This crate no longer has any reason to exist. All its remaining
functionality is generic enough to go into tor-config.
In this commit, we move the contents of lib.rs into a new file in
tor-config. It contains:
* Code motion
* The minimal "mod" and "use" changes
* The minimal doc comment
* A new a compat alias for ConfigurationSources.
The compat alias is there because various crates currently speak of
arti_config::ConfigurationSources and it is most convenient to fix
them up after the type is available in tor_config.
Test the Deserialize impl of every config struct.
This detects bugs like the one fixed in !502.
The macro now becomes more complex because it needs to take options.
Right now this tt-munching option parser is overkill, but this
leave space for further options in the future.
I have Plans for this macro. In particular:
* I have a wip branch which tests that the Builder can be
deserialised from an empty config (ie, that config reading
of a config with a blank section for this item works).
* I think we should autogenerate $Config::builder(),
and promote that, rather than $ConfigBuilder::default().
This macro could do that.
For reference, the git source for this crate (and the others in its
workspace) currently lives in my personal github account (ijackson).
If this fork turns out to be long-lived and gains features and/or
users, it would be good to move it to a gitlab somewhere.
I have granted Nick crate ownership on the crates.io system.
* Builders additionally derive: Debug, Serialize, Deserialize.
* Validated structs no longer derive: Serialize, Deserialize
and all related attributes deleted.
* As a consequence, all the `#[serde(deny_unknown_fields)]`
are gone. That means that right now unknown fields are totally
ignored. This is good for compatibility but poor for useability.
Doing something better here is arti#417, in progress.
* As a consequence, delete tor_dirmgr::retry::default_parallelism.
(The default value was already duplicated into a builder attr.)
This allows us to use this with an item builder type which doesn't
impl Default. (Obviously this only makes sense for items which aren't
actually builders.)
It is Quite Vexing that we have to use [ ] rather than the < > around
the generics, particularly given that we are also using [ ] to signal
"this is arrayish".
Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
The new API is (roughly) as discussed in
https://gitlab.torproject.org/tpo/core/arti/-/issues/451
This is quite a large commit and it is not convenient to split it up.
It contains the following changes:
* Redo the list builder and accessor macros implemnetation,
including docs and tests.
* Change uses of define_list_config_builder. In each case:
- Move the docs about the default value to the containing field.
- Remove the other docs (which were just recapitulations, and
are now not needed since the ListBuilder is no longer public).
- Rewmove or replace `pub` in the define_list_builder_helper call,
so that the builder is no longer public.
- Change the main macro call site to use define_list_builder_helper.
- Add a call to define_list_builder_accessors.
* Make the module `list_builder` pub so that we have somewhere to
put the overview documentation.
* Consequential changes:
- Change `outer.inner().replace(X)` to `outer.set_inner(X)`
- Consequential changes to imports (`use` statements).
Document that this can contain either a string for expansion, or a
literal PathBuf not for expansion.
Rename the `from_path` method to `new_literal`: a very important
difference is whether it gets expanded - less important than the Rust
type. Also, now it takes `Into<PathBuf>`, which avoids a needless
clone.
(We don't change the API in `arti-client` because
`&tempfile::Tempdir()` doesn't implement `Into<PathBuf>`, so
`arti-client` has to have some new `as_ref` calls.)
Provide accessors `as_unexpanded_str` and `as_literal_path`. The
deserialisation already makes this part of the stable API,l so not
pvoding accessors seems just obstructive. They are useful for tests,
too.
Add tests for the new entrypoints, and for deserialisation of both
variants from TOML (via config, or directly) and JSON.
We introduce LiteralPath struct, so that a literal path deserialises
from
some_path = { literal: "actual path string" }
This makes the deserialisation unambiguous.
The `[patch]` approach causes the tree not to build when used as a
dependency, unless the `[patch]` is replicated into the depending
project.
Instead, replace our `derive_builer =` dependencies with a reference
to a specific git commit:
perl -i~ -pe 'next unless m/^derive_builder/; s#"(0\.11\.2)"#{ version = "$1", git = "https://github.com/ijackson/rust-derive-builder", rev = "ba0c1a5311bd9f93ddf5f5b8ec2a5f6f03b22fbe" }#' crates/*/Cargo.toml
Note that the commitid has changed. This is because derive_builder is
in fact a workspace of 4 crates. 3 of them are of interest to arti
itself (the 4th exists only for testing). So the same "add git
revision" treatment had to be done to the `derive_builder` and
`derive_builder_macro` crates. Each dependency edge involves a new
commit in the derive_builder workspace, since we can't create a git
commit containing its own commitid. (We want to use commits, rather
than a branch, so that what we are depending on is actually properly
defined, and not subject to the whims of my personal github
namespace.)
There are no actual code changes in derive_builder.
Really, we probably don't want any of these not to be pub, but it
triggers "unreachable pub" in my test cases, and making it not pub by
mistake seems not very serious, and likely to be noticed.
Making the struct private in the test cases has the useful effect of
checking that all the methods are tested.
And add an imprecation in define_list_config_builder's doc comment do
do so in future for other invocations of the macro.
Add add the missing full stops.
This is an automated change made with a perl one-liner and verified
with grep -L and grep -l.
Some warnings are introduced with this change; they will be removed
in subsequent commits.
See arti#208 for older discussion on this issue.
This commitid is the current head of my MR branch
https://github.com/colin-kiegel/rust-derive-builder/pull/253https://github.com/ijackson/rust-derive-builder/tree/field-builder
Using the commitid prevents surprises if that branch is updated.
We will require this newer version of derive_builder. The version
will need to be bumped again later, assuming the upstream MR is merged
and upstream do a release containing the needed changes.
We will need the new version of not only `derive_builder_core` (the
main macro implementation) but also`derive_builder` for a new error
type.
Not all of these strictly need to be bumped to 0.2.0; many could go
to 0.1.1 instead. But since everything at the tor-rtcompat and
higher layers has had breaking API changes, it seems not so useful
to distinguish. (It seems unlikely that anybody at this stage is
depending on e.g. tor-protover but not arti-client.)
This has the different syntax for builder field attributes than what I
originally proposed in my MR, and which therefore is in the pinned
branch.
My upstream MR for the field attributes feature was morged:
https://github.com/colin-kiegel/rust-derive-builder/issues/239
We are going to want to specify custom attributes on fields of the
builder struct. This feature was missing from derive_builder.
This commitid is the current head of my MR branch
https://github.com/colin-kiegel/rust-derive-builder/pull/237https://github.com/ijackson/rust-derive-builder/tree/builder-field-attrs
Using the commitid prevents surprises if that branch is updated.
We will require this newer version of derive_builder. The version
will need to be bumped again later, assuming the upstream MR is merged
and upstream do a release containing the needed changes.
This lint is IMO inherently ill-conceived.
I have looked for the reasons why this might be thought to be a good
idea and there were basically two (and they are sort of contradictory):
I. "Calling ‘.clone()` on an Rc, Arc, or Weak can obscure the fact
that only the pointer is being cloned, not the underlying data."
This is the wording from
https://rust-lang.github.io/rust-clippy/v0.0.212/#clone_on_ref_ptr
It is a bit terse; we are left to infer why it is a bad idea to
obscure this fact. It seems to me that if it is bad to obscure some
fact, that must be because the fact is a hazard. But why would it be
a hazard to not copy the underlying data ?
In other languages, faliing to copy the underlying data is a serious
correctness hazard. There is a whose class of bugs where things were
not copied, and then mutated and/or reused in multiple places in ways
that were not what the programmer intended. In my experience, this is
a very common bug when writing Python and Javascript. I'm told it's
common in golang too.
But in Rust this bug is much much harder to write. The data inside an
Arc is immutable. To have this bug you'd have use interior mutability
- ie mess around with Mutex or RefCell. That provides a good barrier
to these kind of accidents.
II. "The reason for writing Rc::clone and Arc::clone [is] to make it
clear that only the pointer is being cloned, as opposed to the
underlying data. The former is always fast, while the latter can
be very expensive depending on what is being cloned."
This is the reasoning found here
https://github.com/rust-lang/rust-clippy/issues/2048
This is saying that *not* using Arc::clone is hazardous.
Specifically, that a deep clone is a performance hazard.
But for this argument, the lint is precisely backwards. It's linting
the "good" case and asking for it to be written in a more explicit
way; while the supposedly bad case can be written conveniently.
Also, many objects (in our codebase, and in all the libraries we use)
that are Clone are in fact simply handles. They contain Arc(s) (or
similar) and are cheap to clone. Indeed, that is the usual case.
It does not make sense to distinguish in the syntax we use to clone
such a handle, whether the handle is a transparent Arc, or an opaque
struct containing one or more other handles.
Forcing Arc::clone to be written as such makes for code churn when a
type is changed from Arc<Something> to Something: Clone, or vice
versa.
I found these versions empirically, by using the following process:
First, I used `cargo tree --depth 1 --kind all` to get a list of
every immediate dependency we had.
Then, I used `cargo upgrade --workspace package@version` to change
each dependency to the earliest version with which (in theory) the
current version is semver-compatible. IOW, if the current version
was 3.2.3, I picked "3". If the current version was 0.12.8, I
picked "0.12".
Then, I used `cargo +nightly upgrade -Z minimal-versions` to
downgrade Cargo.lock to the minimal listed version for each
dependency. (I had to override a few packages; see .gitlab-ci.yml
for details).
Finally, I repeatedly increased the version of each of our
dependencies until our code compiled and the tests passed. Here's
what I found that we need:
anyhow >= 1.0.5: Earlier versions break our hyper example.
async-broadcast >= 0.3.2: Earlier versions fail our tests.
async-compression 0.3.5: Earlier versions handled futures and tokio
differently.
async-trait >= 0.1.2: Earlier versions are too buggy to compile our
code.
clap 2.33.0: For Arg::default_value_os().
coarsetime >= 0.1.20: exposed as_ticks() function.
curve25519-dalek >= 3.2: For is_identity().
generic-array 0.14.3: Earlier versions don't implement
From<&[T; 32]>
httparse >= 1.2: Earlier versions didn't implement Error.
itertools at 0.10.1: For at_most_once.
rusqlite >= 0.26.3: for backward compatibility with older rustc.
serde 1.0.103: Older versions break our code.
serde_json >= 1.0.50: Since we need its Value type to implement Eq.
shellexpand >= 2.1: To avoid a broken dirs crate version.
tokio >= 1.4: For Handle::block_on().
tracing >= 0.1.18: Previously, tracing_core and tracing had separate
LevelFilter types.
typenum >= 1.12: Compatibility with rust-crypto crates
x25519-dalek >= 1.2.0: For was_contributory().
Closes#275.
We don't want MutCfg to be automatially coneable, or we'll wind up with
surprises like the one that this patch fixes in TorClient.
(The "surprise" is that reconfigure() would only apply its
client-specific options to one client instance.)
It's useful to keep configuration objects inside a RwLock<Arc<>>, so we
can have slightly-stale pointers to the existing configuration structure
without holding locks too long.
This code adds a MutCfg type with basic support for this pattern,
and functions to make it a bit more ergonomic.
This patch doesn't actually make anything reconfigurable, but it
does create an API that will tell you "you can't change the value of
that!" If the API looks reasonable, I can start making it possible
to change the values of individual items.
The sane_defaults() call is now the same as you get from a default
builder: by convention, we just call that method Default::default().
The with_directories() constructor makes more sense as a constructor
for the TorClientConfigBuilder than for TorClientConfig.
Since these shell-variables are hardwired to use org.torproject.Arti as
the program name, it isn't appropriate to call them "app-specific".
If we someday reinstate APP_FOO, it should be based on a user-provided
application name.
In order to handle explicitly specified path buffers directly, we now
let CfgPath be either a string (that gets expanded) or a PathBuf
(that doesn't).
This simplifies TorClientConfig::with_directories()
Now every section that the two configuration objects share has the
same type and name. This should help us in documenting our configuration
in a way that doesn't confuse people.
There is still lots of API work to go.
To do this at all neatly, I had to split out `tor-config` from
`arti-config` again, and putting the lower level stuff (paths,
builder errors) into tor-config. I also changed our use of
derive_builder to always use a common error type, to avoid
error type proliferation.
This switches out `arti`'s argument-parsing library with `clap`, which
is a lot more featureful (and very widely used within the Rust
ecosystem). We also now use a lot of `clap`'s features to improve the
CLI experience:
- The CLI now expects a subcommand (currently, either "help", or "proxy"
for the existing SOCKS proxy behaviour). This should let us add
additional non-SOCKS-proxy features to arti in future.
- `clap` supports default values determined at runtime, so the way the
default config file is loaded was changed: now, we determine the
OS-specific path for said file before invoking `clap`, so the help
command can show it properly.
- The behaviour of `tor_config` was also changed; now, one simply
specifies a list of configuration files to load, together with
whether they're required.
- That function also way overused generics; this has been fixed.
- Instead of using the ARTI_LOG environment variable to configure
logging, one now uses the `-l, --log-level` CLI option.
(The intent is for this option to be more discoverable by users.)
- The `proxy` subcommand allows the user to override the SOCKS port used
on the CLI without editing the config file.
Nick Mathewson
Ian Jackson
eta
Ian Jackson
Michael
Daniel Eades