Mathew Inwood | ea14c0c | 2018-10-05 14:41:03 +0100 | [diff] [blame] | 1 | #!/usr/bin/env python |
| 2 | # |
| 3 | # Copyright (C) 2018 The Android Open Source Project |
| 4 | # |
| 5 | # Licensed under the Apache License, Version 2.0 (the "License"); |
| 6 | # you may not use this file except in compliance with the License. |
| 7 | # You may obtain a copy of the License at |
| 8 | # |
| 9 | # http://www.apache.org/licenses/LICENSE-2.0 |
| 10 | # |
| 11 | # Unless required by applicable law or agreed to in writing, software |
| 12 | # distributed under the License is distributed on an "AS IS" BASIS, |
| 13 | # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 14 | # See the License for the specific language governing permissions and |
| 15 | # limitations under the License. |
| 16 | """ |
| 17 | Merge mutliple CSV files, possibly with different columns, writing to stdout. |
| 18 | """ |
| 19 | |
| 20 | import csv |
| 21 | import sys |
| 22 | |
| 23 | csv_readers = [ |
Artur Satayev | 9430c17 | 2020-01-20 17:35:58 +0000 | [diff] [blame] | 24 | csv.DictReader(open(csv_file, 'r'), delimiter=',', quotechar='|') |
Mathew Inwood | ea14c0c | 2018-10-05 14:41:03 +0100 | [diff] [blame] | 25 | for csv_file in sys.argv[1:] |
| 26 | ] |
| 27 | |
| 28 | # Build union of all columns from source files: |
| 29 | headers = set() |
| 30 | for reader in csv_readers: |
Artur Satayev | 9430c17 | 2020-01-20 17:35:58 +0000 | [diff] [blame] | 31 | headers = headers.union(reader.fieldnames) |
Mathew Inwood | ea14c0c | 2018-10-05 14:41:03 +0100 | [diff] [blame] | 32 | |
| 33 | # Concatenate all files to output: |
Artur Satayev | 9430c17 | 2020-01-20 17:35:58 +0000 | [diff] [blame] | 34 | out = csv.DictWriter(sys.stdout, delimiter=',', quotechar='|', quoting=csv.QUOTE_MINIMAL, |
| 35 | dialect='unix', fieldnames=sorted(headers)) |
Mathew Inwood | ea14c0c | 2018-10-05 14:41:03 +0100 | [diff] [blame] | 36 | out.writeheader() |
| 37 | for reader in csv_readers: |
Artur Satayev | 9430c17 | 2020-01-20 17:35:58 +0000 | [diff] [blame] | 38 | for row in reader: |
| 39 | out.writerow(row) |