- 新增 data_prepare.py 文件,用于初始化和处理电影评分数据 - 实现了从 HDFS 读取 ratings 和 movies 数据的功能 - 提供了数据解析和缓存的逻辑,为后续处理做准备
40 lines
1.3 KiB
Python
40 lines
1.3 KiB
Python
from pyspark import SparkContext, SparkConf
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import os
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# 设置 Java 环境变量
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os.environ['JAVA_HOME'] = '/opt/module/jdk1.8.0_171'
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# 解析 ratings 行为 (userID, movieID, rating)
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def get_ratings_tuple(entry):
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user, movie, rating, _ = entry.split('::')
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return int(user), int(movie), float(rating)
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# 解析 movies 行为 (movieID, title)
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def get_movie_tuple(entry):
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mid, title, _ = entry.split('::')
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return int(mid), title
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# 用于排序时生成确定性键
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def sort_key(rec):
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score, name = rec
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return f"{score:06.3f} {name}"
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# 初始化并返回 ratingsRDD, moviesRDD
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def init_rdds(sc, hdfs_base='hdfs://master:9000/user/root/als_movie'):
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ratings_path = f"{hdfs_base}/ratings.txt"
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movies_path = f"{hdfs_base}/movies.dat"
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raw_r = sc.textFile(ratings_path).repartition(2)
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raw_m = sc.textFile(movies_path)
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ratings_rdd = raw_r.map(get_ratings_tuple).cache()
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movies_rdd = raw_m.map(get_movie_tuple).cache()
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return ratings_rdd, movies_rdd
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if __name__ == '__main__':
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conf = SparkConf().setMaster('spark://master:7077').setAppName('als_movie')
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sc = SparkContext.getOrCreate(conf)
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sc.setLogLevel('ERROR')
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rdd_ratings, rdd_movies = init_rdds(sc)
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print(f"Ratings count: {rdd_ratings.count()}")
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print(f"Movies count: {rdd_movies.count()}")
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sc.stop() |