A flexible json diff framework for minimalist.
JYCM = Json You-Cha-Ma (「is there a difference」in Chinese)
Also see a Javascript Implementation
See https://eggachecat.github.io/jycm-json-diff-viewer for a live demo.
-
- how results are reported in JYCM is learnt from this amazing framework.
- how TreeLevel is designed in JYCM is learnt from this amazing framework.
-
- Fuzzy matching part of JYCM is learnt from this amazing framework.
pip install jycm
Yes! JYCM has a rendering tool out of the box!
python -m jycm --help
# Usage: python -m jycm [OPTIONS]
# Options:
# --interactive Enter interactive mode
# --left TEXT Left Json
# --right TEXT Right Json
# --rules TEXT Rules
# --output TEXT The folder where the results will be dumped.
# --open Open the browser; This is valid only if you specify the
# output parameter.
# --help Show this message and exit.Use
- mac/linux
python -m jycm --show \
--left="{\"normal-string\":\"aaaaa\",\"ignore_me-string\":\"aaaaa\",\"normal-list-1\":[{\"val\":1},{\"val\":2},{\"val\":3},{\"val\":4},{\"val\":5}],\"set_in_set\":[{\"id\":1,\"label\":\"label:1\",\"set\":[1,2,3,4,5]},{\"id\":2,\"label\":\"label:2\",\"set\":[4,5,6,7,8]}]}" \
--right="{\"normal-string\":\"bbbbb\",\"ignore_me-string\":\"bbbbb\",\"normal-list-1\":[{\"val\":1},{\"val\":9},{\"val\":3},{\"val\":8},{\"what\":5}],\"set_in_set\":[{\"id\":2,\"label\":\"label:2\",\"set\":[6,5,4,7]},{\"id\":1,\"label\":\"label:1\",\"set\":[3,2,1,4,8,9]}]}" \
--rules="[{\"operation\":\"ignore\",\"value\":\"^ignore_me.*\"},{\"value\":\"^set_in_set$\",\"operation\":\"operator:list:ignoreOrder\"},{\"value\":\"set_in_set->\\\\[\\\\d+\\\\]->set\",\"operation\":\"operator:list:ignoreOrder\"}]" \
--left_title="Left Title" \
--right_title="Right Title"- or on windows:
python -m jycm --show --left="{'normal-string': 'aaaaa', 'ignore_me-string': 'aaaaa', 'normal-list-1': [{'val': 1}, {'val': 2}, {'val': 3}, {'val': 4}, {'val': 5}], 'set_in_set': [{'id': 1, 'label': 'label:1', 'set': [1, 2, 3, 4, 5]}, {'id': 2, 'label': 'label:2', 'set': [4, 5, 6, 7, 8]}]}" --right="{'normal-string': 'bbbbb', 'ignore_me-string': 'bbbbb', 'normal-list-1': [{'val': 1}, {'val': 9}, {'val': 3}, {'val': 8}, {'what': 5}], 'set_in_set': [{'id': 2, 'label': 'label:2', 'set': [6, 5, 4, 7]}, {'id': 1, 'label': 'label:1', 'set': [3, 2, 1, 4, 8, 9]}]}" --rules="[{'operation': 'ignore', 'value': '^ignore_me.*'}, {'value': '^set_in_set$', 'operation': 'operator:list:ignoreOrder'}, {'value': 'set_in_set->\\[\\d+\\]->set', 'operation': 'operator:list:ignoreOrder'}]"
- when the json are too large you can pass file path
python -m jycm --show --left_file /xxxx/your_left.json --right_file ~/xxxx/your_right.jsonthen you will see a popup like this:
You can play with cli using:
python -m jycm --interactiveHere's some examples showing you what you can do with JYCM. Only the results without configuration are shown below. (in case you wonder why things are not consistence here)
Kindly suggestion from @TonisPiip
- Why you want
no_pairs=Trueinycm.to_dict(no_pairs=True)?pairsare for rendering purpose (you can see the usage here at react-jycm-viewer)- usually
pairsare pretty large json (especially for some relocation diff) - so if you just want to get the diff you don't need
pairs
Diff two json objects are easy:
Basically you do this:
from jycm.jycm import YouchamaJsonDiffer
left = {} # your json
right = {} # your json
ycm = YouchamaJsonDiffer(left, right)
diff_result = ycm.get_diff()
"""
ycm.get_diff()
are the same as
ycm.diff()
ycm.to_dict*(
"""from jycm.helper import make_ignore_order_func
from jycm.jycm import YouchamaJsonDiffer
from jycm.helper import dump_html_output, open_url
from jycm.jycm import YouchamaJsonDiffer
left = {
"a": 1,
"b": 2,
"d": "12345",
"f": False,
"e": [
{"x": 1, "y": 1},
{"x": 2, "y": 2},
{"x": 3, "y": 3},
{"x": 4, "y": 4},
]
}
right = {
"a": 1,
"b": 3,
"c": 4,
"f": True,
"e": [
{"x": 0, "y": 1},
{"x": 2, "y": 2},
{"x": 3, "y": 3},
{"x": 5, "y": 5},
]
}
ycm = YouchamaJsonDiffer(left, right)
diff_result = ycm.get_diff() # new API
# legacy usage:
# ycm.diff()
# diff_result = ycm.to_dict()
# you can find generated html in the folder
output_dir = "/Users/xxx/jycm-example-1"
# you can directly view it by clicking the index.html file inside the folder
url = dump_html_output(left, right, diff_result, output_dir)
# if you want to open it from python
open_url(url)
expected = {
'dict:add': [
{'left': '__NON_EXIST__',
'left_path': '',
'right': 4,
'right_path': 'c'}
],
'dict:remove': [
{'left': '12345',
'left_path': 'd',
'right': '__NON_EXIST__',
'right_path': ''}
],
'list:add': [
{'left': '__NON_EXIST__',
'left_path': '',
'right': {'x': 5, 'y': 5},
'right_path': 'e->[3]'}
],
'list:remove': [
{'left': {'x': 4, 'y': 4},
'left_path': 'e->[3]',
'right': '__NON_EXIST__',
'right_path': ''}
],
'value_changes': [
{'left': 2,
'left_path': 'b',
'new': 3,
'old': 2,
'right': 3,
'right_path': 'b'},
{'left': 1,
'left_path': 'e->[0]->x',
'new': 0,
'old': 1,
'right': 0,
'right_path': 'e->[0]->x'},
{'left': False,
'left_path': 'f',
'new': True,
'old': False,
'right': True,
'right_path': 'f'}
]
}
assert ycm.to_dict(no_pairs=True) == expected
from jycm.helper import make_ignore_order_func
from jycm.jycm import YouchamaJsonDiffer
left = {
"ignore_order": [1, 2, 3],
"not_ignore_order": [1, 2, 3]
}
right = {
"ignore_order": [3, 2, 1],
"not_ignore_order": [3, 2, 1]
}
ycm = YouchamaJsonDiffer(left, right, ignore_order_func=make_ignore_order_func([
"^ignore_order$"
]))
diff_result = ycm.get_diff() # new API
expected = {
'list:add': [
{'left': '__NON_EXIST__',
'left_path': '',
'right': 2,
'right_path': 'not_ignore_order->[1]'},
{'left': '__NON_EXIST__',
'left_path': '',
'right': 1,
'right_path': 'not_ignore_order->[2]'}
],
'list:remove': [
{'left': 1,
'left_path': 'not_ignore_order->[0]',
'right': '__NON_EXIST__',
'right_path': ''},
{'left': 2,
'left_path': 'not_ignore_order->[1]',
'right': '__NON_EXIST__',
'right_path': ''}
]
}
# legacy usage:
# ycm.diff()
# diff_result = ycm.to_dict()
assert ycm.diff_result(no_pairs=True) == expected
from jycm.helper import make_ignore_order_func
from jycm.jycm import YouchamaJsonDiffer
left = {
"set_in_set": [
{
"id": 1,
"label": "label:1",
"set": [
1,
5,
3
]
},
{
"id": 2,
"label": "label:2",
"set": [
4,
5,
6
]
}
]
}
right = {
"set_in_set": [
{
"id": 2,
"label": "label:2",
"set": [
6,
5,
4
]
},
{
"id": 1,
"label": "label:1111",
"set": [
3,
2,
1
]
}
]
}
ycm = YouchamaJsonDiffer(left, right, ignore_order_func=make_ignore_order_func([
f"^set_in_set$",
f"^set_in_set->\\[\\d+\\]->set$"
]))
ycm.diff()
expected = {
'list:add': [
{'left': '__NON_EXIST__', 'right': 2, 'left_path': '', 'right_path': 'set_in_set->[1]->set->[1]'}
],
'list:remove': [
{'left': 5, 'right': '__NON_EXIST__', 'left_path': 'set_in_set->[0]->set->[1]', 'right_path': ''}
],
'value_changes': [
{'left': 'label:1', 'right': 'label:1111', 'left_path': 'set_in_set->[0]->label',
'right_path': 'set_in_set->[1]->label', 'old': 'label:1', 'new': 'label:1111'}
]
}
assert ycm.to_dict(no_pairs=True) == expected
import math
from jycm.operator import BaseOperator
class L2DistanceOperator(BaseOperator):
__operator_name__ = "operator:l2distance"
__event__ = "operator:l2distance"
def __init__(self, path_regex, distance_threshold):
super().__init__(path_regex=path_regex)
self.distance_threshold = distance_threshold
def diff(self, level: 'TreeLevel', instance, drill: bool) -> Tuple[bool, float]:
print("damn")
distance = math.sqrt(
(level.left["x"] - level.right["x"]) ** 2 + (level.left["y"] - level.right["y"]) ** 2
)
info = {
"distance": distance,
"distance_threshold": self.distance_threshold,
"pass": distance < self.distance_threshold
}
if not drill:
instance.report(self.__event__, level, info)
return True, 1 if info["pass"] else 0from jycm.jycm import YouchamaJsonDiffer
left = {
"distance_ok": {
"x": 1,
"y": 1
},
"distance_too_far": {
"x": 5,
"y": 5
},
}
right = {
"distance_ok": {
"x": 2,
"y": 2
},
"distance_too_far": {
"x": 7,
"y": 9
},
}
ycm = YouchamaJsonDiffer(left, right, custom_operators=[
L2DistanceOperator(f"distance.*", 3),
])
expected = {
'operator:l2distance': [
{'left': {'x': 1, 'y': 1}, 'right': {'x': 2, 'y': 2}, 'left_path': 'distance_ok',
'right_path': 'distance_ok', 'distance': 1.4142135623730951, 'distance_threshold': 3, 'pass': True},
{'left': {'x': 5, 'y': 5}, 'right': {'x': 7, 'y': 9}, 'left_path': 'distance_too_far',
'right_path': 'distance_too_far', 'distance': 4.47213595499958, 'distance_threshold': 3, 'pass': False}
]
}
assert {**ycm.to_dict(), "pairs": []} == expected
Since determining two things are equal or not is heavily depend on the context, it is not possible to build a json diff tool to meet all requirements.
JYCM choose another way: making it easy to compare values.
JYCM allows users just need to focus on defining the differing logic or what a distance is between two values and JYCM will take care all the other dirty works such as array-item-matching, ignoring-array-order, recursively comparing and calculating similarity.
By the way, JYCM uses algorithms below to match items in array:
| exactly matching | fuzzy matching | |
|---|---|---|
| with order | LCS | Edit distance |
| without order | Brute force | Kuhn–Munkres |
Speaking of flexibility, to make a new operator, you just to need to extend a class called BaseOperator with such function signature:
diff: (level: 'TreeLevel', instance, drill: bool) => [float, boolean]
where the first return is a float number between zero and one for describing how similar level.left and level.right are and the second return is used to indicate whether comparing process should stop here.
pip install -r requirements-dev.txtgit checkout master && git pull
bumpversion {patch|minor|major}
git push && git push --tagsmake testcov make docs
