Changes:
* Remove `RemoteObjectId` concept from remote_storage.
Operate directly on /-separated names instead.
These names are now represented by struct `RemotePath` which was renamed from struct `RelativePath`
* Require remote storage to operate on relative paths for its contents, thus simplifying the way to derive them in pageserver and safekeeper
* Make `IndexPart` to use `String` instead of `RelativePath` for its entries, since those are just the layer names
Despite tests working, on staging the library started to fail with the
following error:
```
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 2022-11-16T11:53:37.191211Z INFO init_tenant_mgr:local_tenant_timeline_files: Collected files for 16 tenants
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: thread 'main' panicked at 'A connector was not available. Either set a custom connector or enable the `rustls` and `native-tls` crate featu>
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: stack backtrace:
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 0: rust_begin_unwind
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /rustc/e092d0b6b43f2de967af0887873151bb1c0b18d3/library/std/src/panicking.rs:584:5
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 1: core::panicking::panic_fmt
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /rustc/e092d0b6b43f2de967af0887873151bb1c0b18d3/library/core/src/panicking.rs:142:14
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 2: core::panicking::panic_display
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /rustc/e092d0b6b43f2de967af0887873151bb1c0b18d3/library/core/src/panicking.rs:72:5
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 3: core::panicking::panic_str
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /rustc/e092d0b6b43f2de967af0887873151bb1c0b18d3/library/core/src/panicking.rs:56:5
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 4: core::option::expect_failed
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /rustc/e092d0b6b43f2de967af0887873151bb1c0b18d3/library/core/src/option.rs:1854:5
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 5: <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 6: <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 7: <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 8: <aws_types::credentials::provider::future::ProvideCredentials as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 9: <tracing::instrument::Instrumented<T> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 10: <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 11: <aws_types::credentials::provider::future::ProvideCredentials as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 12: <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 13: <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 14: <aws_smithy_http_tower::map_request::MapRequestFuture<F,E> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 15: <core::pin::Pin<P> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /rustc/e092d0b6b43f2de967af0887873151bb1c0b18d3/library/core/src/future/future.rs:124:9
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 16: <aws_smithy_http_tower::parse_response::ParseResponseService<InnerService,ResponseHandler,RetryPolicy> as tower_service::Service<aws_>
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /home/nonroot/.cargo/registry/src/github.com-1ecc6299db9ec823/aws-smithy-http-tower-0.51.0/src/parse_response.rs:109:34
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 17: <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /rustc/e092d0b6b43f2de967af0887873151bb1c0b18d3/library/core/src/future/mod.rs:91:19
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 18: <tracing::instrument::Instrumented<T> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /home/nonroot/.cargo/registry/src/github.com-1ecc6299db9ec823/tracing-0.1.37/src/instrument.rs:272:9
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 19: <core::pin::Pin<P> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /rustc/e092d0b6b43f2de967af0887873151bb1c0b18d3/library/core/src/future/future.rs:124:9
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 20: <aws_smithy_client::timeout::TimeoutServiceFuture<InnerFuture> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /home/nonroot/.cargo/registry/src/github.com-1ecc6299db9ec823/aws-smithy-client-0.51.0/src/timeout.rs:189:70
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 21: <tower::retry::future::ResponseFuture<P,S,Request> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /home/nonroot/.cargo/registry/src/github.com-1ecc6299db9ec823/tower-0.4.13/src/retry/future.rs:77:41
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 22: <aws_smithy_client::timeout::TimeoutServiceFuture<InnerFuture> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /home/nonroot/.cargo/registry/src/github.com-1ecc6299db9ec823/aws-smithy-client-0.51.0/src/timeout.rs:189:70
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 23: aws_smithy_client::Client<C,M,R>::call_raw::{{closure}}
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /home/nonroot/.cargo/registry/src/github.com-1ecc6299db9ec823/aws-smithy-client-0.51.0/src/lib.rs:227:56
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 24: <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /rustc/e092d0b6b43f2de967af0887873151bb1c0b18d3/library/core/src/future/mod.rs:91:19
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 25: aws_smithy_client::Client<C,M,R>::call::{{closure}}
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /home/nonroot/.cargo/registry/src/github.com-1ecc6299db9ec823/aws-smithy-client-0.51.0/src/lib.rs:184:29
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 26: <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /rustc/e092d0b6b43f2de967af0887873151bb1c0b18d3/library/core/src/future/mod.rs:91:19
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 27: aws_sdk_s3::client::fluent_builders::GetObject::send::{{closure}}
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /home/nonroot/.cargo/registry/src/github.com-1ecc6299db9ec823/aws-sdk-s3-0.21.0/src/client.rs:7735:40
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 28: <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /rustc/e092d0b6b43f2de967af0887873151bb1c0b18d3/library/core/src/future/mod.rs:91:19
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 29: remote_storage::s3_bucket::S3Bucket::download_object::{{closure}}
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at libs/remote_storage/src/s3_bucket.rs:205:20
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 30: <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /rustc/e092d0b6b43f2de967af0887873151bb1c0b18d3/library/core/src/future/mod.rs:91:19
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 31: <remote_storage::s3_bucket::S3Bucket as remote_storage::RemoteStorage>::download::{{closure}}
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at libs/remote_storage/src/s3_bucket.rs:399:11
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 32: <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /rustc/e092d0b6b43f2de967af0887873151bb1c0b18d3/library/core/src/future/mod.rs:91:19
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 33: <core::pin::Pin<P> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /rustc/e092d0b6b43f2de967af0887873151bb1c0b18d3/library/core/src/future/future.rs:124:9
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 34: remote_storage::GenericRemoteStorage::download_storage_object::{{closure}}
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at libs/remote_storage/src/lib.rs:264:55
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 35: <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /rustc/e092d0b6b43f2de967af0887873151bb1c0b18d3/library/core/src/future/mod.rs:91:19
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 36: pageserver::storage_sync::download::download_index_part::{{closure}}
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at pageserver/src/storage_sync/download.rs:148:57
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 37: <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /rustc/e092d0b6b43f2de967af0887873151bb1c0b18d3/library/core/src/future/mod.rs:91:19
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 38: pageserver::storage_sync::download::download_index_parts::{{closure}}::{{closure}}::{{closure}}
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at pageserver/src/storage_sync/download.rs:77:75
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 39: <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /rustc/e092d0b6b43f2de967af0887873151bb1c0b18d3/library/core/src/future/mod.rs:91:19
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 40: <futures_util::stream::futures_unordered::FuturesUnordered<Fut> as futures_core::stream::Stream>::poll_next
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /home/nonroot/.cargo/registry/src/github.com-1ecc6299db9ec823/futures-util-0.3.24/src/stream/futures_unordered/mod.rs:514:17
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 41: futures_util::stream::stream::StreamExt::poll_next_unpin
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /home/nonroot/.cargo/registry/src/github.com-1ecc6299db9ec823/futures-util-0.3.24/src/stream/stream/mod.rs:1626:9
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 42: <futures_util::stream::stream::next::Next<St> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /home/nonroot/.cargo/registry/src/github.com-1ecc6299db9ec823/futures-util-0.3.24/src/stream/stream/next.rs:32:9
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 43: pageserver::storage_sync::download::download_index_parts::{{closure}}
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at pageserver/src/storage_sync/download.rs:80:69
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 44: <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /rustc/e092d0b6b43f2de967af0887873151bb1c0b18d3/library/core/src/future/mod.rs:91:19
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 45: tokio::park:🧵:CachedParkThread::block_on::{{closure}}
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /home/nonroot/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-1.21.1/src/park/thread.rs:267:54
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 46: tokio::coop::with_budget::{{closure}}
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /home/nonroot/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-1.21.1/src/coop.rs:102:9
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 47: std:🧵:local::LocalKey<T>::try_with
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /rustc/e092d0b6b43f2de967af0887873151bb1c0b18d3/library/std/src/thread/local.rs:445:16
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 48: std:🧵:local::LocalKey<T>::with
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /rustc/e092d0b6b43f2de967af0887873151bb1c0b18d3/library/std/src/thread/local.rs:421:9
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 49: tokio::coop::with_budget
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /home/nonroot/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-1.21.1/src/coop.rs:95:5
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 50: tokio::coop::budget
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /home/nonroot/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-1.21.1/src/coop.rs:72:5
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 51: tokio::park:🧵:CachedParkThread::block_on
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /home/nonroot/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-1.21.1/src/park/thread.rs:267:31
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 52: tokio::runtime::enter::Enter::block_on
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /home/nonroot/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-1.21.1/src/runtime/enter.rs:152:13
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 53: tokio::runtime::scheduler::multi_thread::MultiThread::block_on
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /home/nonroot/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-1.21.1/src/runtime/scheduler/multi_thread/mod.rs:79:9
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 54: tokio::runtime::Runtime::block_on
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /home/nonroot/.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-1.21.1/src/runtime/mod.rs:492:44
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 55: pageserver::storage_sync::spawn_storage_sync_task
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at pageserver/src/storage_sync.rs:656:34
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 56: pageserver::tenant_mgr::init_tenant_mgr
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at pageserver/src/tenant_mgr.rs:88:13
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 57: pageserver::start_pageserver
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at pageserver/src/bin/pageserver.rs:269:9
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 58: pageserver::main
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at pageserver/src/bin/pageserver.rs:103:5
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: 59: core::ops::function::FnOnce::call_once
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: at /rustc/e092d0b6b43f2de967af0887873151bb1c0b18d3/library/core/src/ops/function.rs:248:5
Nov 16 11:53:37 pageserver-0.us-east-2.aws.neon.build pageserver[481974]: note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
```
Feels like better testing on the env is needed later, maybe more e2e
tests have to be written (albeit we have download tests, so something
else happens here, tls issues?)
Part of https://github.com/neondatabase/neon/pull/2239
Regular, from scratch, timeline creation involves initdb to be run in a separate directory, data from this directory to be imported into pageserver and, finally, timeline-related background tasks to start.
This PR ensures we don't leave behind any directories that are not marked as temporary and that pageserver removes such directories on restart, allowing timeline creation to be retried with the same IDs, if needed.
It would be good to later rewrite the logic to use a temporary directory, similar what tenant creation does.
Yet currently it's harder than this change, so not done.
* etcd-client is not updated, since we plan to replace it with another client and the new version errors with some missing prost library error
* clap had released another major update that requires changing every CLI declaration again, deserves a separate PR
We had a pattern like this:
match remote_storage {
GenericRemoteStorage::Local(storage) => {
let source = storage.remote_object_id(&file_path)?;
...
storage
.function(&source, ...)
.await
},
GenericRemoteStorage::S3(storage) => {
... exact same code as for the Local case ...
},
This removes the code duplication, by allowing you to call the functions
directly on GenericRemoteStorage.
Also change RemoveObjectId to be just a type alias for String. Now that
the callers of GenericRemoteStorage functions don't know whether they're
dealing with the LocalFs or S3 implementation, RemoveObjectId must be the
same type for both.
The code correctly detected too short and too long inputs, but the error
message was bogus for the case the input stream was too long:
Error: Provided stream has actual size 5 fthat is smaller than the given stream size 4
That check was only supposed to check for too small inputs, but it in
fact caught too long inputs too. That was good, because the check
below that that was supposed to check for too long inputs was in fact
broken, and never did anything. It tried to read input a buffer of
size 0, to check if there is any extra data, but reading to a
zero-sized buffer always returns 0.
download operations of all timelines for one tenant are now grouped
together so when attach is invoked pageserver downloads all of them
and registers them in a single apply_sync_status_update call so
branches can be used safely with attach/detach
Separate task is launched for each timeline and stopped when timeline doesn't
need offloading. Decision who offloads is done through etcd leader election;
currently there is no pre condition for participating, that's a TODO.
neon_local and tests infrastructure for remote storage in safekeepers added,
along with the test itself.
ref #1009
Co-authored-by: Anton Shyrabokau <ahtoxa@Antons-MacBook-Pro.local>