Azure OpenAI客户端经APIM访问报404错误排查请求

问题根源 #

1. 路径自动拼接错误
   Azure OpenAI SDK默认会给azure_endpoint拼接/openai前缀，再加上部署和接口路径。但你的APIM端点直接映射到OpenAI的/deployments层级，导致SDK生成的请求路径变成https://xy-apim-XXX.azure-api.net/openai/deployments/...，而APIM上不存在这个路径，触发404。

2. 认证头不匹配
   APIM要求使用Ocp-Apim-Subscription-Key请求头进行身份验证，而SDK默认将api_key放在Authorization: Bearer {key}头中，不符合APIM的认证规则（即使路径正确，也会触发认证错误）。

修正后的代码示例 #

方法一：配置正确端点并覆盖默认请求头 #

from openai import AzureOpenAI

apim_url = "https://xy-apim-XXX.azure-api.net/"
deployment_name = "DEPLOYMENT_NAME"
api_version = "Version"
subscription_key = "YOUR_APIM_SUBSCRIPTION_KEY"

client = AzureOpenAI(
    api_key=subscription_key,
    api_version=api_version,
    azure_endpoint=apim_url,
    # 显式添加APIM要求的订阅密钥头
    default_headers={"Ocp-Apim-Subscription-Key": subscription_key}
)

def get_response_enrich():
    completion = client.chat.completions.create(
        # model参数需与APIM映射的部署名一致
        model=deployment_name,
        messages=[
            {"role": "system", "content": "name a country in europe"},
            {"role": "user", "content": "you're a helpful assistant"}
        ],
        temperature=0,
    )
    return completion.choices[0].message.content

方法二：使用api_base替代azure_endpoint（避免自动拼接前缀） #

from openai import AzureOpenAI

apim_url = "https://xy-apim-XXX.azure-api.net/"
deployment_name = "DEPLOYMENT_NAME"
api_version = "Version"
subscription_key = "YOUR_APIM_SUBSCRIPTION_KEY"

# 使用api_base直接指定APIM根路径，SDK不会额外添加/openai前缀
client = AzureOpenAI(
    api_key=subscription_key,
    api_version=api_version,
    api_base=apim_url,
    default_headers={"Ocp-Apim-Subscription-Key": subscription_key}
)

def get_response_enrich():
    completion = client.chat.completions.create(
        model=deployment_name,
        messages=[
            {"role": "system", "content": "name a country in europe"},
            {"role": "user", "content": "you're a helpful assistant"}
        ],
        temperature=0,
    )
    return completion.choices[0].message.content

关键注意事项 #

• 确保model参数的值与APIM中映射的Azure OpenAI部署名完全一致，不要使用自定义名称。
• 若APIM对路径有特殊映射规则，需调整api_base或azure_endpoint以匹配实际路径结构。

内容的提问来源于stack exchange，提问作者Raha