Archive for the ‘Web Development’ tag
URL-Safe Timestamps using Base64
Passing around timestamps in URLs is a common task. We usually want our URLs to be as shortest as possible. I’ve found using Base64 to result in the shortest URL-safe representation, just 6 chars. This compares with the 12 chars of the naive way, and 8 chars when using hex representation.
The following Python functions allow you to build and read these 6 chars URL-safe timestamps:
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“CC Yourself” and Spam
Every good web programmer will note that the following contact form markup is probably flawed
<form>
...
<input type="hidden" name="to" value="support@example.com" />
...
</form>as it is likely that if the value of the “to” field changes the message will be sent to the modified address. The problem with this kind of functionality is that it allows a malicious user to send emails from your mail server. More specifically, it can allow spammers to user your benign server t send their spam (and as a side effect you might be flagged as a spammer yourself).
As this case is pretty obvious one doesn’t see many real-life uses of it anymore (but careless programmers used it more often n the past until they learned better). However one can achieve similar goals (spam-wise) by utilizing a common feature in contact forms: the “CC yourself” checkbox.
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