comments_2_parquet_part1.py

   1 #!/usr/bin/env python3
   2 import json
   3 from datetime import datetime
   4 from multiprocessing import Pool
   5 from itertools import islice
   6 from helper import find_dumps, open_fileset
   7 import pandas as pd
   8 import pyarrow as pa
   9 import pyarrow.parquet as pq
  10
  11 globstr_base = "/gscratch/comdata/reddit_dumps/comments/RC_20*"
  12
  13 def parse_comment(comment, names= None):
  14     if names is None:
  15         names = ["id","subreddit","link_id","parent_id","created_utc","author","ups","downs","score","edited","subreddit_type","subreddit_id","stickied","is_submitter","body","error"]
  16
  17     try:
  18         comment = json.loads(comment)
  19     except json.decoder.JSONDecodeError as e:
  20         print(e)
  21         print(comment)
  22         row = [None for _ in names]
  23         row[-1] = "json.decoder.JSONDecodeError|{0}|{1}".format(e,comment)
  24         return tuple(row)
  25
  26     row = []
  27     for name in names:
  28         if name == 'created_utc':
  29             row.append(datetime.fromtimestamp(int(comment['created_utc']),tz=None))
  30         elif name == 'edited':
  31             val = comment[name]
  32             if type(val) == bool:
  33                 row.append(val)
  34                 row.append(None)
  35             else:
  36                 row.append(True)
  37                 row.append(datetime.fromtimestamp(int(val),tz=None))
  38         elif name == "time_edited":
  39             continue
  40         elif name not in comment:
  41             row.append(None)
  42
  43         else:
  44             row.append(comment[name])
  45
  46     return tuple(row)
  47
  48
  49 #    conf = sc._conf.setAll([('spark.executor.memory', '20g'), ('spark.app.name', 'extract_reddit_timeline'), ('spark.executor.cores', '26'), ('spark.cores.max', '26'), ('spark.driver.memory','84g'),('spark.driver.maxResultSize','0'),('spark.local.dir','/gscratch/comdata/spark_tmp')])
  50
  51 dumpdir = "/gscratch/comdata/raw_data/reddit_dumps/comments"
  52
  53 files = list(find_dumps(dumpdir, base_pattern="RC_20*.*"))
  54
  55 pool = Pool(28)
  56
  57 stream = open_fileset(files)
  58
  59 N = 100000
  60
  61 rows = pool.imap_unordered(parse_comment, stream, chunksize=int(N/28))
  62
  63 schema = pa.schema([
  64     pa.field('id', pa.string(), nullable=True),
  65     pa.field('subreddit', pa.string(), nullable=True),
  66     pa.field('link_id', pa.string(), nullable=True),
  67     pa.field('parent_id', pa.string(), nullable=True),
  68     pa.field('created_utc', pa.timestamp('ms'), nullable=True),
  69     pa.field('author', pa.string(), nullable=True),
  70     pa.field('ups', pa.int64(), nullable=True),
  71     pa.field('downs', pa.int64(), nullable=True),
  72     pa.field('score', pa.int64(), nullable=True),
  73     pa.field('edited', pa.bool_(), nullable=True),
  74     pa.field('time_edited', pa.timestamp('ms'), nullable=True),
  75     pa.field('subreddit_type', pa.string(), nullable=True),
  76     pa.field('subreddit_id', pa.string(), nullable=True),
  77     pa.field('stickied', pa.bool_(), nullable=True),
  78     pa.field('is_submitter', pa.bool_(), nullable=True),
  79     pa.field('body', pa.string(), nullable=True),
  80     pa.field('error', pa.string(), nullable=True),
  81 ])
  82
  83 with pq.ParquetWriter("/gscratch/comdata/output/reddit_comments.parquet_temp",schema=schema,compression='snappy',flavor='spark') as writer:
  84     while True:
  85         chunk = islice(rows,N)
  86         pddf = pd.DataFrame(chunk, columns=schema.names)
  87         table = pa.Table.from_pandas(pddf,schema=schema)
  88         if table.shape[0] == 0:
  89             break
  90         writer.write_table(table)
  91
  92     writer.close()