infra: related section in docs (#24829)

Co-authored-by: Erick Friis <erick@langchain.dev>

docs/Makefile

@@ -69,10 +69,13 @@ render:
 md-sync:
 	rsync -avm --include="*/" --include="*.mdx" --include="*.md" --include="*.png" --include="*/_category_.yml" --exclude="*" $(INTERMEDIATE_DIR)/ $(OUTPUT_NEW_DOCS_DIR)
 
+append-related:
+	$(PYTHON) scripts/append_related_links.py $(OUTPUT_NEW_DOCS_DIR)
+
 generate-references:
 	$(PYTHON) scripts/generate_api_reference_links.py --docs_dir $(OUTPUT_NEW_DOCS_DIR)
 
-build: install-py-deps generate-files copy-infra render md-sync
+build: install-py-deps generate-files copy-infra render md-sync append-related
 
 vercel-build: install-vercel-deps build generate-references
 	rm -rf docs

docs/scripts/append_related_links.py

@@ -0,0 +1,74 @@
+import itertools
+import multiprocessing
+import re
+import sys
+from pathlib import Path
+
+
+def _generate_related_links_section(integration_type: str, notebook_name: str):
+    concept_display_name = None
+    concept_heading = None
+    if integration_type == "chat":
+        concept_display_name = "Chat model"
+        concept_heading = "chat-models"
+    elif integration_type == "llms":
+        concept_display_name = "LLM"
+        concept_heading = "llms"
+    elif integration_type == "text_embedding":
+        concept_display_name = "Embedding model"
+        concept_heading = "embedding-models"
+    elif integration_type == "document_loaders":
+        concept_display_name = "Document loader"
+        concept_heading = "document-loaders"
+    elif integration_type == "vectorstores":
+        concept_display_name = "Vector store"
+        concept_heading = "vector-stores"
+    elif integration_type == "retrievers":
+        concept_display_name = "Retriever"
+        concept_heading = "retrievers"
+    elif integration_type == "tools":
+        concept_display_name = "Tool"
+        concept_heading = "tools"
+    elif integration_type == "stores":
+        concept_display_name = "Key-value store"
+        concept_heading = "key-value-stores"
+        # Special case because there are no key-value store how-tos yet
+        return f"""## Related
+
+- [{concept_display_name} conceptual guide](/docs/concepts/#{concept_heading})
+"""
+    else:
+        return None
+    return f"""## Related
+
+- {concept_display_name} [conceptual guide](/docs/concepts/#{concept_heading})
+- {concept_display_name} [how-to guides](/docs/how_to/#{concept_heading})
+"""
+
+
+def _process_path(doc_path: Path):
+    content = doc_path.read_text()
+    print(doc_path)
+    pattern = r"/docs/integrations/([^/]+)/([^/]+).mdx?"
+    match = re.search(pattern, str(doc_path))
+    print(bool(match))
+    if match and match.group(2) != "index":
+        integration_type = match.group(1)
+        notebook_name = match.group(2)
+        related_links_section = _generate_related_links_section(
+            integration_type, notebook_name
+        )
+        if related_links_section:
+            content = content + "\n\n" + related_links_section
+            doc_path.write_text(content)
+
+
+if __name__ == "__main__":
+    output_docs_dir = Path(sys.argv[1])
+
+    mds = output_docs_dir.rglob("integrations/**/*.md")
+    mdxs = output_docs_dir.rglob("integrations/**/*.mdx")
+    paths = itertools.chain(mds, mdxs)
+    # modify all md files in place
+    with multiprocessing.Pool() as pool:
+        pool.map(_process_path, paths)