDate = Math.min(
-      ...documents.map(([doc, _]) => doc.metadata.date.getTime())
-    );
-    const newestDate = Math.max(
-      ...documents.map(([doc, _]) => doc.metadata.date.getTime())
-    );
-    const dateRange = newestDate - oldestDate;
-
-    const rerankedDocuments = documents
-      .map(([doc, score]): [Document, number] => {
-        const normalizedRecency =
-          dateRange > 0
-            ? (doc.metadata.date.getTime() - oldestDate) / dateRange
-            : 1;
-        const adjustedScore =
-          (1 - recencyWeight) * score + recencyWeight * normalizedRecency;
-        return [doc, adjustedScore];
-      })
-      .sort((a, b) => b[1] - a[1]);
-
-    return rerankedDocuments.slice(0, topK);
-  }
-}
\ No newline at end of file
diff --git a/langchain/src/retrievers/tests/recency_ranked.test.ts b/langchain/src/retrievers/tests/recency_ranked.test.ts
deleted file mode 100644
index 13bf6cc435b4..000000000000
--- a/langchain/src/retrievers/tests/recency_ranked.test.ts
+++ /dev/null
@@ -1,40 +0,0 @@
-import { expect, test } from "@jest/globals";
-import { Document } from "@langchain/core/documents";
-import { FakeEmbeddings } from "@langchain/core/utils/testing";
-import { MemoryVectorStore } from "../../vectorstores/memory.js"
-import { RecencyRankedRetriever } from "../recency_ranked.js";
-
-
-
-test("RecencyRankedRetriever", async () => {
-  const docs = [
-    new Document({
-      pageContent: "A",
-      metadata: { date: new Date("2023-01-01") },
-    }),
-    new Document({
-      pageContent: "B",
-      metadata: { date: new Date("2023-02-01") },
-    }),
-    new Document({
-      pageContent: "C",
-      metadata: { date: new Date("2023-03-01") },
-    }),
-  ];
-
-  const vectorstore = new MemoryVectorStore(new FakeEmbeddings());
-  
-  await vectorstore.addDocuments(docs);
-  
-  const retriever = new RecencyRankedRetriever({
-    vectorStore: vectorstore,
-    k: 2,
-    recencyWeight: 0.99,
-  });
-  
-  const results = await retriever.getRelevantDocuments("test query");
-
-  expect(results).toHaveLength(2);
-  expect(results[0].pageContent).toBe("C");
-  expect(results[1].pageContent).toBe("B");
-});
\ No newline at end of file

From d904ce68e5cbeea9a10f2812393fa21e2c44dc56 Mon Sep 17 00:00:00 2001
From: Raj Mehta <rajmehta231@gmail.com>
Date: Sun, 8 Sep 2024 18:13:20 -0700
Subject: [PATCH 03/11] bm25 search implementation

---
 langchain/package.json                        |  1 +
 langchain/src/retrievers/bm25_retriever.ts    | 61 +++++++++++++++++++
 .../retrievers/tests/bm25_retriever.test.ts   | 26 ++++++++
 libs/langchain-community/package.json         |  1 +
 yarn.lock                                     |  9 +++
 5 files changed, 98 insertions(+)
 create mode 100644 langchain/src/retrievers/bm25_retriever.ts
 create mode 100644 langchain/src/retrievers/tests/bm25_retriever.test.ts

diff --git a/langchain/package.json b/langchain/package.json
index 3465af3054fe..2058722452d5 100644
--- a/langchain/package.json
+++ b/langchain/package.json
@@ -934,6 +934,7 @@
     "js-yaml": "^4.1.0",
     "jsonpointer": "^5.0.1",
     "langsmith": "~0.1.40",
+    "okapibm25": "^1.4.0",
     "openapi-types": "^12.1.3",
     "p-retry": "4",
     "uuid": "^10.0.0",
diff --git a/langchain/src/retrievers/bm25_retriever.ts b/langchain/src/retrievers/bm25_retriever.ts
new file mode 100644
index 000000000000..0adc557a00b4
--- /dev/null
+++ b/langchain/src/retrievers/bm25_retriever.ts
@@ -0,0 +1,61 @@
+import BM25 from "okapibm25";
+import { BaseRetriever } from "@langchain/core/retrievers";
+import { Document } from "@langchain/core/documents";
+
+export type BM25RetrieverOptions = {
+  docs: Document[];
+  k: number;
+  preprocessFunc: (text: string) => string[];
+};
+
+/**
+ * A retriever that uses the BM25 algorithm to rank documents based on their
+ * similarity to a query. It uses the okapibm25 package for BM25 scoring.
+ * The k parameter determines the number of documents to return for each query.
+ */
+export class BM25Retriever extends BaseRetriever {
+  static lc_name() {
+    return "BM25Retriever";
+  }
+  
+  lc_namespace = ["langchain", "retrievers", "bm25_retriever"];
+  
+  static fromDocuments(
+    documents: Document[],
+    options: Omit<BM25RetrieverOptions, "docs">
+  ) {
+    return new this({ ...options, docs: documents });
+  }
+
+  docs: Document[];
+
+  k: number;
+  
+  preprocessFunc: (text: string) => string[];
+
+  constructor(options: BM25RetrieverOptions) {
+    super();
+    this.docs = options.docs;
+    this.k = options.k;
+    this.preprocessFunc = options.preprocessFunc;
+  }
+
+  async _getRelevantDocuments(query: string) {
+    const processedQuery = this.preprocessFunc(query);
+    const documents = this.docs.map(doc => doc.pageContent);
+    const scores = BM25.default(documents, processedQuery) as number[];
+    
+    const scoredDocs = this.docs.map((doc, index) => ({
+      document: doc,
+      score: scores[index],
+    }));
+    
+    scoredDocs.sort((a, b) => b.score - a.score);
+    
+    return scoredDocs.slice(0, this.k).map(item => item.document);
+  }
+
+  async invoke(input: string): Promise<Document[]> {
+    return this._getRelevantDocuments(input);
+  }
+}
diff --git a/langchain/src/retrievers/tests/bm25_retriever.test.ts b/langchain/src/retrievers/tests/bm25_retriever.test.ts
new file mode 100644
index 000000000000..e2ca3185ab62
--- /dev/null
+++ b/langchain/src/retrievers/tests/bm25_retriever.test.ts
@@ -0,0 +1,26 @@
+import { expect, test } from "@jest/globals";
+import { Document } from "@langchain/core/documents";
+import { BM25Retriever } from "../bm25_retriever.js";
+
+test("BM25Retriever", async () => {
+  const docs = [
+    new Document({
+      pageContent: "The quick brown fox jumps over the lazy dog",
+    }),
+    new Document({
+      pageContent: "A lazy dog sleeps all day",
+    }),
+    new Document({
+      pageContent: "The brown fox is quick and clever",
+    }),
+  ];
+
+  const retriever = BM25Retriever.fromDocuments(docs, {
+    k: 2,
+    preprocessFunc: (text: string) => text.toLowerCase().split(/\s+/),
+  });
+  const results = await retriever.invoke("the fox and the dog");
+
+  expect(results).toHaveLength(2);
+  expect(results[0].pageContent).toBe("The quick brown fox jumps over the lazy dog");
+});
diff --git a/libs/langchain-community/package.json b/libs/langchain-community/package.json
index 767540e6f2fd..efbad8decb6c 100644
--- a/libs/langchain-community/package.json
+++ b/libs/langchain-community/package.json
@@ -43,6 +43,7 @@
     "js-yaml": "^4.1.0",
     "langchain": "~0.2.3",
     "langsmith": "~0.1.30",
+    "okapibm25": "^1.4.0",
     "uuid": "^10.0.0",
     "zod": "^3.22.3",
     "zod-to-json-schema": "^3.22.5"
diff --git a/yarn.lock b/yarn.lock
index 52ec639319f4..a8ab2849ac31 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -11294,6 +11294,7 @@ __metadata:
     node-llama-cpp: 2.7.3
     notion-to-md: ^3.1.0
     officeparser: ^4.0.4
+    okapibm25: ^1.4.0
     pdf-parse: 1.1.1
     pg: ^8.11.0
     pg-copy-streams: ^6.0.5
@@ -32230,6 +32231,7 @@ __metadata:
     node-llama-cpp: 2.7.3
     notion-to-md: ^3.1.0
     officeparser: ^4.0.4
+    okapibm25: ^1.4.0
     openai: ^4.41.1
     openapi-types: ^12.1.3
     p-retry: 4
@@ -35005,6 +35007,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"okapibm25@npm:^1.4.0":
+  version: 1.4.0
+  resolution: "okapibm25@npm:1.4.0"
+  checksum: 8f513ef7a05d78fc7a32d19cfbf44405c8164ddab27431f80516c8a9e00ed9b9f2a3bdbdc11633d3c0611b97f0a86b1f90bd84f6e0b0eb8424a856b34a9fd3de
+  languageName: node
+  linkType: hard
+
 "ollama@npm:^0.5.6":
   version: 0.5.6
   resolution: "ollama@npm:0.5.6"

From a861f985c387abab3fe36a5a824a0aeb36b68ee7 Mon Sep 17 00:00:00 2001
From: Raj Mehta <rajmehta231@gmail.com>
Date: Mon, 9 Sep 2024 08:25:10 -0700
Subject: [PATCH 04/11] fixed retriever input args

---
 langchain/src/retrievers/bm25_retriever.ts            | 8 ++++----
 langchain/src/retrievers/tests/bm25_retriever.test.ts | 1 -
 2 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/langchain/src/retrievers/bm25_retriever.ts b/langchain/src/retrievers/bm25_retriever.ts
index 0adc557a00b4..52b76602c2d6 100644
--- a/langchain/src/retrievers/bm25_retriever.ts
+++ b/langchain/src/retrievers/bm25_retriever.ts
@@ -5,7 +5,6 @@ import { Document } from "@langchain/core/documents";
 export type BM25RetrieverOptions = {
   docs: Document[];
   k: number;
-  preprocessFunc: (text: string) => string[];
 };
 
 /**
@@ -31,13 +30,14 @@ export class BM25Retriever extends BaseRetriever {
 
   k: number;
   
-  preprocessFunc: (text: string) => string[];
-
   constructor(options: BM25RetrieverOptions) {
     super();
     this.docs = options.docs;
     this.k = options.k;
-    this.preprocessFunc = options.preprocessFunc;
+  }
+
+  private preprocessFunc(text: string): string[] {
+    return text.toLowerCase().split(/\s+/);
   }
 
   async _getRelevantDocuments(query: string) {
diff --git a/langchain/src/retrievers/tests/bm25_retriever.test.ts b/langchain/src/retrievers/tests/bm25_retriever.test.ts
index e2ca3185ab62..495e9cb079d8 100644
--- a/langchain/src/retrievers/tests/bm25_retriever.test.ts
+++ b/langchain/src/retrievers/tests/bm25_retriever.test.ts
@@ -17,7 +17,6 @@ test("BM25Retriever", async () => {
 
   const retriever = BM25Retriever.fromDocuments(docs, {
     k: 2,
-    preprocessFunc: (text: string) => text.toLowerCase().split(/\s+/),
   });
   const results = await retriever.invoke("the fox and the dog");
 

From 696de7a237014bece04196a52e738323fc988358 Mon Sep 17 00:00:00 2001
From: jacoblee93 <jacoblee93@gmail.com>
Date: Tue, 10 Sep 2024 14:12:09 -0700
Subject: [PATCH 05/11] Update dep

---
 langchain/package.json |  6 +++++-
 yarn.lock              | 12 +++++++++++-
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/langchain/package.json b/langchain/package.json
index 2058722452d5..4fb8016571ca 100644
--- a/langchain/package.json
+++ b/langchain/package.json
@@ -664,6 +664,7 @@
     "node-llama-cpp": "2.7.3",
     "notion-to-md": "^3.1.0",
     "officeparser": "^4.0.4",
+    "okapibm25": "^1.4.1",
     "openai": "^4.41.1",
     "pdf-parse": "1.1.1",
     "peggy": "^3.0.2",
@@ -731,6 +732,7 @@
     "node-llama-cpp": "*",
     "notion-to-md": "*",
     "officeparser": "*",
+    "okapibm25": "^1.4.1",
     "pdf-parse": "*",
     "peggy": "^3.0.2",
     "playwright": "*",
@@ -882,6 +884,9 @@
     "officeparser": {
       "optional": true
     },
+    "okapibm25": {
+      "optional": true
+    },
     "pdf-parse": {
       "optional": true
     },
@@ -934,7 +939,6 @@
     "js-yaml": "^4.1.0",
     "jsonpointer": "^5.0.1",
     "langsmith": "~0.1.40",
-    "okapibm25": "^1.4.0",
     "openapi-types": "^12.1.3",
     "p-retry": "4",
     "uuid": "^10.0.0",
diff --git a/yarn.lock b/yarn.lock
index a8ab2849ac31..5746accf232c 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -32231,7 +32231,7 @@ __metadata:
     node-llama-cpp: 2.7.3
     notion-to-md: ^3.1.0
     officeparser: ^4.0.4
-    okapibm25: ^1.4.0
+    okapibm25: ^1.4.1
     openai: ^4.41.1
     openapi-types: ^12.1.3
     p-retry: 4
@@ -32304,6 +32304,7 @@ __metadata:
     node-llama-cpp: "*"
     notion-to-md: "*"
     officeparser: "*"
+    okapibm25: ^1.4.1
     pdf-parse: "*"
     peggy: ^3.0.2
     playwright: "*"
@@ -32409,6 +32410,8 @@ __metadata:
       optional: true
     officeparser:
       optional: true
+    okapibm25:
+      optional: true
     pdf-parse:
       optional: true
     peggy:
@@ -35014,6 +35017,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"okapibm25@npm:^1.4.1":
+  version: 1.4.1
+  resolution: "okapibm25@npm:1.4.1"
+  checksum: f619b8888fa983861116f2fd4f2896411d157a75c5ae79d81fd9322821d274f127e0199e0f0b93961c49b6f31b710723ffd893a77820bdd0e52c859c2cbcb594
+  languageName: node
+  linkType: hard
+
 "ollama@npm:^0.5.6":
   version: 0.5.6
   resolution: "ollama@npm:0.5.6"

From 42cac713bbd0c5ae2b6cd09e5ec3e15a7faaf78a Mon Sep 17 00:00:00 2001
From: jacoblee93 <jacoblee93@gmail.com>
Date: Tue, 10 Sep 2024 14:32:51 -0700
Subject: [PATCH 06/11] Move to community

---
 langchain/package.json                        |  5 -----
 libs/langchain-community/langchain.config.js  |  2 ++
 libs/langchain-community/package.json         |  5 +++++
 .../src/retrievers/bm25.ts                    | 21 ++++++++++---------
 .../src/retrievers/tests/bm25.test.ts         |  6 ++++--
 yarn.lock                                     | 16 ++++----------
 6 files changed, 26 insertions(+), 29 deletions(-)
 rename langchain/src/retrievers/bm25_retriever.ts => libs/langchain-community/src/retrievers/bm25.ts (78%)
 rename langchain/src/retrievers/tests/bm25_retriever.test.ts => libs/langchain-community/src/retrievers/tests/bm25.test.ts (80%)

diff --git a/langchain/package.json b/langchain/package.json
index 140c5126125f..91c99b175d6e 100644
--- a/langchain/package.json
+++ b/langchain/package.json
@@ -664,7 +664,6 @@
     "node-llama-cpp": "2.7.3",
     "notion-to-md": "^3.1.0",
     "officeparser": "^4.0.4",
-    "okapibm25": "^1.4.1",
     "openai": "^4.41.1",
     "pdf-parse": "1.1.1",
     "peggy": "^3.0.2",
@@ -732,7 +731,6 @@
     "node-llama-cpp": "*",
     "notion-to-md": "*",
     "officeparser": "*",
-    "okapibm25": "^1.4.1",
     "pdf-parse": "*",
     "peggy": "^3.0.2",
     "playwright": "*",
@@ -884,9 +882,6 @@
     "officeparser": {
       "optional": true
     },
-    "okapibm25": {
-      "optional": true
-    },
     "pdf-parse": {
       "optional": true
     },
diff --git a/libs/langchain-community/langchain.config.js b/libs/langchain-community/langchain.config.js
index 3709f58812e7..85ab7194bfb6 100644
--- a/libs/langchain-community/langchain.config.js
+++ b/libs/langchain-community/langchain.config.js
@@ -194,6 +194,7 @@ export const config = {
     // retrievers
     "retrievers/amazon_kendra": "retrievers/amazon_kendra",
     "retrievers/amazon_knowledge_base": "retrievers/amazon_knowledge_base",
+    "retrievers/bm25": "retrievers/bm25",
     "retrievers/chaindesk": "retrievers/chaindesk",
     "retrievers/databerry": "retrievers/databerry",
     "retrievers/dria": "retrievers/dria",
@@ -426,6 +427,7 @@ export const config = {
     "chat_models/zhipuai",
     "retrievers/amazon_kendra",
     "retrievers/amazon_knowledge_base",
+    "retrievers/bm25",
     "retrievers/dria",
     "retrievers/metal",
     "retrievers/supabase",
diff --git a/libs/langchain-community/package.json b/libs/langchain-community/package.json
index 0bf4c1e0607f..b2cf4e39cea9 100644
--- a/libs/langchain-community/package.json
+++ b/libs/langchain-community/package.json
@@ -187,6 +187,7 @@
     "node-llama-cpp": "2.7.3",
     "notion-to-md": "^3.1.0",
     "officeparser": "^4.0.4",
+    "okapibm25": "^1.4.1",
     "pdf-parse": "1.1.1",
     "pg": "^8.11.0",
     "pg-copy-streams": "^6.0.5",
@@ -313,6 +314,7 @@
     "node-llama-cpp": "*",
     "notion-to-md": "^3.1.0",
     "officeparser": "^4.0.4",
+    "okapibm25": "^1.4.1",
     "pdf-parse": "1.1.1",
     "pg": "^8.11.0",
     "pg-copy-streams": "^6.0.5",
@@ -633,6 +635,9 @@
     "officeparser": {
       "optional": true
     },
+    "okapibm25": {
+      "optional": true
+    },
     "pdf-parse": {
       "optional": true
     },
diff --git a/langchain/src/retrievers/bm25_retriever.ts b/libs/langchain-community/src/retrievers/bm25.ts
similarity index 78%
rename from langchain/src/retrievers/bm25_retriever.ts
rename to libs/langchain-community/src/retrievers/bm25.ts
index 52b76602c2d6..48d1562f27cf 100644
--- a/langchain/src/retrievers/bm25_retriever.ts
+++ b/libs/langchain-community/src/retrievers/bm25.ts
@@ -9,16 +9,16 @@ export type BM25RetrieverOptions = {
 
 /**
  * A retriever that uses the BM25 algorithm to rank documents based on their
- * similarity to a query. It uses the okapibm25 package for BM25 scoring.
+ * similarity to a query. It uses the "okapibm25" package for BM25 scoring.
  * The k parameter determines the number of documents to return for each query.
  */
 export class BM25Retriever extends BaseRetriever {
   static lc_name() {
     return "BM25Retriever";
   }
-  
+
   lc_namespace = ["langchain", "retrievers", "bm25_retriever"];
-  
+
   static fromDocuments(
     documents: Document[],
     options: Omit<BM25RetrieverOptions, "docs">
@@ -29,7 +29,7 @@ export class BM25Retriever extends BaseRetriever {
   docs: Document[];
 
   k: number;
-  
+
   constructor(options: BM25RetrieverOptions) {
     super();
     this.docs = options.docs;
@@ -42,17 +42,18 @@ export class BM25Retriever extends BaseRetriever {
 
   async _getRelevantDocuments(query: string) {
     const processedQuery = this.preprocessFunc(query);
-    const documents = this.docs.map(doc => doc.pageContent);
-    const scores = BM25.default(documents, processedQuery) as number[];
-    
+    const documents = this.docs.map((doc) => doc.pageContent);
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    const scores = (BM25 as any).default(documents, processedQuery) as number[];
+
     const scoredDocs = this.docs.map((doc, index) => ({
       document: doc,
       score: scores[index],
     }));
-    
+
     scoredDocs.sort((a, b) => b.score - a.score);
-    
-    return scoredDocs.slice(0, this.k).map(item => item.document);
+
+    return scoredDocs.slice(0, this.k).map((item) => item.document);
   }
 
   async invoke(input: string): Promise<Document[]> {
diff --git a/langchain/src/retrievers/tests/bm25_retriever.test.ts b/libs/langchain-community/src/retrievers/tests/bm25.test.ts
similarity index 80%
rename from langchain/src/retrievers/tests/bm25_retriever.test.ts
rename to libs/langchain-community/src/retrievers/tests/bm25.test.ts
index 495e9cb079d8..bcfe46f940b8 100644
--- a/langchain/src/retrievers/tests/bm25_retriever.test.ts
+++ b/libs/langchain-community/src/retrievers/tests/bm25.test.ts
@@ -1,6 +1,6 @@
 import { expect, test } from "@jest/globals";
 import { Document } from "@langchain/core/documents";
-import { BM25Retriever } from "../bm25_retriever.js";
+import { BM25Retriever } from "../bm25.js";
 
 test("BM25Retriever", async () => {
   const docs = [
@@ -21,5 +21,7 @@ test("BM25Retriever", async () => {
   const results = await retriever.invoke("the fox and the dog");
 
   expect(results).toHaveLength(2);
-  expect(results[0].pageContent).toBe("The quick brown fox jumps over the lazy dog");
+  expect(results[0].pageContent).toBe(
+    "The quick brown fox jumps over the lazy dog"
+  );
 });
diff --git a/yarn.lock b/yarn.lock
index 4bc8c68ba713..721962918d0a 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -11320,7 +11320,7 @@ __metadata:
     node-llama-cpp: 2.7.3
     notion-to-md: ^3.1.0
     officeparser: ^4.0.4
-    okapibm25: ^1.4.0
+    okapibm25: ^1.4.1
     pdf-parse: 1.1.1
     pg: ^8.11.0
     pg-copy-streams: ^6.0.5
@@ -11449,6 +11449,7 @@ __metadata:
     node-llama-cpp: "*"
     notion-to-md: ^3.1.0
     officeparser: ^4.0.4
+    okapibm25: ^1.4.1
     pdf-parse: 1.1.1
     pg: ^8.11.0
     pg-copy-streams: ^6.0.5
@@ -11669,6 +11670,8 @@ __metadata:
       optional: true
     officeparser:
       optional: true
+    okapibm25:
+      optional: true
     pdf-parse:
       optional: true
     pg:
@@ -32272,7 +32275,6 @@ __metadata:
     node-llama-cpp: 2.7.3
     notion-to-md: ^3.1.0
     officeparser: ^4.0.4
-    okapibm25: ^1.4.1
     openai: ^4.41.1
     openapi-types: ^12.1.3
     p-retry: 4
@@ -32345,7 +32347,6 @@ __metadata:
     node-llama-cpp: "*"
     notion-to-md: "*"
     officeparser: "*"
-    okapibm25: ^1.4.1
     pdf-parse: "*"
     peggy: ^3.0.2
     playwright: "*"
@@ -32451,8 +32452,6 @@ __metadata:
       optional: true
     officeparser:
       optional: true
-    okapibm25:
-      optional: true
     pdf-parse:
       optional: true
     peggy:
@@ -35051,13 +35050,6 @@ __metadata:
   languageName: node
   linkType: hard
 
-"okapibm25@npm:^1.4.0":
-  version: 1.4.0
-  resolution: "okapibm25@npm:1.4.0"
-  checksum: 8f513ef7a05d78fc7a32d19cfbf44405c8164ddab27431f80516c8a9e00ed9b9f2a3bdbdc11633d3c0611b97f0a86b1f90bd84f6e0b0eb8424a856b34a9fd3de
-  languageName: node
-  linkType: hard
-
 "okapibm25@npm:^1.4.1":
   version: 1.4.1
   resolution: "okapibm25@npm:1.4.1"

From 70e05707ca616013f7702aa740d90a52a9d2daf2 Mon Sep 17 00:00:00 2001
From: jacoblee93 <jacoblee93@gmail.com>
Date: Tue, 10 Sep 2024 14:42:58 -0700
Subject: [PATCH 07/11] Remove direct dep

---
 libs/langchain-community/package.json | 1 -
 1 file changed, 1 deletion(-)

diff --git a/libs/langchain-community/package.json b/libs/langchain-community/package.json
index b2cf4e39cea9..7a297de6564f 100644
--- a/libs/langchain-community/package.json
+++ b/libs/langchain-community/package.json
@@ -43,7 +43,6 @@
     "js-yaml": "^4.1.0",
     "langchain": "~0.2.3",
     "langsmith": "~0.1.30",
-    "okapibm25": "^1.4.0",
     "uuid": "^10.0.0",
     "zod": "^3.22.3",
     "zod-to-json-schema": "^3.22.5"

From af5d18fc5c06fe6da5a7ae9a8dabd1f9128dde24 Mon Sep 17 00:00:00 2001
From: jacoblee93 <jacoblee93@gmail.com>
Date: Tue, 10 Sep 2024 14:57:33 -0700
Subject: [PATCH 08/11] Inline dep due to import issues

---
 .../docs/integrations/retrievers/bm25.ipynb   | 101 ++++++++++++++++++
 libs/langchain-community/.gitignore           |   4 +
 libs/langchain-community/package.json         |  13 +++
 .../src/load/import_constants.ts              |   1 +
 .../src/retrievers/bm25.ts                    |  12 +--
 .../src/utils/@furkantoprak/bm25/BM25.ts      | 100 +++++++++++++++++
 .../src/utils/@furkantoprak/bm25/LICENSE.md   |  21 ++++
 7 files changed, 246 insertions(+), 6 deletions(-)
 create mode 100644 docs/core_docs/docs/integrations/retrievers/bm25.ipynb
 create mode 100644 libs/langchain-community/src/utils/@furkantoprak/bm25/BM25.ts
 create mode 100644 libs/langchain-community/src/utils/@furkantoprak/bm25/LICENSE.md

diff --git a/docs/core_docs/docs/integrations/retrievers/bm25.ipynb b/docs/core_docs/docs/integrations/retrievers/bm25.ipynb
new file mode 100644
index 000000000000..b106554c6b40
--- /dev/null
+++ b/docs/core_docs/docs/integrations/retrievers/bm25.ipynb
@@ -0,0 +1,101 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# BM25\n",
+    "\n",
+    "BM25, also known as [Okapi BM25](https://en.wikipedia.org/wiki/Okapi_BM25), is a ranking function used in information retrieval systems to estimate the relevance of documents to a given search query.\n",
+    "\n",
+    "You can use it as part of your retrieval pipeline as a to rerank documents as a postprocessing step after retrieving an initial set of documents from another source.\n",
+    "\n",
+    "## Setup\n",
+    "\n",
+    "The `BM25Retriever` is exported from `@langchain/community`. You'll need to install it like this:\n",
+    "\n",
+    "```{=mdx}\n",
+    "import IntegrationInstallTooltip from \"@mdx_components/integration_install_tooltip.mdx\";\n",
+    "import Npm2Yarn from \"@theme/Npm2Yarn\";\n",
+    "\n",
+    "<IntegrationInstallTooltip></IntegrationInstallTooltip>\n",
+    "\n",
+    "<Npm2Yarn>\n",
+    "  @langchain/community @langchain/core\n",
+    "</Npm2Yarn>\n",
+    "```\n",
+    "\n",
+    "This retriever uses code from [`this implementation`](https://github.com/FurkanToprak/OkapiBM25) of Okapi BM25.\n",
+    "\n",
+    "## Usage\n",
+    "\n",
+    "You can now create a new retriever with previously retrieved documents:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "[\n",
+      "  { pageContent: 'mitochondria is made of lipids', metadata: {} },\n",
+      "  {\n",
+      "    pageContent: 'mitochondria is the powerhouse of the cell',\n",
+      "    metadata: {}\n",
+      "  },\n",
+      "  { pageContent: 'Buildings are made out of brick', metadata: {} },\n",
+      "  { pageContent: 'Buildings are made out of wood', metadata: {} }\n",
+      "]\n"
+     ]
+    }
+   ],
+   "source": [
+    "import { BM25Retriever } from \"@langchain/community/retrievers/bm25\";\n",
+    "\n",
+    "const retriever = BM25Retriever.fromDocuments([\n",
+    "  { pageContent: \"Buildings are made out of brick\", metadata: {} },\n",
+    "  { pageContent: \"Buildings are made out of wood\", metadata: {} },\n",
+    "  { pageContent: \"Buildings are made out of stone\", metadata: {} },\n",
+    "  { pageContent: \"Cars are made out of metal\", metadata: {} },\n",
+    "  { pageContent: \"Cars are made out of plastic\", metadata: {} },\n",
+    "  { pageContent: \"mitochondria is the powerhouse of the cell\", metadata: {} },\n",
+    "  { pageContent: \"mitochondria is made of lipids\", metadata: {} },\n",
+    "], { k: 4 });\n",
+    "\n",
+    "// Will return the 4 documents reranked by the BM25 algorithm\n",
+    "await retriever.invoke(\"mitochondria\");"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "TypeScript",
+   "language": "typescript",
+   "name": "tslab"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "mode": "typescript",
+    "name": "javascript",
+    "typescript": true
+   },
+   "file_extension": ".ts",
+   "mimetype": "text/typescript",
+   "name": "typescript",
+   "version": "3.7.2"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 2
+}
diff --git a/libs/langchain-community/.gitignore b/libs/langchain-community/.gitignore
index 8f6f452a7468..1963c98f29be 100644
--- a/libs/langchain-community/.gitignore
+++ b/libs/langchain-community/.gitignore
@@ -618,6 +618,10 @@ retrievers/amazon_knowledge_base.cjs
 retrievers/amazon_knowledge_base.js
 retrievers/amazon_knowledge_base.d.ts
 retrievers/amazon_knowledge_base.d.cts
+retrievers/bm25.cjs
+retrievers/bm25.js
+retrievers/bm25.d.ts
+retrievers/bm25.d.cts
 retrievers/chaindesk.cjs
 retrievers/chaindesk.js
 retrievers/chaindesk.d.ts
diff --git a/libs/langchain-community/package.json b/libs/langchain-community/package.json
index 7a297de6564f..2ce214216c5b 100644
--- a/libs/langchain-community/package.json
+++ b/libs/langchain-community/package.json
@@ -2100,6 +2100,15 @@
       "import": "./retrievers/amazon_knowledge_base.js",
       "require": "./retrievers/amazon_knowledge_base.cjs"
     },
+    "./retrievers/bm25": {
+      "types": {
+        "import": "./retrievers/bm25.d.ts",
+        "require": "./retrievers/bm25.d.cts",
+        "default": "./retrievers/bm25.d.ts"
+      },
+      "import": "./retrievers/bm25.js",
+      "require": "./retrievers/bm25.cjs"
+    },
     "./retrievers/chaindesk": {
       "types": {
         "import": "./retrievers/chaindesk.d.ts",
@@ -3687,6 +3696,10 @@
     "retrievers/amazon_knowledge_base.js",
     "retrievers/amazon_knowledge_base.d.ts",
     "retrievers/amazon_knowledge_base.d.cts",
+    "retrievers/bm25.cjs",
+    "retrievers/bm25.js",
+    "retrievers/bm25.d.ts",
+    "retrievers/bm25.d.cts",
     "retrievers/chaindesk.cjs",
     "retrievers/chaindesk.js",
     "retrievers/chaindesk.d.ts",
diff --git a/libs/langchain-community/src/load/import_constants.ts b/libs/langchain-community/src/load/import_constants.ts
index 25ef64e5bac1..af2c93648da2 100644
--- a/libs/langchain-community/src/load/import_constants.ts
+++ b/libs/langchain-community/src/load/import_constants.ts
@@ -101,6 +101,7 @@ export const optionalImportEntrypoints: string[] = [
   "langchain_community/callbacks/handlers/upstash_ratelimit",
   "langchain_community/retrievers/amazon_kendra",
   "langchain_community/retrievers/amazon_knowledge_base",
+  "langchain_community/retrievers/bm25",
   "langchain_community/retrievers/dria",
   "langchain_community/retrievers/metal",
   "langchain_community/retrievers/supabase",
diff --git a/libs/langchain-community/src/retrievers/bm25.ts b/libs/langchain-community/src/retrievers/bm25.ts
index 48d1562f27cf..a9de3d9df3f9 100644
--- a/libs/langchain-community/src/retrievers/bm25.ts
+++ b/libs/langchain-community/src/retrievers/bm25.ts
@@ -1,11 +1,12 @@
-import BM25 from "okapibm25";
-import { BaseRetriever } from "@langchain/core/retrievers";
+import { BaseRetriever, BaseRetrieverInput } from "@langchain/core/retrievers";
 import { Document } from "@langchain/core/documents";
 
+import { BM25 } from "../utils/@furkantoprak/bm25/BM25.js";
+
 export type BM25RetrieverOptions = {
   docs: Document[];
   k: number;
-};
+} & BaseRetrieverInput;
 
 /**
  * A retriever that uses the BM25 algorithm to rank documents based on their
@@ -31,7 +32,7 @@ export class BM25Retriever extends BaseRetriever {
   k: number;
 
   constructor(options: BM25RetrieverOptions) {
-    super();
+    super(options);
     this.docs = options.docs;
     this.k = options.k;
   }
@@ -43,8 +44,7 @@ export class BM25Retriever extends BaseRetriever {
   async _getRelevantDocuments(query: string) {
     const processedQuery = this.preprocessFunc(query);
     const documents = this.docs.map((doc) => doc.pageContent);
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    const scores = (BM25 as any).default(documents, processedQuery) as number[];
+    const scores = BM25(documents, processedQuery) as number[];
 
     const scoredDocs = this.docs.map((doc, index) => ({
       document: doc,
diff --git a/libs/langchain-community/src/utils/@furkantoprak/bm25/BM25.ts b/libs/langchain-community/src/utils/@furkantoprak/bm25/BM25.ts
new file mode 100644
index 000000000000..e3e2621168e7
--- /dev/null
+++ b/libs/langchain-community/src/utils/@furkantoprak/bm25/BM25.ts
@@ -0,0 +1,100 @@
+/**
+ * Adapted from
+ * https://github.com/FurkanToprak/OkapiBM25
+ *
+ * Inlined due to CJS import issues.
+ */
+
+/** Gets word count. */
+export const getWordCount = (corpus: string) => {
+  return ((corpus || "").match(/\w+/g) || []).length;
+};
+
+/** Number of occurences of a word in a string. */
+export const getTermFrequency = (term: string, corpus: string) => {
+  return ((corpus || "").match(new RegExp(term, "g")) || []).length;
+};
+
+/** Inverse document frequency. */
+export const getIDF = (term: string, documents: string[]) => {
+  // Number of relevant documents.
+  const relevantDocuments = documents.filter((document: string) =>
+    document.includes(term)
+  ).length;
+  return Math.log(
+    (documents.length - relevantDocuments + 0.5) / (relevantDocuments + 0.5) + 1
+  );
+};
+
+/** Represents a document; useful when sorting results.
+ */
+export interface BMDocument {
+  /** The document is originally scoreed. */
+  document: string;
+  /** The score that the document recieves. */
+  score: number;
+}
+
+/** Constants that are free parameters used in BM25, specifically when generating inverse document frequency. */
+export interface BMConstants {
+  /** Free parameter. Is 0.75 by default.  */
+  b?: number;
+  /** Free parameter. Is 1.2 by default. Generally in range [1.2, 2.0] */
+  k1?: number;
+}
+
+/** If returns positive, the sorting results in secondEl coming before firstEl, else, firstEl comes before secondEL  */
+export type BMSorter = (firstEl: BMDocument, secondEl: BMDocument) => number;
+
+/** Implementation of Okapi BM25 algorithm.
+ *  @param documents: Collection of documents.
+ *  @param keywords: query terms.
+ *  @param constants: Contains free parameters k1 and b. b=0.75 and k1=1.2 by default.
+ *  @param sort: A function that allows you to sort queries by a given rule. If not provided, returns results corresponding to the original order.
+ * If this option is provided, the return type will not be an array of scores but an array of documents with their scores.
+ */
+export function BM25(
+  documents: string[],
+  keywords: string[],
+  constants?: BMConstants,
+  sorter?: BMSorter
+): number[] | BMDocument[] {
+  const b = constants && constants.b ? constants.b : 0.75;
+  const k1 = constants && constants.k1 ? constants.k1 : 1.2;
+  const documentLengths = documents.map((document: string) =>
+    getWordCount(document)
+  );
+  const averageDocumentLength =
+    documentLengths.reduce((a, b) => a + b, 0) / documents.length;
+  const idfByKeyword = keywords.reduce((obj, keyword) => {
+    obj.set(keyword, getIDF(keyword, documents));
+    return obj;
+  }, new Map<string, number>());
+
+  const scores = documents.map((document: string, index: number) => {
+    const score = keywords
+      .map((keyword: string) => {
+        const inverseDocumentFrequency = idfByKeyword.get(keyword);
+        if (inverseDocumentFrequency === undefined) {
+          throw new Error("Missing keyword.");
+        }
+        const termFrequency = getTermFrequency(keyword, document);
+        const documentLength = documentLengths[index];
+        return (
+          (inverseDocumentFrequency * (termFrequency * (k1 + 1))) /
+          (termFrequency +
+            k1 * (1 - b + (b * documentLength) / averageDocumentLength))
+        );
+      })
+      .reduce((a: number, b: number) => a + b, 0);
+    if (sorter) {
+      return { score, document } as BMDocument;
+    }
+    return score;
+  });
+  // sort the results
+  if (sorter) {
+    return (scores as BMDocument[]).sort(sorter);
+  }
+  return scores as number[];
+}
diff --git a/libs/langchain-community/src/utils/@furkantoprak/bm25/LICENSE.md b/libs/langchain-community/src/utils/@furkantoprak/bm25/LICENSE.md
new file mode 100644
index 000000000000..8dd59105dd36
--- /dev/null
+++ b/libs/langchain-community/src/utils/@furkantoprak/bm25/LICENSE.md
@@ -0,0 +1,21 @@
+# MIT License
+
+## Copyright (c) 2020 Furkan Toprak
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

From 5811ca680dbcfa20ce745ba194061ab59982c888 Mon Sep 17 00:00:00 2001
From: jacoblee93 <jacoblee93@gmail.com>
Date: Tue, 10 Sep 2024 15:04:04 -0700
Subject: [PATCH 09/11] Fix

---
 libs/langchain-community/src/retrievers/bm25.ts | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/libs/langchain-community/src/retrievers/bm25.ts b/libs/langchain-community/src/retrievers/bm25.ts
index a9de3d9df3f9..dfc04709cba1 100644
--- a/libs/langchain-community/src/retrievers/bm25.ts
+++ b/libs/langchain-community/src/retrievers/bm25.ts
@@ -55,8 +55,4 @@ export class BM25Retriever extends BaseRetriever {
 
     return scoredDocs.slice(0, this.k).map((item) => item.document);
   }
-
-  async invoke(input: string): Promise<Document[]> {
-    return this._getRelevantDocuments(input);
-  }
 }

From 1deb7b1d9f98f16cb14460e75b2f29b3efc95b2d Mon Sep 17 00:00:00 2001
From: jacoblee93 <jacoblee93@gmail.com>
Date: Tue, 10 Sep 2024 15:08:05 -0700
Subject: [PATCH 10/11] Remove dep

---
 libs/langchain-community/langchain.config.js          | 1 -
 libs/langchain-community/package.json                 | 5 -----
 libs/langchain-community/src/load/import_constants.ts | 1 -
 libs/langchain-community/src/load/import_map.ts       | 1 +
 4 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/libs/langchain-community/langchain.config.js b/libs/langchain-community/langchain.config.js
index 85ab7194bfb6..ea6b48d2e3a7 100644
--- a/libs/langchain-community/langchain.config.js
+++ b/libs/langchain-community/langchain.config.js
@@ -427,7 +427,6 @@ export const config = {
     "chat_models/zhipuai",
     "retrievers/amazon_kendra",
     "retrievers/amazon_knowledge_base",
-    "retrievers/bm25",
     "retrievers/dria",
     "retrievers/metal",
     "retrievers/supabase",
diff --git a/libs/langchain-community/package.json b/libs/langchain-community/package.json
index 2ce214216c5b..78ff8a877b6a 100644
--- a/libs/langchain-community/package.json
+++ b/libs/langchain-community/package.json
@@ -186,7 +186,6 @@
     "node-llama-cpp": "2.7.3",
     "notion-to-md": "^3.1.0",
     "officeparser": "^4.0.4",
-    "okapibm25": "^1.4.1",
     "pdf-parse": "1.1.1",
     "pg": "^8.11.0",
     "pg-copy-streams": "^6.0.5",
@@ -313,7 +312,6 @@
     "node-llama-cpp": "*",
     "notion-to-md": "^3.1.0",
     "officeparser": "^4.0.4",
-    "okapibm25": "^1.4.1",
     "pdf-parse": "1.1.1",
     "pg": "^8.11.0",
     "pg-copy-streams": "^6.0.5",
@@ -634,9 +632,6 @@
     "officeparser": {
       "optional": true
     },
-    "okapibm25": {
-      "optional": true
-    },
     "pdf-parse": {
       "optional": true
     },
diff --git a/libs/langchain-community/src/load/import_constants.ts b/libs/langchain-community/src/load/import_constants.ts
index af2c93648da2..25ef64e5bac1 100644
--- a/libs/langchain-community/src/load/import_constants.ts
+++ b/libs/langchain-community/src/load/import_constants.ts
@@ -101,7 +101,6 @@ export const optionalImportEntrypoints: string[] = [
   "langchain_community/callbacks/handlers/upstash_ratelimit",
   "langchain_community/retrievers/amazon_kendra",
   "langchain_community/retrievers/amazon_knowledge_base",
-  "langchain_community/retrievers/bm25",
   "langchain_community/retrievers/dria",
   "langchain_community/retrievers/metal",
   "langchain_community/retrievers/supabase",
diff --git a/libs/langchain-community/src/load/import_map.ts b/libs/langchain-community/src/load/import_map.ts
index 59efd56b760e..5bbd9e4d0a01 100644
--- a/libs/langchain-community/src/load/import_map.ts
+++ b/libs/langchain-community/src/load/import_map.ts
@@ -54,6 +54,7 @@ export * as chat_models__moonshot from "../chat_models/moonshot.js";
 export * as chat_models__ollama from "../chat_models/ollama.js";
 export * as chat_models__togetherai from "../chat_models/togetherai.js";
 export * as chat_models__yandex from "../chat_models/yandex.js";
+export * as retrievers__bm25 from "../retrievers/bm25.js";
 export * as retrievers__chaindesk from "../retrievers/chaindesk.js";
 export * as retrievers__databerry from "../retrievers/databerry.js";
 export * as retrievers__remote from "../retrievers/remote/index.js";

From fd77a98ccf448dc8f64ec88272fe2b09a24fe93f Mon Sep 17 00:00:00 2001
From: jacoblee93 <jacoblee93@gmail.com>
Date: Tue, 10 Sep 2024 15:10:17 -0700
Subject: [PATCH 11/11] Update lock

---
 yarn.lock | 11 -----------
 1 file changed, 11 deletions(-)

diff --git a/yarn.lock b/yarn.lock
index 721962918d0a..ff5f4ee61df5 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -11320,7 +11320,6 @@ __metadata:
     node-llama-cpp: 2.7.3
     notion-to-md: ^3.1.0
     officeparser: ^4.0.4
-    okapibm25: ^1.4.1
     pdf-parse: 1.1.1
     pg: ^8.11.0
     pg-copy-streams: ^6.0.5
@@ -11449,7 +11448,6 @@ __metadata:
     node-llama-cpp: "*"
     notion-to-md: ^3.1.0
     officeparser: ^4.0.4
-    okapibm25: ^1.4.1
     pdf-parse: 1.1.1
     pg: ^8.11.0
     pg-copy-streams: ^6.0.5
@@ -11670,8 +11668,6 @@ __metadata:
       optional: true
     officeparser:
       optional: true
-    okapibm25:
-      optional: true
     pdf-parse:
       optional: true
     pg:
@@ -35050,13 +35046,6 @@ __metadata:
   languageName: node
   linkType: hard
 
-"okapibm25@npm:^1.4.1":
-  version: 1.4.1
-  resolution: "okapibm25@npm:1.4.1"
-  checksum: f619b8888fa983861116f2fd4f2896411d157a75c5ae79d81fd9322821d274f127e0199e0f0b93961c49b6f31b710723ffd893a77820bdd0e52c859c2cbcb594
-  languageName: node
-  linkType: hard
-
 "ollama@npm:^0.5.6":
   version: 0.5.6
   resolution: "ollama@npm:0.5.6"