write the v5 dump import

dump/src/reader/v5/meta.rs

@@ -1,14 +1,137 @@
-use serde::{Deserialize, Serialize};
+use std::{
+    fmt::{self, Display, Formatter},
+    marker::PhantomData,
+    str::FromStr,
+};
+
+use serde::{de::Visitor, Deserialize, Deserializer};
 use uuid::Uuid;
 
-#[derive(Serialize, Deserialize, Debug)]
+use super::settings::{Settings, Unchecked};
+
+#[derive(Deserialize, Debug)]
 pub struct IndexUuid {
     pub uid: String,
     pub index_meta: IndexMeta,
 }
 
-#[derive(Serialize, Deserialize, Debug)]
+#[derive(Deserialize, Debug)]
 pub struct IndexMeta {
     pub uuid: Uuid,
     pub creation_task_id: usize,
 }
+
+// There is one in each indexes under `meta.json`.
+#[derive(Deserialize)]
+pub struct DumpMeta {
+    pub settings: Settings<Unchecked>,
+    pub primary_key: Option<String>,
+}
+
+#[derive(Deserialize, Debug, Clone, PartialEq, Eq)]
+pub struct IndexUid(pub String);
+
+impl TryFrom<String> for IndexUid {
+    type Error = IndexUidFormatError;
+
+    fn try_from(uid: String) -> Result<Self, Self::Error> {
+        if !uid
+            .chars()
+            .all(|x| x.is_ascii_alphanumeric() || x == '-' || x == '_')
+            || uid.is_empty()
+            || uid.len() > 400
+        {
+            Err(IndexUidFormatError { invalid_uid: uid })
+        } else {
+            Ok(IndexUid(uid))
+        }
+    }
+}
+
+impl FromStr for IndexUid {
+    type Err = IndexUidFormatError;
+
+    fn from_str(uid: &str) -> Result<IndexUid, IndexUidFormatError> {
+        uid.to_string().try_into()
+    }
+}
+
+impl From<IndexUid> for String {
+    fn from(uid: IndexUid) -> Self {
+        uid.into_inner()
+    }
+}
+
+#[derive(Debug)]
+pub struct IndexUidFormatError {
+    pub invalid_uid: String,
+}
+
+impl Display for IndexUidFormatError {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        write!(
+            f,
+            "invalid index uid `{}`, the uid must be an integer \
+            or a string containing only alphanumeric characters \
+            a-z A-Z 0-9, hyphens - and underscores _.",
+            self.invalid_uid,
+        )
+    }
+}
+
+impl std::error::Error for IndexUidFormatError {}
+
+/// A type that tries to match either a star (*) or
+/// any other thing that implements `FromStr`.
+#[derive(Debug)]
+pub enum StarOr<T> {
+    Star,
+    Other(T),
+}
+
+impl<'de, T, E> Deserialize<'de> for StarOr<T>
+where
+    T: FromStr<Err = E>,
+    E: Display,
+{
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        /// Serde can't differentiate between `StarOr::Star` and `StarOr::Other` without a tag.
+        /// Simply using `#[serde(untagged)]` + `#[serde(rename="*")]` will lead to attempting to
+        /// deserialize everything as a `StarOr::Other`, including "*".
+        /// [`#[serde(other)]`](https://serde.rs/variant-attrs.html#other) might have helped but is
+        /// not supported on untagged enums.
+        struct StarOrVisitor<T>(PhantomData<T>);
+
+        impl<'de, T, FE> Visitor<'de> for StarOrVisitor<T>
+        where
+            T: FromStr<Err = FE>,
+            FE: Display,
+        {
+            type Value = StarOr<T>;
+
+            fn expecting(&self, formatter: &mut Formatter) -> std::fmt::Result {
+                formatter.write_str("a string")
+            }
+
+            fn visit_str<SE>(self, v: &str) -> Result<Self::Value, SE>
+            where
+                SE: serde::de::Error,
+            {
+                match v {
+                    "*" => Ok(StarOr::Star),
+                    v => {
+                        let other = FromStr::from_str(v).map_err(|e: T::Err| {
+                            SE::custom(format!("Invalid `other` value: {}", e))
+                        })?;
+                        Ok(StarOr::Other(other))
+                    }
+                }
+            }
+        }
+
+        deserializer.deserialize_str(StarOrVisitor(PhantomData))
+    }
+}