Add custom Duration and Timestamp types for conversion with serde (#89)

* Add custom Duration and Timestamp types for conversion with serde

* Update serde example with Duration and Timestamps

* Improve duration and timestamp serde example, fix copied test var name.

* Move Duration and Timestamp examples to respective types docs

* Refactor Duration and Timestamp to be compatible with other parsers

* Manually serialize Timestamps

* Use chrono::DateTime serialization impl

* Put Duration and Timestamp types behind chrono feature

* Fix lint for SerializeTimestamp

* Combine json time-type tests

* Add SAFTEY comments to asserts for TimeSerializer

* Replace TimeSerializer asserts with errors

interpreter/Cargo.toml

@@ -13,7 +13,7 @@ cel-parser = { path = "../parser", version = "0.8.0" }
 
 nom = "7.1.3"
 
-chrono = { version = "0.4", default-features = false, features = ["alloc"], optional = true }
+chrono = { version = "0.4", default-features = false, features = ["alloc", "serde"], optional = true }
 regex = { version = "1.10.5", optional = true }
 serde = "1.0"
 serde_json = { version = "1.0", optional = true }

interpreter/src/lib.rs

@@ -20,6 +20,8 @@ mod resolvers;
 
 #[cfg(feature = "chrono")]
 mod duration;
+#[cfg(feature = "chrono")]
+pub use ser::{Duration, Timestamp};
 
 mod ser;
 pub use ser::to_value;