fix serializer failure on unknown MediaType string

src/entities/attachment.rs

@@ -47,7 +47,9 @@ pub struct ImageDetails {
 }
 
 /// The type of media attachment.
-#[derive(Debug, Deserialize, Clone, Copy, PartialEq)]
+#[derive(Debug, Deserialize, Clone, PartialEq)]
+// Deserialize "Other" trick from https://github.com/serde-rs/serde/issues/912#issuecomment-803097289
+#[serde(remote = "MediaType")]
 pub enum MediaType {
     /// An image.
     #[serde(rename = "image")]
@@ -55,10 +57,52 @@ pub enum MediaType {
     /// A video file.
     #[serde(rename = "video")]
     Video,
+    /// An audio file.
+    #[serde(rename = "audio")]
+    Audio,
     /// A gifv format file.
     #[serde(rename = "gifv")]
     Gifv,
     /// Unknown format.
     #[serde(rename = "unknown")]
     Unknown,
+    /// Anything else
+    #[serde(skip_deserializing)]
+    Other(String),
+}
+
+use std::str::FromStr;
+use serde::de::{value, Deserializer, IntoDeserializer};
+
+impl FromStr for MediaType {
+    type Err = value::Error;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        Self::deserialize(s.into_deserializer())
+    }
+}
+
+impl<'de> Deserialize<'de> for MediaType {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+        where D: Deserializer<'de>
+    {
+        let s = String::deserialize(deserializer)?;
+        let deserialized = Self::from_str(&s).unwrap_or_else(|_| {
+            Self::Other(s)
+        });
+        Ok(deserialized)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::entities::prelude::MediaType;
+    use serde_json::Value;
+
+    #[test]
+    fn test_deserialize_media_type() {
+        assert_eq!(MediaType::Image, serde_json::from_value(Value::String("image".to_owned())).unwrap());
+        assert_eq!(MediaType::Audio, serde_json::from_value(Value::String("audio".to_owned())).unwrap());
+        assert_eq!(MediaType::Other("pleroma_weird_thing".to_string()), serde_json::from_value(Value::String("pleroma_weird_thing".to_owned())).unwrap());
+    }
 }