Redis cjson: Is there a way to manipulate JSON without decoding it completely?

Question

Given the below example, is there a way to change the value from "bar" to "blah" without decoding them?

redis 127.0.0.1:6379> eval 'return cjson.encode({["foo"]= "bar"})' 0
"{\"foo\":\"bar\"}"

redis 127.0.0.1:6379> eval 'return cjson.decode(ARGV[1])["foo"]' 0 "{\"foo\":\"bar\"}"
"bar"

Reference for example: https://redis.io/commands/eval

@for_stack Cannot change, as Redis comes with cjson. And I cannot load another module. — rohitmohta, May 15 '18 at 20:37

score 10 · Accepted Answer · answered May 15 '18 at 13:29

Nope, you'll have to go through a full decoding and encoding cycle. That's exactly one of the "pains" that http://rejson.io tries to solve. See http://rejson.io/performance/#comparison-vs-server-side-lua-scripting for more info.

Disclaimer: author of ReJSON here.

Redis cjson: Is there a way to manipulate JSON without decoding it completely?

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