Include or exclude JSON data if the value is empty WITHOUT using multiple If statements-CodePudding

I have this JSON to send via python requests. There are about 200 separate items. I want to set each item in the JSON to a variable and if the variable is empty I want to exclude the item from the list. How can I do this efficiently? I could put a ton of IF statements in, but I don't think that's very efficient.

#The variables:
_var1 = 123
_var2 = 40
_var3 = ""
_var4 = 5

#The JSON:
"""
{
  "id": _var1,
  "weight": _var2,
  "width": _var3,
  "depth": _var4
  }
"""

#My desired result:
"""
{
  "id": _var1,
  "weight": _var2,
  "depth": _var4
  }
"""

I assume I could could use multiple if/else statements. and then concatenate all of the strings.

if len(_var1)>0:
    print(str(_var11))
else: print("")
if len(_var2)>0:
    print(str(_var2))
else: print("")

I'm also assuming someone has a better way. I don't really want to write 200 if/else statements.

CodePudding user response：

You need a single if clause to check if it's empty

import json
keys = ["id", "weight", "width", "depth"]
vals = [_var1, _var2, _var3, _var4]

# check if a var is empty
d = {k:v for k,v in zip(keys, vals) if v}
j = json.dumps(d, indent=2)
print(j)


# {
#   "id": 123,
#   "weight": 40,
#   "depth": 5
# }

CodePudding user response：

Use a dictionary comprehension to loop through the dictionary, and create a new dictionary that only has the non-empty elements.

And use the json module to convert to/from JSON.

import json

old_dict = json.loads(old_json)
new_dict = {key: value for key, value in old_dict.items() if len(str(value)) > 0}
new_json = json.dumps(new_dict)