src/api2/backup.rs

   1 use failure::*;
   2 use futures::*;
   3 use hyper::header::{HeaderValue, UPGRADE};
   4 use hyper::http::request::Parts;
   5 use hyper::{Body, Response, StatusCode};
   6 use serde_json::{json, Value};
   7
   8 use proxmox::{sortable, identity, list_subdirs_api_method};
   9 use proxmox::api::{ApiResponseFuture, ApiHandler, ApiMethod, Router, RpcEnvironment};
  10 use proxmox::api::router::SubdirMap;
  11 use proxmox::api::schema::*;
  12
  13 use crate::tools::{self, WrappedReaderStream};
  14 use crate::server::{WorkerTask, H2Service};
  15 use crate::backup::*;
  16 use crate::api2::types::*;
  17
  18 mod environment;
  19 use environment::*;
  20
  21 mod upload_chunk;
  22 use upload_chunk::*;
  23
  24 pub const ROUTER: Router = Router::new()
  25     .upgrade(&API_METHOD_UPGRADE_BACKUP);
  26
  27 #[sortable]
  28 pub const API_METHOD_UPGRADE_BACKUP: ApiMethod = ApiMethod::new(
  29     &ApiHandler::AsyncHttp(&upgrade_to_backup_protocol),
  30     &ObjectSchema::new(
  31         concat!("Upgraded to backup protocol ('", PROXMOX_BACKUP_PROTOCOL_ID_V1!(), "')."),
  32         &sorted!([
  33             ("store", false, &DATASTORE_SCHEMA),
  34             ("backup-type", false, &BACKUP_TYPE_SCHEMA),
  35             ("backup-id", false, &BACKUP_ID_SCHEMA),
  36             ("backup-time", false, &BACKUP_TIME_SCHEMA),
  37             ("debug", true, &BooleanSchema::new("Enable verbose debug logging.").schema()),
  38         ]),
  39     )
  40 );
  41
  42 fn upgrade_to_backup_protocol(
  43     parts: Parts,
  44     req_body: Body,
  45     param: Value,
  46     _info: &ApiMethod,
  47     rpcenv: Box<dyn RpcEnvironment>,
  48 ) -> ApiResponseFuture {
  49
  50     async move {
  51     let debug = param["debug"].as_bool().unwrap_or(false);
  52
  53     let store = tools::required_string_param(&param, "store")?.to_owned();
  54     let datastore = DataStore::lookup_datastore(&store)?;
  55
  56     let backup_type = tools::required_string_param(&param, "backup-type")?;
  57     let backup_id = tools::required_string_param(&param, "backup-id")?;
  58     let backup_time = tools::required_integer_param(&param, "backup-time")?;
  59
  60     let protocols = parts
  61         .headers
  62         .get("UPGRADE")
  63         .ok_or_else(|| format_err!("missing Upgrade header"))?
  64         .to_str()?;
  65
  66     if protocols != PROXMOX_BACKUP_PROTOCOL_ID_V1!() {
  67         bail!("invalid protocol name");
  68     }
  69
  70     if parts.version >=  http::version::Version::HTTP_2 {
  71         bail!("unexpected http version '{:?}' (expected version < 2)", parts.version);
  72     }
  73
  74     let worker_id = format!("{}_{}_{}", store, backup_type, backup_id);
  75
  76     let username = rpcenv.get_user().unwrap();
  77     let env_type = rpcenv.env_type();
  78
  79     let backup_group = BackupGroup::new(backup_type, backup_id);
  80     let last_backup = BackupInfo::last_backup(&datastore.base_path(), &backup_group).unwrap_or(None);
  81     let backup_dir = BackupDir::new_with_group(backup_group, backup_time);
  82
  83     if let Some(last) = &last_backup {
  84         if backup_dir.backup_time() <= last.backup_dir.backup_time() {
  85             bail!("backup timestamp is older than last backup.");
  86         }
  87         // fixme: abort if last backup is still running - howto test?
  88         // Idea: write upid into a file inside snapshot dir. then test if
  89         // it is still running here.
  90     }
  91
  92     let (path, is_new) = datastore.create_backup_dir(&backup_dir)?;
  93     if !is_new { bail!("backup directorty already exists."); }
  94
  95     WorkerTask::spawn("backup", Some(worker_id), &username.clone(), true, move |worker| {
  96         let mut env = BackupEnvironment::new(
  97             env_type, username.clone(), worker.clone(), datastore, backup_dir);
  98
  99         env.debug = debug;
 100         env.last_backup = last_backup;
 101
 102         env.log(format!("starting new backup on datastore '{}': {:?}", store, path));
 103
 104         let service = H2Service::new(env.clone(), worker.clone(), &BACKUP_API_ROUTER, debug);
 105
 106         let abort_future = worker.abort_future();
 107
 108         let env2 = env.clone();
 109
 110         let mut req_fut = req_body
 111             .on_upgrade()
 112             .map_err(Error::from)
 113             .and_then(move |conn| {
 114                 env2.debug("protocol upgrade done");
 115
 116                 let mut http = hyper::server::conn::Http::new();
 117                 http.http2_only(true);
 118                 // increase window size: todo - find optiomal size
 119                 let window_size = 32*1024*1024; // max = (1 << 31) - 2
 120                 http.http2_initial_stream_window_size(window_size);
 121                 http.http2_initial_connection_window_size(window_size);
 122
 123                 http.serve_connection(conn, service)
 124                     .map_err(Error::from)
 125             });
 126         let mut abort_future = abort_future
 127             .map(|_| Err(format_err!("task aborted")));
 128
 129         async move {
 130             let res = select!{
 131                 req = req_fut => req,
 132                 abrt = abort_future => abrt,
 133             };
 134
 135             match (res, env.ensure_finished()) {
 136                 (Ok(_), Ok(())) => {
 137                     env.log("backup finished sucessfully");
 138                     Ok(())
 139                 },
 140                 (Err(err), Ok(())) => {
 141                     // ignore errors after finish
 142                     env.log(format!("backup had errors but finished: {}", err));
 143                     Ok(())
 144                 },
 145                 (Ok(_), Err(err)) => {
 146                     env.log(format!("backup ended and finish failed: {}", err));
 147                     env.log("removing unfinished backup");
 148                     env.remove_backup()?;
 149                     Err(err)
 150                 },
 151                 (Err(err), Err(_)) => {
 152                     env.log(format!("backup failed: {}", err));
 153                     env.log("removing failed backup");
 154                     env.remove_backup()?;
 155                     Err(err)
 156                 },
 157             }
 158         }
 159     })?;
 160
 161     let response = Response::builder()
 162         .status(StatusCode::SWITCHING_PROTOCOLS)
 163         .header(UPGRADE, HeaderValue::from_static(PROXMOX_BACKUP_PROTOCOL_ID_V1!()))
 164         .body(Body::empty())?;
 165
 166     Ok(response)
 167     }.boxed()
 168 }
 169
 170 pub const BACKUP_API_SUBDIRS: SubdirMap = &[
 171     (
 172         "blob", &Router::new()
 173             .upload(&API_METHOD_UPLOAD_BLOB)
 174     ),
 175     (
 176         "dynamic_chunk", &Router::new()
 177             .upload(&API_METHOD_UPLOAD_DYNAMIC_CHUNK)
 178     ),
 179     (
 180         "dynamic_close", &Router::new()
 181             .post(&API_METHOD_CLOSE_DYNAMIC_INDEX)
 182     ),
 183     (
 184         "dynamic_index", &Router::new()
 185             .download(&API_METHOD_DYNAMIC_CHUNK_INDEX)
 186             .post(&API_METHOD_CREATE_DYNAMIC_INDEX)
 187             .put(&API_METHOD_DYNAMIC_APPEND)
 188     ),
 189     (
 190         "finish", &Router::new()
 191             .post(
 192                 &ApiMethod::new(
 193                     &ApiHandler::Sync(&finish_backup),
 194                     &ObjectSchema::new("Mark backup as finished.", &[])
 195                 )
 196             )
 197     ),
 198     (
 199         "fixed_chunk", &Router::new()
 200             .upload(&API_METHOD_UPLOAD_FIXED_CHUNK)
 201     ),
 202     (
 203         "fixed_close", &Router::new()
 204             .post(&API_METHOD_CLOSE_FIXED_INDEX)
 205     ),
 206     (
 207         "fixed_index", &Router::new()
 208             .download(&API_METHOD_FIXED_CHUNK_INDEX)
 209             .post(&API_METHOD_CREATE_FIXED_INDEX)
 210             .put(&API_METHOD_FIXED_APPEND)
 211     ),
 212     (
 213         "speedtest", &Router::new()
 214             .upload(&API_METHOD_UPLOAD_SPEEDTEST)
 215     ),
 216 ];
 217
 218 pub const BACKUP_API_ROUTER: Router = Router::new()
 219     .get(&list_subdirs_api_method!(BACKUP_API_SUBDIRS))
 220     .subdirs(BACKUP_API_SUBDIRS);
 221
 222 #[sortable]
 223 pub const API_METHOD_CREATE_DYNAMIC_INDEX: ApiMethod = ApiMethod::new(
 224     &ApiHandler::Sync(&create_dynamic_index),
 225     &ObjectSchema::new(
 226         "Create dynamic chunk index file.",
 227         &sorted!([
 228             ("archive-name", false, &crate::api2::types::BACKUP_ARCHIVE_NAME_SCHEMA),
 229         ]),
 230     )
 231 );
 232
 233 fn create_dynamic_index(
 234     param: Value,
 235     _info: &ApiMethod,
 236     rpcenv: &mut dyn RpcEnvironment,
 237 ) -> Result<Value, Error> {
 238
 239     let env: &BackupEnvironment = rpcenv.as_ref();
 240
 241     let name = tools::required_string_param(&param, "archive-name")?.to_owned();
 242
 243     let archive_name = name.clone();
 244     if !archive_name.ends_with(".didx") {
 245         bail!("wrong archive extension: '{}'", archive_name);
 246     }
 247
 248     let mut path = env.backup_dir.relative_path();
 249     path.push(archive_name);
 250
 251     let index = env.datastore.create_dynamic_writer(&path)?;
 252     let wid = env.register_dynamic_writer(index, name)?;
 253
 254     env.log(format!("created new dynamic index {} ({:?})", wid, path));
 255
 256     Ok(json!(wid))
 257 }
 258
 259 #[sortable]
 260 pub const API_METHOD_CREATE_FIXED_INDEX: ApiMethod = ApiMethod::new(
 261     &ApiHandler::Sync(&create_fixed_index),
 262     &ObjectSchema::new(
 263         "Create fixed chunk index file.",
 264         &sorted!([
 265             ("archive-name", false, &crate::api2::types::BACKUP_ARCHIVE_NAME_SCHEMA),
 266             ("size", false, &IntegerSchema::new("File size.")
 267              .minimum(1)
 268              .schema()
 269             ),
 270         ]),
 271     )
 272 );
 273
 274 fn create_fixed_index(
 275     param: Value,
 276     _info: &ApiMethod,
 277     rpcenv: &mut dyn RpcEnvironment,
 278 ) -> Result<Value, Error> {
 279
 280     let env: &BackupEnvironment = rpcenv.as_ref();
 281
 282     println!("PARAM: {:?}", param);
 283
 284     let name = tools::required_string_param(&param, "archive-name")?.to_owned();
 285     let size = tools::required_integer_param(&param, "size")? as usize;
 286
 287     let archive_name = name.clone();
 288     if !archive_name.ends_with(".fidx") {
 289         bail!("wrong archive extension: '{}'", archive_name);
 290     }
 291
 292     let mut path = env.backup_dir.relative_path();
 293     path.push(archive_name);
 294
 295     let chunk_size = 4096*1024; // todo: ??
 296
 297     let index = env.datastore.create_fixed_writer(&path, size, chunk_size)?;
 298     let wid = env.register_fixed_writer(index, name, size, chunk_size as u32)?;
 299
 300     env.log(format!("created new fixed index {} ({:?})", wid, path));
 301
 302     Ok(json!(wid))
 303 }
 304
 305 #[sortable]
 306 pub const API_METHOD_DYNAMIC_APPEND: ApiMethod = ApiMethod::new(
 307     &ApiHandler::Sync(&dynamic_append),
 308     &ObjectSchema::new(
 309         "Append chunk to dynamic index writer.",
 310         &sorted!([
 311             (
 312                 "wid",
 313                 false,
 314                 &IntegerSchema::new("Dynamic writer ID.")
 315                     .minimum(1)
 316                     .maximum(256)
 317                     .schema()
 318             ),
 319             (
 320                 "digest-list",
 321                 false,
 322                 &ArraySchema::new("Chunk digest list.", &CHUNK_DIGEST_SCHEMA).schema()
 323             ),
 324             (
 325                 "offset-list",
 326                 false,
 327                 &ArraySchema::new(
 328                     "Chunk offset list.",
 329                     &IntegerSchema::new("Corresponding chunk offsets.")
 330                         .minimum(0)
 331                         .schema()
 332                 ).schema()
 333             ),
 334         ]),
 335     )
 336 );
 337
 338 fn dynamic_append (
 339     param: Value,
 340     _info: &ApiMethod,
 341     rpcenv: &mut dyn RpcEnvironment,
 342 ) -> Result<Value, Error> {
 343
 344     let wid = tools::required_integer_param(&param, "wid")? as usize;
 345     let digest_list = tools::required_array_param(&param, "digest-list")?;
 346     let offset_list = tools::required_array_param(&param, "offset-list")?;
 347
 348     if offset_list.len() != digest_list.len() {
 349         bail!("offset list has wrong length ({} != {})", offset_list.len(), digest_list.len());
 350     }
 351
 352     let env: &BackupEnvironment = rpcenv.as_ref();
 353
 354     env.debug(format!("dynamic_append {} chunks", digest_list.len()));
 355
 356     for (i, item) in digest_list.iter().enumerate() {
 357         let digest_str = item.as_str().unwrap();
 358         let digest = proxmox::tools::hex_to_digest(digest_str)?;
 359         let offset = offset_list[i].as_u64().unwrap();
 360         let size = env.lookup_chunk(&digest).ok_or_else(|| format_err!("no such chunk {}", digest_str))?;
 361
 362         env.dynamic_writer_append_chunk(wid, offset, size, &digest)?;
 363
 364         env.debug(format!("sucessfully added chunk {} to dynamic index {} (offset {}, size {})", digest_str, wid, offset, size));
 365     }
 366
 367     Ok(Value::Null)
 368 }
 369
 370 #[sortable]
 371 pub const API_METHOD_FIXED_APPEND: ApiMethod = ApiMethod::new(
 372     &ApiHandler::Sync(&fixed_append),
 373     &ObjectSchema::new(
 374         "Append chunk to fixed index writer.",
 375         &sorted!([
 376             (
 377                 "wid",
 378                 false,
 379                 &IntegerSchema::new("Fixed writer ID.")
 380                     .minimum(1)
 381                     .maximum(256)
 382                     .schema()
 383             ),
 384             (
 385                 "digest-list",
 386                 false,
 387                 &ArraySchema::new("Chunk digest list.", &CHUNK_DIGEST_SCHEMA).schema()
 388             ),
 389             (
 390                 "offset-list",
 391                 false,
 392                 &ArraySchema::new(
 393                     "Chunk offset list.",
 394                     &IntegerSchema::new("Corresponding chunk offsets.")
 395                         .minimum(0)
 396                         .schema()
 397                 ).schema()
 398             )
 399         ]),
 400     )
 401 );
 402
 403 fn fixed_append (
 404     param: Value,
 405     _info: &ApiMethod,
 406     rpcenv: &mut dyn RpcEnvironment,
 407 ) -> Result<Value, Error> {
 408
 409     let wid = tools::required_integer_param(&param, "wid")? as usize;
 410     let digest_list = tools::required_array_param(&param, "digest-list")?;
 411     let offset_list = tools::required_array_param(&param, "offset-list")?;
 412
 413     if offset_list.len() != digest_list.len() {
 414         bail!("offset list has wrong length ({} != {})", offset_list.len(), digest_list.len());
 415     }
 416
 417     let env: &BackupEnvironment = rpcenv.as_ref();
 418
 419     env.debug(format!("fixed_append {} chunks", digest_list.len()));
 420
 421     for (i, item) in digest_list.iter().enumerate() {
 422         let digest_str = item.as_str().unwrap();
 423         let digest = proxmox::tools::hex_to_digest(digest_str)?;
 424         let offset = offset_list[i].as_u64().unwrap();
 425         let size = env.lookup_chunk(&digest).ok_or_else(|| format_err!("no such chunk {}", digest_str))?;
 426
 427         env.fixed_writer_append_chunk(wid, offset, size, &digest)?;
 428
 429         env.debug(format!("sucessfully added chunk {} to fixed index {} (offset {}, size {})", digest_str, wid, offset, size));
 430     }
 431
 432     Ok(Value::Null)
 433 }
 434
 435 #[sortable]
 436 pub const API_METHOD_CLOSE_DYNAMIC_INDEX: ApiMethod = ApiMethod::new(
 437     &ApiHandler::Sync(&close_dynamic_index),
 438     &ObjectSchema::new(
 439         "Close dynamic index writer.",
 440         &sorted!([
 441             (
 442                 "wid",
 443                 false,
 444                 &IntegerSchema::new("Dynamic writer ID.")
 445                     .minimum(1)
 446                     .maximum(256)
 447                     .schema()
 448             ),
 449             (
 450                 "chunk-count",
 451                 false,
 452                 &IntegerSchema::new("Chunk count. This is used to verify that the server got all chunks.")
 453                     .minimum(1)
 454                     .schema()
 455             ),
 456             (
 457                 "size",
 458                 false,
 459                 &IntegerSchema::new("File size. This is used to verify that the server got all data.")
 460                     .minimum(1)
 461                     .schema()
 462             ),
 463             ("csum", false, &StringSchema::new("Digest list checksum.").schema()),
 464         ]),
 465     )
 466 );
 467
 468 fn close_dynamic_index (
 469     param: Value,
 470     _info: &ApiMethod,
 471     rpcenv: &mut dyn RpcEnvironment,
 472 ) -> Result<Value, Error> {
 473
 474     let wid = tools::required_integer_param(&param, "wid")? as usize;
 475     let chunk_count = tools::required_integer_param(&param, "chunk-count")? as u64;
 476     let size = tools::required_integer_param(&param, "size")? as u64;
 477     let csum_str = tools::required_string_param(&param, "csum")?;
 478     let csum = proxmox::tools::hex_to_digest(csum_str)?;
 479
 480     let env: &BackupEnvironment = rpcenv.as_ref();
 481
 482     env.dynamic_writer_close(wid, chunk_count, size, csum)?;
 483
 484     env.log(format!("sucessfully closed dynamic index {}", wid));
 485
 486     Ok(Value::Null)
 487 }
 488
 489 #[sortable]
 490 pub const API_METHOD_CLOSE_FIXED_INDEX: ApiMethod = ApiMethod::new(
 491     &ApiHandler::Sync(&close_fixed_index),
 492     &ObjectSchema::new(
 493         "Close fixed index writer.",
 494         &sorted!([
 495             (
 496                 "wid",
 497                 false,
 498                 &IntegerSchema::new("Fixed writer ID.")
 499                     .minimum(1)
 500                     .maximum(256)
 501                     .schema()
 502             ),
 503             (
 504                 "chunk-count",
 505                 false,
 506                 &IntegerSchema::new("Chunk count. This is used to verify that the server got all chunks.")
 507                     .minimum(1)
 508                     .schema()
 509             ),
 510             (
 511                 "size",
 512                 false,
 513                 &IntegerSchema::new("File size. This is used to verify that the server got all data.")
 514                     .minimum(1)
 515                     .schema()
 516             ),
 517             ("csum", false, &StringSchema::new("Digest list checksum.").schema()),
 518         ]),
 519     )
 520 );
 521
 522 fn close_fixed_index (
 523     param: Value,
 524     _info: &ApiMethod,
 525     rpcenv: &mut dyn RpcEnvironment,
 526 ) -> Result<Value, Error> {
 527
 528     let wid = tools::required_integer_param(&param, "wid")? as usize;
 529     let chunk_count = tools::required_integer_param(&param, "chunk-count")? as u64;
 530     let size = tools::required_integer_param(&param, "size")? as u64;
 531     let csum_str = tools::required_string_param(&param, "csum")?;
 532     let csum = proxmox::tools::hex_to_digest(csum_str)?;
 533
 534     let env: &BackupEnvironment = rpcenv.as_ref();
 535
 536     env.fixed_writer_close(wid, chunk_count, size, csum)?;
 537
 538     env.log(format!("sucessfully closed fixed index {}", wid));
 539
 540     Ok(Value::Null)
 541 }
 542
 543 fn finish_backup (
 544     _param: Value,
 545     _info: &ApiMethod,
 546     rpcenv: &mut dyn RpcEnvironment,
 547 ) -> Result<Value, Error> {
 548
 549     let env: &BackupEnvironment = rpcenv.as_ref();
 550
 551     env.finish_backup()?;
 552     env.log("sucessfully finished backup");
 553
 554     Ok(Value::Null)
 555 }
 556
 557 #[sortable]
 558 pub const API_METHOD_DYNAMIC_CHUNK_INDEX: ApiMethod = ApiMethod::new(
 559     &ApiHandler::AsyncHttp(&dynamic_chunk_index),
 560     &ObjectSchema::new(
 561         r###"
 562 Download the dynamic chunk index from the previous backup.
 563 Simply returns an empty list if this is the first backup.
 564 "### ,
 565         &sorted!([
 566             ("archive-name", false, &crate::api2::types::BACKUP_ARCHIVE_NAME_SCHEMA)
 567         ]),
 568     )
 569 );
 570
 571 fn dynamic_chunk_index(
 572     _parts: Parts,
 573     _req_body: Body,
 574     param: Value,
 575     _info: &ApiMethod,
 576     rpcenv: Box<dyn RpcEnvironment>,
 577 ) -> ApiResponseFuture {
 578
 579     async move {
 580         let env: &BackupEnvironment = rpcenv.as_ref();
 581
 582         let archive_name = tools::required_string_param(&param, "archive-name")?.to_owned();
 583
 584         if !archive_name.ends_with(".didx") {
 585             bail!("wrong archive extension: '{}'", archive_name);
 586         }
 587
 588         let empty_response = {
 589             Response::builder()
 590                 .status(StatusCode::OK)
 591                 .body(Body::empty())?
 592         };
 593
 594         let last_backup = match &env.last_backup {
 595             Some(info) => info,
 596             None => return Ok(empty_response),
 597         };
 598
 599         let mut path = last_backup.backup_dir.relative_path();
 600         path.push(&archive_name);
 601
 602         let index = match env.datastore.open_dynamic_reader(path) {
 603             Ok(index) => index,
 604             Err(_) => {
 605                 env.log(format!("there is no last backup for archive '{}'", archive_name));
 606                 return Ok(empty_response);
 607             }
 608         };
 609
 610         env.log(format!("download last backup index for archive '{}'", archive_name));
 611
 612         let count = index.index_count();
 613         for pos in 0..count {
 614             let (start, end, digest) = index.chunk_info(pos)?;
 615             let size = (end - start) as u32;
 616             env.register_chunk(digest, size)?;
 617         }
 618
 619         let reader = DigestListEncoder::new(Box::new(index));
 620
 621         let stream = WrappedReaderStream::new(reader);
 622
 623         // fixme: set size, content type?
 624         let response = http::Response::builder()
 625             .status(200)
 626             .body(Body::wrap_stream(stream))?;
 627
 628         Ok(response)
 629     }.boxed()
 630 }
 631
 632 #[sortable]
 633 pub const API_METHOD_FIXED_CHUNK_INDEX: ApiMethod = ApiMethod::new(
 634     &ApiHandler::AsyncHttp(&fixed_chunk_index),
 635     &ObjectSchema::new(
 636         r###"
 637 Download the fixed chunk index from the previous backup.
 638 Simply returns an empty list if this is the first backup.
 639 "### ,
 640         &sorted!([
 641             ("archive-name", false, &crate::api2::types::BACKUP_ARCHIVE_NAME_SCHEMA)
 642         ]),
 643     )
 644 );
 645
 646 fn fixed_chunk_index(
 647     _parts: Parts,
 648     _req_body: Body,
 649     param: Value,
 650     _info: &ApiMethod,
 651     rpcenv: Box<dyn RpcEnvironment>,
 652 ) -> ApiResponseFuture {
 653
 654     async move {
 655         let env: &BackupEnvironment = rpcenv.as_ref();
 656
 657         let archive_name = tools::required_string_param(&param, "archive-name")?.to_owned();
 658
 659         if !archive_name.ends_with(".fidx") {
 660             bail!("wrong archive extension: '{}'", archive_name);
 661         }
 662
 663         let empty_response = {
 664             Response::builder()
 665                 .status(StatusCode::OK)
 666                 .body(Body::empty())?
 667         };
 668
 669         let last_backup = match &env.last_backup {
 670             Some(info) => info,
 671             None => return Ok(empty_response),
 672         };
 673
 674         let mut path = last_backup.backup_dir.relative_path();
 675         path.push(&archive_name);
 676
 677         let index = match env.datastore.open_fixed_reader(path) {
 678             Ok(index) => index,
 679             Err(_) => {
 680                 env.log(format!("there is no last backup for archive '{}'", archive_name));
 681                 return Ok(empty_response);
 682             }
 683         };
 684
 685         env.log(format!("download last backup index for archive '{}'", archive_name));
 686
 687         let count = index.index_count();
 688         let image_size = index.index_bytes();
 689         for pos in 0..count {
 690             let digest = index.index_digest(pos).unwrap();
 691             // Note: last chunk can be smaller
 692             let start = (pos*index.chunk_size) as u64;
 693             let mut end = start + index.chunk_size as u64;
 694             if end > image_size { end = image_size; }
 695             let size = (end - start) as u32;
 696             env.register_chunk(*digest, size)?;
 697         }
 698
 699         let reader = DigestListEncoder::new(Box::new(index));
 700
 701         let stream = WrappedReaderStream::new(reader);
 702
 703         // fixme: set size, content type?
 704         let response = http::Response::builder()
 705             .status(200)
 706             .body(Body::wrap_stream(stream))?;
 707
 708         Ok(response)
 709     }.boxed()
 710 }