5 ms·
Escaping isn't always a yes/no question. If someone enters "foo bar" into your frontend, should the backend only see "foo%20bar" ?
by mrkeen 4y ago
Escaping isn't always a yes/no question.
If someone enters "foo bar" into your frontend, should the backend only see "foo%20bar" ?
- pavlov 4y agoThe back-end should see a 7-byte buffer with values [102 111 111 032 098 097 114], assume it's UTF-8 and convert that to its internal string representation?
- ezfe 4y agono, the backend has no reason to see `foo%20bar` - you escape when you're combining that string with other strings (ie into HTML, into a SQL query, etc.)
- evilDagmar 4y agoThere's just a whole library of CVEs for people who attempt to escape things being sent to SQL. Use parameterized queries already.
- 8n4vidtmkvmk 4y agoevery one says "just use parameterized queries" but they don't handle arrays which makes the idea rather useless.
- jiggawatts 4y agoMany database engines can handle arrays, or table-valued variables which are basically the same thing. Most ORMs will also abstract away arrays for you, so you as the developer never need to deal with escaping of data in arrays.
- 8n4vidtmkvmk 4y agoWhich relational DB supports this natively? ORMs don't count. They're just editing the SQL.
- orf 4y agoUse one that does? Or build it yourself? ARRAY[?, ?, ?, ?]
- 8n4vidtmkvmk 4y agoI do, but I feel like it defeats the purpose. In order to insert those ?s you have to parse the query, which is exactly what we're trying to avoid.
- orf 4y agoSorry, I’m not clear on why you need to parse the query? Imagine you want to INSERT (int, array[], int) into a table. Why can’t you just generate the following SQL? INSERT INTO foo VALUES (?, ARRAY[?,?,?], ?) Where param 1-3 are indexes 0-2 in the array? This is basically what everything else does when handing arrays, or other composite types like coordinates. If the language or libraries are not suitable for doing this then the language or libraries are the problem, not the approach.
- 8n4vidtmkvmk 4y agoIf you're using an ORM/SQL builder, sure. If you prefer writing raw SQL because ORMs are often quite limiting, then you have to write something like `INSERT INTO foo VALUES ?` and then you pass it `[1, [2,3,4], 5]` as params, which is mostly fine but you still have to parse out that "?" from the query. Why parse? Because what if you wrote 'VALUES "?"' now it's a string and shouldn't be replaced. It would be much nicer if you could just send the query to the SQL server and figure out what to do with the params.
- orf 4y agoI think your argument is “if I try hard enough to make what I want to do really hard, it will be really hard”. I agree. I’m not sure I buy your argument about ORMs being limiting, given your current… limitations. Of course you could just do CAST(? AS …) or use something like “string_to_array(?)”. But that’s just working around not being able to compose queries.