jsonl.dumps¶

Serialize an iterable of objects into a JSON Lines formatted string.

Function Signature¶

jsonl.dumps(
    iterable,
    *,
    cls=None,
    **kwargs,
)

Parameters¶

Parameter	Type	Default	Description
`iterable`	`Iterable[Any]`	(required)	Iterable of objects to serialize
`cls`	`type[json.JSONEncoder]` `Callable` or `None`	`json.JSONEncoder`	Custom encoder
`**kwargs`			Additional keyword arguments passed to the `cls` encoder

Returns¶

str — A string with one JSON object per line.

Examples¶

Basic usage¶

import jsonl

data = [{"foo": 1}, {"bar": 2}]
result = jsonl.dumps(data)
print(result)

Output:

{"foo": 1}
{"bar": 2}

With custom serialization¶

import jsonl

data = [{"name": "Alice", "age": 30}, {"name": "Bob", "age": 25}]

# Compact output
result = jsonl.dumps(data, separators=(",", ":"))
print(result)

Output:

{"name":"Alice","age":30}
{"name":"Bob","age":25}

With sorted keys¶

import jsonl

data = [{"z": 1, "a": 2}, {"m": 3, "b": 4}]

result = jsonl.dumps(data, sort_keys=True)
print(result)

Output:

{"a": 2, "z": 1}
{"b": 4, "m": 3}