Creating a directory structure from JSON

Question

I have a JSON file:

{
'Document':[
[{'fields': {'name': 'js/main.js', 'content': 'hello'}, 'pk': 284, 'model': 'Document'}],
[{'fields': {'name': 'css/main.css', 'content': '2'}, 'pk': 287, 'model': 'Document'}],
[{'fields': {'name': 'about_us.html', 'content': 'again hello'}, 'pk': 306, 'model': 'Document'}]],
'Package':
[{'fields': {'package_type': 'THEME', 'base_package': None, 'created_date': '2015-05-25T15:39:16.781Z', 'name': '25_may', 'rating_avg': 0.0, 'user': 2, 'rating_count': 0, 'is_published': True}, 'pk': 129, 'model': 'Package'}]
}

I want to generate directory structure based on JSON data:

25_may
|- css
| |- main.css
|- js
| |-main.js 
|- about_us.html

Code to achieve above:

def my_func():
 package_name = response['Package'][0]['fields']['name']
 for doc in response['Document']: 
 filename = os.path.join(package_name, doc[0]['fields']['name'])
 content = doc[0]['fields']['content']
 if not os.path.exists(os.path.dirname(filename)):
 os.makedirs(os.path.dirname(filename))
 with open(filename, "w") as f:
 f.write(content) 

Is there an efficient and better way to do this?

Answer 1

It seems fine, but I suggest to improve some minor improvements:

• filename is not a simple file name but has directory element too, so I'd call it path
• Instead of calling os.path.dirname twice, I'd call it once and cache the result in a local variable

Like this:

package_name = response['Package'][0]['fields']['name']
for doc in response['Document']: 
 path = os.path.join(package_name, doc[0]['fields']['name'])
 basedir = os.path.dirname(filename)
 if not os.path.exists(basedir):
 os.makedirs(basedir)
 content = doc[0]['fields']['content']
 with open(filename, "w") as f:
 f.write(content) 

Btw, the JSON structure looks a bit odd, with several arrays with a single element. Makes me wonder why these arrays are there at all, instead of their contained objects directly.

I'd also be concerned about format changes in the JSON: your code is tightly coupled to an unintuitive structure, and if anything changes later, it might be difficult to migrate the implementation.

• Prashant Gaur: Thanks for your suggestion for json structure. I will change it's format.