garage/src/api/s3_copy.rs
2021-03-15 16:21:41 +01:00

172 lines
5.1 KiB
Rust

use std::fmt::Write;
use std::sync::Arc;
use hyper::{Body, Request, Response};
use garage_table::*;
use garage_util::data::*;
use garage_util::time::*;
use garage_model::block_ref_table::*;
use garage_model::garage::Garage;
use garage_model::object_table::*;
use garage_model::version_table::*;
use crate::error::*;
use crate::s3_put::get_headers;
pub async fn handle_copy(
garage: Arc<Garage>,
req: &Request<Body>,
dest_bucket: &str,
dest_key: &str,
source_bucket: &str,
source_key: &str,
) -> Result<Response<Body>, Error> {
let source_object = garage
.object_table
.get(&source_bucket.to_string(), &source_key.to_string())
.await?
.ok_or(Error::NotFound)?;
let source_last_v = source_object
.versions()
.iter()
.rev()
.filter(|v| v.is_complete())
.next()
.ok_or(Error::NotFound)?;
let source_last_state = match &source_last_v.state {
ObjectVersionState::Complete(x) => x,
_ => unreachable!(),
};
let new_uuid = gen_uuid();
let new_timestamp = now_msec();
// Implement x-amz-metadata-directive: REPLACE
let old_meta = match source_last_state {
ObjectVersionData::DeleteMarker => {
return Err(Error::NotFound);
}
ObjectVersionData::Inline(meta, _bytes) => meta,
ObjectVersionData::FirstBlock(meta, _fbh) => meta,
};
let new_meta = match req.headers().get("x-amz-metadata-directive") {
Some(v) if v == hyper::header::HeaderValue::from_static("REPLACE") => ObjectVersionMeta {
headers: get_headers(req)?,
size: old_meta.size,
etag: old_meta.etag.clone(),
},
_ => old_meta.clone(),
};
// Save object copy
match source_last_state {
ObjectVersionData::DeleteMarker => unreachable!(),
ObjectVersionData::Inline(_meta, bytes) => {
let dest_object_version = ObjectVersion {
uuid: new_uuid,
timestamp: new_timestamp,
state: ObjectVersionState::Complete(ObjectVersionData::Inline(
new_meta,
bytes.clone(),
)),
};
let dest_object = Object::new(
dest_bucket.to_string(),
dest_key.to_string(),
vec![dest_object_version],
);
garage.object_table.insert(&dest_object).await?;
}
ObjectVersionData::FirstBlock(_meta, first_block_hash) => {
// Get block list from source version
let source_version = garage
.version_table
.get(&source_last_v.uuid, &EmptyKey)
.await?;
let source_version = source_version.ok_or(Error::NotFound)?;
// Write an "uploading" marker in Object table
// This holds a reference to the object in the Version table
// so that it won't be deleted, e.g. by repair_versions.
let tmp_dest_object_version = ObjectVersion {
uuid: new_uuid,
timestamp: new_timestamp,
state: ObjectVersionState::Uploading(new_meta.headers.clone()),
};
let tmp_dest_object = Object::new(
dest_bucket.to_string(),
dest_key.to_string(),
vec![tmp_dest_object_version],
);
garage.object_table.insert(&tmp_dest_object).await?;
// Write version in the version table. Even with empty block list,
// this means that the BlockRef entries linked to this version cannot be
// marked as deleted (they are marked as deleted only if the Version
// doesn't exist or is marked as deleted).
let mut dest_version = Version::new(
new_uuid,
dest_bucket.to_string(),
dest_key.to_string(),
false,
);
garage.version_table.insert(&dest_version).await?;
// Fill in block list for version and insert block refs
for (bk, bv) in source_version.blocks.items().iter() {
dest_version.blocks.put(*bk, *bv);
}
let dest_block_refs = dest_version
.blocks
.items()
.iter()
.map(|b| BlockRef {
block: b.1.hash,
version: new_uuid,
deleted: false.into(),
})
.collect::<Vec<_>>();
futures::try_join!(
garage.version_table.insert(&dest_version),
garage.block_ref_table.insert_many(&dest_block_refs[..]),
)?;
// Insert final object
// We do this last because otherwise there is a race condition in the case where
// the copy call has the same source and destination (this happens, rclone does
// it to update the modification timestamp for instance). If we did this concurrently
// with the stuff before, the block's reference counts could be decremented before
// they are incremented again for the new version, leading to data being deleted.
let dest_object_version = ObjectVersion {
uuid: new_uuid,
timestamp: new_timestamp,
state: ObjectVersionState::Complete(ObjectVersionData::FirstBlock(
new_meta,
*first_block_hash,
)),
};
let dest_object = Object::new(
dest_bucket.to_string(),
dest_key.to_string(),
vec![dest_object_version],
);
garage.object_table.insert(&dest_object).await?;
}
}
let last_modified = msec_to_rfc3339(new_timestamp);
let mut xml = String::new();
writeln!(&mut xml, r#"<?xml version="1.0" encoding="UTF-8"?>"#).unwrap();
writeln!(&mut xml, r#"<CopyObjectResult>"#).unwrap();
writeln!(&mut xml, "\t<LastModified>{}</LastModified>", last_modified).unwrap();
writeln!(&mut xml, "</CopyObjectResult>").unwrap();
Ok(Response::builder()
.header("Content-Type", "application/xml")
.body(Body::from(xml.into_bytes()))?)
}