Python如何按image_name分组统计duration总和输出指定格式

你需要对top_duration列表按image_name字段分组，累加同组的duration值，最终输出{总时长, 镜像名}格式的结果，以下是两种可直接运行的实现方式：

方案1：纯原生Python实现（无任何依赖） #

不需要引入额外库，通过字典维护分组累加值即可，兼容性最好。

# 原始输入数据
top_duration = [
    {"duration": 3752, "image_name": "ohcm-designer-orchestration-service"},
    {"duration": 3471, "image_name": "ohcm-designer-orchestration-service"},
    {"duration": 3452, "image_name": "metadata-validations-service"},
    {"duration": 120, "image_name": "metadata-validations-service"},
    {"duration": 114, "image_name": "metadata-validations-service"},
    {"duration": 111, "image_name": "ohcm-metadata-dna-service"},
    {"duration": 102, "image_name": "metadata-validations-service"},
    {"duration": 100, "image_name": "metadata-runtime-proxy-service"},
]

# 遍历列表完成分组累加
sum_map = {}
for item in top_duration:
    img_name = item["image_name"]
    dur = item["duration"]
    if img_name not in sum_map:
        sum_map[img_name] = 0
    sum_map[img_name] += dur

# 转换为要求的格式输出
result = [{total_dur, img_name} for img_name, total_dur in sum_map.items()]

运行后计算结果完全匹配需求：

• metadata-validations-service对应结果为{3788, 'metadata-validations-service'}
• ohcm-designer-orchestration-service对应结果为{7223, 'ohcm-designer-orchestration-service'}
• ohcm-metadata-dna-service对应结果为{111, 'ohcm-metadata-dna-service'}
• metadata-runtime-proxy-service对应结果为{100, 'metadata-runtime-proxy-service'}

方案2：用标准库defaultdict简化逻辑 #

可以引入Python标准库collections中的defaultdict，省去手动判断键是否存在的步骤，代码更简洁：

from collections import defaultdict

# 原始top_duration数据
top_duration = [
    {"duration": 3752, "image_name": "ohcm-designer-orchestration-service"},
    {"duration": 3471, "image_name": "ohcm-designer-orchestration-service"},
    {"duration": 3452, "image_name": "metadata-validations-service"},
    {"duration": 120, "image_name": "metadata-validations-service"},
    {"duration": 114, "image_name": "metadata-validations-service"},
    {"duration": 111, "image_name": "ohcm-metadata-dna-service"},
    {"duration": 102, "image_name": "metadata-validations-service"},
    {"duration": 100, "image_name": "metadata-runtime-proxy-service"},
]

sum_map = defaultdict(int)
for item in top_duration:
    sum_map[item["image_name"]] += item["duration"]

result = [{total_dur, img_name} for img_name, total_dur in sum_map.items()]

注意：Python中{v1, v2}是无序集合结构，如果后续需要按固定位置取值（比如固定第一个元素是总时长、第二个是镜像名），建议将集合替换为元组(total_dur, img_name)，避免集合无序导致的取值错误。

内容的提问来源于stack exchange，提问作者Deep_learner