//! Function related to GET and HEAD requests use std::convert::TryInto; use std::sync::Arc; use std::time::{Duration, UNIX_EPOCH}; use futures::future; use futures::stream::{self, StreamExt}; use http::header::{ ACCEPT_RANGES, CACHE_CONTROL, CONTENT_DISPOSITION, CONTENT_ENCODING, CONTENT_LANGUAGE, CONTENT_LENGTH, CONTENT_RANGE, CONTENT_TYPE, ETAG, EXPIRES, IF_MODIFIED_SINCE, IF_NONE_MATCH, LAST_MODIFIED, RANGE, }; use hyper::{body::Body, Request, Response, StatusCode}; use tokio::sync::mpsc; use garage_block::manager::BlockStream; use garage_rpc::rpc_helper::OrderTag; use garage_table::EmptyKey; use garage_util::data::*; use garage_util::error::OkOrMessage; use garage_model::garage::Garage; use garage_model::s3::object_table::*; use garage_model::s3::version_table::*; use crate::helpers::*; use crate::s3::api_server::ResBody; use crate::s3::error::*; const X_AMZ_MP_PARTS_COUNT: &str = "x-amz-mp-parts-count"; #[derive(Default)] pub struct GetObjectOverrides { pub(crate) response_cache_control: Option<String>, pub(crate) response_content_disposition: Option<String>, pub(crate) response_content_encoding: Option<String>, pub(crate) response_content_language: Option<String>, pub(crate) response_content_type: Option<String>, pub(crate) response_expires: Option<String>, } fn object_headers( version: &ObjectVersion, version_meta: &ObjectVersionMeta, ) -> http::response::Builder { debug!("Version meta: {:?}", version_meta); let date = UNIX_EPOCH + Duration::from_millis(version.timestamp); let date_str = httpdate::fmt_http_date(date); let mut resp = Response::builder() .header(CONTENT_TYPE, version_meta.headers.content_type.to_string()) .header(LAST_MODIFIED, date_str) .header(ACCEPT_RANGES, "bytes".to_string()); if !version_meta.etag.is_empty() { resp = resp.header(ETAG, format!("\"{}\"", version_meta.etag)); } for (k, v) in version_meta.headers.other.iter() { resp = resp.header(k, v.to_string()); } resp } /// Override headers according to specific query parameters, see /// section "Overriding response header values through the request" in /// https://docs.aws.amazon.com/AmazonS3/latest/API/API_GetObject.html fn getobject_override_headers( overrides: GetObjectOverrides, resp: &mut http::response::Builder, ) -> Result<(), Error> { // TODO: this only applies for signed requests, so when we support // anonymous access in the future we will have to do a permission check here let overrides = [ (CACHE_CONTROL, overrides.response_cache_control), (CONTENT_DISPOSITION, overrides.response_content_disposition), (CONTENT_ENCODING, overrides.response_content_encoding), (CONTENT_LANGUAGE, overrides.response_content_language), (CONTENT_TYPE, overrides.response_content_type), (EXPIRES, overrides.response_expires), ]; for (hdr, val_opt) in overrides { if let Some(val) = val_opt { let val = val.try_into().ok_or_bad_request("invalid header value")?; resp.headers_mut().unwrap().insert(hdr, val); } } Ok(()) } fn try_answer_cached( version: &ObjectVersion, version_meta: &ObjectVersionMeta, req: &Request<impl Body>, ) -> Option<Response<ResBody>> { // <trinity> It is possible, and is even usually the case, [that both If-None-Match and // If-Modified-Since] are present in a request. In this situation If-None-Match takes // precedence and If-Modified-Since is ignored (as per 6.Precedence from rfc7232). The rational // being that etag based matching is more accurate, it has no issue with sub-second precision // for instance (in case of very fast updates) let cached = if let Some(none_match) = req.headers().get(IF_NONE_MATCH) { let none_match = none_match.to_str().ok()?; let expected = format!("\"{}\"", version_meta.etag); let found = none_match .split(',') .map(str::trim) .any(|etag| etag == expected || etag == "\"*\""); found } else if let Some(modified_since) = req.headers().get(IF_MODIFIED_SINCE) { let modified_since = modified_since.to_str().ok()?; let client_date = httpdate::parse_http_date(modified_since).ok()?; let server_date = UNIX_EPOCH + Duration::from_millis(version.timestamp); client_date >= server_date } else { false }; if cached { Some( Response::builder() .status(StatusCode::NOT_MODIFIED) .body(empty_body()) .unwrap(), ) } else { None } } /// Handle HEAD request pub async fn handle_head( garage: Arc<Garage>, req: &Request<impl Body>, bucket_id: Uuid, key: &str, part_number: Option<u64>, ) -> Result<Response<ResBody>, Error> { let object = garage .object_table .get(&bucket_id, &key.to_string()) .await? .ok_or(Error::NoSuchKey)?; let object_version = object .versions() .iter() .rev() .find(|v| v.is_data()) .ok_or(Error::NoSuchKey)?; let version_data = match &object_version.state { ObjectVersionState::Complete(c) => c, _ => unreachable!(), }; let version_meta = match version_data { ObjectVersionData::Inline(meta, _) => meta, ObjectVersionData::FirstBlock(meta, _) => meta, _ => unreachable!(), }; if let Some(cached) = try_answer_cached(object_version, version_meta, req) { return Ok(cached); } if let Some(pn) = part_number { match version_data { ObjectVersionData::Inline(_, bytes) => { if pn != 1 { return Err(Error::InvalidPart); } Ok(object_headers(object_version, version_meta) .header(CONTENT_LENGTH, format!("{}", bytes.len())) .header( CONTENT_RANGE, format!("bytes 0-{}/{}", bytes.len() - 1, bytes.len()), ) .header(X_AMZ_MP_PARTS_COUNT, "1") .status(StatusCode::PARTIAL_CONTENT) .body(empty_body())?) } ObjectVersionData::FirstBlock(_, _) => { let version = garage .version_table .get(&object_version.uuid, &EmptyKey) .await? .ok_or(Error::NoSuchKey)?; let (part_offset, part_end) = calculate_part_bounds(&version, pn).ok_or(Error::InvalidPart)?; Ok(object_headers(object_version, version_meta) .header(CONTENT_LENGTH, format!("{}", part_end - part_offset)) .header( CONTENT_RANGE, format!( "bytes {}-{}/{}", part_offset, part_end - 1, version_meta.size ), ) .header(X_AMZ_MP_PARTS_COUNT, format!("{}", version.n_parts()?)) .status(StatusCode::PARTIAL_CONTENT) .body(empty_body())?) } _ => unreachable!(), } } else { Ok(object_headers(object_version, version_meta) .header(CONTENT_LENGTH, format!("{}", version_meta.size)) .status(StatusCode::OK) .body(empty_body())?) } } /// Handle GET request pub async fn handle_get( garage: Arc<Garage>, req: &Request<impl Body>, bucket_id: Uuid, key: &str, part_number: Option<u64>, overrides: GetObjectOverrides, ) -> Result<Response<ResBody>, Error> { let object = garage .object_table .get(&bucket_id, &key.to_string()) .await? .ok_or(Error::NoSuchKey)?; let last_v = object .versions() .iter() .rev() .find(|v| v.is_complete()) .ok_or(Error::NoSuchKey)?; let last_v_data = match &last_v.state { ObjectVersionState::Complete(x) => x, _ => unreachable!(), }; let last_v_meta = match last_v_data { ObjectVersionData::DeleteMarker => return Err(Error::NoSuchKey), ObjectVersionData::Inline(meta, _) => meta, ObjectVersionData::FirstBlock(meta, _) => meta, }; if let Some(cached) = try_answer_cached(last_v, last_v_meta, req) { return Ok(cached); } match (part_number, parse_range_header(req, last_v_meta.size)?) { (Some(_), Some(_)) => { return Err(Error::bad_request( "Cannot specify both partNumber and Range header", )); } (Some(pn), None) => { return handle_get_part(garage, last_v, last_v_data, last_v_meta, pn).await; } (None, Some(range)) => { return handle_get_range( garage, last_v, last_v_data, last_v_meta, range.start, range.start + range.length, ) .await; } (None, None) => (), } let mut resp_builder = object_headers(last_v, last_v_meta) .header(CONTENT_LENGTH, format!("{}", last_v_meta.size)) .status(StatusCode::OK); getobject_override_headers(overrides, &mut resp_builder)?; match &last_v_data { ObjectVersionData::DeleteMarker => unreachable!(), ObjectVersionData::Inline(_, bytes) => { Ok(resp_builder.body(bytes_body(bytes.to_vec().into()))?) } ObjectVersionData::FirstBlock(_, first_block_hash) => { let (tx, rx) = mpsc::channel::<BlockStream>(2); let order_stream = OrderTag::stream(); let first_block_hash = *first_block_hash; let version_uuid = last_v.uuid; tokio::spawn(async move { match async { let garage2 = garage.clone(); let version_fut = tokio::spawn(async move { garage2.version_table.get(&version_uuid, &EmptyKey).await }); let stream_block_0 = garage .block_manager .rpc_get_block_streaming(&first_block_hash, Some(order_stream.order(0))) .await?; tx.send(stream_block_0) .await .ok_or_message("channel closed")?; let version = version_fut.await.unwrap()?.ok_or(Error::NoSuchKey)?; for (i, (_, vb)) in version.blocks.items().iter().enumerate().skip(1) { let stream_block_i = garage .block_manager .rpc_get_block_streaming(&vb.hash, Some(order_stream.order(i as u64))) .await?; tx.send(stream_block_i) .await .ok_or_message("channel closed")?; } Ok::<(), Error>(()) } .await { Ok(()) => (), Err(e) => { let _ = tx.send(error_stream_item(e)).await; } } }); let body = response_body_from_block_stream(rx); Ok(resp_builder.body(body)?) } } } async fn handle_get_range( garage: Arc<Garage>, version: &ObjectVersion, version_data: &ObjectVersionData, version_meta: &ObjectVersionMeta, begin: u64, end: u64, ) -> Result<Response<ResBody>, Error> { // Here we do not use getobject_override_headers because we don't // want to add any overridden headers (those should not be added // when returning PARTIAL_CONTENT) let resp_builder = object_headers(version, version_meta) .header(CONTENT_LENGTH, format!("{}", end - begin)) .header( CONTENT_RANGE, format!("bytes {}-{}/{}", begin, end - 1, version_meta.size), ) .status(StatusCode::PARTIAL_CONTENT); match &version_data { ObjectVersionData::DeleteMarker => unreachable!(), ObjectVersionData::Inline(_meta, bytes) => { if end as usize <= bytes.len() { let body = bytes_body(bytes[begin as usize..end as usize].to_vec().into()); Ok(resp_builder.body(body)?) } else { Err(Error::internal_error( "Requested range not present in inline bytes when it should have been", )) } } ObjectVersionData::FirstBlock(_meta, _first_block_hash) => { let version = garage .version_table .get(&version.uuid, &EmptyKey) .await? .ok_or(Error::NoSuchKey)?; let body = body_from_blocks_range(garage, version.blocks.items(), begin, end); Ok(resp_builder.body(body)?) } } } async fn handle_get_part( garage: Arc<Garage>, object_version: &ObjectVersion, version_data: &ObjectVersionData, version_meta: &ObjectVersionMeta, part_number: u64, ) -> Result<Response<ResBody>, Error> { // Same as for get_range, no getobject_override_headers let resp_builder = object_headers(object_version, version_meta).status(StatusCode::PARTIAL_CONTENT); match version_data { ObjectVersionData::Inline(_, bytes) => { if part_number != 1 { return Err(Error::InvalidPart); } Ok(resp_builder .header(CONTENT_LENGTH, format!("{}", bytes.len())) .header( CONTENT_RANGE, format!("bytes {}-{}/{}", 0, bytes.len() - 1, bytes.len()), ) .header(X_AMZ_MP_PARTS_COUNT, "1") .body(bytes_body(bytes.to_vec().into()))?) } ObjectVersionData::FirstBlock(_, _) => { let version = garage .version_table .get(&object_version.uuid, &EmptyKey) .await? .ok_or(Error::NoSuchKey)?; let (begin, end) = calculate_part_bounds(&version, part_number).ok_or(Error::InvalidPart)?; let body = body_from_blocks_range(garage, version.blocks.items(), begin, end); Ok(resp_builder .header(CONTENT_LENGTH, format!("{}", end - begin)) .header( CONTENT_RANGE, format!("bytes {}-{}/{}", begin, end - 1, version_meta.size), ) .header(X_AMZ_MP_PARTS_COUNT, format!("{}", version.n_parts()?)) .body(body)?) } _ => unreachable!(), } } fn parse_range_header( req: &Request<impl Body>, total_size: u64, ) -> Result<Option<http_range::HttpRange>, Error> { let range = match req.headers().get(RANGE) { Some(range) => { let range_str = range.to_str()?; let mut ranges = http_range::HttpRange::parse(range_str, total_size).map_err(|e| (e, total_size))?; if ranges.len() > 1 { // garage does not support multi-range requests yet, so we respond with the entire // object when multiple ranges are requested None } else { ranges.pop() } } None => None, }; Ok(range) } fn calculate_part_bounds(v: &Version, part_number: u64) -> Option<(u64, u64)> { let mut offset = 0; for (i, (bk, bv)) in v.blocks.items().iter().enumerate() { if bk.part_number == part_number { let size: u64 = v.blocks.items()[i..] .iter() .take_while(|(k, _)| k.part_number == part_number) .map(|(_, v)| v.size) .sum(); return Some((offset, offset + size)); } offset += bv.size; } None } fn body_from_blocks_range( garage: Arc<Garage>, all_blocks: &[(VersionBlockKey, VersionBlock)], begin: u64, end: u64, ) -> ResBody { // We will store here the list of blocks that have an intersection with the requested // range, as well as their "true offset", which is their actual offset in the complete // file (whereas block.offset designates the offset of the block WITHIN THE PART // block.part_number, which is not the same in the case of a multipart upload) let mut blocks: Vec<(VersionBlock, u64)> = Vec::with_capacity(std::cmp::min( all_blocks.len(), 4 + ((end - begin) / std::cmp::max(all_blocks[0].1.size, 1024)) as usize, )); let mut block_offset: u64 = 0; for (_, b) in all_blocks.iter() { if block_offset >= end { break; } // Keep only blocks that have an intersection with the requested range if block_offset < end && block_offset + b.size > begin { blocks.push((*b, block_offset)); } block_offset += b.size; } let order_stream = OrderTag::stream(); let (tx, rx) = mpsc::channel::<BlockStream>(2); tokio::spawn(async move { match async { let garage = garage.clone(); for (i, (block, block_offset)) in blocks.iter().enumerate() { let block_stream = garage .block_manager .rpc_get_block_streaming(&block.hash, Some(order_stream.order(i as u64))) .await? .scan(*block_offset, move |chunk_offset, chunk| { let r = match chunk { Ok(chunk_bytes) => { let chunk_len = chunk_bytes.len() as u64; let r = if *chunk_offset >= end { // The current chunk is after the part we want to read. // Returning None here will stop the scan, the rest of the // stream will be ignored None } else if *chunk_offset + chunk_len <= begin { // The current chunk is before the part we want to read. // We return a None that will be removed by the filter_map // below. Some(None) } else { // The chunk has an intersection with the requested range let start_in_chunk = if *chunk_offset > begin { 0 } else { begin - *chunk_offset }; let end_in_chunk = if *chunk_offset + chunk_len < end { chunk_len } else { end - *chunk_offset }; Some(Some(Ok(chunk_bytes .slice(start_in_chunk as usize..end_in_chunk as usize)))) }; *chunk_offset += chunk_bytes.len() as u64; r } Err(e) => Some(Some(Err(e))), }; futures::future::ready(r) }) .filter_map(futures::future::ready); let block_stream: BlockStream = Box::pin(block_stream); tx.send(Box::pin(block_stream)) .await .ok_or_message("channel closed")?; } Ok::<(), Error>(()) } .await { Ok(()) => (), Err(e) => { let _ = tx.send(error_stream_item(e)).await; } } }); response_body_from_block_stream(rx) } fn response_body_from_block_stream(rx: mpsc::Receiver<BlockStream>) -> ResBody { let body_stream = tokio_stream::wrappers::ReceiverStream::new(rx) .flatten() .map(|x| { x.map(hyper::body::Frame::data) .map_err(|e| Error::from(garage_util::error::Error::from(e))) }); ResBody::new(http_body_util::StreamBody::new(body_stream)) } fn error_stream_item<E: std::fmt::Display>(e: E) -> BlockStream { let err = std::io::Error::new( std::io::ErrorKind::Other, format!("Error while getting object data: {}", e), ); Box::pin(stream::once(future::ready(Err(err)))) }