流式迭代器
使用集合让一切井井有条
根据您的偏好保存内容并对其进行分类。
调用 GoogleAdsService.search_stream
时,系统会返回流式响应迭代器。此迭代器在使用时应与 GoogleAdsService
客户端保持在同一作用域内,以避免出现数据流中断或内存段错误。这是因为,当打开的 GoogleAdsService
对象超出范围时,gRPC Channel
对象会被垃圾回收。如果在对 search_stream
的结果进行迭代时,GoogleAdsService
对象已不在作用域内,则 Channel
对象可能已被销毁,导致迭代器尝试检索下一个值时出现未定义的行为。
以下代码演示了流式迭代器的错误用法:
def stream_response(client, customer_id, query):
return client.get_service("GoogleAdsService", version="v21").search_stream(customer_id, query=query)
def main(client, customer_id):
query = "SELECT campaign.name FROM campaign LIMIT 10"
response = stream_response(client, customer_id, query=query)
# Access the iterator in a different scope from where the service object was created.
try:
for batch in response:
# Iterate through response, expect undefined behavior.
在上述代码中,GoogleAdsService
对象是在与迭代器访问范围不同的范围内创建的。因此,在迭代器使用整个响应之前,Channel
对象可能会被销毁。
相反,流式迭代器应与 GoogleAdsService
客户端保持在同一作用域内,只要它正在使用:
def main(client, customer_id):
ga_service = client.get_service("GoogleAdsService", version="v21")
query = "SELECT campaign.name FROM campaign LIMIT 10"
response = ga_service.search_stream(customer_id=customer_id, query=query)
# Access the iterator in the same scope as where the service object was created.
try:
for batch in response:
# Successfully iterate through response.
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最后更新时间 (UTC):2025-08-27。
[null,null,["最后更新时间 (UTC):2025-08-27。"],[[["\u003cp\u003eWhen using \u003ccode\u003eGoogleAdsService.search_stream\u003c/code\u003e, the streaming response iterator must remain in the same scope as the \u003ccode\u003eGoogleAdsService\u003c/code\u003e client to prevent stream disruptions or segmentation faults.\u003c/p\u003e\n"],["\u003cp\u003eThis is because the underlying gRPC \u003ccode\u003eChannel\u003c/code\u003e object can be garbage-collected if the \u003ccode\u003eGoogleAdsService\u003c/code\u003e object goes out of scope before the iterator is fully consumed.\u003c/p\u003e\n"],["\u003cp\u003eAccessing the iterator in a different scope may lead to undefined behavior as the \u003ccode\u003eChannel\u003c/code\u003e might be destroyed prematurely.\u003c/p\u003e\n"],["\u003cp\u003eEnsure the iterator is used within the same scope where the \u003ccode\u003eGoogleAdsService\u003c/code\u003e object is created to guarantee successful iteration through the response.\u003c/p\u003e\n"]]],[],null,["# Streaming Iterators\n\nWhen calling\n[`GoogleAdsService.search_stream`](/google-ads/api/reference/rpc/v21/GoogleAdsService/SearchStream),\na streaming response iterator is returned. This iterator should remain in the\nsame scope as the `GoogleAdsService` client while being used in order to avoid\nbroken streams or segmentation faults. This is because the gRPC `Channel` object\nis garbage-collected once the open `GoogleAdsService` object goes out of scope.\nIf the `GoogleAdsService` object is no longer in scope by the time the iteration\noccurs on the result of `search_stream`, the `Channel` object may already be\ndestroyed, causing undefined behavior when the iterator attempts to retrieve the\nnext value.\n\nThe following code demonstrates *incorrect* usage of streaming iterators: \n\n def stream_response(client, customer_id, query):\n return client.get_service(\"GoogleAdsService\", version=\"v21\").search_stream(customer_id, query=query)\n\n def main(client, customer_id):\n query = \"SELECT campaign.name FROM campaign LIMIT 10\"\n response = stream_response(client, customer_id, query=query)\n # Access the iterator in a different scope from where the service object was created.\n try:\n for batch in response:\n # Iterate through response, expect undefined behavior.\n\nIn the above code, the `GoogleAdsService` object is created within a different\nscope from where the iterator is accessed. As a result, the `Channel` object may\nbe destroyed before the iterator consumes the entire response.\n\nInstead, the streaming iterator should remain in the same scope as the\n`GoogleAdsService` client for as long as it is being used: \n\n def main(client, customer_id):\n ga_service = client.get_service(\"GoogleAdsService\", version=\"v21\")\n query = \"SELECT campaign.name FROM campaign LIMIT 10\"\n response = ga_service.search_stream(customer_id=customer_id, query=query)\n # Access the iterator in the same scope as where the service object was created.\n try:\n for batch in response:\n # Successfully iterate through response."]]