Storage: Support the s3, azure blob as the object storage of ragflow. (#2278)

### What problem does this PR solve?

issue: https://github.com/infiniflow/ragflow/issues/2277

_Briefly describe what this PR aims to solve. Include background context
that will help reviewers understand the purpose of the PR._

### Type of change

- [ ] Bug Fix (non-breaking change which fixes an issue)
- [x] New Feature (non-breaking change which adds functionality)
- [ ] Documentation Update
- [ ] Refactoring
- [ ] Performance Improvement
- [ ] Other (please describe):

Co-authored-by: Kevin Hu <kevinhu.sh@gmail.com>

api/apps/api_app.py

@@ -39,7 +39,7 @@ from itsdangerous import URLSafeTimedSerializer
 
 from api.utils.file_utils import filename_type, thumbnail
 from rag.nlp import keyword_extraction
-from rag.utils.minio_conn import MINIO
+from rag.utils.storage_factory import STORAGE_IMPL
 
 from api.db.services.canvas_service import CanvasTemplateService, UserCanvasService
 from agent.canvas import Canvas
@@ -427,10 +427,10 @@ def upload():
                 retmsg="This type of file has not been supported yet!")
 
         location = filename
-        while MINIO.obj_exist(kb_id, location):
+        while STORAGE_IMPL.obj_exist(kb_id, location):
             location += "_"
         blob = request.files['file'].read()
-        MINIO.put(kb_id, location, blob)
+        STORAGE_IMPL.put(kb_id, location, blob)
         doc = {
             "id": get_uuid(),
             "kb_id": kb.id,
@@ -650,7 +650,7 @@ def document_rm():
             FileService.filter_delete([File.source_type == FileSource.KNOWLEDGEBASE, File.id == f2d[0].file_id])
             File2DocumentService.delete_by_document_id(doc_id)
 
-            MINIO.rm(b, n)
+            STORAGE_IMPL.rm(b, n)
         except Exception as e:
             errors += str(e)
 
@@ -723,7 +723,7 @@ def completion_faq():
             if ans["reference"]["chunks"][chunk_idx]["img_id"]:
                 try:
                     bkt, nm = ans["reference"]["chunks"][chunk_idx]["img_id"].split("-")
-                    response = MINIO.get(bkt, nm)
+                    response = STORAGE_IMPL.get(bkt, nm)
                     data_type_picture["url"] = base64.b64encode(response).decode('utf-8')
                     data.append(data_type_picture)
                     break