python - 如何在 Apache Thrift 中编写列表？

Question

我需要你的帮助。我想在一个简单的任务上测试 Apache Thrift。我在 MySQL 数据库中有几个表，我想将存储的数据保存到一个文件中。

因此，我创建了一个 Thrift IDL 文件，如下所示:

exception InvalidOperation {
    1: i32 what,
    2: string why,
}

struct Product{
    1: i32     id
    2: i16     resource_id,
    3: i16     resource_amount,
    4: double  price,
    5: string  comment,
    6: string  comment_text_color,
    7: string  comment_bgr_color,
    8: string  image_file_id,
    9: i16     active,
    10: string title,
    11: string description,
    12: i16    item_index,
    13: i16    is_special,
    14: string banner_file_id
}

struct File{
    1: string  id
    2: string  path,
    3: string  checksum,
    4: string  size,
}

struct StaticData{
    1: list<Product> Products = [];
    2: list<File> Files = [];
}

service DataLibrary {
     void ping(),
}

并写了一些简单的python代码:服务器.py:

# -*- coding: utf-8 -*-

import thriftpy

from thriftpy.rpc import make_server

tutorial_thrift = thriftpy.load("tutorial.thrift",
                                module_name="tutorial_thrift")

class StaticDataHandler(object):
    def __init__(self):
        self.log = {}

    def ping(self):
        print('ping()')

def main():
    server = make_server(tutorial_thrift.StaticData, StaticDataHandler(),
                         '127.0.0.1', 6000)
    print("serving...")
    server.serve()

if __name__ == '__main__':
    main()

客户端.py:

# -*- coding: utf-8 -*-
import sys
import thriftpy

sys.path.append("gen-py")
from thriftpy.rpc import client_context
from thrift.transport import TTransport
from thrift.protocol import TBinaryProtocol
from thrift import Thrift
from tutorial import ttypes

tutorial_thrift = thriftpy.load("tutorial.thrift",
                                module_name="tutorial_thrift")


def get_products_from_db():
    product_list = []

    for i in range(1, 500):
        product_list.append({'id': i,
                             'resource_id': i,
                             'resource_amount': i,
                             'price': i,
                             'comment': 'comment' + str(i),
                             'comment_text_color': 'yellow',
                             'comment_bgr_color': 'blue',
                             'image_file_id': 'file_' + str(i),
                             'active': 1,
                             'title': 'title_' + str(i),
                             'description': 'description' + str(i),
                             'item_index': i,
                             'is_special': 1,
                             'banner_file_id': 'banner_' + str(i)})
    return product_list


def main():
    with client_context(tutorial_thrift.DataLibrary,
                        '127.0.0.1', 6000) as client:
        client.ping()
        print("ping()")
        product_list = get_products_from_db()
        static_data = tutorial_thrift.StaticData()
        static_data.Products.append(product_list)
        static_data_save_to_file(static_data)


def static_data_save_to_file(data):
    trans = TTransport.TFileObjectTransport(open("static_data", "wb"))
    proto = TBinaryProtocol.TBinaryProtocol(trans)
    static_data = tutorial_thrift.StaticData()
    proto.writeStructBegin(static_data)
    proto.writeListBegin(Thrift.TType.LIST, len(data.Products))
    print(data.Products)
    # proto.writeContainerList(data.Products, Thrift.TType.LIST)
    proto.writeFieldEnd()
    proto.writeFieldStop()
    proto.writeStructEnd()
    print('Recording finished')


def product_save_to_file():
    trans = TTransport.TFileObjectTransport(open("data", "wb"))
    proto = TBinaryProtocol.TBinaryProtocol(trans)
    product_list = get_products_from_db()
    product = product_list[0]

    print(product)
    print('Starting record data to file')
    proto.writeStructBegin(product)

    proto.writeFieldBegin("id", Thrift.TType.I32, 1)
    proto.writeI32(product.id)
    proto.writeFieldEnd()

    proto.writeFieldBegin("resource_id", Thrift.TType.I16, 2)
    proto.writeI16(product.resource_id)
    proto.writeFieldEnd()

    proto.writeFieldBegin("resource_amount", Thrift.TType.I16, 3)
    proto.writeI16(product.resource_amount)
    proto.writeFieldEnd()

    proto.writeFieldBegin("price", Thrift.TType.DOUBLE, 4)
    proto.writeDouble(product.price)
    proto.writeFieldEnd()

    proto.writeFieldBegin("comment", Thrift.TType.STRING, 5)
    proto.writeString(product.comment)
    proto.writeFieldEnd()

    proto.writeFieldBegin("comment_text_color", Thrift.TType.STRING, 6)
    proto.writeString(product.comment_text_color)
    proto.writeFieldEnd()

    proto.writeFieldBegin("comment_bgr_color", Thrift.TType.STRING, 7)
    proto.writeString(product.comment_bgr_color)
    proto.writeFieldEnd()

    proto.writeFieldBegin("image_file_id", Thrift.TType.STRING, 8)
    proto.writeString(product.image_file_id)
    proto.writeFieldEnd()

    proto.writeFieldBegin("active", Thrift.TType.I16, 9)
    proto.writeI16(product.active)
    proto.writeFieldEnd()

    proto.writeFieldBegin("title", Thrift.TType.STRING, 10)
    proto.writeString(product.title)
    proto.writeFieldEnd()

    proto.writeFieldBegin("description", Thrift.TType.STRING, 11)
    proto.writeString(product.description)
    proto.writeFieldEnd()

    proto.writeFieldBegin("item_index", Thrift.TType.I16, 12)
    proto.writeI16(product.item_index)
    proto.writeFieldEnd()

    proto.writeFieldBegin("is_special", Thrift.TType.I16, 13)
    proto.writeI16(product.is_special)
    proto.writeFieldEnd()

    proto.writeFieldBegin("banner_file_id", Thrift.TType.STRING, 14)
    proto.writeString(product.banner_file_id)
    proto.writeFieldEnd()

    proto.writeFieldStop()
    proto.writeStructEnd()
    print('Recording finished')


def product_read_from_file():
    trans = TTransport.TFileObjectTransport(open("data", "rb"))
    trans.open()
    proto = TBinaryProtocol.TBinaryProtocol(trans)
    ro = ttypes.Product()
    ro.read(proto)
    print('started')
    # Display the contents of the Product
    print("\nReading Product")
    print("-------------------------")
    print("resource_id     : %d" % ro.resource_id)
    print("resource_amount : %s" % ro.resource_amount)
    print("Price           : %f" % ro.price)
    print('end')

if __name__ == '__main__':
    main()

我卡在了这一行的函数 static_data_save_to_file 中:

# proto.writeContainerList(data.Products, Thrift.TType.LIST)

我不明白，我应该向这个方法发送哪些属性，以及如何计算大小。

我尝试只将一个产品保存到文件中并读取它，它可以工作，但现在我需要在一个结构 (StaticData) 中插入几个列表(产品、文件)并将其保存在文件中。

Answer 1

我认为您正在尝试以一种过于复杂的方式进行操作。我没有测试以下内容，但应该这样做:

def static_data_save_to_file(data):
    trans = TTransport.TFileObjectTransport(open("static_data", "wb"))
    proto = TBinaryProtocol.TBinaryProtocol(trans)
    data.write(proto)
    print('Recording finished')