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Key character set

2 replies [Last post]
Tue, 03/19/2013 - 12:30
fischer70
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Joined: 03/19/2013
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We've bumped against the key size limit (250 "characters") and are compressing the keys as they go in to get them to fit. I seem to be able to pass in 250 length strings from the Java client (which from Java's point of view is 500 bytes, as they are 2-byte UTF characters). I'm guessing this get's transmuted to a 250 char string in the client side libraries somewhere? If so, what's the character set so I can ensure my ugly compressed strings are all represented?

Thanks!

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Fri, 03/22/2013 - 04:52
daschl
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Joined: 05/19/2012
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Hi,

so normally, Couchbase can store anything that is UTF-8 encoded and is not longer than around 250 characters. Do you have problems with storing 250 utf-8 characters through the SDK?

Let me know and if you have some problems just post a concrete example and we'll walk it through from there.

Thanks!

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Fri, 03/22/2013 - 05:09
fischer70
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Joined: 03/19/2013
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Hi,

Thanks for the reply. The 250 character limit does mess us up, but I believe I was able to track down the function that the Java client uses to validate the key so I can act accordingly. If I did find the correct block of code, then it's a byte count, which means you have to be careful with UTF-8, as many characters will need two bytes and key.length() doesn't necessarily tell you what you need. For posterity, I copied the function below in case anyone else wonders.

public  void validateKey(String key) throws Exception {
	byte[] keyBytes = key.getBytes("UTF-8");
	if (keyBytes.length > 250) {
		System.err.println(key + " is " + key.length() + " characters, but " + keyBytes.length+ " bytes.");
		throw new IllegalArgumentException("Key is too long (maxlen = " + 250 + ")");
	}
	if (keyBytes.length == 0) {
		throw new IllegalArgumentException("Key must contain at least one character.");
	}
	for (byte b : keyBytes) {
		if (b == ' ' || b == '\n' || b == '\r' || b == 0) {
			throw new IllegalArgumentException("Key contains invalid characters:  ``" + key + "''");
		}
	}
}

Best,
Nate

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