projektAI/venv/Lib/site-packages/pandas/tests/io/json/test_readlines.py
2021-06-06 22:13:05 +02:00

283 lines
9.1 KiB
Python

from io import StringIO
from pathlib import Path
import pytest
import pandas as pd
from pandas import DataFrame, read_json
import pandas._testing as tm
from pandas.io.json._json import JsonReader
@pytest.fixture
def lines_json_df():
df = DataFrame({"A": [1, 2, 3], "B": [4, 5, 6]})
return df.to_json(lines=True, orient="records")
def test_read_jsonl():
# GH9180
result = read_json('{"a": 1, "b": 2}\n{"b":2, "a" :1}\n', lines=True)
expected = DataFrame([[1, 2], [1, 2]], columns=["a", "b"])
tm.assert_frame_equal(result, expected)
def test_read_jsonl_unicode_chars():
# GH15132: non-ascii unicode characters
# \u201d == RIGHT DOUBLE QUOTATION MARK
# simulate file handle
json = '{"a": "foo”", "b": "bar"}\n{"a": "foo", "b": "bar"}\n'
json = StringIO(json)
result = read_json(json, lines=True)
expected = DataFrame([["foo\u201d", "bar"], ["foo", "bar"]], columns=["a", "b"])
tm.assert_frame_equal(result, expected)
# simulate string
json = '{"a": "foo”", "b": "bar"}\n{"a": "foo", "b": "bar"}\n'
result = read_json(json, lines=True)
expected = DataFrame([["foo\u201d", "bar"], ["foo", "bar"]], columns=["a", "b"])
tm.assert_frame_equal(result, expected)
def test_to_jsonl():
# GH9180
df = DataFrame([[1, 2], [1, 2]], columns=["a", "b"])
result = df.to_json(orient="records", lines=True)
expected = '{"a":1,"b":2}\n{"a":1,"b":2}\n'
assert result == expected
df = DataFrame([["foo}", "bar"], ['foo"', "bar"]], columns=["a", "b"])
result = df.to_json(orient="records", lines=True)
expected = '{"a":"foo}","b":"bar"}\n{"a":"foo\\"","b":"bar"}\n'
assert result == expected
tm.assert_frame_equal(read_json(result, lines=True), df)
# GH15096: escaped characters in columns and data
df = DataFrame([["foo\\", "bar"], ['foo"', "bar"]], columns=["a\\", "b"])
result = df.to_json(orient="records", lines=True)
expected = '{"a\\\\":"foo\\\\","b":"bar"}\n{"a\\\\":"foo\\"","b":"bar"}\n'
assert result == expected
tm.assert_frame_equal(read_json(result, lines=True), df)
def test_to_jsonl_count_new_lines():
# GH36888
df = DataFrame([[1, 2], [1, 2]], columns=["a", "b"])
actual_new_lines_count = df.to_json(orient="records", lines=True).count("\n")
expected_new_lines_count = 2
assert actual_new_lines_count == expected_new_lines_count
@pytest.mark.parametrize("chunksize", [1, 1.0])
def test_readjson_chunks(lines_json_df, chunksize):
# Basic test that read_json(chunks=True) gives the same result as
# read_json(chunks=False)
# GH17048: memory usage when lines=True
unchunked = read_json(StringIO(lines_json_df), lines=True)
with read_json(StringIO(lines_json_df), lines=True, chunksize=chunksize) as reader:
chunked = pd.concat(reader)
tm.assert_frame_equal(chunked, unchunked)
def test_readjson_chunksize_requires_lines(lines_json_df):
msg = "chunksize can only be passed if lines=True"
with pytest.raises(ValueError, match=msg):
with pd.read_json(StringIO(lines_json_df), lines=False, chunksize=2) as _:
pass
def test_readjson_chunks_series():
# Test reading line-format JSON to Series with chunksize param
s = pd.Series({"A": 1, "B": 2})
strio = StringIO(s.to_json(lines=True, orient="records"))
unchunked = pd.read_json(strio, lines=True, typ="Series")
strio = StringIO(s.to_json(lines=True, orient="records"))
with pd.read_json(strio, lines=True, typ="Series", chunksize=1) as reader:
chunked = pd.concat(reader)
tm.assert_series_equal(chunked, unchunked)
def test_readjson_each_chunk(lines_json_df):
# Other tests check that the final result of read_json(chunksize=True)
# is correct. This checks the intermediate chunks.
with pd.read_json(StringIO(lines_json_df), lines=True, chunksize=2) as reader:
chunks = list(reader)
assert chunks[0].shape == (2, 2)
assert chunks[1].shape == (1, 2)
def test_readjson_chunks_from_file():
with tm.ensure_clean("test.json") as path:
df = DataFrame({"A": [1, 2, 3], "B": [4, 5, 6]})
df.to_json(path, lines=True, orient="records")
with pd.read_json(path, lines=True, chunksize=1) as reader:
chunked = pd.concat(reader)
unchunked = pd.read_json(path, lines=True)
tm.assert_frame_equal(unchunked, chunked)
@pytest.mark.parametrize("chunksize", [None, 1])
def test_readjson_chunks_closes(chunksize):
with tm.ensure_clean("test.json") as path:
df = DataFrame({"A": [1, 2, 3], "B": [4, 5, 6]})
df.to_json(path, lines=True, orient="records")
reader = JsonReader(
path,
orient=None,
typ="frame",
dtype=True,
convert_axes=True,
convert_dates=True,
keep_default_dates=True,
numpy=False,
precise_float=False,
date_unit=None,
encoding=None,
lines=True,
chunksize=chunksize,
compression=None,
nrows=None,
)
with reader:
reader.read()
assert (
reader.handles.handle.closed
), f"didn't close stream with chunksize = {chunksize}"
@pytest.mark.parametrize("chunksize", [0, -1, 2.2, "foo"])
def test_readjson_invalid_chunksize(lines_json_df, chunksize):
msg = r"'chunksize' must be an integer >=1"
with pytest.raises(ValueError, match=msg):
with pd.read_json(
StringIO(lines_json_df), lines=True, chunksize=chunksize
) as _:
pass
@pytest.mark.parametrize("chunksize", [None, 1, 2])
def test_readjson_chunks_multiple_empty_lines(chunksize):
j = """
{"A":1,"B":4}
{"A":2,"B":5}
{"A":3,"B":6}
"""
orig = DataFrame({"A": [1, 2, 3], "B": [4, 5, 6]})
test = pd.read_json(j, lines=True, chunksize=chunksize)
if chunksize is not None:
with test:
test = pd.concat(test)
tm.assert_frame_equal(orig, test, obj=f"chunksize: {chunksize}")
def test_readjson_unicode(monkeypatch):
with tm.ensure_clean("test.json") as path:
monkeypatch.setattr("_bootlocale.getpreferredencoding", lambda l: "cp949")
with open(path, "w", encoding="utf-8") as f:
f.write('{"£©µÀÆÖÞßéöÿ":["АБВГДабвгд가"]}')
result = read_json(path)
expected = DataFrame({"£©µÀÆÖÞßéöÿ": ["АБВГДабвгд가"]})
tm.assert_frame_equal(result, expected)
@pytest.mark.parametrize("nrows", [1, 2])
def test_readjson_nrows(nrows):
# GH 33916
# Test reading line-format JSON to Series with nrows param
jsonl = """{"a": 1, "b": 2}
{"a": 3, "b": 4}
{"a": 5, "b": 6}
{"a": 7, "b": 8}"""
result = pd.read_json(jsonl, lines=True, nrows=nrows)
expected = DataFrame({"a": [1, 3, 5, 7], "b": [2, 4, 6, 8]}).iloc[:nrows]
tm.assert_frame_equal(result, expected)
@pytest.mark.parametrize("nrows,chunksize", [(2, 2), (4, 2)])
def test_readjson_nrows_chunks(nrows, chunksize):
# GH 33916
# Test reading line-format JSON to Series with nrows and chunksize param
jsonl = """{"a": 1, "b": 2}
{"a": 3, "b": 4}
{"a": 5, "b": 6}
{"a": 7, "b": 8}"""
with read_json(jsonl, lines=True, nrows=nrows, chunksize=chunksize) as reader:
chunked = pd.concat(reader)
expected = DataFrame({"a": [1, 3, 5, 7], "b": [2, 4, 6, 8]}).iloc[:nrows]
tm.assert_frame_equal(chunked, expected)
def test_readjson_nrows_requires_lines():
# GH 33916
# Test ValuError raised if nrows is set without setting lines in read_json
jsonl = """{"a": 1, "b": 2}
{"a": 3, "b": 4}
{"a": 5, "b": 6}
{"a": 7, "b": 8}"""
msg = "nrows can only be passed if lines=True"
with pytest.raises(ValueError, match=msg):
pd.read_json(jsonl, lines=False, nrows=2)
def test_readjson_lines_chunks_fileurl(datapath):
# GH 27135
# Test reading line-format JSON from file url
df_list_expected = [
DataFrame([[1, 2]], columns=["a", "b"], index=[0]),
DataFrame([[3, 4]], columns=["a", "b"], index=[1]),
DataFrame([[5, 6]], columns=["a", "b"], index=[2]),
]
os_path = datapath("io", "json", "data", "line_delimited.json")
file_url = Path(os_path).as_uri()
with pd.read_json(file_url, lines=True, chunksize=1) as url_reader:
for index, chuck in enumerate(url_reader):
tm.assert_frame_equal(chuck, df_list_expected[index])
def test_chunksize_is_incremental():
# See https://github.com/pandas-dev/pandas/issues/34548
jsonl = (
"""{"a": 1, "b": 2}
{"a": 3, "b": 4}
{"a": 5, "b": 6}
{"a": 7, "b": 8}\n"""
* 1000
)
class MyReader:
def __init__(self, contents):
self.read_count = 0
self.stringio = StringIO(contents)
def read(self, *args):
self.read_count += 1
return self.stringio.read(*args)
def __iter__(self):
self.read_count += 1
return iter(self.stringio)
reader = MyReader(jsonl)
assert len(list(pd.read_json(reader, lines=True, chunksize=100))) > 1
assert reader.read_count > 10