Rework the `Store` hierarchy so that there's now one hierarchy for the
store configs and one for the implementations (where each implementation
extends the corresponding config). So a class hierarchy like
```
StoreConfig-------->Store
| |
v v
SubStoreConfig----->SubStore
| |
v v
SubSubStoreConfig-->SubSubStore
```
(with virtual inheritance to prevent DDD).
The advantage of this architecture is that we can now introspect the configuration of a store without having to instantiate the store itself
Add a new `init()` method to the `Store` class that is supposed to
handle all the effectful initialisation needed to set-up the store.
The constructor should remain side-effect free and just initialize the
c++ data structure.
The goal behind that is that we can create “dummy” instances of each
store to query static properties about it (the parameters it accepts for
example)
Directly register the store classes rather than a function to build an
instance of them.
This gives the possibility to introspect static members of the class or
choose different ways of instantiating them.
istream->tellg() returns -1 so we can't get the number of bytes
written.
Fixes 'uploaded 's3://nix-cache/nar/00819r9lp5kajr6baxfw5dhhc0cx8ndxaz43qmd2f0gn1hk1ynlp.nar.xz' (-1 bytes) in 11620 ms' messages.
This allows overriding the priority of substituters, e.g.
$ nix-store --store ~/my-nix/ -r /nix/store/df3m4da96d84ljzxx4mygfshm1p0r2n3-geeqie-1.4 \
--substituters 'http://cache.nixos.org?priority=100 daemon?priority=10'
Fixes#3264.
Most functions now take a StorePath argument rather than a Path (which
is just an alias for std::string). The StorePath constructor ensures
that the path is syntactically correct (i.e. it looks like
<store-dir>/<base32-hash>-<name>). Similarly, functions like
buildPaths() now take a StorePathWithOutputs, rather than abusing Path
by adding a '!<outputs>' suffix.
Note that the StorePath type is implemented in Rust. This involves
some hackery to allow Rust values to be used directly in C++, via a
helper type whose destructor calls the Rust type's drop()
function. The main issue is the dynamic nature of C++ move semantics:
after we have moved a Rust value, we should not call the drop function
on the original value. So when we move a value, we set the original
value to bitwise zero, and the destructor only calls drop() if the
value is not bitwise zero. This should be sufficient for most types.
Also lots of minor cleanups to the C++ API to make it more modern
(e.g. using std::optional and std::string_view in some places).
This enables using for http for S3 request for debugging or
implementations that don't have https configured. This is not a problem
for binary caches since they should not contain sensitive information.
Both package signatures and AWS auth already protect against tampering.
The use of TransferManager has several issues, including that it
doesn't allow setting a Content-Encoding without a patch, and it
doesn't handle exceptions in worker threads (causing termination on
memory allocation failure).
Fixes#2493.
This meant that making a typo in an s3:// URI would cause a bucket to
be created. Also it didn't handle eventual consistency very well. Now
it's up to the user to create the bucket.
TransferManager allocates a lot of memory (50 MiB by default), and it
might leak but I'm not sure about that. In any case it was causing
OOMs in hydra-queue-runner. So allocate only one TransferManager per
S3BinaryCacheStore.
Hopefully fixes https://github.com/NixOS/hydra/issues/586.
This callback is executed on a different thread, so exceptions thrown
from the callback are not caught:
Aug 08 16:25:48 chef hydra-queue-runner[11967]: terminate called after throwing an instance of 'nix::Error'
Aug 08 16:25:48 chef hydra-queue-runner[11967]: what(): AWS error: failed to upload 's3://nix-cache/19dbddlfb0vp68g68y19p9fswrgl0bg7.ls'
Therefore, just check the transfer status after it completes. Also
include the S3 error message in the exception.
This didn't work anymore since decompression was only done in the
non-coroutine case.
Decompressors are now sinks, just like compressors.
Also fixed a bug in bzip2 API handling (we have to handle BZ_RUN_OK
rather than BZ_OK), which we didn't notice because there was a missing
'throw':
if (ret != BZ_OK)
CompressionError("error while compressing bzip2 file");
This reduces memory consumption of
nix copy --from file://... --to ~/my-nix /nix/store/95cwv4q54dc6giaqv6q6p4r02ia2km35-blender-2.79
from 514 MiB to 18 MiB for an uncompressed binary cache, and from 192
MiB to 53 MiB for a bzipped binary cache. It may also be faster
because fetching can happen concurrently with decompression/writing.
Continuation of 48662d151b.
Issue https://github.com/NixOS/nix/issues/1681.
This allows specifying the AWS configuration profile to use. E.g.
nix copy --from s3://my-cache?profile=aws-dev-account /nix/store/cf3isrlqavvd5w7rpky1fa8j9lcnlggm-...
As far as we're concerned, not being able to access a file just means
the file is missing. Plus, AWS explicitly goes out of its way to
return a 403 if the file is missing and the requester doesn't have
permission to list the bucket.
Also getting rid of an old hack that Eelco said was only relevant
to an older AWS SDK.
Recently aws-sdk-cpp quietly switched to using S3 virtual host URIs
(https://github.com/aws/aws-sdk-cpp/commit/69d9c53882), i.e. it sends
requests to http://<bucket>.<region>.s3.amazonaws.com rather than
http://<region>.s3.amazonaws.com/<bucket>. However this interacts
badly with curl connection reuse. For example, if we do the following:
1) Check whether a bucket exists using GetBucketLocation.
2) If it doesn't, create it using CreateBucket.
3) Do operations on the bucket.
then 3) will fail for a minute or so with a NoSuchBucket exception,
presumably because the server being hit is a fallback for cases when
buckets don't exist.
Disabling the use of virtual hosts ensures that 3) succeeds
immediately. (I don't know what S3's consistency guarantees are for
bucket creation, but in practice buckets appear to be available
immediately.)
