后端：新增 /api/upload，完善异常处理与中文文案；本地验证通过。

app.py

@@ -2,37 +2,11 @@ from flask import Flask, render_template, request, jsonify, send_from_directory
 import numpy as np
 from scipy import stats
 import os
+import json
+from werkzeug.exceptions import RequestEntityTooLarge
 
 app = Flask(__name__)
-# Security: Limit max upload size to 5MB
-app.config['MAX_CONTENT_LENGTH'] = 5 * 1024 * 1024 
-
-# Global Error Handlers
-@app.errorhandler(413)
-def request_entity_too_large(error):
-    return jsonify({"error": "File too large (Max 5MB)"}), 413
-
-@app.errorhandler(500)
-def internal_error(error):
-    return jsonify({"error": "Internal Server Error"}), 500
-
-@app.errorhandler(404)
-def not_found(error):
-    return jsonify({"error": "Not Found"}), 404
-
-def validate_file(file_stream):
-    """
-    Robust file validation:
-    1. Check for null bytes (binary file protection)
-    2. Check file content validity (basic JSON structure)
-    """
-    chunk = file_stream.read(1024)
-    file_stream.seek(0) # Reset pointer
-    
-    if b'\0' in chunk:
-        return False, "File contains binary data (null bytes)"
-    
-    return True, ""
+app.config['MAX_CONTENT_LENGTH'] = 6 * 1024 * 1024
 
 @app.route('/')
 def index():
@@ -42,60 +16,19 @@ def index():
 def health():
     return "OK", 200
 
-@app.route('/api/upload', methods=['POST'])
-def upload_data():
-    """
-    Handle history data upload.
-    Expects a JSON file with 'history' array.
-    """
-    if 'file' not in request.files:
-        return jsonify({"error": "No file part"}), 400
-        
-    file = request.files['file']
-    if file.filename == '':
-        return jsonify({"error": "No selected file"}), 400
-        
-    if not file.filename.lower().endswith('.json'):
-        return jsonify({"error": "Only JSON files are allowed"}), 400
-
-    # Binary check
-    is_valid, error_msg = validate_file(file.stream)
-    if not is_valid:
-        return jsonify({"error": error_msg}), 400
-
-    try:
-        import json
-        data = json.load(file)
-        if 'history' not in data or not isinstance(data['history'], list):
-             return jsonify({"error": "Invalid JSON format: must contain 'history' list"}), 400
-             
-        # Validate history items
-        valid_history = []
-        for item in data['history']:
-            if 'price' in item and 'sales' in item:
-                valid_history.append(item)
-                
-        return jsonify({
-            "status": "success", 
-            "message": f"Successfully loaded {len(valid_history)} records",
-            "history": valid_history
-        })
-    except Exception as e:
-        return jsonify({"error": f"Failed to parse JSON: {str(e)}"}), 500
-
 @app.route('/api/optimize', methods=['POST'])
 def optimize():
     """
-    Analyzes sales data to estimate demand curve and recommend optimal price.
-    Input: JSON { "history": [ {"price": 10, "sales": 50}, ... ], "mc": 5 }
-    Output: JSON { "elasticity": -1.5, "optimal_price": 12.5, "model": "linear" }
+    基于历史价格-销量数据估计线性需求曲线并推荐最优价格。
+    输入: JSON { "history": [ {"price": 10, "sales": 50}, ... ], "mc": 5 }
+    输出: JSON { "elasticity": -1.5, "optimal_price": 12.5 }
     """
     data = request.json
     history = data.get('history', [])
     marginal_cost = data.get('mc', 0)
     
     if len(history) < 3:
-        return jsonify({"error": "Need at least 3 data points"}), 400
+        return jsonify({"error": "至少需要 3 条数据点"}), 400
 
     prices = np.array([h['price'] for h in history])
     sales = np.array([h['sales'] for h in history])
@@ -105,12 +38,11 @@ def optimize():
     slope, intercept, r_value, p_value, std_err = stats.linregress(prices, sales)
 
     if slope >= 0:
-        # Abnormal demand (higher price -> higher sales?), fallback
         return jsonify({
             "status": "warning",
-            "message": "Demand curve is inverted or flat (Slope >= 0). Cannot optimize.",
+            "message": "需求曲线异常或过于平坦（斜率≥0），无法优化，建议保持当前价格。",
             "slope": slope,
-            "optimal_price": prices[-1] # Keep current
+            "optimal_price": prices[-1]
         })
 
     # Profit = (P - MC) * Q = (P - MC) * (a + bP)
@@ -136,8 +68,95 @@ def optimize():
         "r_squared": r_value**2,
         "optimal_price": round(optimal_price, 2),
         "elasticity": round(elasticity, 2),
-        "message": "Optimization successful based on linear demand model."
+        "message": "线性需求模型优化成功，已生成建议价格。"
     })
 
+@app.route('/api/upload', methods=['POST'])
+def upload():
+    """
+    上传并解析历史数据 JSON 文件，返回标准化的 history。
+    支持两种格式：
+      1) { "history": [ {price, sales, ...}, ... ] }
+      2) [ {price, sales, ...}, ... ]
+    约束：文件大小 ≤ 5MB，必须为 UTF-8 文本 JSON。
+    """
+    if 'file' not in request.files:
+        return jsonify({"error": "未找到文件字段"}), 400
+    file = request.files['file']
+    filename = (file.filename or '').lower()
+    if not filename.endswith('.json'):
+        return jsonify({"error": "只支持 JSON 文件"}), 400
+
+    # 读取并校验大小
+    file.seek(0, os.SEEK_END)
+    size = file.tell()
+    file.seek(0)
+    if size > 5 * 1024 * 1024:
+        return jsonify({"error": "文件大小不能超过 5MB"}), 400
+
+    try:
+        raw = file.read()
+        try:
+            text = raw.decode('utf-8')
+        except UnicodeDecodeError:
+            return jsonify({"error": "文件内容不是有效的 UTF-8 文本"}), 400
+
+        payload = json.loads(text)
+        if isinstance(payload, dict) and 'history' in payload:
+            incoming = payload['history']
+        elif isinstance(payload, list):
+            incoming = payload
+        else:
+            return jsonify({"error": "JSON 格式不正确，应为 {history: [...]} 或数组"}), 400
+
+        cleaned = []
+        day_counter = 0
+        for item in incoming:
+            try:
+                price = float(item.get('price'))
+                sales = int(item.get('sales'))
+            except Exception:
+                # 跳过不可解析的数据行
+                continue
+            if price <= 0 or sales < 0:
+                continue
+            day_counter += 1
+            revenue = item.get('revenue')
+            if revenue is None:
+                revenue = price * sales
+            competitor_price = item.get('competitorPrice', 50)
+            cleaned.append({
+                "day": item.get('day', day_counter),
+                "price": price,
+                "sales": sales,
+                "revenue": revenue,
+                "competitorPrice": competitor_price
+            })
+
+        if not cleaned:
+            return jsonify({"error": "数据为空或格式不正确"}), 400
+
+        return jsonify({"history": cleaned})
+    except json.JSONDecodeError:
+        return jsonify({"error": "JSON 解析失败，请检查文件内容"}), 400
+    except Exception as e:
+        return jsonify({"error": f"服务器解析失败: {str(e)}"}), 500
+
+@app.errorhandler(404)
+def handle_404(e):
+    if request.path.startswith('/api/'):
+        return jsonify({"error": "未找到接口", "path": request.path}), 404
+    return render_template('index.html'), 404
+
+@app.errorhandler(500)
+def handle_500(e):
+    if request.path.startswith('/api/'):
+        return jsonify({"error": "服务器内部错误"}), 500
+    return render_template('index.html'), 500
+
+@app.errorhandler(RequestEntityTooLarge)
+def handle_file_too_large(e):
+    return jsonify({"error": "文件过大，服务端限制为 6MB"}), 413
+
 if __name__ == '__main__':
     app.run(host='0.0.0.0', port=7860, debug=True)

requirements.txt

@@ -1,4 +1,5 @@
 Flask
 numpy
 scipy
+pandas
 gunicorn