5个Lang:2-LangFuse基本使用

本文来介绍另一款生产级AI应用维护平台:LangFuse,它是开源的,是LangSmith 的平替,并且它可集成 LangChain,同时也可直接对接 OpenAI API。

官方网站:https://langfuse.com/

项目地址:https://github.com/langfuse

0. 环境准备

(1)先注册,登录,官网地址在上面

(2)创建Project

【图片】

(3)生成私钥和公钥

(4)本地安装 langfuse

!pip install langfuse openai
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# 设置OpenAI KEY环境变量
import os
import getpass
os.environ['OPENAI_API_KEY'] = getpass.getpass('OpenAI API Key:')
OpenAI API Key:··········

1. 开始使用

LangFuse有两种集成方式:

OpenAI API集成

LangChain集成

在运行之前,先将你的公钥和私钥放到环境变量中。例如.env文件中加入:

# 把如下内容加入到.env文件中,也可以使用如下方式添加环境变量
LANGFUSE_SECRET_KEY = "sk-lf-xxxxx"
LANGFUSE_PUBLIC_KEY = "pk-lf-xxxxx"
# 添加私钥
os.environ['LANGFUSE_SECRET_KEY'] = getpass.getpass('LANGFUSE_SECRET_KEY:')
LANGFUSE_SECRET_KEY:··········
# 添加公钥
os.environ['LANGFUSE_PUBLIC_KEY'] = getpass.getpass('LANGFUSE_PUBLIC_KEY')
LANGFUSE_PUBLIC_KEY··········

这样才能使你的程序与你在LangFuse官网上建立的跟踪项目链接起来。

1.1 OpenAI API集成方式

集成步骤:

(1)引入langfuse中的openai:from langfuse.openai import openai,用这个才能集成langfuse

(2)使用Langfuse实例的trace函数,传入一些个人和项目信息

(3)openai接口调用,多了一个trace_id参数

from datetime import datetime
from langfuse.openai import openai ## 1. 引入langfuse中的openai
from langfuse import Langfuse
import os

## 2. 使用Langfuse实例的trace函数,传入一些个人和项目信息
trace = Langfuse().trace(
    name = "hello-world",
    user_id = "Arron",
    release = "v0.0.1"
)

completion = openai.chat.completions.create(
  name="hello-world",
  model="gpt-3.5-turbo",
  messages=[
      {"role": "user", "content": "对我说'Hello, World!'"}
  ],
  temperature=0,
  trace_id=trace.id, ## 3. openai接口调用,多了一个trace_id参数
)

print(completion.choices[0].message.content)

## 输出:Hello, World!
Hello, World!

运行之后,看下LangFuse平台的调用情况

【图片】

1.2 LangChain集成方式

通过 LangChain 的回调集成。

集成步骤:

(1)从langfuse中引入CallbackHandler:from langfuse.callback import CallbackHandler

(2)在CallbackHandler中设置个人和项目信息

(3)正常创建LangChain应用和流程

(4)invoke时,将CallbackHandler填入config参数中:config={“callbacks”:[handler]}

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from langfuse.callback import CallbackHandler

handler = CallbackHandler(
    trace_name="SayHello",
    user_id="Arron",
)

from langchain_openai import ChatOpenAI
from langchain.prompts import PromptTemplate
from langchain.schema.output_parser import StrOutputParser
from langchain.schema.runnable import RunnablePassthrough
from langchain.schema import HumanMessage
from langchain.prompts.chat import HumanMessagePromptTemplate
from langchain.prompts import ChatPromptTemplate

model = ChatOpenAI(model="gpt-3.5-turbo-0613")

prompt_template = """
我的名字叫【{name}】,我的个人介绍是【{description}】。
请根据我的名字和介绍,帮我想一段有吸引力的自我介绍的句子,以此来吸引读者关注和点赞我的账号。
"""
prompt = ChatPromptTemplate.from_messages([
    HumanMessagePromptTemplate.from_template(prompt_template)
])

# 定义输出解析器
parser = StrOutputParser()

chain = (
    {"name":RunnablePassthrough(), "description":RunnablePassthrough() } ## 这里是给prompt的输入,两个参数
    | prompt
    | model
    | parser
)

## invoke的第一个参数,传入json格式的参数,key与prompt中的参数名一致
response = chain.invoke({'name': 'Arron', 'description': '热爱AI,持续学习,持续干货输出'}, config={"callbacks":[handler]})
print(response)
/usr/local/lib/python3.10/dist-packages/langchain_core/_api/beta_decorator.py:87: LangChainBetaWarning: The function `loads` is in beta. It is actively being worked on, so the API may change.
  warn_beta(


大家好,我是Arron,一个热爱AI的学习者,不仅如此,我还持续输出干货。无论是深入探讨AI技术的最新进展,还是分享实用的学习方法,我都努力为大家提供有价值的内容。如果你也对AI充满热情,想要不断学习和成长,那么请关注我的账号,我们一起探索AI的无限可能!

运行之后看下LangFuse平台,应该能看到你的项目和调用了。

【图片】

2. 详细信息查看 - Traces页面

使用Traces页面,可以看到你每次程序运行的详细过程,包括每一步的输入、输出、耗时、token数等。

(1)进入Traces,可以看到你所有的运行目录。

【图片】

(2)点击上方的任一ID,可以进入到本次运行的详细跟踪页面。该页面包含了本次运行的过程:详细执行步骤(右侧)。点击任一步骤,可以在左侧看到本步骤的输入和输出,以及耗时和token数(图中的145->133表示输入145token,输出133token)。

在这里插入图片描述

有了这个页面,你可以轻易的跟踪输入输出是否有问题,哪一步有问题,从而更好的调优你的程序。这个比自己打日志的信息更详细和更好用多了。

<think> 我们正在讨论的是commons-lang:commons-lang这个jar包的作用。根据Apache Commons Lang项目的官方描述,这个库提供了一系列针对Java标准库的实用工具类和方法,主要目的是填补Java标准库(java.lang)的不足,提供更多的工具和功能,使得开发者能够更高效地进行开发。 主要作用包括: 1. **字符串处理**:提供了StringUtils类,包含大量字符串操作方法,如空值安全的判断、截取、反转、拆分、连接等。 2. **数值处理**:NumberUtils类提供数字转换、判断等。 3. **对象操作**:ObjectUtils类提供对象的null安全操作,如默认值处理、比较等。 4. **日期时间处理**:DateUtils和DateFormatUtils类提供日期格式化和计算(如日期加减、比较等)。 5. **数组操作**:ArrayUtils类提供数组的合并、子数组、反转、查找等。 6. **系统属性**:SystemUtils类用于获取系统属性(如操作系统类型、Java版本等)。 7. **异常处理**:ExceptionUtils类提供异常堆栈信息的处理。 8. **随机数生成**:RandomUtils和RandomStringUtils类提供更便捷的随机数生成。 9. **构建器模式**:ToStringBuilder、EqualsBuilder、HashCodeBuilder等帮助生成toString、equals和hashCode方法。 此外,它还包含一些其他工具类,如SerializationUtils(序列化工具)、EnumUtils(枚举工具)等。 这个库在Java开发中被广泛使用,特别是在需要大量基础工具类支持的场景下,可以避免重复造轮子。 下面我们以代码示例来展示一些常用功能: 示例1:使用StringUtils处理字符串 ```java import org.apache.commons.lang.StringUtils; public class StringExample { public static void main(String[] args) { // 判断字符串是否为空(null或空字符串) String str = null; System.out.println(StringUtils.isEmpty(str)); // 输出: true // 判断字符串是否为空白(null、空字符串或仅包含空白字符) System.out.println(StringUtils.isBlank(" ")); // 输出: true // 反转字符串 System.out.println(StringUtils.reverse("hello")); // 输出: olleh // 截取字符串 System.out.println(StringUtils.substring("hello world", 6)); // 输出: world } } ``` 示例2使用DateUtils进行日期操作 ```java import org.apache.commons.lang.time.DateUtils; import java.util.Calendar; import java.util.Date; public class DateExample { public static void main(String[] args) { Date now = new Date(); // 加一天 Date tomorrow = DateUtils.addDays(now, 1); // 减一个月 Date lastMonth = DateUtils.addMonths(now, -1); // 设置时间为当天的开始(00:00:00) Date startOfDay = DateUtils.truncate(now, Calendar.DATE); } } ``` 示例3:使用ArrayUtils操作数组 ```java import org.apache.commons.lang.ArrayUtils; public class ArrayExample { public static void main(String[] args) { int[] array = {1, 2, 3}; // 添加元素到数组 int[] newArray = ArrayUtils.add(array, 4); // [1,2,3,4] // 反转数组 ArrayUtils.reverse(newArray); // [4,3,2,1] // 查找元素 int index = ArrayUtils.indexOf(newArray, 3); // 1 } } ``` 需要注意的是,Apache Commons Lang有两个主要版本:2.x和3.x。其中,2.x的包名为`org.apache.commons.lang`,而3.x的包名为`org.apache.commons.lang3`。我们这里讨论的是2.x版本(commons-lang),而3.x版本(commons-lang3)是向后不兼容的升级,增加了一些新特性并删除了一些过时的方法。 因此,在选择版本时,需要根据项目需求来决定。对于新项目,推荐使用commons-lang3。 综上所述,commons-lang:commons-lang jar包的作用是提供Java标准库的扩展工具类,帮助开发者更高效地完成常见任务。 相关问题: 1. commons-lang和commons-lang3有什么区别? 2. 如何在Maven项目中引入commons-lang? 3. StringUtils类有哪些常用的字符串操作方法? 4. 如何用ToStringBuilder生成对象的toString方法? </think> ### `commons-lang:commons-lang` JAR 包的核心作用 `commons-lang` 是 **Apache Commons Lang** 库的核心组件,提供对 Java 标准库(`java.lang`)的扩展工具类,主要作用包括: #### 1. **增强基础数据类型操作** - **字符串处理**:空值安全操作(如 `StringUtils.isBlank()`)、截取/反转/拆分等[^1] ```java // 示例:安全判断空字符串 StringUtils.isBlank(null); // true StringUtils.isBlank(" "); // true ``` - **数值处理**:类型安全转换(`NumberUtils.toInt()`)、范围检查等 - **数组工具**:高效合并/查找/反转(`ArrayUtils.addAll()`) #### 2. **对象操作增强** - **空值安全处理**:`ObjectUtils.defaultIfNull()` 避免 NPE - **对象比较**:深度比较 `EqualsBuilder.reflectionEquals()` - **哈希码生成**:`HashCodeBuilder` 自动生成合规的 `hashCode()` ```java // 自动生成 hashCode public int hashCode() { return new HashCodeBuilder(17, 37) .append(name) .append(age) .toHashCode(); } ``` #### 3. **日期时间工具** - **日期计算**:`DateUtils.addDays()` 实现安全日期加减 - **格式化/解析**:线程安全的 `DateFormatUtils` 替代 `SimpleDateFormat` ```java String dateStr = DateFormatUtils.ISO_DATE_FORMAT.format(new Date()); ``` #### 4. **系统与环境工具** - **系统属性**:`SystemUtils` 获取 OS/JVM 信息(如 `SystemUtils.IS_JAVA_1_8`) - **随机生成**:`RandomStringUtils` 生成随机字符串/UUID #### 5. **异常处理工具** - **异常链解析**:`ExceptionUtils.getRootCause()` 快速定位根本原因 - **堆栈跟踪**:`ExceptionUtils.getStackTrace()` 转字符串 --- ### 典型应用场景 - 🔧 **减少样板代码**:自动生成 `equals()`/`hashCode()`/`toString()` - 🛡️ **防御式编程**:空值检查、参数验证(`Validate.notNull()`) - ⏱️ **日期安全操作**:避免 `Calendar` 复杂操作 - 📦 **数据转换**:类型转换(`String` ↔ 数字/日期) --- ### 版本说明 - **`commons-lang 2.x`**:传统版本(包路径 `org.apache.commons.lang`) - **`commons-lang3 3.x`**:升级版(包路径 `org.apache.commons.lang3`),推荐新项目使用 --- ### Maven 依赖示例 ```xml <!-- 传统版本 --> <dependency> <groupId>commons-lang</groupId> <artifactId>commons-lang</artifactId> <version>2.6</version> </dependency> <!-- 新版推荐 --> <dependency> <groupId>org.apache.commons</groupId> <artifactId>commons-lang3</artifactId> <version>3.12.0</version> </dependency> ``` --- ### 相关问题 1. `commons-lang` 和 `commons-lang3` 有哪些主要区别?[^1] 2. 如何用 `StringUtils` 高效处理中文字符串? 3. `EqualsBuilder` 在深度比较对象时有哪些性能陷阱? 4. 为什么 `DateFormatUtils` 比 `SimpleDateFormat` 更安全? 5. 如何用 `RandomStringUtils` 生成符合密码学要求的随机字符串
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