RUST-1208 Future-proof features

Cargo.toml

@@ -27,46 +27,37 @@ exclude = [
 ]
 
 [features]
-default = []
+default = ["compat-3-0-0", "rustls-tls", "dns-resolver"]
+compat-3-0-0 = []
 sync = []
-openssl-tls = ["openssl", "openssl-probe", "tokio-openssl"]
-
-# Enable support for v0.4 of the chrono crate in the public API of the BSON library.
-bson-chrono-0_4 = ["bson/chrono-0_4"]
-
-# Enable support for the serde_with crate in the BSON library.
-bson-serde_with = ["bson/serde_with"]
-
-# Enable support for v0.8 of the uuid crate in the public API of the BSON library.
-bson-uuid-0_8 = ["bson/uuid-0_8"]
-
-# Enable support for v1.x of the uuid crate in the public API of the BSON library.
-bson-uuid-1 = ["bson/uuid-1"]
+rustls-tls = ["dep:rustls", "dep:rustls-pemfile", "dep:tokio-rustls"]
+openssl-tls = ["dep:openssl", "dep:openssl-probe", "dep:tokio-openssl"]
+dns-resolver = ["dep:trust-dns-resolver", "dep:trust-dns-proto"]
 
 # Enable support for MONGODB-AWS authentication.
 # This can only be used with the tokio-runtime feature flag.
-aws-auth = ["reqwest"]
+aws-auth = ["dep:reqwest"]
 
 # Enable support for on-demand Azure KMS credentials.
 # This can only be used with the tokio-runtime feature flag.
-azure-kms = ["reqwest"]
+azure-kms = ["dep:reqwest"]
 
 # Enable support for on-demand GCP KMS credentials.
 # This can only be used with the tokio-runtime feature flag.
-gcp-kms = ["reqwest"]
+gcp-kms = ["dep:reqwest"]
 
-zstd-compression = ["zstd"]
-zlib-compression = ["flate2"]
-snappy-compression = ["snap"]
+zstd-compression = ["dep:zstd"]
+zlib-compression = ["dep:flate2"]
+snappy-compression = ["dep:snap"]
 
 # Enables support for client-side field level encryption and queryable encryption.
 # The In Use Encryption API is unstable and may have backwards-incompatible changes in minor version updates.
-in-use-encryption-unstable = ["mongocrypt", "rayon", "num_cpus"]
+in-use-encryption-unstable = ["dep:mongocrypt", "dep:rayon", "dep:num_cpus"]
 
 # Enables support for emitting tracing events.
 # The tracing API is unstable and may have backwards-incompatible changes in minor version updates.
 # TODO: pending https://github.com/tokio-rs/tracing/issues/2036 stop depending directly on log.
-tracing-unstable = ["tracing", "log"]
+tracing-unstable = ["dep:tracing", "dep:log"]
 
 [dependencies]
 action_macro = { path = "action_macro" }
@@ -95,7 +86,7 @@ percent-encoding = "2.0.0"
 rand = { version = "0.8.3", features = ["small_rng"] }
 rayon = { version = "1.5.3", optional = true }
 rustc_version_runtime = "0.2.1"
-rustls-pemfile = "1.0.1"
+rustls-pemfile = { version = "1.0.1", optional = true }
 serde_with = "1.3.1"
 sha-1 = "0.10.0"
 sha2 = "0.10.2"
@@ -107,8 +98,8 @@ take_mut = "0.2.2"
 thiserror = "1.0.24"
 tokio-openssl = { version = "0.6.3", optional = true }
 tracing = { version = "0.1.36", optional = true }
-trust-dns-proto = "0.21.2"
-trust-dns-resolver = "0.21.2"
+trust-dns-proto = { version = "0.21.2", optional = true }
+trust-dns-resolver = { version = "0.21.2", optional = true }
 typed-builder = "0.10.0"
 webpki-roots = "0.25.2"
 zstd = { version = "0.11.2", optional = true }
@@ -125,6 +116,7 @@ features = ["json", "rustls-tls"]
 
 [dependencies.rustls]
 version = "0.21.6"
+optional = true
 features = ["dangerous_configuration"]
 
 [dependencies.serde]
@@ -140,6 +132,7 @@ features = ["io-util", "sync", "macros", "net", "process", "rt", "time"]
 
 [dependencies.tokio-rustls]
 version = "0.24.1"
+optional = true
 features = ["dangerous_configuration"]
 
 [dependencies.tokio-util]

README.md

@@ -64,10 +64,6 @@ features = ["sync"]
 |:---------------------|:--------------------------------------------------------------------------------------------------------------------------------------|:--------------------------------|:--------|
 | `sync`               | Expose the synchronous API (`mongodb::sync`).                                                                                         | n/a                             | no      |
 | `aws-auth`           | Enable support for the MONGODB-AWS authentication mechanism.                                                                          | `reqwest`                       | no      |
-| `bson-uuid-0_8`      | Enable support for v0.8 of the [`uuid`](docs.rs/uuid/0.8) crate in the public API of the re-exported `bson` crate.                    | n/a                             | no      |
-| `bson-uuid-1`        | Enable support for v1.x of the [`uuid`](docs.rs/uuid/1.0) crate in the public API of the re-exported `bson` crate.                    | n/a                             | no      |
-| `bson-chrono-0_4`    | Enable support for v0.4 of the [`chrono`](docs.rs/chrono/0.4) crate in the public API of the re-exported `bson` crate.                | n/a                             | no      |
-| `bson-serde_with`    | Enable support for the [`serde_with`](docs.rs/serde_with/latest) crate in the public API of the re-exported `bson` crate.             | `serde_with`                    | no      |
 | `zlib-compression`   | Enable support for compressing messages with [`zlib`](https://zlib.net/)                                                              | `flate2`                        | no      |
 | `zstd-compression`   | Enable support for compressing messages with [`zstd`](http://facebook.github.io/zstd/).                                               | `zstd`                          | no      |
 | `snappy-compression` | Enable support for compressing messages with [`snappy`](http://google.github.io/snappy/)                                              | `snap`                          | no      |

manual/src/installation_features.md

@@ -22,10 +22,6 @@ features = ["sync"]
 |:---------------------|:--------------------------------------------------------------------------------------------------------------------------------------|:------------------------------------|:--------|
 | `sync`               | Expose the synchronous API (`mongodb::sync`).                                                                                         | n/a                                 | no      |
 | `aws-auth`           | Enable support for the MONGODB-AWS authentication mechanism.                                                                          | `reqwest` 0.11                      | no      |
-| `bson-uuid-0_8`      | Enable support for v0.8 of the [`uuid`](docs.rs/uuid/0.8) crate in the public API of the re-exported `bson` crate.                    | n/a                                 | no      |
-| `bson-uuid-1`        | Enable support for v1.x of the [`uuid`](docs.rs/uuid/1.0) crate in the public API of the re-exported `bson` crate.                    | n/a                                 | no      |
-| `bson-chrono-0_4`    | Enable support for v0.4 of the [`chrono`](docs.rs/chrono/0.4) crate in the public API of the re-exported `bson` crate.                | n/a                                 | no      |
-| `bson-serde_with`    | Enable support for the [`serde_with`](docs.rs/serde_with/latest) crate in the public API of the re-exported `bson` crate.             | `serde_with` 1.0                    | no      |
 | `zlib-compression`   | Enable support for compressing messages with [`zlib`](https://zlib.net/)                                                              | `flate2` 1.0                        | no      |
 | `zstd-compression`   | Enable support for compressing messages with [`zstd`](http://facebook.github.io/zstd/).  This flag requires Rust version 1.54.        | `zstd` 0.9.0                        | no      |
 | `snappy-compression` | Enable support for compressing messages with [`snappy`](http://google.github.io/snappy/)                                              | `snap` 1.0.5                        | no      |

src/action/client_options.rs

@@ -95,6 +95,7 @@ pub struct ParseConnectionString {
 impl ParseConnectionString {
     /// In the case that "mongodb+srv" is used, SRV and TXT record lookups will be done using the
     /// provided `ResolverConfig` as part of this method.
+    #[cfg(feature = "dns-resolver")]
     pub fn resolver_config(mut self, value: ResolverConfig) -> Self {
         self.resolver_config = Some(value);
         self

src/client.rs

@@ -478,7 +478,7 @@ impl Client {
         }
     }
 
-    #[cfg(test)]
+    #[cfg(all(test, feature = "dns-resolver"))]
     pub(crate) fn get_hosts(&self) -> Vec<String> {
         let watcher = self.inner.topology.watch();
         let state = watcher.peek_latest();

src/client/options.rs

@@ -5,7 +5,6 @@ mod parse;
 mod resolver_config;
 
 use std::{
-    borrow::Cow,
     cmp::Ordering,
     collections::HashSet,
     convert::TryFrom,
@@ -45,7 +44,10 @@ use crate::{
     srv::{OriginalSrvInfo, SrvResolver},
 };
 
+#[cfg(feature = "dns-resolver")]
 pub use resolver_config::ResolverConfig;
+#[cfg(not(feature = "dns-resolver"))]
+pub(crate) use resolver_config::ResolverConfig;
 
 pub(crate) const DEFAULT_PORT: u16 = 27017;
 
@@ -253,14 +255,16 @@ impl ServerAddress {
         })
     }
 
-    pub(crate) fn host(&self) -> Cow<'_, str> {
+    #[cfg(feature = "dns-resolver")]
+    pub(crate) fn host(&self) -> std::borrow::Cow<'_, str> {
         match self {
-            Self::Tcp { host, .. } => Cow::Borrowed(host.as_str()),
+            Self::Tcp { host, .. } => std::borrow::Cow::Borrowed(host.as_str()),
             #[cfg(unix)]
             Self::Unix { path } => path.to_string_lossy(),
         }
     }
 
+    #[cfg(feature = "dns-resolver")]
     pub(crate) fn port(&self) -> Option<u16> {
         match self {
             Self::Tcp { port, .. } => *port,
@@ -597,6 +601,7 @@ pub struct ClientOptions {
     #[builder(default, setter(skip))]
     #[serde(skip)]
     #[derivative(Debug = "ignore")]
+    #[cfg(feature = "dns-resolver")]
     pub(crate) resolver_config: Option<ResolverConfig>,
 
     /// Control test behavior of the client.
@@ -932,8 +937,7 @@ impl HostInfo {
         Ok(match self {
             Self::HostIdentifiers(hosts) => ResolvedHostInfo::HostIdentifiers(hosts),
             Self::DnsRecord(hostname) => {
-                let mut resolver =
-                    SrvResolver::new(resolver_config.clone().map(|config| config.inner)).await?;
+                let mut resolver = SrvResolver::new(resolver_config.clone()).await?;
                 let config = resolver.resolve_client_options(&hostname).await?;
                 ResolvedHostInfo::DnsRecord { hostname, config }
             }
@@ -1264,6 +1268,17 @@ impl ClientOptions {
             MIN_HEARTBEAT_FREQUENCY
         }
     }
+
+    pub(crate) fn resolver_config(&self) -> Option<&ResolverConfig> {
+        #[cfg(feature = "dns-resolver")]
+        {
+            self.resolver_config.as_ref()
+        }
+        #[cfg(not(feature = "dns-resolver"))]
+        {
+            None
+        }
+    }
 }
 
 /// Splits a string into a section before a given index and a section exclusively after the index.
@@ -1359,6 +1374,13 @@ impl ConnectionString {
                 .into())
             }
         };
+        #[cfg(not(feature = "dns-resolver"))]
+        if srv {
+            return Err(Error::invalid_argument(
+                "mongodb+srv connection strings cannot be used when the 'dns-resolver' feature is \
+                 disabled",
+            ));
+        }
 
         let after_scheme = &s[end_of_scheme + 3..];
 

src/client/options/parse.rs

@@ -19,7 +19,10 @@ impl Action for ParseConnectionString {
             .is_some();
         let host_info = std::mem::take(&mut conn_str.host_info);
         let mut options = ClientOptions::from_connection_string(conn_str);
-        options.resolver_config = self.resolver_config.clone();
+        #[cfg(feature = "dns-resolver")]
+        {
+            options.resolver_config = self.resolver_config.clone();
+        }
 
         let resolved = host_info.resolve(self.resolver_config).await?;
         options.hosts = match resolved {
@@ -146,6 +149,7 @@ impl ClientOptions {
             original_srv_info: None,
             #[cfg(test)]
             original_uri: Some(conn_str.original_uri),
+            #[cfg(feature = "dns-resolver")]
             resolver_config: None,
             server_api: None,
             load_balanced: conn_str.load_balanced,

src/client/options/resolver_config.rs

@@ -1,3 +1,4 @@
+#[cfg(feature = "dns-resolver")]
 use trust_dns_resolver::config::ResolverConfig as TrustDnsResolverConfig;
 
 /// Configuration for the upstream nameservers to use for resolution.
@@ -6,9 +7,11 @@ use trust_dns_resolver::config::ResolverConfig as TrustDnsResolverConfig;
 /// API stability.
 #[derive(Clone, Debug, PartialEq)]
 pub struct ResolverConfig {
+    #[cfg(feature = "dns-resolver")]
     pub(crate) inner: TrustDnsResolverConfig,
 }
 
+#[cfg(feature = "dns-resolver")]
 impl ResolverConfig {
     /// Creates a default configuration, using 1.1.1.1, 1.0.0.1 and 2606:4700:4700::1111,
     /// 2606:4700:4700::1001 (thank you, Cloudflare).

src/error.rs

@@ -267,6 +267,7 @@ impl Error {
         self.labels.insert(label);
     }
 
+    #[cfg(feature = "dns-resolver")]
     pub(crate) fn from_resolve_error(error: trust_dns_resolver::error::ResolveError) -> Self {
         ErrorKind::DnsResolve {
             message: error.to_string(),

src/lib.rs

@@ -35,10 +35,6 @@
 //! |:-----------------------------|:------------------------------------------------------------------------------------------------------------------------------------------------------------------------|:--------|
 //! | `sync`                       | Expose the synchronous API (`mongodb::sync`).                                                                                                                           | no      |
 //! | `aws-auth`                   | Enable support for the MONGODB-AWS authentication mechanism.                                                                                                            | no      |
-//! | `bson-uuid-0_8`              | Enable support for v0.8 of the [`uuid`](docs.rs/uuid/0.8) crate in the public API of the re-exported `bson` crate.                                                      | no      |
-//! | `bson-uuid-1`                | Enable support for v1.x of the [`uuid`](docs.rs/uuid/1.0) crate in the public API of the re-exported `bson` crate.                                                      | no      |
-//! | `bson-chrono-0_4`            | Enable support for v0.4 of the [`chrono`](docs.rs/chrono/0.4) crate in the public API of the re-exported `bson` crate.                                                  | no      |
-//! | `bson-serde_with`            | Enable support for the [`serde_with`](docs.rs/serde_with/latest) crate in the public API of the re-exported `bson` crate.                                               | no      |
 //! | `zlib-compression`           | Enable support for compressing messages with [`zlib`](https://zlib.net/).                                                                                               | no      |
 //! | `zstd-compression`           | Enable support for compressing messages with [`zstd`](http://facebook.github.io/zstd/).                                                                                 | no      |
 //! | `snappy-compression`         | Enable support for compressing messages with [`snappy`](http://google.github.io/snappy/).                                                                               | no      |
@@ -142,9 +138,9 @@
 //! ```
 //!
 //! ### Finding documents in a collection
-//! Results from queries are generally returned via [`Cursor`](struct.Cursor.html), a struct which streams
-//! the results back from the server as requested. The [`Cursor`](struct.Cursor.html) type implements the
-//! [`Stream`](https://docs.rs/futures/latest/futures/stream/trait.Stream.html) trait from
+//! Results from queries are generally returned via [`Cursor`](struct.Cursor.html), a struct which
+//! streams the results back from the server as requested. The [`Cursor`](struct.Cursor.html) type
+//! implements the [`Stream`](https://docs.rs/futures/latest/futures/stream/trait.Stream.html) trait from
 //! the [`futures`](https://crates.io/crates/futures) crate, and in order to access its streaming
 //! functionality you need to import at least one of the
 //! [`StreamExt`](https://docs.rs/futures/latest/futures/stream/trait.StreamExt.html) or
@@ -236,14 +232,14 @@
 //! In async Rust, it is common to implement cancellation and timeouts by dropping a future after a
 //! certain period of time instead of polling it to completion. This is how
 //! [`tokio::time::timeout`](https://docs.rs/tokio/1.10.1/tokio/time/fn.timeout.html) works, for
-//! example. However, doing this with futures returned by the driver can leave the driver's internals in
-//! an inconsistent state, which may lead to unpredictable or incorrect behavior (see RUST-937 for more
-//! details). As such, it is **_highly_** recommended to poll all futures returned from the driver to
-//! completion. In order to still use timeout mechanisms like `tokio::time::timeout` with the driver,
-//! one option is to spawn tasks and time out on their
+//! example. However, doing this with futures returned by the driver can leave the driver's
+//! internals in an inconsistent state, which may lead to unpredictable or incorrect behavior (see
+//! RUST-937 for more details). As such, it is **_highly_** recommended to poll all futures returned
+//! from the driver to completion. In order to still use timeout mechanisms like
+//! `tokio::time::timeout` with the driver, one option is to spawn tasks and time out on their
 //! [`JoinHandle`](https://docs.rs/tokio/1.10.1/tokio/task/struct.JoinHandle.html) futures instead of on
-//! the driver's futures directly. This will ensure the driver's futures will always be completely polled
-//! while also allowing the application to continue in the event of a timeout.
+//! the driver's futures directly. This will ensure the driver's futures will always be completely
+//! polled while also allowing the application to continue in the event of a timeout.
 //!
 //! e.g.
 //! ``` rust
@@ -268,8 +264,8 @@
 //!
 //! ## Minimum supported Rust version (MSRV)
 //!
-//! The MSRV for this crate is currently 1.64.0. This will be rarely be increased, and if it ever is,
-//! it will only happen in a minor or major version release.
+//! The MSRV for this crate is currently 1.64.0. This will be rarely be increased, and if it ever
+//! is, it will only happen in a minor or major version release.
 
 #![warn(missing_docs)]
 #![warn(rustdoc::missing_crate_level_docs)]
@@ -289,7 +285,6 @@
 #![cfg_attr(test, type_length_limit = "80000000")]
 #![doc(html_root_url = "https://docs.rs/mongodb/2.8.0")]
 
-
 #[macro_use]
 pub mod options;
 
@@ -318,8 +313,8 @@ mod index;
 mod operation;
 pub mod results;
 pub(crate) mod runtime;
-mod search_index;
 mod sdam;
+mod search_index;
 mod selection_criteria;
 mod serde_util;
 mod srv;
@@ -344,7 +339,17 @@ pub use crate::{
     gridfs::{GridFsBucket, GridFsDownloadStream, GridFsUploadStream},
 };
 
-pub use {client::session::ClusterTime, coll::Namespace, index::IndexModel, sdam::public::*, search_index::SearchIndexModel};
+pub use client::session::ClusterTime;
+pub use coll::Namespace;
+pub use index::IndexModel;
+pub use sdam::public::*;
+pub use search_index::SearchIndexModel;
 
 /// A boxed future.
-pub type BoxFuture<'a, T> = std::pin::Pin<Box<dyn std::future::Future<Output = T> + Send + 'a>>;
+pub type BoxFuture<'a, T> = std::pin::Pin<Box<dyn std::future::Future<Output = T> + Send + 'a>>;
+
+#[cfg(not(feature = "compat-3-0-0"))]
+compile_error!(
+    "The feature 'compat-3-0-0' must be enabled to ensure forward compatibility with future \
+     versions of this crate."
+);