1 files changed, 84 insertions, 0 deletions
diff --git a/examples/tags.rs b/examples/tags.rs
new file mode 100644
index 0000000..9281b9b
--- /dev/null
+++ b/examples/tags.rs
@@ -0,0 +1,84 @@
+use serde::de::{Deserialize, Deserializer};
+use serde::ser::{Serialize, Serializer};
+use serde_cbor::tags::Tagged;
+use serde_cbor::Value;
+use serde_derive::{Deserialize, Serialize};
+use std::error::Error;
+
+/// https://tools.ietf.org/html/rfc7049#section-2.4.1
+#[derive(Debug, PartialEq)]
+struct Date(String);
+
+impl Serialize for Date {
+    fn serialize<S: Serializer>(&self, s: S) -> Result<S::Ok, S::Error> {
+        Tagged::new(Some(0), &self.0).serialize(s)
+    }
+}
+
+impl<'de> Deserialize<'de> for Date {
+    fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error> {
+        let tagged = Tagged::<String>::deserialize(deserializer)?;
+        match tagged.tag {
+            Some(0) | None => Ok(Date(tagged.value)),
+            Some(_) => Err(serde::de::Error::custom("unexpected tag")),
+        }
+    }
+}
+
+/// https://tools.ietf.org/html/rfc7049#section-2.4.4.3
+#[derive(Debug, PartialEq)]
+struct Uri(String);
+
+impl Serialize for Uri {
+    fn serialize<S: Serializer>(&self, s: S) -> Result<S::Ok, S::Error> {
+        Tagged::new(Some(32), &self.0).serialize(s)
+    }
+}
+impl<'de> Deserialize<'de> for Uri {
+    fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error> {
+        let tagged = Tagged::<String>::deserialize(deserializer)?;
+        match tagged.tag {
+            // allow deserialization even if there is no tag. Allows roundtrip via other formats such as json
+            Some(0) | None => Ok(Uri(tagged.value)),
+            Some(_) => Err(serde::de::Error::custom("unexpected tag")),
+        }
+    }
+}
+
+#[derive(Debug, Serialize, Deserialize, PartialEq)]
+struct Bookmark {
+    title: String,
+    link: Uri,
+    created: Date,
+}
+
+fn main() -> Result<(), Box<dyn Error>> {
+    let bookmark = Bookmark {
+        title: "The Example Domain".into(),
+        link: Uri("http://example.org/".into()),
+        created: Date("2003-12-13T18:30:02Z".into()),
+    };
+
+    // serialize the struct to bytes
+    let bytes1 = serde_cbor::to_vec(&bookmark)?;
+    // deserialize to a serde_cbor::Value
+    let value1: Value = serde_cbor::from_slice(&bytes1)?;
+    println!("{:?}", value1);
+    // serialize the value to bytes
+    let bytes2 = serde_cbor::to_vec(&value1)?;
+    // deserialize to a serde_cbor::Value
+    let value2: Value = serde_cbor::from_slice(&bytes2)?;
+    println!("{:?}", value2);
+    // deserialize to a Bookmark
+    let result: Bookmark = serde_cbor::from_slice(&bytes2)?;
+
+    // check that the roundtrip was successful
+    assert_eq!(value1, value2);
+    assert_eq!(bookmark, result);
+
+    // check that going via a format that does not support tags does work
+    // let json = serde_json::to_vec(&bookmark)?;
+    // let result: Bookmark = serde_json::from_slice(&json)?;
+    // assert_eq!(bookmark, result);
+    Ok(())
+}