Feat(core): Add manual implementation of Diff on DID. (#62)

* add manual did_diff.

* remove default from context.

* fix clippy.

* fix clippy.

identity_core/src/did/did.rs

@@ -1,5 +1,4 @@
 use core::str::FromStr;
-use identity_diff::Diff;
 use serde::{
     de::{self, Deserialize, Deserializer, Visitor},
     ser::{Serialize, Serializer},
@@ -18,8 +17,7 @@ const LEADING_TOKENS: &str = "did";
 type DIDTuple = (String, Option<String>);
 
 /// a Decentralized identity structure.
-#[derive(Debug, PartialEq, Default, Eq, Clone, Diff, Hash, Ord, PartialOrd)]
-#[diff(from_into)]
+#[derive(Debug, PartialEq, Default, Eq, Clone, Hash, Ord, PartialOrd)]
 pub struct DID {
     pub method_name: String,
     pub id_segments: Vec<String>,
@@ -216,8 +214,7 @@ impl Serialize for DID {
 }
 
 /// a DID Params struct.
-#[derive(Debug, PartialEq, Eq, Clone, Default, Hash, PartialOrd, Ord, Diff, DDeserialize, DSerialize)]
-#[diff(from_into)]
+#[derive(Debug, PartialEq, Eq, Clone, Default, Hash, PartialOrd, Ord, DDeserialize, DSerialize)]
 pub struct Param {
     pub key: String,
     pub value: Option<String>,

identity_core/src/did/did_diff.rs

@@ -0,0 +1,237 @@
+use crate::did::{Param, DID};
+use identity_diff::Diff;
+
+use serde::{Deserialize as DDeserialize, Serialize as DSerialize};
+
+#[derive(Debug, PartialEq, Default, Clone, DDeserialize, DSerialize)]
+#[serde(from = "DID", into = "DID")]
+pub struct DiffDID {
+    #[serde(skip_serializing_if = "String::is_empty")]
+    pub method_name: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub id_segments: Option<<Vec<String> as identity_diff::Diff>::Type>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub path_segments: Option<<Option<Vec<String>> as identity_diff::Diff>::Type>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub query: Option<<Option<Vec<Param>> as identity_diff::Diff>::Type>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub fragment: Option<<Option<String> as identity_diff::Diff>::Type>,
+}
+
+#[derive(Debug, PartialEq, Default, Clone, DSerialize, DDeserialize)]
+#[serde(from = "Param", into = "Param")]
+pub struct DiffParam {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub key: Option<<String as identity_diff::Diff>::Type>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub value: Option<<Option<String> as identity_diff::Diff>::Type>,
+}
+
+impl Diff for DID {
+    type Type = DiffDID;
+
+    fn diff(&self, other: &Self) -> identity_diff::Result<Self::Type> {
+        let method_name = if self.method_name == other.method_name {
+            self.method_name.clone()
+        } else {
+            other.method_name.clone()
+        };
+
+        Ok(DiffDID {
+            method_name,
+            id_segments: if self.id_segments == other.id_segments {
+                None
+            } else {
+                Some(self.id_segments.diff(&other.id_segments)?)
+            },
+            path_segments: if self.path_segments == other.path_segments || other.path_segments == None {
+                None
+            } else {
+                Some(self.path_segments.diff(&other.path_segments)?)
+            },
+            query: if self.query == other.query || other.query == None {
+                None
+            } else {
+                Some(self.query.diff(&other.query)?)
+            },
+            fragment: if self.fragment == other.fragment || other.fragment == None {
+                None
+            } else {
+                Some(self.fragment.diff(&other.fragment)?)
+            },
+        })
+    }
+
+    fn merge(&self, diff: Self::Type) -> identity_diff::Result<Self> {
+        Ok(Self {
+            method_name: if self.method_name == diff.method_name {
+                self.method_name.clone()
+            } else {
+                diff.method_name
+            },
+            id_segments: if let Some(d) = diff.id_segments {
+                self.id_segments.merge(d)?
+            } else {
+                self.id_segments.clone()
+            },
+            path_segments: if let Some(d) = diff.path_segments {
+                self.path_segments.merge(d)?
+            } else {
+                self.path_segments.clone()
+            },
+            query: if let Some(d) = diff.query {
+                self.query.merge(d)?
+            } else {
+                self.query.clone()
+            },
+            fragment: if let Some(d) = diff.fragment {
+                self.fragment.merge(d)?
+            } else {
+                self.fragment.clone()
+            },
+        })
+    }
+
+    fn into_diff(self) -> identity_diff::Result<Self::Type> {
+        let Self {
+            method_name,
+            id_segments,
+            path_segments,
+            query,
+            fragment,
+        } = self;
+
+        Ok(DiffDID {
+            method_name,
+            id_segments: Some(id_segments.into_diff()?),
+            path_segments: if let identity_diff::option::DiffOption::Some(_) = path_segments.clone().into_diff()? {
+                Some(path_segments.into_diff()?)
+            } else {
+                None
+            },
+            query: if let identity_diff::option::DiffOption::Some(_) = query.clone().into_diff()? {
+                Some(query.into_diff()?)
+            } else {
+                None
+            },
+            fragment: if let identity_diff::option::DiffOption::Some(_) = fragment.clone().into_diff()? {
+                Some(fragment.into_diff()?)
+            } else {
+                None
+            },
+        })
+    }
+
+    fn from_diff(diff: Self::Type) -> identity_diff::Result<Self> {
+        let DiffDID {
+            method_name,
+            id_segments,
+            path_segments,
+            query,
+            fragment,
+        } = diff;
+
+        Ok(Self {
+            method_name,
+            id_segments: <Vec<String>>::from_diff(match id_segments {
+                Some(v) => v,
+                None => <Vec<String>>::default().into_diff()?,
+            })?,
+            path_segments: <Option<Vec<String>>>::from_diff(match path_segments {
+                Some(v) => v,
+                None => <Option<Vec<String>>>::default().into_diff()?,
+            })?,
+            query: <Option<Vec<Param>>>::from_diff(match query {
+                Some(v) => v,
+                None => <Option<Vec<Param>>>::default().into_diff()?,
+            })?,
+            fragment: <Option<String>>::from_diff(match fragment {
+                Some(v) => v,
+                None => <Option<String>>::default().into_diff()?,
+            })?,
+        })
+    }
+}
+
+impl Diff for Param {
+    type Type = DiffParam;
+
+    fn diff(&self, other: &Self) -> identity_diff::Result<Self::Type> {
+        Ok(DiffParam {
+            key: if self.key == other.key {
+                None
+            } else {
+                Some(self.key.diff(&other.key)?)
+            },
+            value: if self.value == other.value || other.value == None {
+                None
+            } else {
+                Some(self.value.diff(&other.value)?)
+            },
+        })
+    }
+
+    fn merge(&self, diff: Self::Type) -> identity_diff::Result<Self> {
+        Ok(Self {
+            key: if let Some(d) = diff.key {
+                self.key.merge(d)?
+            } else {
+                self.key.clone()
+            },
+            value: if let Some(d) = diff.value {
+                self.value.merge(d)?
+            } else {
+                self.value.clone()
+            },
+        })
+    }
+
+    fn into_diff(self) -> identity_diff::Result<Self::Type> {
+        let Self { key, value } = self;
+
+        Ok(DiffParam {
+            key: Some(key.into_diff()?),
+            value: if let identity_diff::option::DiffOption::Some(_) = value.clone().into_diff()? {
+                Some(value.into_diff()?)
+            } else {
+                None
+            },
+        })
+    }
+    fn from_diff(diff: Self::Type) -> identity_diff::Result<Self> {
+        let DiffParam { key, value } = diff;
+
+        Ok(Self {
+            key: <String>::from_diff(match key {
+                Some(v) => v,
+                None => <String>::default().into_diff()?,
+            })?,
+            value: <Option<String>>::from_diff(match value {
+                Some(v) => v,
+                None => <Option<String>>::default().into_diff()?,
+            })?,
+        })
+    }
+}
+
+impl From<DID> for DiffDID {
+    fn from(did: DID) -> Self {
+        did.into_diff().expect("Unable to convert to diff")
+    }
+}
+impl From<DiffDID> for DID {
+    fn from(diff: DiffDID) -> Self {
+        Self::from_diff(diff).expect("Unable to convert from diff")
+    }
+}
+
+impl From<Param> for DiffParam {
+    fn from(param: Param) -> Self {
+        param.into_diff().expect("Unable to convert to diff")
+    }
+}
+impl From<DiffParam> for Param {
+    fn from(diff: DiffParam) -> Self {
+        Self::from_diff(diff).expect("Unable to convert from diff")
+    }
+}

identity_core/src/did/mod.rs

@@ -1,6 +1,7 @@
 mod authentication;
 #[allow(clippy::module_inception)]
 mod did;
+mod did_diff;
 mod document;
 mod parser;
 mod service;