RAGFlow go API server (#13240)

# RAGFlow Go Implementation Plan 🚀

This repository tracks the progress of porting RAGFlow to Go. We'll
implement core features and provide performance comparisons between
Python and Go versions.

## Implementation Checklist

- [x] User Management APIs
- [x] Dataset Management Operations
- [x] Retrieval Test
- [x] Chat Management Operations
- [x] Infinity Go SDK

---------

Signed-off-by: Jin Hai <haijin.chn@gmail.com>
Co-authored-by: Yingfeng Zhang <yingfeng.zhang@gmail.com>

internal/model/file.go

@@ -0,0 +1,49 @@
+//
+//  Copyright 2026 The InfiniFlow Authors. All Rights Reserved.
+//
+//  Licensed under the Apache License, Version 2.0 (the "License");
+//  you may not use this file except in compliance with the License.
+//  You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+//  Unless required by applicable law or agreed to in writing, software
+//  distributed under the License is distributed on an "AS IS" BASIS,
+//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+//  See the License for the specific language governing permissions and
+//  limitations under the License.
+//
+
+package model
+
+// File file model
+type File struct {
+	ID         string  `gorm:"column:id;primaryKey;size:32" json:"id"`
+	ParentID   string  `gorm:"column:parent_id;size:32;not null;index" json:"parent_id"`
+	TenantID   string  `gorm:"column:tenant_id;size:32;not null;index" json:"tenant_id"`
+	CreatedBy  string  `gorm:"column:created_by;size:32;not null;index" json:"created_by"`
+	Name       string  `gorm:"column:name;size:255;not null;index" json:"name"`
+	Location   *string `gorm:"column:location;size:255;index" json:"location,omitempty"`
+	Size       int64   `gorm:"column:size;default:0;index" json:"size"`
+	Type       string  `gorm:"column:type;size:32;not null;index" json:"type"`
+	SourceType string  `gorm:"column:source_type;size:128;not null;default:'';index" json:"source_type"`
+	BaseModel
+}
+
+// TableName specify table name
+func (File) TableName() string {
+	return "file"
+}
+
+// File2Document file to document mapping model
+type File2Document struct {
+	ID         string  `gorm:"column:id;primaryKey;size:32" json:"id"`
+	FileID     *string `gorm:"column:file_id;size:32;index" json:"file_id,omitempty"`
+	DocumentID *string `gorm:"column:document_id;size:32;index" json:"document_id,omitempty"`
+	BaseModel
+}
+
+// TableName specify table name
+func (File2Document) TableName() string {
+	return "file2document"
+}