Skip to main content

Ultra fast JSON encoder and decoder for Python

Project description

UltraJSON is an ultra fast JSON encoder and decoder written in pure C with bindings for Python 2.5+ and 3.

For a more painless day to day C/C++ JSON decoder experience please checkout ujson4c, based on UltraJSON.

Please checkout the rest of the projects in the Ultra series:

To install it just run Pip as usual:

$ pip install ujson

Usage

May be used as a drop in replacement for most other JSON parsers for Python:

>>> import ujson
>>> ujson.dumps([{"key": "value"}, 81, True])
'[{"key":"value"},81,true]'
>>> ujson.loads("""[{"key": "value"}, 81, true]""")
[{u'key': u'value'}, 81, True]

Encoder options

encode_html_chars

Used to enable special encoding of “unsafe” HTML characters into safer Unicode sequences. Default is false:

>>> ujson.dumps("<script>John&Doe", encode_html_chars=True)
'"\\u003cscript\\u003eJohn\\u0026Doe"'

ensure_ascii

Limits output to ASCII and escapes all extended characters above 127. Default is true. If your end format supports UTF-8 setting this option to false is highly recommended to save space:

>>> ujson.dumps(u"\xe5\xe4\xf6")
'"\\u00e5\\u00e4\\u00f6"'
>>> ujson.dumps(u"\xe5\xe4\xf6", ensure_ascii=False)
'"\xc3\xa5\xc3\xa4\xc3\xb6"'

double_precision

Controls how many decimals to encode for double or decimal values. Default is 9:

>>> ujson.dumps(math.pi)
'3.1415926536'
>>> ujson.dumps(math.pi, double_precision=1)
'3.1'
>>> ujson.dumps(math.pi, double_precision=0)
'3'
>>> ujson.dumps(math.pi, double_precision=4)
'3.1416'

Decoders options

precise_float

Set to enable usage of higher precision (strtod) function when decoding string to double values. Default is to use fast but less precise builtin functionality:

>>> ujson.loads("4.56")
4.5600000000000005
>>> ujson.loads("4.56", precise_float=True)
4.5599999999999996

Benchmarks

UltraJSON calls/sec compared to three other popular JSON parsers with performance gain specified below each.

Test machine:

Linux version 2.6.32-131.0.15.el6.x86_64

Versions:

  • ujson: 1.21

  • simplejson: 2.6.2

  • cjson: 1.05

  • yajl: 0.3.5

  • Python: Python 2.6.6 (r266:84292, Jul 20 2011, 10:22:43)

ujson

simplejson

cjson

yajl

Array with 256 utf-8 strings

Encode

4090,74

899,39

83,86

3189,86

4,55

48,78

1,28

Decode

863,29

586,15

201,61

352,48

1,47

4,28

2,45

Medium complex object

Encode

9750,37

1377,15

1512,06

3341,91

7,08

6,45

2,92

Decode

5576,75

4247,16

3587,83

2850,13

1,31

1,55

1,96

Array with 256 strings

Encode

17998,01

12954,46

8715,02

15924,35

1,39

2,07

1,13

Decode

14540,71

19696,13

14908,46

9547,14

0,74

0,98

1,52

Array with 256 doubles

Encode

2185,20

1466,87

1956,99

3421,10

1,49

1,12

0,64

Decode

16062,01

8990,50

9743,40

8331,74

1,79

1,65

1,93

Array with 256 True values

Encode

69767,60

25202,56

41145,99

64330,76

2,77

1,70

1,08

Decode

91416,02

56439,97

54918,09

42786,02

1,62

1,66

2,14

Array with 256 dict{string, int} pairs

Encode

11307,54

1830,45

2720,90

7725,56

6,18

4,16

1,46

Decode

8695,94

7572,89

6076,71

5231,32

1,15

1,43

1,66

Dict with 256 arrays with 256 dict

Encode

37,76

4,88

10,49

27,62

7,74

3,60

1,37

Decode

17,70

15,56

11,25

12,00

1,14

1,57

1,47

Project details


Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

ujson-1.33.zip (197.0 kB view details)

Uploaded Source

Built Distributions

ujson-1.33.win32-py3.3.exe (216.8 kB view details)

Uploaded Source

ujson-1.33.win32-py2.6.exe (222.9 kB view details)

Uploaded Source

File details

Details for the file ujson-1.33.zip.

File metadata

  • Download URL: ujson-1.33.zip
  • Upload date:
  • Size: 197.0 kB
  • Tags: Source
  • Uploaded using Trusted Publishing? No

File hashes

Hashes for ujson-1.33.zip
Algorithm Hash digest
SHA256 68cf825f227c82e1ac61e423cfcad923ff734c27b5bdd7174495d162c42c602b
MD5 8148a2493fff78940feab1e11dc0a893
BLAKE2b-256 988c47949a4e454b7ee27cf82a81735414187368fb94bae94de0291903c9881b

See more details on using hashes here.

File details

Details for the file ujson-1.33.win32-py3.3.exe.

File metadata

  • Download URL: ujson-1.33.win32-py3.3.exe
  • Upload date:
  • Size: 216.8 kB
  • Tags: Source
  • Uploaded using Trusted Publishing? No

File hashes

Hashes for ujson-1.33.win32-py3.3.exe
Algorithm Hash digest
SHA256 7c51a4d7ed9795a422adefeefe1a1323bc9ff8921ae460d3cd940cbf4d6d8ea5
MD5 42aaf37018f4e4b83f9d901d1e7ee255
BLAKE2b-256 9daee420ebaa2f7e7ff1f14cd5e1eac65c7606dc7804af53c7062a3030d48e2d

See more details on using hashes here.

File details

Details for the file ujson-1.33.win32-py2.6.exe.

File metadata

  • Download URL: ujson-1.33.win32-py2.6.exe
  • Upload date:
  • Size: 222.9 kB
  • Tags: Source
  • Uploaded using Trusted Publishing? No

File hashes

Hashes for ujson-1.33.win32-py2.6.exe
Algorithm Hash digest
SHA256 883d42387dcc3e0c3abcf741f3ae2f28bcc321dcc367db76d8a9e6c73236ba14
MD5 1500abda31c3bdf8e61ca85365fcdda5
BLAKE2b-256 2b2e528179ca56fa88fde35684df947ce68106179f9bb3d4e27da33bc283e644

See more details on using hashes here.

Supported by

AWS Cloud computing and Security Sponsor Datadog Monitoring Fastly CDN Google Download Analytics Pingdom Monitoring Sentry Error logging StatusPage Status page