Restrict working only with compliant janus API version (#219)

migrations/2021-02-01-193110_add_api_version_to_janus_backend/down.sql

@@ -0,0 +1 @@
+ALTER TABLE janus_backend DROP COLUMN api_version;

migrations/2021-02-01-193110_add_api_version_to_janus_backend/up.sql

@@ -0,0 +1 @@
+ALTER TABLE janus_backend ADD COLUMN api_version TEXT NOT NULL DEFAULT 'v1';

src/app/mod.rs

@@ -21,7 +21,7 @@ use svc_authz::cache::{Cache as AuthzCache, ConnectionPool as RedisConnectionPoo
 use crate::app::context::GlobalContext;
 use crate::app::error::{Error as AppError, ErrorKind as AppErrorKind};
 use crate::app::metrics::{DynamicStatsCollector, StatsRoute};
-use crate::backend::janus::Client as JanusClient;
+use crate::backend::janus::{Client as JanusClient, JANUS_API_VERSION};
 use crate::config::{self, Config, KruonisConfig};
 use crate::db::ConnectionPool;
 use context::{AppContext, JanusTopics};
@@ -181,7 +181,8 @@ fn subscribe(agent: &mut Agent, agent_id: &AgentId, config: &Config) -> Result<J
         .context("Error subscribing to multicast requests")?;
 
     // Janus status events
-    let subscription = Subscription::broadcast_events(&config.backend.id, API_VERSION, "status");
+    let subscription =
+        Subscription::broadcast_events(&config.backend.id, JANUS_API_VERSION, "status");
 
     agent
         .subscribe(&subscription, QoS::AtLeastOnce, Some(&group))
@@ -192,7 +193,8 @@ fn subscribe(agent: &mut Agent, agent_id: &AgentId, config: &Config) -> Result<J
         .context("Error building janus events subscription topic")?;
 
     // Janus events
-    let subscription = Subscription::broadcast_events(&config.backend.id, API_VERSION, "events");
+    let subscription =
+        Subscription::broadcast_events(&config.backend.id, JANUS_API_VERSION, "events");
 
     agent
         .subscribe(&subscription, QoS::AtLeastOnce, Some(&group))

src/db/janus_backend.rs

@@ -4,6 +4,7 @@ use diesel::result::Error;
 use svc_agent::AgentId;
 use uuid::Uuid;
 
+use crate::backend::janus::JANUS_API_VERSION;
 use crate::schema::janus_backend;
 
 pub(crate) type AllColumns = (
@@ -13,6 +14,7 @@ pub(crate) type AllColumns = (
     janus_backend::created_at,
     janus_backend::capacity,
     janus_backend::balancer_capacity,
+    janus_backend::api_version,
 );
 
 pub(crate) const ALL_COLUMNS: AllColumns = (
@@ -22,6 +24,7 @@ pub(crate) const ALL_COLUMNS: AllColumns = (
     janus_backend::created_at,
     janus_backend::capacity,
     janus_backend::balancer_capacity,
+    janus_backend::api_version,
 );
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -35,6 +38,7 @@ pub(crate) struct Object {
     created_at: DateTime<Utc>,
     capacity: Option<i32>,
     balancer_capacity: Option<i32>,
+    api_version: String,
 }
 
 impl Object {
@@ -129,6 +133,7 @@ pub(crate) struct UpsertQuery<'a> {
     session_id: i64,
     capacity: Option<i32>,
     balancer_capacity: Option<i32>,
+    api_version: String,
 }
 
 impl<'a> UpsertQuery<'a> {
@@ -139,6 +144,7 @@ impl<'a> UpsertQuery<'a> {
             session_id,
             capacity: None,
             balancer_capacity: None,
+            api_version: JANUS_API_VERSION.to_string(),
         }
     }
 
@@ -236,17 +242,19 @@ const MOST_LOADED_SQL: &str = r#"
     LEFT JOIN room AS r2
     ON 1 = 1
     WHERE r2.id = $1
-    AND   COALESCE(jb.balancer_capacity, jb.capacity, 2147483647) - COALESCE(jbl.load, 0) >= COALESCE(r2.reserve, 0)
+    AND   COALESCE(jb.balancer_capacity, jb.capacity, 2147483647) - COALESCE(jbl.load, 0) >= COALESCE(r2.reserve, 1)
+    AND   jb.api_version = $2
     ORDER BY COALESCE(jbl.load, 0) DESC
     LIMIT 1
 "#;
 
 pub(crate) fn most_loaded(room_id: Uuid, conn: &PgConnection) -> Result<Option<Object>, Error> {
     use diesel::prelude::*;
-    use diesel::sql_types::Uuid;
+    use diesel::sql_types::{Text, Uuid};
 
     diesel::sql_query(MOST_LOADED_SQL)
         .bind::<Uuid, _>(room_id)
+        .bind::<Text, _>(JANUS_API_VERSION)
         .get_result(conn)
         .optional()
 }
@@ -293,16 +301,18 @@ const LEAST_LOADED_SQL: &str = r#"
     LEFT JOIN room AS r2
     ON 1 = 1
     WHERE r2.id = $1
+    AND   jb.api_version = $2
     ORDER BY COALESCE(jb.balancer_capacity, jb.capacity, 2147483647) - COALESCE(jbl.load, 0) DESC
     LIMIT 1
 "#;
 
 pub(crate) fn least_loaded(room_id: Uuid, conn: &PgConnection) -> Result<Option<Object>, Error> {
     use diesel::prelude::*;
-    use diesel::sql_types::Uuid;
+    use diesel::sql_types::{Text, Uuid};
 
     diesel::sql_query(LEAST_LOADED_SQL)
         .bind::<Uuid, _>(room_id)
+        .bind::<Text, _>(JANUS_API_VERSION)
         .get_result(conn)
         .optional()
 }

src/schema.rs

@@ -33,6 +33,7 @@ table! {
         created_at -> Timestamptz,
         capacity -> Nullable<Int4>,
         balancer_capacity -> Nullable<Int4>,
+        api_version -> Text,
     }
 }