/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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. */ # Thrift Tutorial # Mark Slee (mcslee@facebook.com) # # This file aims to teach you how to use Thrift, in a .thrift file. Neato. The # first thing to notice is that .thrift files support standard shell comments. # This lets you make your thrift file executable and include your Thrift build # step on the top line. And you can place comments like this anywhere you like. # # Before running this file, you will need to have installed the thrift compiler # into /usr/local/bin. /** * The first thing to know about are types. The available types in Thrift are: * * bool Boolean, one byte * byte Signed byte * i16 Signed 16-bit integer * i32 Signed 32-bit integer * i64 Signed 64-bit integer * double 64-bit floating point value * string String * binary Blob (byte array) * map Map from one type to another * list Ordered list of one type * set Set of unique elements of one type * * Did you also notice that Thrift supports C style comments? */ // Just in case you were wondering... yes. We support simple C comments too. /** * Thrift files can reference other Thrift files to include common struct * and service definitions. These are found using the current path, or by * searching relative to any paths specified with the -I compiler flag. * * Included objects are accessed using the name of the .thrift file as a * prefix. i.e. shared.SharedObject */ include "shared.thrift" /** * Thrift files can namespace, package, or prefix their output in various * target languages. */ namespace cpp tutorial namespace d tutorial namespace java tutorial namespace php tutorial namespace perl tutorial namespace haxe tutorial /** * Thrift lets you do typedefs to get pretty names for your types. Standard * C style here. */ typedef i32 MyInteger /** * Thrift also lets you define constants for use across languages. Complex * types and structs are specified using JSON notation. */ const i32 INT32CONSTANT = 9853 const map MAPCONSTANT = {'hello':'world', 'goodnight':'moon'} /** * You can define enums, which are just 32 bit integers. Values are optional * and start at 1 if not supplied, C style again. */ enum Operation { ADD = 1, SUBTRACT = 2, MULTIPLY = 3, DIVIDE = 4 } /** * Structs are the basic complex data structures. They are comprised of fields * which each have an integer identifier, a type, a symbolic name, and an * optional default value. * * Fields can be declared "optional", which ensures they will not be included * in the serialized output if they aren't set. Note that this requires some * manual management in some languages. */ struct Work { 1: i32 num1 = 0, 2: i32 num2, 3: Operation op, 4: optional string comment, } /** * Structs can also be exceptions, if they are nasty. */ exception InvalidOperation { 1: i32 what, 2: string why } /** * Ahh, now onto the cool part, defining a service. Services just need a name * and can optionally inherit from another service using the extends keyword. */ service Calculator extends shared.SharedService { /** * A method definition looks like C code. It has a return type, arguments, * and optionally a list of exceptions that it may throw. Note that argument * lists and exception lists are specified using the exact same syntax as * field lists in struct or exception definitions. */ void ping(), i32 add(1:i32 num1, 2:i32 num2), i32 calculate(1:i32 logid, 2:Work w) throws (1:InvalidOperation ouch), /** * This method has a oneway modifier. That means the client only makes * a request and does not listen for any response at all. Oneway methods * must be void. */ oneway void zip() } /** * That just about covers the basics. Take a look in the test/ folder for more * detailed examples. After you run this file, your generated code shows up * in folders with names gen-. The generated code isn't too scary * to look at. It even has pretty indentation. */