From 9b457564bbba67fb1978e1436b405d1db04b8012 Mon Sep 17 00:00:00 2001
From: trivernis <trivernis@protonmail.com>
Date: Tue, 2 Nov 2021 19:38:48 +0100
Subject: [PATCH] Add API version validation

Signed-off-by: trivernis <trivernis@protonmail.com>
---
 mediarepo-api/src/client_api/error.rs   |  7 +++-
 mediarepo-api/src/client_api/mod.rs     | 13 +++++--
 mediarepo-api/src/tauri_plugin/error.rs |  1 +
 mediarepo-api/src/types/misc.rs         | 52 ++++++++++++++++++++++++-
 4 files changed, 66 insertions(+), 7 deletions(-)

diff --git a/mediarepo-api/src/client_api/error.rs b/mediarepo-api/src/client_api/error.rs
index bd8f8df..0e88754 100644
--- a/mediarepo-api/src/client_api/error.rs
+++ b/mediarepo-api/src/client_api/error.rs
@@ -5,5 +5,8 @@ pub type ApiResult<T> = Result<T, ApiError>;
 #[derive(Debug, Error)]
 pub enum ApiError {
     #[error(transparent)]
-    IPC(#[from] rmp_ipc::error::Error)
-}
\ No newline at end of file
+    IPC(#[from] rmp_ipc::error::Error),
+
+    #[error("The servers api version is incompatible with the api client")]
+    VersionMismatch,
+}
diff --git a/mediarepo-api/src/client_api/mod.rs b/mediarepo-api/src/client_api/mod.rs
index 3f27ac5..fb60401 100644
--- a/mediarepo-api/src/client_api/mod.rs
+++ b/mediarepo-api/src/client_api/mod.rs
@@ -2,10 +2,10 @@ pub mod error;
 pub mod file;
 pub mod tag;
 
-use crate::client_api::error::ApiResult;
+use crate::client_api::error::{ApiError, ApiResult};
 use crate::client_api::file::FileApi;
 use crate::client_api::tag::TagApi;
-use crate::types::misc::InfoResponse;
+use crate::types::misc::{check_apis_compatible, get_api_version, InfoResponse};
 use async_trait::async_trait;
 use rmp_ipc::context::{PoolGuard, PooledContext};
 use rmp_ipc::ipc::context::Context;
@@ -72,8 +72,15 @@ impl ApiClient {
             .address(address)
             .build_pooled_client(8)
             .await?;
+        let client = Self::new(ctx);
+        let info = client.info().await?;
+        let server_api_version = info.api_version();
 
-        Ok(Self::new(ctx))
+        if !check_apis_compatible(get_api_version(), server_api_version) {
+            Err(ApiError::VersionMismatch)
+        } else {
+            Ok(client)
+        }
     }
 
     /// Returns information about the connected ipc server
diff --git a/mediarepo-api/src/tauri_plugin/error.rs b/mediarepo-api/src/tauri_plugin/error.rs
index 5abf4e3..1480239 100644
--- a/mediarepo-api/src/tauri_plugin/error.rs
+++ b/mediarepo-api/src/tauri_plugin/error.rs
@@ -40,6 +40,7 @@ impl From<ApiError> for PluginError {
                     format!("{:?}", e)
                 }
             },
+            ApiError::VersionMismatch => {String::from("The servers API version is not supported by the client. Please make sure both are up to date.")}
         };
         Self { message }
     }
diff --git a/mediarepo-api/src/types/misc.rs b/mediarepo-api/src/types/misc.rs
index 137524f..73ca70d 100644
--- a/mediarepo-api/src/types/misc.rs
+++ b/mediarepo-api/src/types/misc.rs
@@ -1,7 +1,55 @@
-use serde::{Serialize, Deserialize};
+use serde::{Deserialize, Serialize};
 
 #[derive(Clone, Debug, Serialize, Deserialize)]
 pub struct InfoResponse {
     pub name: String,
     pub version: String,
-}
\ No newline at end of file
+    pub(crate) api_version: (u32, u32, u32),
+}
+
+impl InfoResponse {
+    /// Creates a new info response
+    pub fn new(name: String, version: String) -> Self {
+        Self {
+            name,
+            version,
+            api_version: get_api_version(),
+        }
+    }
+
+    /// Returns the api version of the crate
+    pub fn api_version(&self) -> (u32, u32, u32) {
+        self.api_version
+    }
+}
+
+/// Retrieves the api version of the crate version in numbers
+pub fn get_api_version() -> (u32, u32, u32) {
+    let mut major = env!("CARGO_PKG_VERSION_MAJOR").to_string();
+    let mut minor = env!("CARGO_PKG_VERSION_MINOR").to_string();
+    let mut patch = env!("CARGO_PKG_VERSION_PATCH").to_string();
+    major.retain(char::is_numeric);
+    minor.retain(char::is_numeric);
+    patch.retain(char::is_numeric);
+    let major = major
+        .parse::<u32>()
+        .expect("Failed to parse major crate version");
+    let minor = minor
+        .parse::<u32>()
+        .expect("Failed to parse minor crate version");
+    let patch = patch
+        .parse::<u32>()
+        .expect("Failed to parse patch crate version");
+
+    (major, minor, patch)
+}
+
+/// Checks if the api the client consumes is compatible to the one the server provides
+pub fn check_apis_compatible(
+    client_version: (u32, u32, u32),
+    server_version: (u32, u32, u32),
+) -> bool {
+    // the major version must be the same while the client minor version can be lower than the servers
+    // so that the client has access to all its supported functionality
+    client_version.0 == server_version.0 && client_version.1 <= server_version.1
+}