Implement most of new git implementation's get_file method

This includes a refactoring of get_file to be completely async, as well
as to add a new error case.

Cargo.lock

@@ -2731,6 +2731,7 @@ dependencies = [
  "url",
  "wasm-bindgen",
  "wasm-bindgen-futures",
+ "wasm-streams",
  "web-sys",
  "webpki-roots 0.25.3",
  "winreg 0.50.0",
@@ -3713,6 +3714,19 @@ version = "0.2.84"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0046fef7e28c3804e5e38bfa31ea2a0f73905319b677e57ebe37e49358989b5d"
 
+[[package]]
+name = "wasm-streams"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b4609d447824375f43e1ffbc051b50ad8f4b3ae8219680c94452ea05eb240ac7"
+dependencies = [
+ "futures-util",
+ "js-sys",
+ "wasm-bindgen",
+ "wasm-bindgen-futures",
+ "web-sys",
+]
+
 [[package]]
 name = "web-sys"
 version = "0.3.61"

Cargo.toml

@@ -47,7 +47,7 @@ gemini = "0.0.5"
 bytes = "1.4.0"
 hyper-trust-dns = "0.5.0"
 gix-hash = "0.14.1"
-reqwest = { version = "0.11.23", features = ["gzip", "deflate"] }
+reqwest = { version = "0.11.23", features = ["gzip", "deflate", "stream"] }
 gix-object = "0.41.0"
 
 [patch.crates-io]

src/domain/manager.rs

@@ -40,6 +40,9 @@ pub enum SyncWithSettingsError {
     #[error("invalid url")]
     InvalidURL,
 
+    #[error("unavailable due to server-side issue")]
+    Unavailable,
+
     #[error("invalid branch name")]
     InvalidBranchName,
 
@@ -60,6 +63,7 @@ impl From<origin::SyncError> for SyncWithSettingsError {
     fn from(e: origin::SyncError) -> SyncWithSettingsError {
         match e {
             origin::SyncError::InvalidURL => SyncWithSettingsError::InvalidURL,
+            origin::SyncError::Unavailable => SyncWithSettingsError::Unavailable,
             origin::SyncError::InvalidBranchName => SyncWithSettingsError::InvalidBranchName,
             origin::SyncError::AlreadyInProgress => SyncWithSettingsError::AlreadyInProgress,
             origin::SyncError::Unexpected(e) => SyncWithSettingsError::Unexpected(e),
@@ -96,7 +100,7 @@ pub trait Manager: Sync + Send {
         &self,
         settings: &domain::Settings,
         path: &str,
-    ) -> Result<util::BoxByteStream, GetFileError>;
+    ) -> util::BoxFuture<'_, Result<util::BoxByteStream, GetFileError>>;
 
     fn sync_with_settings(
         &self,
@@ -397,7 +401,7 @@ impl Manager for ManagerImpl {
         &self,
         settings: &domain::Settings,
         path: &str,
-    ) -> Result<util::BoxByteStream, GetFileError> {
+    ) -> util::BoxFuture<'_, Result<util::BoxByteStream, GetFileError>> {
         let path = settings.process_path(path);
         self.origin_store
             .get_file(&settings.origin_descr, path.as_ref())

src/main.rs

@@ -90,6 +90,8 @@ async fn main() {
     let origin_store = domani::origin::git::FSStore::new(&config.origin)
         .expect("git origin store initialization failed");
 
+    //let origin_store = domani::origin::git_proxy::Proxy::new();
+
     let domain_checker = domani::domain::checker::DNSChecker::new(
         domani::token::MemStore::new(),
         &config.domain.dns,

src/origin.rs

@@ -15,6 +15,9 @@ pub enum SyncError {
     #[error("invalid url")]
     InvalidURL,
 
+    #[error("unavailable due to server-side issue")]
+    Unavailable,
+
     #[error("invalid branch name")]
     InvalidBranchName,
 
@@ -33,6 +36,9 @@ pub enum GetFileError {
     #[error("file not found")]
     FileNotFound,
 
+    #[error("unavailable due to server-side issue")]
+    Unavailable,
+
     #[error("path is directory")]
     PathIsDirectory,
 
@@ -46,5 +52,10 @@ pub trait Store {
     /// the origin into the storage.
     fn sync(&self, descr: &Descr) -> util::BoxFuture<'_, Result<(), SyncError>>;
 
-    fn get_file(&self, descr: &Descr, path: &str) -> Result<util::BoxByteStream, GetFileError>;
+    /// Returns the body of the descr's given path, where path must be absolute.
+    fn get_file(
+        &self,
+        descr: &Descr,
+        path: &str,
+    ) -> util::BoxFuture<'_, Result<util::BoxByteStream, GetFileError>>;
 }

src/origin/git.rs

@@ -278,53 +278,60 @@ impl super::Store for FSStore {
         &self,
         descr: &origin::Descr,
         path: &str,
-    ) -> Result<util::BoxByteStream, origin::GetFileError> {
-        let repo_snapshot = match self.get_repo_snapshot(descr) {
-            Ok(Some(repo_snapshot)) => repo_snapshot,
-            Ok(None) => return Err(origin::GetFileError::DescrNotSynced),
-            Err(e) => return Err(e.into()),
-        };
+    ) -> util::BoxFuture<Result<util::BoxByteStream, origin::GetFileError>> {
+        let descr = descr.clone();
+        let path = path.to_string();
+        Box::pin(async move {
+            let repo_snapshot = match self.get_repo_snapshot(&descr) {
+                Ok(Some(repo_snapshot)) => repo_snapshot,
+                Ok(None) => return Err(origin::GetFileError::DescrNotSynced),
+                Err(e) => return Err(e.into()),
+            };
+
+            let mut clean_path = Path::new(path.as_str());
+            clean_path = clean_path.strip_prefix("/").unwrap_or(clean_path);
 
-        let mut clean_path = Path::new(path);
-        clean_path = clean_path.strip_prefix("/").unwrap_or(clean_path);
-
-        let repo = repo_snapshot.repo.to_thread_local();
-
-        let file_object = repo
-            .find_object(repo_snapshot.tree_object_id)
-            .map_unexpected_while(|| {
-                format!("finding tree object {}", repo_snapshot.tree_object_id)
-            })?
-            .peel_to_tree()
-            .map_unexpected_while(|| {
-                format!("peeling tree object {}", repo_snapshot.tree_object_id)
-            })?
-            .lookup_entry_by_path(clean_path)
-            .map_unexpected_while(|| {
-                format!(
-                    "looking up {} in tree object {}",
-                    clean_path.display(),
-                    repo_snapshot.tree_object_id
+            let repo = repo_snapshot.repo.to_thread_local();
+
+            let file_object = repo
+                .find_object(repo_snapshot.tree_object_id)
+                .map_unexpected_while(|| {
+                    format!("finding tree object {}", repo_snapshot.tree_object_id)
+                })?
+                .peel_to_tree()
+                .map_unexpected_while(|| {
+                    format!("peeling tree object {}", repo_snapshot.tree_object_id)
+                })?
+                .lookup_entry_by_path(clean_path)
+                .map_unexpected_while(|| {
+                    format!(
+                        "looking up {} in tree object {}",
+                        clean_path.display(),
+                        repo_snapshot.tree_object_id
+                    )
+                })?
+                .ok_or(origin::GetFileError::FileNotFound)?
+                .object()
+                .or_unexpected()?;
+
+            use gix::object::Kind;
+            match file_object.kind {
+                Kind::Tree => Err(origin::GetFileError::PathIsDirectory),
+                Kind::Blob => {
+                    // TODO this is very not ideal, the whole file is first read totally into memory, and then
+                    // that is cloned.
+                    let data = bytes::Bytes::copy_from_slice(file_object.data.as_slice());
+
+                    Ok(util::into_box_byte_stream(stream::once(
+                        async move { Ok(data) },
+                    )))
+                }
+                Kind::Commit | Kind::Tag => Err(unexpected::Error::from(
+                    format!("found object of kind {} in tree", file_object.kind).as_str(),
                 )
-            })?
-            .ok_or(origin::GetFileError::FileNotFound)?
-            .object()
-            .or_unexpected()?;
-
-        use gix::object::Kind;
-        match file_object.kind {
-            Kind::Tree => Err(origin::GetFileError::PathIsDirectory),
-            Kind::Blob => {
-                // TODO this is very not ideal, the whole file is first read totally into memory, and then
-                // that is cloned.
-                let data = bytes::Bytes::copy_from_slice(file_object.data.as_slice());
-                Ok(Box::pin(stream::once(async move { Ok(data) })))
+                .into()),
             }
-            Kind::Commit | Kind::Tag => Err(unexpected::Error::from(
-                format!("found object of kind {} in tree", file_object.kind).as_str(),
-            )
-            .into()),
-        }
+        })
     }
 }
 

src/origin/git_proxy.rs

@@ -2,6 +2,7 @@ use crate::error::unexpected::{self, Mappable};
 use crate::{origin, util};
 use std::{collections, sync};
 
+#[derive(Clone)]
 struct DescrState {
     current_tree: gix_hash::ObjectId,
 }
@@ -97,39 +98,78 @@ impl Proxy {
         Err(origin::SyncError::InvalidBranchName)
     }
 
-    async fn get_commit_tree(
+    async fn get_object(
         &self,
         descr: &origin::Descr,
-        commit_hash: &gix_hash::ObjectId,
-    ) -> Result<gix_hash::ObjectId, origin::SyncError> {
-        let hex = commit_hash.to_string();
+        oid: &gix_hash::ObjectId,
+    ) -> unexpected::Result<Option<reqwest::Response>> {
+        let hex = oid.to_string();
         let (url, _) = Self::deconstruct_descr(descr);
 
-        let commit_object_url = Self::construct_url(
+        let object_url = Self::construct_url(
             url,
             format!("/objects/{}/{}", &hex[..2], &hex[2..]).as_str(),
         )
         .or_unexpected_while("constructing refs url")?;
 
-        let commit_object_bytes = self
+        Ok(self
             .client
-            .get(commit_object_url)
+            .get(object_url)
             .send()
             .await
-            .or(Err(origin::SyncError::InvalidURL))?
+            .or_unexpected_while("performing request")?
             .error_for_status()
-            .or(Err(origin::SyncError::InvalidURL))?
+            .ok())
+    }
+
+    async fn get_commit_tree(
+        &self,
+        descr: &origin::Descr,
+        commit_hash: &gix_hash::ObjectId,
+    ) -> Result<gix_hash::ObjectId, origin::SyncError> {
+        let commit_object_bytes = self
+            .get_object(descr, commit_hash)
+            .await?
+            .ok_or(origin::SyncError::Unavailable)?
             .bytes()
             .await
-            .or(Err(origin::SyncError::InvalidURL))?;
+            .or(Err(origin::SyncError::Unavailable))?;
 
         let commit_object = gix_object::ObjectRef::from_loose(commit_object_bytes.as_ref())
-            .or(Err(origin::SyncError::InvalidURL))?
+            .or(Err(origin::SyncError::Unavailable))?
             .into_commit()
-            .ok_or(origin::SyncError::InvalidURL)?;
+            .ok_or(origin::SyncError::Unavailable)?;
 
         Ok(commit_object.tree())
     }
+
+    async fn get_tree_entry(
+        &self,
+        descr: &origin::Descr,
+        tree_hash: &gix_hash::ObjectId,
+        entry_name: &str,
+    ) -> Result<gix_object::tree::Entry, origin::GetFileError> {
+        let tree_object_bytes = self
+            .get_object(descr, tree_hash)
+            .await?
+            .ok_or(origin::GetFileError::Unavailable)?
+            .bytes()
+            .await
+            .or(Err(origin::GetFileError::Unavailable))?;
+
+        let tree_object = gix_object::ObjectRef::from_loose(tree_object_bytes.as_ref())
+            .or(Err(origin::GetFileError::Unavailable))?
+            .into_tree()
+            .ok_or(origin::GetFileError::Unavailable)?;
+
+        for entry in tree_object.entries {
+            if entry.filename == entry_name {
+                return Ok(entry.into());
+            }
+        }
+
+        Err(origin::GetFileError::FileNotFound)
+    }
 }
 
 impl origin::Store for Proxy {
@@ -170,9 +210,97 @@ impl origin::Store for Proxy {
 
     fn get_file(
         &self,
-        _descr: &origin::Descr,
-        _path: &str,
-    ) -> Result<util::BoxByteStream, origin::GetFileError> {
-        panic!("TODO")
+        descr: &origin::Descr,
+        path: &str,
+    ) -> util::BoxFuture<'_, Result<util::BoxByteStream, origin::GetFileError>> {
+        let descr = descr.clone();
+        let path = path.to_string();
+        Box::pin(async move {
+            let current_state = self
+                .state
+                .read()
+                .unwrap()
+                .get(&descr)
+                .ok_or(origin::GetFileError::DescrNotSynced)?
+                .clone();
+
+            let path = path
+                .as_str()
+                .parse::<std::path::PathBuf>()
+                .or_unexpected_while("parsing path")?
+                .canonicalize()
+                .or_unexpected_while("canonicalizing path")?;
+
+            let path_parts = path.iter().collect::<Vec<&std::ffi::OsStr>>();
+
+            let path_parts_len = path_parts.len();
+
+            if path_parts_len < 2 {
+                return Err(unexpected::Error::from("path has fewer than 2 parts").into());
+            } else if path_parts[0] != std::path::MAIN_SEPARATOR_STR {
+                return Err(unexpected::Error::from(format!(
+                    "expected first path part to be separator, found {:?}",
+                    path_parts[0]
+                ))
+                .into());
+            }
+
+            let mut tree_hash = current_state.current_tree;
+
+            // The first part is "/" (main separator), and the last is the file name itself.
+            // Everything in between (if any) should be directories, so navigate those.
+            for dir_name in path_parts[1..path_parts_len - 1].iter() {
+                let entry = self
+                    .get_tree_entry(
+                        &descr,
+                        &tree_hash,
+                        dir_name
+                            .to_str()
+                            .map_unexpected_while(|| format!("decoding dir name {dir_name:?}"))?,
+                    )
+                    .await?;
+
+                if !entry.mode.is_tree() {
+                    return Err(origin::GetFileError::FileNotFound);
+                }
+
+                tree_hash = entry.oid;
+            }
+
+            let file_name = {
+                let file_name = path_parts[path_parts_len - 1];
+                file_name
+                    .to_str()
+                    .map_unexpected_while(|| format!("decoding file name {file_name:?}"))?
+            };
+
+            let entry = self.get_tree_entry(&descr, &tree_hash, file_name).await?;
+
+            // TODO handle symlinks
+            if entry.mode.is_tree() {
+                return Err(origin::GetFileError::PathIsDirectory);
+            } else if !entry.mode.is_blob() {
+                return Err(unexpected::Error::from(format!(
+                    "can't handle entry {} of mode {}",
+                    entry.filename,
+                    entry.mode.as_str()
+                ))
+                .into());
+            }
+
+            let res = self
+                .get_object(&descr, &entry.oid)
+                .await?
+                .map_unexpected_while(|| format!("object for entry {:?} not found", entry))?
+                .bytes_stream();
+
+            use futures::StreamExt;
+            Ok(util::into_box_byte_stream(res.map(|r| {
+                use std::io::{Error, ErrorKind};
+                r.map_err(|e| Error::new(ErrorKind::ConnectionAborted, e))
+            })))
+
+            // TODO this is still not correct, as it will include the git object header
+        })
     }
 }

src/origin/mux.rs

@@ -37,9 +37,14 @@ where
         &self,
         descr: &origin::Descr,
         path: &str,
-    ) -> Result<util::BoxByteStream, origin::GetFileError> {
-        (self.mapping_fn)(descr)
-            .or_unexpected_while(format!("mapping {:?} to store", &descr))?
-            .get_file(descr, path)
+    ) -> util::BoxFuture<Result<util::BoxByteStream, origin::GetFileError>> {
+        let descr = descr.clone();
+        let path = path.to_string();
+        Box::pin(async move {
+            (self.mapping_fn)(&descr)
+                .or_unexpected_while(format!("mapping {:?} to store", &descr))?
+                .get_file(&descr, &path)
+                .await
+        })
     }
 }

src/service/gemini.rs

@@ -98,11 +98,16 @@ impl Service {
         let path = service::append_index_to_path(req.path(), "index.gmi");
 
         use domain::manager::GetFileError;
-        let f = match self.domain_manager.get_file(settings, &path) {
+        let f = match self.domain_manager.get_file(settings, &path).await {
             Ok(f) => f,
             Err(GetFileError::FileNotFound) => {
                 return Ok(self.respond_conn(w, "51", "File not found", None).await?)
             }
+            Err(GetFileError::Unavailable) => {
+                return Ok(self
+                    .respond_conn(w, "43", "Content unavailable", None)
+                    .await?)
+            }
             Err(GetFileError::DescrNotSynced) => {
                 return Err(unexpected::Error::from(
                     format!(

src/service/http.rs

@@ -218,9 +218,10 @@ impl Service {
         let path = service::append_index_to_path(req.uri().path(), "index.html");
 
         use domain::manager::GetFileError;
-        match self.domain_manager.get_file(&settings, &path) {
+        match self.domain_manager.get_file(&settings, &path).await {
             Ok(f) => self.serve(200, &path, Body::wrap_stream(f)),
             Err(GetFileError::FileNotFound) => self.render_error_page(404, "File not found"),
+            Err(GetFileError::Unavailable) => self.render_error_page(502, "Content unavailable"),
             Err(GetFileError::DescrNotSynced) => self.internal_error(
                 format!(
                     "Backend for {:?} has not yet been synced",
@@ -408,6 +409,11 @@ impl Service {
                     .to_string(),
             ), false),
 
+            Err(domain::manager::SyncWithSettingsError::Unavailable) => (Some(
+                "Fetching the git repository failed; the server is not available or is not corectly serving the repository."
+                    .to_string(),
+            ), false),
+
             Err(domain::manager::SyncWithSettingsError::InvalidBranchName) => (Some(
                 "The git repository does not have a branch of the given name; please double check
                 that you input the correct name."

src/util.rs

@@ -33,4 +33,11 @@ pub fn parse_file<T: std::str::FromStr>(
 
 pub type BoxByteStream = futures::stream::BoxStream<'static, io::Result<bytes::Bytes>>;
 
+pub fn into_box_byte_stream<T>(v: T) -> BoxByteStream
+where
+    T: futures::stream::Stream<Item = std::io::Result<bytes::Bytes>> + Send + 'static,
+{
+    Box::into_pin(Box::new(v))
+}
+
 pub type BoxFuture<'a, O> = pin::Pin<Box<dyn futures::Future<Output = O> + Send + 'a>>;