I have been working on a project that involves parsing a CSV file in order to turn all the data into a very specifically formatted JSON following a complex schema. I have to custom make this program as the required complexity of the JSON makes existing converters fail. I am mostly there, I have run into one final roadblock though:
I have nested dictionaries, and occasionally there must be a list within those, this list will contain further dictionaries. This is fine, I have been able to complete that, BUT now I need to find a way to add more nested dictionaries within those. Below is a simplified breakdown of the concept.
the CSV will look something like this, where the @ before a tag indicates it's a list
x.a, x.b.z, x.b.y, [email protected], [email protected], [email protected], x.d, x.e.z, x.e.y
ab, cd, ef, gh, ij, kl, mn, op, qr
this should result in the following JSON
{
"x": {
"a": "ab",
"b": {
"z": "cd",
"y": "ef"
},
"c": [
{
"z": {
"nest1": "gh",
"nest2": "ij"
}
},
{
"yy": "kl"
}
],
"d": "mn",
"e": {
"z": "op",
"y": "qr"
}
}
}
This is one issue that I haven't been able to solve, my current code can only do one dictionary after the list item, not further. I also need to be able to somehow do the following within a list of dictionaries:
"c": [
{
"z": {
"nest1": "gh"
},
"zz": {
"nest2": "ij"
}
},
{
"yy": "kl"
}
i.e. somehow add multiple nested dictionaries within the dictionary in the list. The problem with this occurs within the fact that these aren't reference-able by name, so I do not know how I could potentially indicate to do that within the CSV format.
Here is the code I have that works up to the first dictionary nested within a list:
import json
import pandas as pd
from os.path import exists
# df1 = pd.read_csv("excelTestFacilities.csv", header = 1, sep=",", keep_default_na=False, engine="python")
# df2 = pd.read_csv("excelTestFacilityContacts.csv", header = 1, sep=",", keep_default_na=False, engine="python")
# df = pd.merge(df1, df2, how = 'inner')
df = pd.read_csv("csvTestFile.csv", header = 1, sep=", ", keep_default_na=False, engine="python")
#print(df) # uncomment to see the transformation
json_data = df.to_dict(orient="records")
#print(json_data)
def unflatten_dic(dic):
"""
Unflattens a CSV list into a set of nested dictionaries
"""
ini = {}
for k,v in list(dic.items()):
node = ini
list_bool = False
*parents, key = k.split('.')
for parent in parents:
if parent[0] == '@':
list_bool = True
if list_bool:
for parent in parents:
if parent[0] == '@':
node[parent[1:]] = node = node.get(parent[1:], [])
else:
node[parent] = node = node.get(parent, {})
node.append({key : v})
else:
for parent in parents:
node[parent] = node = node.get(parent, {})
node[key] = v
return ini
def merge_lists(dic):
"""
Removes duplicates within sets
"""
for k,v in list(dic.items()):
if isinstance(v, dict):
keys = list(v.keys())
vals = list(v.values())
if all(isinstance(l, list) and len(l)==len(vals[0]) for l in vals):
dic[k] = []
val_tuple = set(zip(*vals)) # removing duplicates with set()
for t in val_tuple:
dic[k].append({subkey: t[i] for i, subkey in enumerate(keys)})
else:
merge_lists(v)
elif isinstance(v, list):
dic[k] = list(set(v)) # removing list duplicates
def clean_blanks(value):
"""
Recursively remove all None values from dictionaries and lists, and returns
the result as a new dictionary or list.
"""
if isinstance(value, list):
return [clean_blanks(x) for x in value if x != ""]
elif isinstance(value, dict):
return {
key: clean_blanks(val)
for key, val in value.items()
if val != "" and val != {}
}
else:
return value
def add_to_dict(section_added_to, section_to_add, value, reportNum):
"""
Adds a value to a given spot within a dictionary set.
section_added_to is optional for adding the set to a deeper section such as facility
section_to_add is the name that the new dictionary entry will have
value is the item to be added
reportNum is the number indicating which report to add to, starting at 0
"""
if section_added_to != '':
end_list[reportNum][section_added_to][section_to_add] = value
else:
end_list[reportNum][section_to_add] = value
def read_add_vals(filename_prefix, added_to, section):
for i in range(len(end_list)):
temp_list = []
filename = filename_prefix str(i 1) ".csv"
if not exists(filename):
continue;
temp_df = pd.read_csv(filename, header = 1, sep=",", keep_default_na=False, engine="python")
temp_json = temp_df.to_dict(orient="records")
for y in temp_json:
return_ini = unflatten_dic(y)
temp_list.append(return_ini)
add_to_dict(added_to, section, temp_list, i)
global end_list
end_list = []
for x in json_data:
return_ini = unflatten_dic(x)
end_list.append(return_ini)
#read_add_vals('excelTestPermitsFac', 'facility', 'permits');
json_data = clean_blanks(end_list)
final_json = {"year":2021, "version":"2022-02-14", "reports":json_data}
print(json.dumps(final_json, indent=4))
There is some parts of this code that are involved in other components of the overall end JSON, but I am mainly concerned with how to change unflatten_dic() Here is my current working code for changing unflatten_dic(), even though it doesn't work...
def list_get(list, list_item):
i = 0
for dict in list:
if list_item in dict:
return dict.get(list_item, {})
i = 1
return {}
def check_in_list(list, list_item):
i = 0
for dict in list:
if list_item in dict:
return i
i = 1
return -1
def unflatten_dic(dic):
"""
Unflattens a CSV list into a set of nested dictionaries
"""
ini = {}
for k,v in list(dic.items()):
node = ini
list_bool = False
*parents, key = k.split('.')
for parent in parents:
if parent[0] == '@':
list_bool = True
previous_node_list = False
if list_bool:
for parent in parents:
print(parent)
if parent[0] == '@':
node[parent[1:]] = node = node.get(parent[1:], [])
ends_with_dict = False
previous_node_list = True
else:
print("else")
if previous_node_list:
print("prev list")
i = check_in_list(node, parent)
if i >= 0:
node[i] = node = list_get(node, parent)
else:
node.append({parent : {}})
previous_node_list = False
ends_with_dict = True
else:
print("not prev list")
node[parent] = node = node.get(parent, {})
previous_node_list = False
if ends_with_dict:
node[key] = v
else:
node.append({key : v})
else:
for parent in parents:
node[parent] = node = node.get(parent, {})
node[key] = v
#print(node)
return ini
Any, even small, amount of help would be greatly appreciated.
CodePudding user response：
It is easiest to use recursion and collections.defaultdict to group child entries on their parents (each entry is separated by the . in the csv data):
from collections import defaultdict
def to_dict(vals, is_list = 0):
def form_child(a, b):
return b[0][0] if len(b[0]) == 1 else to_dict(b, a[0] == '@')
d = defaultdict(list)
for a, *b in vals:
d[a].append(b)
if not is_list:
return {a[a[0] == '@':]:form_child(a, b) for a, b in d.items()}
return [{a[a[0] == '@':]:form_child(a, b)} for a, b in d.items()]
import csv, json
with open('filename.csv') as f:
data = list(csv.reader(f))
r = [a.split('.') [b] for i in range(0, len(data), 2) for a, b in zip(data[i], data[i 1])]
print(json.dumps(to_dict(r), indent=4))
Output:
{
"x": {
"a": "ab",
"b": {
"z": "cd",
"y": "ef"
},
"c": [
{
"z": {
"nest1": "gh",
"nest2": "ij"
}
},
{
"yy": "kl"
}
],
"d": "mn",
"e": {
"z": "op",
"y": "qr"
}
}
}
CodePudding user response：
I managed to get it working in what seems to be all scenarios. Here is the code that I made for the unflatten_dic() function.
def unflatten_dic(dic):
"""
Unflattens a CSV list into a set of nested dictionaries
"""
ini = {}
for k,v in list(dic.items()):
node = ini
list_bool = False
*parents, key = k.split('.')
# print("parents")
# print(parents)
for parent in parents:
if parent[0] == '@':
list_bool = True
if list_bool:
for parent in parents:
if parent[0] == '@':
node[parent[1:]] = node = node.get(parent[1:], [])
elif parent.isnumeric():
# print("numeric parent")
# print("length of node")
# print(len(node))
if len(node) > int(parent):
# print("node length good")
node = node[int(parent)]
else:
node.append({})
node = node[int(parent)]
else:
node[parent] = node = node.get(parent, {})
try:
node.append({key : v})
except AttributeError:
node[key] = v
else:
for parent in parents:
node[parent] = node = node.get(parent, {})
node[key] = v
return ini
I haven't run into an issue thus far, this is based on the following rules for the CSV:
@ before any name results in that item being a list
if the section immediately after a list in the CSV is a number, that will create multiple dictionaries within the list. Here is an example
x.a, x.b.z, x.b.y, [email protected], [email protected], [email protected], x.d, x.e.z, x.e.y, [email protected], [email protected][email protected], [email protected][email protected]
ab, cd, ef, gh, , kl, mn, op, qr, st, uv, wx
12, 34, 56, 78, 90, 09, , 65, 43, 21, , 92
This will result in the following JSON after formatting
"reports": [
{
"x": {
"a": "ab",
"b": {
"z": "cd",
"y": "ef"
},
"c": [
{
"zz": "gh"
},
{
"yy": {
"l": "st",
"m": [
{
"q": "uv"
},
{
"r": "wx"
}
]
}
},
{
"zz": "kl"
}
],
"d": "mn",
"e": {
"z": "op",
"y": "qr"
}
}
},
{
"x": {
"a": "12",
"b": {
"z": "34",
"y": "56"
},
"c": [
{
"zz": "78"
},
{
"zz": "90",
"yy": {
"l": "21",
"m": [
{
"r": "92"
}
]
}
},
{
"zz": "09"
}
],
"e": {
"z": "65",
"y": "43"
}
}
}
]