Change IdentifierAccess to VariantAccess

src/repo.rs

@@ -74,7 +74,7 @@ pub(crate) trait FullRepo:
     + HashRepo
     + MigrationRepo
     + AliasAccessRepo
-    + IdentifierAccessRepo
+    + VariantAccessRepo
     + Send
     + Sync
     + Clone
@@ -183,41 +183,39 @@ where
 }
 
 #[async_trait::async_trait(?Send)]
-pub(crate) trait IdentifierAccessRepo: BaseRepo {
-    type IdentifierAccessStream<I>: Stream<Item = Result<I, StoreError>>
-    where
-        I: Identifier;
+pub(crate) trait VariantAccessRepo: BaseRepo {
+    type VariantAccessStream: Stream<Item = Result<(Self::Bytes, String), RepoError>>;
 
-    async fn accessed<I: Identifier>(&self, identifier: I) -> Result<(), StoreError>;
+    async fn accessed(&self, hash: Self::Bytes, variant: String) -> Result<(), RepoError>;
 
-    async fn older_identifiers<I: Identifier>(
+    async fn older_variants(
         &self,
         timestamp: time::OffsetDateTime,
-    ) -> Result<Self::IdentifierAccessStream<I>, RepoError>;
+    ) -> Result<Self::VariantAccessStream, RepoError>;
 
-    async fn remove<I: Identifier>(&self, identifier: I) -> Result<(), StoreError>;
+    async fn remove(&self, hash: Self::Bytes, variant: String) -> Result<(), RepoError>;
 }
 
 #[async_trait::async_trait(?Send)]
-impl<T> IdentifierAccessRepo for actix_web::web::Data<T>
+impl<T> VariantAccessRepo for actix_web::web::Data<T>
 where
-    T: IdentifierAccessRepo,
+    T: VariantAccessRepo,
 {
-    type IdentifierAccessStream<I> = T::IdentifierAccessStream<I> where I: Identifier;
+    type VariantAccessStream = T::VariantAccessStream;
 
-    async fn accessed<I: Identifier>(&self, identifier: I) -> Result<(), StoreError> {
-        T::accessed(self, identifier).await
+    async fn accessed(&self, hash: Self::Bytes, variant: String) -> Result<(), RepoError> {
+        T::accessed(self, hash, variant).await
     }
 
-    async fn older_identifiers<I: Identifier>(
+    async fn older_variants(
         &self,
         timestamp: time::OffsetDateTime,
-    ) -> Result<Self::IdentifierAccessStream<I>, RepoError> {
-        T::older_identifiers(self, timestamp).await
+    ) -> Result<Self::VariantAccessStream, RepoError> {
+        T::older_variants(self, timestamp).await
     }
 
-    async fn remove<I: Identifier>(&self, identifier: I) -> Result<(), StoreError> {
-        T::remove(self, identifier).await
+    async fn remove(&self, hash: Self::Bytes, variant: String) -> Result<(), RepoError> {
+        T::remove(self, hash, variant).await
     }
 }
 

src/repo/sled.rs

@@ -13,7 +13,6 @@ use futures_util::{Future, Stream};
 use sled::{CompareAndSwapError, Db, IVec, Tree};
 use std::{
     collections::HashMap,
-    marker::PhantomData,
     path::PathBuf,
     pin::Pin,
     sync::{
@@ -23,7 +22,7 @@ use std::{
 };
 use tokio::{sync::Notify, task::JoinHandle};
 
-use super::{AliasAccessRepo, IdentifierAccessRepo, RepoError};
+use super::{AliasAccessRepo, RepoError, VariantAccessRepo};
 
 macro_rules! b {
     ($self:ident.$ident:ident, $expr:expr) => {{
@@ -51,6 +50,9 @@ pub(crate) enum SledError {
     #[error("Error formatting timestamp")]
     Format(#[source] time::error::Format),
 
+    #[error("Error parsing variant key")]
+    VariantKey(#[from] VariantKeyError),
+
     #[error("Operation panicked")]
     Panic,
 }
@@ -72,8 +74,8 @@ pub(crate) struct SledRepo {
     queue: Tree,
     alias_access: Tree,
     inverse_alias_access: Tree,
-    identifier_access: Tree,
-    inverse_identifier_access: Tree,
+    variant_access: Tree,
+    inverse_variant_access: Tree,
     in_progress_queue: Tree,
     queue_notifier: Arc<RwLock<HashMap<&'static str, Arc<Notify>>>>,
     uploads: Tree,
@@ -108,8 +110,8 @@ impl SledRepo {
             queue: db.open_tree("pict-rs-queue-tree")?,
             alias_access: db.open_tree("pict-rs-alias-access-tree")?,
             inverse_alias_access: db.open_tree("pict-rs-inverse-alias-access-tree")?,
-            identifier_access: db.open_tree("pict-rs-identifier-access-tree")?,
-            inverse_identifier_access: db.open_tree("pict-rs-inverse-identifier-access-tree")?,
+            variant_access: db.open_tree("pict-rs-variant-access-tree")?,
+            inverse_variant_access: db.open_tree("pict-rs-inverse-variant-access-tree")?,
             in_progress_queue: db.open_tree("pict-rs-in-progress-queue-tree")?,
             queue_notifier: Arc::new(RwLock::new(HashMap::new())),
             uploads: db.open_tree("pict-rs-uploads-tree")?,
@@ -169,7 +171,7 @@ impl FullRepo for SledRepo {
     }
 }
 
-type IterValue = Option<(sled::Iter, Result<sled::IVec, RepoError>)>;
+type IterValue = Option<(sled::Iter, Result<IVec, RepoError>)>;
 
 pub(crate) struct IterStream {
     iter: Option<sled::Iter>,
@@ -177,7 +179,7 @@ pub(crate) struct IterStream {
 }
 
 impl futures_util::Stream for IterStream {
-    type Item = Result<sled::IVec, RepoError>;
+    type Item = Result<IVec, RepoError>;
 
     fn poll_next(
         mut self: Pin<&mut Self>,
@@ -219,9 +221,8 @@ pub(crate) struct AliasAccessStream {
     iter: IterStream,
 }
 
-pub(crate) struct IdentifierAccessStream<I> {
+pub(crate) struct VariantAccessStream {
     iter: IterStream,
-    identifier: PhantomData<fn() -> I>,
 }
 
 impl futures_util::Stream for AliasAccessStream {
@@ -245,19 +246,20 @@ impl futures_util::Stream for AliasAccessStream {
     }
 }
 
-impl<I> futures_util::Stream for IdentifierAccessStream<I>
-where
-    I: Identifier,
-{
-    type Item = Result<I, StoreError>;
+impl futures_util::Stream for VariantAccessStream {
+    type Item = Result<(IVec, String), RepoError>;
 
     fn poll_next(
         mut self: Pin<&mut Self>,
         cx: &mut std::task::Context<'_>,
     ) -> std::task::Poll<Option<Self::Item>> {
         match std::task::ready!(Pin::new(&mut self.iter).poll_next(cx)) {
-            Some(Ok(bytes)) => std::task::Poll::Ready(Some(I::from_bytes(bytes.to_vec()))),
-            Some(Err(e)) => std::task::Poll::Ready(Some(Err(e.into()))),
+            Some(Ok(bytes)) => std::task::Poll::Ready(Some(
+                parse_variant_access_key(bytes)
+                    .map_err(SledError::from)
+                    .map_err(RepoError::from),
+            )),
+            Some(Err(e)) => std::task::Poll::Ready(Some(Err(e))),
             None => std::task::Poll::Ready(None),
         }
     }
@@ -327,75 +329,69 @@ impl AliasAccessRepo for SledRepo {
 }
 
 #[async_trait::async_trait(?Send)]
-impl IdentifierAccessRepo for SledRepo {
-    type IdentifierAccessStream<I> = IdentifierAccessStream<I> where I: Identifier;
+impl VariantAccessRepo for SledRepo {
+    type VariantAccessStream = VariantAccessStream;
+
+    async fn accessed(&self, hash: Self::Bytes, variant: String) -> Result<(), RepoError> {
+        let key = variant_access_key(&hash, &variant);
 
-    async fn accessed<I: Identifier>(&self, identifier: I) -> Result<(), StoreError> {
         let now_string = time::OffsetDateTime::now_utc()
             .format(&time::format_description::well_known::Rfc3339)
-            .map_err(SledError::Format)
-            .map_err(RepoError::from)?;
+            .map_err(SledError::Format)?;
 
-        let identifier_access = self.identifier_access.clone();
-        let inverse_identifier_access = self.inverse_identifier_access.clone();
-
-        let identifier = identifier.to_bytes()?;
+        let variant_access = self.variant_access.clone();
+        let inverse_variant_access = self.inverse_variant_access.clone();
 
         actix_rt::task::spawn_blocking(move || {
-            if let Some(old) =
-                identifier_access.insert(identifier.clone(), now_string.as_bytes())?
-            {
-                inverse_identifier_access.remove(old)?;
+            if let Some(old) = variant_access.insert(&key, now_string.as_bytes())? {
+                inverse_variant_access.remove(old)?;
             }
-            inverse_identifier_access.insert(now_string, identifier)?;
+            inverse_variant_access.insert(now_string, key)?;
             Ok(()) as Result<(), SledError>
         })
         .await
         .map_err(|_| RepoError::Canceled)?
         .map_err(RepoError::from)
-        .map_err(StoreError::from)
     }
 
-    async fn older_identifiers<I: Identifier>(
+    async fn older_variants(
         &self,
         timestamp: time::OffsetDateTime,
-    ) -> Result<Self::IdentifierAccessStream<I>, RepoError> {
+    ) -> Result<Self::VariantAccessStream, RepoError> {
         let time_string = timestamp
             .format(&time::format_description::well_known::Rfc3339)
             .map_err(SledError::Format)?;
 
-        let inverse_identifier_access = self.inverse_identifier_access.clone();
+        let inverse_variant_access = self.inverse_variant_access.clone();
 
         let iter =
-            actix_rt::task::spawn_blocking(move || inverse_identifier_access.range(..=time_string))
+            actix_rt::task::spawn_blocking(move || inverse_variant_access.range(..=time_string))
                 .await
                 .map_err(|_| RepoError::Canceled)?;
 
-        Ok(IdentifierAccessStream {
+        Ok(VariantAccessStream {
             iter: IterStream {
                 iter: Some(iter),
                 next: None,
             },
-            identifier: PhantomData,
         })
     }
 
-    async fn remove<I: Identifier>(&self, identifier: I) -> Result<(), StoreError> {
-        let identifier_access = self.identifier_access.clone();
-        let inverse_identifier_access = self.inverse_identifier_access.clone();
+    async fn remove(&self, hash: Self::Bytes, variant: String) -> Result<(), RepoError> {
+        let key = variant_access_key(&hash, &variant);
 
-        let identifier = identifier.to_bytes()?;
+        let variant_access = self.variant_access.clone();
+        let inverse_variant_access = self.inverse_variant_access.clone();
 
         actix_rt::task::spawn_blocking(move || {
-            if let Some(old) = identifier_access.remove(identifier)? {
-                inverse_identifier_access.remove(old)?;
+            if let Some(old) = variant_access.remove(key)? {
+                inverse_variant_access.remove(old)?;
             }
             Ok(()) as Result<(), SledError>
         })
         .await
         .map_err(|_| RepoError::Canceled)?
         .map_err(RepoError::from)
-        .map_err(StoreError::from)
     }
 }
 
@@ -648,6 +644,61 @@ impl SettingsRepo for SledRepo {
     }
 }
 
+fn variant_access_key(hash: &[u8], variant: &str) -> Vec<u8> {
+    let variant = variant.as_bytes();
+
+    let hash_len: u64 = u64::try_from(hash.len()).expect("Length is reasonable");
+
+    let mut out = Vec::with_capacity(8 + hash.len() + variant.len());
+
+    let hash_length_bytes: [u8; 8] = hash_len.to_be_bytes();
+    out.extend(hash_length_bytes);
+    out.extend(hash);
+    out.extend(variant);
+    out
+}
+
+#[derive(Debug, thiserror::Error)]
+pub(crate) enum VariantKeyError {
+    #[error("Bytes too short to be VariantAccessKey")]
+    TooShort,
+
+    #[error("Prefix Length is longer than backing bytes")]
+    InvalidLength,
+
+    #[error("Invalid utf8 in Variant")]
+    Utf8,
+}
+
+fn parse_variant_access_key(bytes: IVec) -> Result<(IVec, String), VariantKeyError> {
+    if bytes.len() < 8 {
+        return Err(VariantKeyError::TooShort);
+    }
+
+    let hash_len = u64::from_be_bytes(bytes[..8].try_into().expect("Verified length"));
+    let hash_len: usize = usize::try_from(hash_len).expect("Length is reasonable");
+
+    if (hash_len + 8) > bytes.len() {
+        return Err(VariantKeyError::InvalidLength);
+    }
+
+    let hash = bytes.subslice(8, hash_len);
+
+    let variant_len = bytes.len().saturating_sub(8).saturating_sub(hash_len);
+
+    if variant_len == 0 {
+        return Ok((hash, String::new()));
+    }
+
+    let variant_start = 8 + hash_len;
+
+    let variant = std::str::from_utf8(&bytes[variant_start..])
+        .map_err(|_| VariantKeyError::Utf8)?
+        .to_string();
+
+    Ok((hash, variant))
+}
+
 fn variant_key(hash: &[u8], variant: &str) -> Vec<u8> {
     let mut bytes = hash.to_vec();
     bytes.push(b'/');
@@ -1106,3 +1157,20 @@ impl From<actix_rt::task::JoinError> for SledError {
         SledError::Panic
     }
 }
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn round_trip() {
+        let hash = sled::IVec::from(b"some hash value");
+        let variant = String::from("some string value");
+
+        let key = super::variant_access_key(&hash, &variant);
+
+        let (out_hash, out_variant) =
+            super::parse_variant_access_key(sled::IVec::from(key)).expect("Parsed bytes");
+
+        assert_eq!(out_hash, hash);
+        assert_eq!(out_variant, variant);
+    }
+}