datasets/submissions_2_parquet_part1.py

   1 #!/usr/bin/env python3
   2
   3 # two stages:
   4 # 1. from gz to arrow parquet (this script)
   5 # 2. from arrow parquet to spark parquet (submissions_2_parquet_part2.py)
   6 from datetime import datetime
   7 from pathlib import Path
   8 from itertools import islice
   9 from helper import find_dumps, open_fileset
  10 import pandas as pd
  11 import pyarrow as pa
  12 import pyarrow.parquet as pq
  13 import fire
  14 import os
  15 import json
  16
  17 def parse_submission(post, names = None):
  18     if names is None:
  19         names = ['id','author','subreddit','title','created_utc','permalink','url','domain','score','ups','downs','over_18','has_media','selftext','retrieved_on','num_comments','gilded','edited','time_edited','subreddit_type','subreddit_id','subreddit_subscribers','name','is_self','stickied','quarantine','error']
  20
  21     try:
  22         post = json.loads(post)
  23     except (ValueError) as e:
  24         #        print(e)
  25         #        print(post)
  26         row = [None for _ in names]
  27         row[-1] = "Error parsing json|{0}|{1}".format(e,post)
  28         return tuple(row)
  29
  30     row = []
  31
  32     for name in names:
  33         if name == 'created_utc' or name == 'retrieved_on':
  34             val = post.get(name,None)
  35             if val is not None:
  36                 row.append(datetime.fromtimestamp(int(post[name]),tz=None))
  37             else:
  38                 row.append(None)
  39         elif name == 'edited':
  40             val = post[name]
  41             if type(val) == bool:
  42                 row.append(val)
  43                 row.append(None)
  44             else:
  45                 row.append(True)
  46                 row.append(datetime.fromtimestamp(int(val),tz=None))
  47         elif name == "time_edited":
  48             continue
  49         elif name == 'has_media':
  50             row.append(post.get('media',None) is not None)
  51
  52         elif name not in post:
  53             row.append(None)
  54         else:
  55             row.append(post[name])
  56     return tuple(row)
  57
  58 def parse_dump(partition):
  59
  60     N=10000
  61     stream = open_fileset([f"/gscratch/comdata/raw_data/reddit_dumps/submissions/{partition}"])
  62     rows = map(parse_submission,stream)
  63     schema = pa.schema([
  64         pa.field('id', pa.string(),nullable=True),
  65         pa.field('author', pa.string(),nullable=True),
  66         pa.field('subreddit', pa.string(),nullable=True),
  67         pa.field('title', pa.string(),nullable=True),
  68         pa.field('created_utc', pa.timestamp('ms'),nullable=True),
  69         pa.field('permalink', pa.string(),nullable=True),
  70         pa.field('url', pa.string(),nullable=True),
  71         pa.field('domain', pa.string(),nullable=True),
  72         pa.field('score', pa.int64(),nullable=True),
  73         pa.field('ups', pa.int64(),nullable=True),
  74         pa.field('downs', pa.int64(),nullable=True),
  75         pa.field('over_18', pa.bool_(),nullable=True),
  76         pa.field('has_media',pa.bool_(),nullable=True),
  77         pa.field('selftext',pa.string(),nullable=True),
  78         pa.field('retrieved_on', pa.timestamp('ms'),nullable=True),
  79         pa.field('num_comments', pa.int64(),nullable=True),
  80         pa.field('gilded',pa.int64(),nullable=True),
  81         pa.field('edited',pa.bool_(),nullable=True),
  82         pa.field('time_edited',pa.timestamp('ms'),nullable=True),
  83         pa.field('subreddit_type',pa.string(),nullable=True),
  84         pa.field('subreddit_id',pa.string(),nullable=True),
  85         pa.field('subreddit_subscribers',pa.int64(),nullable=True),
  86         pa.field('name',pa.string(),nullable=True),
  87         pa.field('is_self',pa.bool_(),nullable=True),
  88         pa.field('stickied',pa.bool_(),nullable=True),
  89         pa.field('quarantine',pa.bool_(),nullable=True),
  90         pa.field('error',pa.string(),nullable=True)])
  91
  92     Path("/gscratch/comdata/output/temp/reddit_submissions.parquet/").mkdir(exist_ok=True,parents=True)
  93
  94     with pq.ParquetWriter(f"/gscratch/comdata/output/temp/reddit_submissions.parquet/{partition}",schema=schema,compression='snappy',flavor='spark') as writer:
  95         while True:
  96             chunk = islice(rows,N)
  97             pddf = pd.DataFrame(chunk, columns=schema.names)
  98             table = pa.Table.from_pandas(pddf,schema=schema)
  99             if table.shape[0] == 0:
 100                 break
 101             writer.write_table(table)
 102
 103         writer.close()
 104
 105 def gen_task_list(dumpdir="/gscratch/comdata/raw_data/reddit_dumps/submissions"):
 106     files = list(find_dumps(dumpdir,base_pattern="RS_20*.*"))
 107     with open("submissions_task_list.sh",'w') as of:
 108         for fpath in files:
 109             partition = os.path.split(fpath)[1]
 110             of.write(f'python3 submissions_2_parquet_part1.py parse_dump {partition}\n')
 111
 112 if __name__ == "__main__":
 113     fire.Fire({'parse_dump':parse_dump,
 114               'gen_task_list':gen_task_list})