//! Function related to GET and HEAD requests
use std::sync::Arc;
use std::time::{Duration, UNIX_EPOCH};
use futures::stream::*;
use http::header::{
ACCEPT_RANGES, CONTENT_LENGTH, CONTENT_RANGE, CONTENT_TYPE, ETAG, IF_MODIFIED_SINCE,
IF_NONE_MATCH, LAST_MODIFIED, RANGE,
};
use hyper::body::Bytes;
use hyper::{Body, Request, Response, StatusCode};
use garage_table::EmptyKey;
use garage_util::data::*;
use garage_model::garage::Garage;
use garage_model::object_table::*;
use garage_model::version_table::*;
use crate::error::*;
const X_AMZ_MP_PARTS_COUNT: &str = "x-amz-mp-parts-count";
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
}
fn try_answer_cached(
version: &ObjectVersion,
version_meta: &ObjectVersionMeta,
req: &Request<Body>,
) -> Option<Response<Body>> {
// <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(Body::empty())
.unwrap(),
)
} else {
None
}
}
/// Handle HEAD request
pub async fn handle_head(
garage: Arc<Garage>,
req: &Request<Body>,
bucket_id: Uuid,
key: &str,
part_number: Option<u64>,
) -> Result<Response<Body>, 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(Body::empty())?)
}
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)?;
let n_parts = version.parts_etags.items().len();
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!("{}", n_parts))
.status(StatusCode::PARTIAL_CONTENT)
.body(Body::empty())?)
}
_ => unreachable!(),
}
} else {
Ok(object_headers(object_version, version_meta)
.header(CONTENT_LENGTH, format!("{}", version_meta.size))
.status(StatusCode::OK)
.body(Body::empty())?)
}
}
/// Handle GET request
pub async fn handle_get(
garage: Arc<Garage>,
req: &Request<Body>,
bucket_id: Uuid,
key: &str,
part_number: Option<u64>,
) -> Result<Response<Body>, 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::BadRequest(
"Cannot specify both partNumber and Range header".into(),
));
}
(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 resp_builder = object_headers(last_v, last_v_meta)
.header(CONTENT_LENGTH, format!("{}", last_v_meta.size))
.status(StatusCode::OK);
match &last_v_data {
ObjectVersionData::DeleteMarker => unreachable!(),
ObjectVersionData::Inline(_, bytes) => {
let body: Body = Body::from(bytes.to_vec());
Ok(resp_builder.body(body)?)
}
ObjectVersionData::FirstBlock(_, first_block_hash) => {
let read_first_block = garage.block_manager.rpc_get_block(first_block_hash);
let get_next_blocks = garage.version_table.get(&last_v.uuid, &EmptyKey);
let (first_block, version) = futures::try_join!(read_first_block, get_next_blocks)?;
let version = version.ok_or(Error::NoSuchKey)?;
let mut blocks = version
.blocks
.items()
.iter()
.map(|(_, vb)| (vb.hash, None))
.collect::<Vec<_>>();
blocks[0].1 = Some(first_block);
let body_stream = futures::stream::iter(blocks)
.map(move |(hash, data_opt)| {
let garage = garage.clone();
async move {
if let Some(data) = data_opt {
Ok(Bytes::from(data))
} else {
garage
.block_manager
.rpc_get_block(&hash)
.await
.map(Bytes::from)
}
}
})
.buffered(2);
let body = hyper::body::Body::wrap_stream(body_stream);
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<Body>, Error> {
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: Body = Body::from(bytes[begin as usize..end as usize].to_vec());
Ok(resp_builder.body(body)?)
} else {
None.ok_or_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<Body>, Error> {
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(Body::from(bytes.to_vec()))?)
}
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 n_parts = version.parts_etags.items().len();
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!("{}", n_parts))
.body(body)?)
}
_ => unreachable!(),
}
}
fn parse_range_header(
req: &Request<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,
) -> Body {
// 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 as u64, 1024)) as usize,
));
let mut true_offset = 0;
for (_, b) in all_blocks.iter() {
if true_offset >= end {
break;
}
// Keep only blocks that have an intersection with the requested range
if true_offset < end && true_offset + b.size > begin {
blocks.push((*b, true_offset));
}
true_offset += b.size;
}
let body_stream = futures::stream::iter(blocks)
.map(move |(block, true_offset)| {
let garage = garage.clone();
async move {
let data = garage.block_manager.rpc_get_block(&block.hash).await?;
let data = Bytes::from(data);
let start_in_block = if true_offset > begin {
0
} else {
begin - true_offset
};
let end_in_block = if true_offset + block.size < end {
block.size
} else {
end - true_offset
};
Result::<Bytes, Error>::Ok(
data.slice(start_in_block as usize..end_in_block as usize),
)
}
})
.buffered(2);
hyper::body::Body::wrap_stream(body_stream)
}
