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jsaone
This is a tiny wrapper around the standard json library, allowing to read a json file incrementally.
This can be useful for - parsing json streams without waiting for the end of the transmission, - parsing very big json objects without wasting RAM for the json representation itself.
Efficiency
No extensive tests were made (if you make them, let me know), but here are the results (in seconds) obtained in opening a local file with 384650 objects, totalling 174 MB:
| Parser | Iteration 1 | Iteration 2 |
|---|---|---|
| standard (non-incremental) json | 9.511 | 9.273 |
| cythonized jsaone | 19.055 | 18.956 |
| ijson (with yajl2 backend) | 62.250 | 64.538 |
| pure python jsaone | 421.641 | 421.821 |
Those results were obtained with the script “tests/json_load_test.py”.
Clearly those numbers are affected by the speed of the CPU and of the medium. In general the faster the CPU (compared to the storage medium/stream), the fastest will be the standard json compared to incremental ones (including jsaone).
Why "jsaone"
Because it sounds similar to “json”… but the Saône is a (large) stream.
Dependencies
- simplejson (Python 2.5 only)
- for efficiency: cython (at build time)
License
Released under the GPL 3.