How to convert a nested hash which is in string back into a hash?

Question

I stored my nested hash in a file, and while retrieving it, I want to it back in a hash form instead of string. When I read a file it will give me a string and then how can I parse it back to a hash. This is the string hash in the file:

{"SONGS"=>{1=>["2018-05-29 18:19:14 +0530", "HAPPY", "Meri Sapnon Ki Rani"]}}

Data was in hash and I wrote it to file. After reading it from the same file, how can I parse back to hash — Salman Shaik, May 30 '18 at 04:39

iGian · Accepted Answer · 2018-05-30T07:14:37.330

0

Already in SO.

WARNING SECURITY RISK!

For your string you need to pass to eval, but this is a SECURITY RISK

string = '{"SONGS"=>{1=>["2018-05-29 18:19:14 +0530", "HAPPY", "Meri Sapnon Ki Rani"]}}'
p eval(string).class

If you need to store data structures in files, I suggest you to take a look at YAML module. Look at this post, for example.

As suggested in comments:

Consider also security concerns, look this post.
Consider to change a little bit the string syntax to use a JSON structure. See below.

Use of JSON:

require 'json'
json_string = '{"songs":{"1":{"date": "2018-05-29 18:19:14 +0530", "title":"HAPPY", "name":"Meri Sapnon Ki Rani"}}}'
p JSON::parse(json_string).class

edited May 30 '18 at 07:14

answered May 30 '18 at 04:44

iGian

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only if you don't have any security concerns, which is never the case I assume – Subash May 30 '18 at 04:48
1

Always prefer `JSON#parse` over `eval`. – Aleksei Matiushkin May 30 '18 at 04:52
@Subash, good point I edited. Thanks. – iGian May 30 '18 at 05:13
@mudasobwa, thanks for the suggestion, I added the point, changing the string to be compliant with the format. – iGian May 30 '18 at 05:16
Never use "eval", it should not even be there in the answer as first option. "eval" is a security risk! – Pascal May 30 '18 at 06:05
@pascalbetz, picked up your warning. I added an alert for security risk. But I replied to the question and to the string as provided JSON::parse doesn't apply. – iGian May 30 '18 at 07:17

How to convert a nested hash which is in string back into a hash?

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