fastavro.json_write

json_writer(fo, schema, records, *, write_union_type=True)

Write records to fo (stream) according to schema

Parameters
  • fo (file-like) – Output stream

  • schema (dict) – Writer schema

  • records (iterable) – Records to write. This is commonly a list of the dictionary representation of the records, but it can be any iterable

  • write_union_type (bool (default True)) – Determine whether to write the union type in the json message. If this is set to False the output will be clear json. It may however not be decodable back to avro record by json_read.

Example:

from fastavro import json_writer, parse_schema

schema = {
    'doc': 'A weather reading.',
    'name': 'Weather',
    'namespace': 'test',
    'type': 'record',
    'fields': [
        {'name': 'station', 'type': 'string'},
        {'name': 'time', 'type': 'long'},
        {'name': 'temp', 'type': 'int'},
    ],
}
parsed_schema = parse_schema(schema)

records = [
    {u'station': u'011990-99999', u'temp': 0, u'time': 1433269388},
    {u'station': u'011990-99999', u'temp': 22, u'time': 1433270389},
    {u'station': u'011990-99999', u'temp': -11, u'time': 1433273379},
    {u'station': u'012650-99999', u'temp': 111, u'time': 1433275478},
]

with open('some-file', 'w') as out:
    json_writer(out, parsed_schema, records)