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Python’s new t-strings

(davepeck.org)
620 points tambourine_man | 1 comments | 21 Apr 25 04:31 UTC | HN request time: 0s | source
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TekMol ◴[21 Apr 25 08:37 UTC] No.43749608[source]▶
Will this allow neat SQL syntax like the following?

    city = 'London'
    min_age = 21
    # Find all users in London who are 21 or older:
    users = db.get(t'
        SELECT * FROM users
        WHERE city={city} AND age>{min_age}
    ')
If the db.get() function accepts a template, it should, right?

This would be the nicest way to use SQL I have seen yet.

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jbaiter ◴[21 Apr 25 08:47 UTC] No.43749674[source]▶
Thanks, I hate it. While it's nice syntactic sugar, the difference between an SQL injection vulnerability and a properly parametrized query is now a single letter that's easily missed
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JimDabell ◴[21 Apr 25 09:07 UTC] No.43749804[source]▶
The t-string produces a Template object without a __str__() method. You can’t mistakenly use an f-string in its place. Either the code expects a string, in which case passing it a Template would blow it up, or the code expects a Template, in which case passing it a string would blow it up.
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b3orn ◴[21 Apr 25 10:03 UTC] No.43750148[source]▶
If it's not a completely new library written exclusively around templates, such code currently accepts strings and will most likely continue to accept strings for backwards compatibility.
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1. keybored ◴[23 Apr 25 14:48 UTC] No.43772850[source]▶
In that case I don’t understand the security regression that t-strings cause (see GP). Before it was all just strings, but you had to make sure to use them in the correct place. Now you can still just use strings for backwards compat. but you can also move on to a distinctly-typed solution for SQL and the like.