API: completed delete_doc api (#1290)

### What problem does this PR solve?

Adds the functionality of deleting documentation

### Type of change

- [x] New Feature (non-breaking change which adds functionality)

sdk/python/test/test_document.py

@@ -149,12 +149,96 @@ class TestFile(TestSdk):
         res = ragflow.upload_local_file(dataset_id, file_paths)
         assert res['code'] == RetCode.ARGUMENT_ERROR and res['message'] == 'Remote files have not unsupported.'
 
-# ----------------------------upload remote files-----------------------------------------------------
+# ----------------------------delete a file-----------------------------------------------------
+    def test_delete_one_file(self):
+        """
+        Test deleting one file with success.
+        """
+        ragflow = RAGFlow(API_KEY, HOST_ADDRESS)
+        created_res = ragflow.create_dataset("test_delete_one_file")
+        dataset_id = created_res['data']['dataset_id']
+        file_paths = ["test_data/test.txt"]
+        res = ragflow.upload_local_file(dataset_id, file_paths)
+        # get the doc_id
+        data = res['data'][0]
+        doc_id = data['id']
+        # delete the files
+        deleted_res = ragflow.delete_files(doc_id, dataset_id)
+        # assert value
+        assert deleted_res['code'] == RetCode.SUCCESS and deleted_res['data'] is True
+
+    def test_delete_document_with_not_existing_document(self):
+        """
+        Test deleting a document that does not exist with failure.
+        """
+        ragflow = RAGFlow(API_KEY, HOST_ADDRESS)
+        created_res = ragflow.create_dataset("test_delete_document_with_not_existing_document")
+        dataset_id = created_res['data']['dataset_id']
+        res = ragflow.delete_files("111", dataset_id)
+        assert res['code'] == RetCode.DATA_ERROR and res['message'] == 'Document 111 not found!'
+
+    def test_delete_document_with_creating_100_documents_and_deleting_100_documents(self):
+        """
+        Test deleting documents when uploading 100 docs and deleting 100 docs.
+        """
+        # upload 100 docs
+        ragflow = RAGFlow(API_KEY, HOST_ADDRESS)
+        created_res = ragflow.create_dataset("test_delete_one_file")
+        dataset_id = created_res['data']['dataset_id']
+        file_paths = ["test_data/test.txt"] * 100
+        res = ragflow.upload_local_file(dataset_id, file_paths)
+
+        # get the doc_id
+        data = res['data']
+        for d in data:
+            doc_id = d['id']
+            # delete the files
+            deleted_res = ragflow.delete_files(doc_id, dataset_id)
+            # assert value
+            assert deleted_res['code'] == RetCode.SUCCESS and deleted_res['data'] is True
+
+    def test_delete_document_from_nonexistent_dataset(self):
+        """
+        Test deleting documents from a non-existent dataset
+        """
+        ragflow = RAGFlow(API_KEY, HOST_ADDRESS)
+        created_res = ragflow.create_dataset("test_delete_one_file")
+        dataset_id = created_res['data']['dataset_id']
+        file_paths = ["test_data/test.txt"]
+        res = ragflow.upload_local_file(dataset_id, file_paths)
+        # get the doc_id
+        data = res['data'][0]
+        doc_id = data['id']
+        # delete the files
+        deleted_res = ragflow.delete_files(doc_id, "000")
+        # assert value
+        assert (deleted_res['code'] == RetCode.ARGUMENT_ERROR and deleted_res['message'] ==
+                f'The document {doc_id} is not in the dataset: 000, but in the dataset: {dataset_id}.')
+
+    def test_delete_document_which_is_located_in_other_dataset(self):
+        """
+        Test deleting a document which is located in other dataset.
+        """
+        ragflow = RAGFlow(API_KEY, HOST_ADDRESS)
+        # upload a document
+        created_res = ragflow.create_dataset("test_delete_document_which_is_located_in_other_dataset")
+        created_res_id = created_res['data']['dataset_id']
+        file_paths = ["test_data/test.txt"]
+        res = ragflow.upload_local_file(created_res_id, file_paths)
+        # other dataset
+        other_res = ragflow.create_dataset("other_dataset")
+        other_dataset_id = other_res['data']['dataset_id']
+        # get the doc_id
+        data = res['data'][0]
+        doc_id = data['id']
+        # delete the files from the other dataset
+        deleted_res = ragflow.delete_files(doc_id, other_dataset_id)
+        # assert value
+        assert (deleted_res['code'] == RetCode.ARGUMENT_ERROR and deleted_res['message'] ==
+                f'The document {doc_id} is not in the dataset: {other_dataset_id}, but in the dataset: {created_res_id}.')
 
 # ----------------------------download a file-----------------------------------------------------
 
-# ----------------------------delete a file-----------------------------------------------------
-
 # ----------------------------enable rename-----------------------------------------------------
 
 # ----------------------------list files-----------------------------------------------------