konsti
5cef40d87a
I intend this to become the main form of caching for puffin: You can make http requests, you tranform the data to what you really need, you have control over the cache key, and the cache is always json (or anything else much faster we want to replace it with as long as it's serde!)
23 lines
620 B
Rust
23 lines
620 B
Rust
use std::hash::Hasher;
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use crate::cache_key::{CacheKey, CacheKeyHasher};
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/// Compute a hex string hash of a `CacheKey` object.
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///
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/// The value returned by [`digest`] should be stable across releases and platforms.
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pub fn digest<H: CacheKey>(hashable: &H) -> String {
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to_hex(cache_key_u64(hashable))
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}
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/// Convert a u64 to a hex string.
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fn to_hex(num: u64) -> String {
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hex::encode(num.to_le_bytes())
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}
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/// Compute a u64 hash of a [`CacheKey`] object.
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fn cache_key_u64<H: CacheKey>(hashable: &H) -> u64 {
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let mut hasher = CacheKeyHasher::new();
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hashable.cache_key(&mut hasher);
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hasher.finish()
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}
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