Define the global KeySpace interface

Signed-off-by: Lee Smet <lee.smet@hotmail.com>

vault/src/error.rs

@@ -1,3 +1,20 @@
+#[derive(Debug)]
+/// Errors encountered while using the vault
+pub enum Error {
+    /// An error during cryptographic operations
+    Crypto(CryptoError),
+}
+
+impl core::fmt::Display for Error {
+    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
+        match self {
+            Error::Crypto(e) => f.write_fmt(format_args!("crypto: {e}")),
+        }
+    }
+}
+
+impl core::error::Error for Error {}
+
 #[derive(Debug)]
 /// Errors generated by the vault or keys.
 ///
@@ -18,7 +35,7 @@ pub enum CryptoError {
 }
 
 impl core::fmt::Display for CryptoError {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
         match self {
             CryptoError::InvalidKeySize => f.write_str("provided key is not the correct size"),
             CryptoError::EncryptionFailed => f.write_str("encryption failure"),
@@ -33,3 +50,9 @@ impl core::fmt::Display for CryptoError {
 }
 
 impl core::error::Error for CryptoError {}
+
+impl From<CryptoError> for Error {
+    fn from(value: CryptoError) -> Self {
+        Self::Crypto(value)
+    }
+}

vault/src/keyspace.rs

@@ -0,0 +1,50 @@
+#[cfg(target_arch = "wasm32")]
+mod wasm;
+
+#[cfg(not(target_arch = "wasm32"))]
+mod fallback;
+
+#[cfg(target_arch = "wasm32")]
+use wasm::KeySpace as KS;
+
+#[cfg(not(target_arch = "wasm32"))]
+use fallback::KeySpace as KS;
+
+use crate::{error::Error, key::Key};
+
+/// A keyspace represents a group of stored cryptographic keys. The storage is encrypted, a
+/// password must be provided when opening the KeySpace to decrypt the keys.
+pub struct KeySpace {
+    store: KS,
+}
+
+/// Wasm32 constructor
+#[cfg(target_arch = "wasm32")]
+impl KeySpace {}
+
+/// Non-wasm constructor
+#[cfg(not(target_arch = "wasm32"))]
+impl KeySpace {}
+
+/// Exposed methods, platform independant
+impl KeySpace {
+    /// Get a [`Key`] previously stored under the provided name.
+    async fn get(&self, key: &str) -> Result<Option<Key>, Error> {
+        todo!();
+    }
+
+    /// Store a [`Key`] under the provided name.
+    async fn set(&self, key: &str, value: Key) -> Result<(), Error> {
+        todo!();
+    }
+
+    /// Delete the [`Key`] stored under the provided name.
+    async fn delete(&self, key: &str) -> Result<(), Error> {
+        todo!();
+    }
+
+    /// Iterate over all stored [`keys`](Key) in the KeySpace
+    async fn iter(&self) -> Result<impl Iterator<Item = (String, Key)>, Error> {
+        todo!()
+    }
+}

vault/src/keyspace/fallback.rs

@@ -0,0 +1,2 @@
+/// A KeySpace using the filesystem as storage
+pub mod KeySpace {}

vault/src/keyspace/wasm.rs

@@ -0,0 +1,2 @@
+/// KeySpace represents an IndexDB keyspace
+pub struct KeySpace {}

vault/src/lib.rs

@@ -1,3 +1,4 @@
 pub mod error;
 pub mod key;
+pub mod keyspace;
 pub mod kvs;