JSONConfig has no delete method

meme · 02-24-2011, 03:38 AM

JSONConfig in utils/config.py allows set/get but not delete of a specific key. Is it possible to delete a key from a plugin's json file?

Normally I don't need this, but I'm renaming a key and the only way I found to 'remove' the old key is to set the old key value to Null.

This is sufficient, although it leaves old/unused data in the file, and it means an extra test is needed since the key exists but the data is Null (since get(store_name, DEFAULTS) will not set the key to DEFAULTS if the key exists but is a dict with Null).

chaley · 02-24-2011, 06:21 AM

JSONConfig inherits from XMLConfig, which does have a delete operation. Have you tried using "del json_object[key]"?

meme · 02-24-2011, 08:38 AM

That was it, thanks. I've used the del statement elsewhere, and noticed that XMLConfig inherits from dict, but didn't connect using del on it would work like del for a dict. The del statement is a bit odd anyway since most everything else is called like a function - I was looking for a del() method and all I could see was __delitem__ (which given the __ I believe is an internal method).

02-24-2011, 03:38 AM	#1
meme Sigil developer Posts: 1,275 Karma: 1101600 Join Date: Jan 2011 Location: UK Device: Kindle PW, K4 NT, K3, Kobo Touch	JSONConfig has no delete method JSONConfig in utils/config.py allows set/get but not delete of a specific key. Is it possible to delete a key from a plugin's json file? Normally I don't need this, but I'm renaming a key and the only way I found to 'remove' the old key is to set the old key value to Null. This is sufficient, although it leaves old/unused data in the file, and it means an extra test is needed since the key exists but the data is Null (since get(store_name, DEFAULTS) will not set the key to DEFAULTS if the key exists but is a dict with Null).

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02-24-2011, 06:21 AM	#2
chaley Grand Sorcerer Posts: 11,742 Karma: 6997045 Join Date: Jan 2010 Location: Notts, England Device: Kobo Libra 2	JSONConfig inherits from XMLConfig, which does have a delete operation. Have you tried using "del json_object[key]"?

02-24-2011, 08:38 AM	#3
meme Sigil developer Posts: 1,275 Karma: 1101600 Join Date: Jan 2011 Location: UK Device: Kindle PW, K4 NT, K3, Kobo Touch	That was it, thanks. I've used the del statement elsewhere, and noticed that XMLConfig inherits from dict, but didn't connect using del on it would work like del for a dict. The del statement is a bit odd anyway since most everything else is called like a function - I was looking for a del() method and all I could see was __delitem__ (which given the __ I believe is an internal method).