feat: add optional time backend support with chrono and time crates

.github/workflows/rust.yml

@@ -16,8 +16,11 @@ permissions:
   contents: read
 jobs:
   default-features:
-    name: Default Features (batteries_included + v4)
+    name: Default Features (batteries_included + v4 + (${{ matrix.backend }}))
     runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        backend: [time, chrono]
     steps:
       - uses: actions/checkout@v2
       - uses: actions-rs/toolchain@v1
@@ -28,13 +31,10 @@ jobs:
           components: clippy
       - name: Install nextest
         uses: taiki-e/install-action@nextest
-      - name: Clippy (default features)
-        uses: actions-rs/cargo@v1
-        with:
-          command: clippy
-          args: -- -D warnings
-      - name: Test (default features)
-        run: cargo nextest run
+      - name: Clippy (default features + ${{ matrix.backend }})
+        run: cargo clippy --features ${{ matrix.backend }} -- -D warnings
+      - name: Test (default features + ${{ matrix.backend }})
+        run: cargo nextest run --features ${{ matrix.backend }}
   test:
     name: Test Suite
     runs-on: ubuntu-latest
@@ -58,8 +58,10 @@ jobs:
           override: true
       - name: Install nextest
         uses: taiki-e/install-action@nextest
-      - name: Run tests
-        run: cargo nextest run --no-default-features --features ${{ matrix.feature }}
+      - name: Run tests (time)
+        run: cargo nextest run --no-default-features --features ${{ matrix.feature }},time
+      - name: Run tests (chrono)
+        run: cargo nextest run --no-default-features --features ${{ matrix.feature }},chrono
   clippy:
     name: Clippy
     runs-on: ubuntu-latest
@@ -82,10 +84,16 @@ jobs:
           toolchain: stable
           override: true
           components: clippy
-      - uses: actions-rs/cargo@v1
+      - name: Clippy (time)
+        uses: actions-rs/cargo@v1
+        with:
+          command: clippy
+          args: --no-default-features --features ${{ matrix.feature }},time -- -D warnings
+      - name: Clippy (chrono)
+        uses: actions-rs/cargo@v1
         with:
           command: clippy
-          args: --no-default-features --features ${{ matrix.feature }} -- -D warnings
+          args: --no-default-features --features ${{ matrix.feature }},chrono -- -D warnings
   audit:
     name: Security Audit
     runs-on: ubuntu-latest

Cargo.toml

@@ -51,6 +51,9 @@ v4_public = ["v4", "public", "core", "ed25519-dalek", "ring/std"]
 core = []
 generic = ["core", "serde", "erased-serde", "serde_json"]
 batteries_included = ["generic"]
+# Time backend features (mutually exclusive)
+time = ["dep:time"]
+chrono = ["dep:chrono"]
 default = ["batteries_included", "v4_local", "v4_public"]
 paserk = ["dep:paserk"]
 
@@ -78,7 +81,8 @@ hmac = { version = "0.12", optional = true }
 sha2 = { version = "0.10", optional = true }
 subtle = "2.6"
 zeroize = { version = "1.8", features = ["zeroize_derive"] }
-time = { version = "0.3.47", features = ["parsing", "formatting"] }
+time = { version = "0.3.47", features = ["parsing", "formatting"], optional = true }
+chrono = { version = "0.4", features = ["std"], optional = true }
 rand_core = "0.9"
 digest = "0.10"
 paserk = { version = "0.4.0", optional = true }

src/error.rs

@@ -136,8 +136,14 @@ pub enum Error {
 
     // ==================== Time Format Errors ====================
     /// Error formatting time values
+    #[cfg(feature = "time")]
     #[error("time format error: {0}")]
     TimeFormat(#[from] time::error::Format),
+
+    /// Error parsing time values
+    #[cfg(feature = "chrono")]
+    #[error("chrono parse error: {0}")]
+    ChronoParse(#[from] chrono::ParseError),
 }
 
 /// A specialized Result type for rusty_paseto operations.

src/generic/claims/mod.rs

@@ -32,15 +32,26 @@ mod unit_tests {
   //TODO: need more comprehensive tests than these to flesh out the additionl error types
   use super::*;
   use anyhow::Result;
-  //use chrono::prelude::*;
   use std::convert::TryFrom;
+
+  #[cfg(feature = "time")]
   use time::format_description::well_known::Rfc3339;
 
+  #[cfg(feature = "time")]
+  fn now_rfc3339() -> String {
+    time::OffsetDateTime::now_utc().format(&Rfc3339).expect("format failed")
+  }
+
+  #[cfg(feature = "chrono")]
+  fn now_rfc3339() -> String {
+    chrono::Utc::now().to_rfc3339()
+  }
+
   #[test]
   fn test_expiration_claim() -> Result<()> {
     // setup
     // a good time format
-    let now = time::OffsetDateTime::now_utc().format(&Rfc3339)?;
+    let now = now_rfc3339();
 
     assert!(ExpirationClaim::try_from("hello").is_err());
     let claim = ExpirationClaim::try_from(now);
@@ -56,7 +67,7 @@ mod unit_tests {
   fn test_not_before_claim() -> Result<()> {
     // setup
     // a good time format
-    let now = time::OffsetDateTime::now_utc().format(&Rfc3339)?;
+    let now = now_rfc3339();
 
     assert!(NotBeforeClaim::try_from("hello").is_err());
     let claim = NotBeforeClaim::try_from(now);
@@ -72,7 +83,7 @@ mod unit_tests {
   fn test_issued_at_claim() -> Result<()> {
     // setup
     // a good time format
-    let now = time::OffsetDateTime::now_utc().format(&Rfc3339)?;
+    let now = now_rfc3339();
 
     assert!(IssuedAtClaim::try_from("hello").is_err());
     let claim = IssuedAtClaim::try_from(now);

src/lib.rs

@@ -36,7 +36,7 @@
 //!
 //!
 //! # Usage
-//! `rusty_paseto` is meant to be flexible and configurable for your specific use case.  Whether you want to get started quickly with sensible defaults, create your own version of `rusty_paseto` in order to customize your own defaults and functionality or just want to use the core PASETO crypto features, the crate is heavily feature gated to allow for your needs.  
+//! `rusty_paseto` is meant to be flexible and configurable for your specific use case.  Whether you want to get started quickly with sensible defaults, create your own version of `rusty_paseto` in order to customize your own defaults and functionality or just want to use the core PASETO crypto features, the crate is heavily feature gated to allow for your needs.
 
 //! ## Architecture
 
@@ -164,7 +164,7 @@
 //! ```
 //! ### core
 //!
-//! The core architectural layer is the most basic PASETO implementation as it accepts a Payload, optional Footer and (if v3 or v4) an optional Implicit Assertion along with the appropriate key to encrypt/sign and decrypt/verify basic strings.  
+//! The core architectural layer is the most basic PASETO implementation as it accepts a Payload, optional Footer and (if v3 or v4) an optional Implicit Assertion along with the appropriate key to encrypt/sign and decrypt/verify basic strings.
 //!
 //! <img src="https://github.com/rrrodzilla/rusty_paseto/raw/main/assets/RustyPasetoCoreArchitecture.png" width="150" />
 //!
@@ -386,9 +386,13 @@
 //! // must include
 //! use std::convert::TryFrom;
 //! let key = PasetoSymmetricKey::<V4, Local>::from(Key::from(b"wubbalubbadubdubwubbalubbadubdub"));
-//! // real-world example using the time crate to expire 5 minutes from now
+//! // real-world example: expire 5 minutes from now
+//! # #[cfg(feature = "time")]
 //! # use time::format_description::well_known::Rfc3339;
+//! # #[cfg(feature = "time")]
 //! # let in_5_minutes = (time::OffsetDateTime::now_utc() + time::Duration::minutes(5)).format(&Rfc3339)?;
+//! # #[cfg(feature = "chrono")]
+//! # let in_5_minutes = (chrono::Utc::now() + chrono::Duration::minutes(5)).to_rfc3339();
 //!
 //! let token = PasetoBuilder::<V4, Local>::default()
 //!   // note the TryFrom implmentation for ExpirationClaim
@@ -406,18 +410,22 @@
 //!
 //! A **1 hour** `ExpirationClaim` is set by default because the use case for non-expiring tokens in the world of security tokens is fairly limited.
 //! Omitting an expiration claim or forgetting to require one when processing them
-//! is almost certainly an oversight rather than a deliberate choice.  
+//! is almost certainly an oversight rather than a deliberate choice.
 //!
 //! When it is a deliberate choice, you have the opportunity to deliberately remove this claim from the Builder.
 //! The method call required to do so ensures readers of the code understand the implicit risk.
 //! ```rust
 //! # #[cfg(feature = "default")]
 //! # {
 //! # use rusty_paseto::prelude::*;
-//! # use time::format_description::well_known::Rfc3339;
 //! # use std::convert::TryFrom;
-//! # let in_5_minutes = (time::OffsetDateTime::now_utc() + time::Duration::minutes(5)).format(&Rfc3339)?;
 //! # let key = PasetoSymmetricKey::<V4, Local>::from(Key::from(b"wubbalubbadubdubwubbalubbadubdub"));
+//! # #[cfg(feature = "time")]
+//! # use time::format_description::well_known::Rfc3339;
+//! # #[cfg(feature = "time")]
+//! # let in_5_minutes = (time::OffsetDateTime::now_utc() + time::Duration::minutes(5)).format(&Rfc3339)?;
+//! # #[cfg(feature = "chrono")]
+//! # let in_5_minutes = (chrono::Utc::now() + chrono::Duration::minutes(5)).to_rfc3339();
 //! let token = PasetoBuilder::<V4, Local>::default()
 //!   .set_claim(ExpirationClaim::try_from(in_5_minutes)?)
 //!   // even if you set an expiration claim (as above) it will be ignored
@@ -435,15 +443,20 @@
 //! # #[cfg(all(test,feature = "v4_local"))]
 //! # {
 //! # use rusty_paseto::prelude::*;
-//! # use time::format_description::well_known::Rfc3339;
 //! # // must include
 //! # use std::convert::TryFrom;
 //! # let key = PasetoSymmetricKey::<V4, Local>::from(Key::from(b"wubbalubbadubdubwubbalubbadubdub"));
-//! # // real-world example using the time crate to expire 5 minutes from now
+//! # #[cfg(feature = "time")]
+//! # use time::format_description::well_known::Rfc3339;
+//! # #[cfg(feature = "time")]
 //! # let in_5_minutes = (time::OffsetDateTime::now_utc() + time::Duration::minutes(5)).format(&Rfc3339)?;
-//! // real-world example using the time crate to prevent the token from being used before 2
-//! // minutes from now
+//! # #[cfg(feature = "chrono")]
+//! # let in_5_minutes = (chrono::Utc::now() + chrono::Duration::minutes(5)).to_rfc3339();
+//! // set not-before to 2 minutes in the future
+//! # #[cfg(feature = "time")]
 //! let in_2_minutes = (time::OffsetDateTime::now_utc() + time::Duration::minutes(2)).format(&Rfc3339)?;
+//! # #[cfg(feature = "chrono")]
+//! # let in_2_minutes = (chrono::Utc::now() + chrono::Duration::minutes(2)).to_rfc3339();
 //!
 //! let token = PasetoBuilder::<V4, Local>::default()
 //!   //json payload key: "exp"
@@ -671,6 +684,13 @@ compile_error!(
      See: https://github.com/rrrodzilla/rusty_paseto/issues/48"
 );
 
+// Ensure exactly one time backend is selected when the prelude is used.
+#[cfg(all(feature = "time", feature = "chrono"))]
+compile_error!("features `time` and `chrono` are mutually exclusive. Enable exactly one time backend");
+
+#[cfg(all(not(feature = "time"), not(feature = "chrono")))]
+compile_error!("a time backend is required. Enable either the `time` feature or `chrono`");
+
 //public interface
 #[cfg(feature = "core")]
 pub mod core;

src/prelude/error.rs

@@ -21,5 +21,10 @@ pub enum GeneralPasetoError {
   },
   /// An error with the data format
   #[error(transparent)]
+  #[cfg(feature = "time")]
   RFC3339Date(#[from] time::error::Format),
+  /// An error parsing a date/time value with chrono
+  #[error(transparent)]
+  #[cfg(feature = "chrono")]
+  ChronoParse(#[from] chrono::ParseError),
 }