MULTI-314: Add canary promotion

src/adapters/ingresses/apig.rs

@@ -184,6 +184,38 @@ impl AwsApiGateway {
 
         Ok(())
     }
+
+    pub async fn promote_apig_canary(&self, api_name: &str, stage_name: &str) -> Result<()> {
+        let api = self.get_api_id_by_name(api_name).await?;
+
+        // Overwrite the main deployment's ID with the canary's
+        let replace_deployment_op = PatchOperation::builder()
+            .op(Op::Copy)
+            .from("/canarySettings/deploymentId")
+            .path("/deploymentId")
+            .build();
+
+        // Reset canary traffic to 0% so we're ready for another release
+        let reset_traffic_op = PatchOperation::builder()
+            .op(Op::Replace)
+            .path("/canarySettings/percentTraffic")
+            // Note: this must be a string to pass into Value, but it's actually an f64 in AWS
+            .value("0.0")
+            .build();
+
+        // Send request to update stage
+        self.apig_client
+            .update_stage()
+            .rest_api_id(api.id.unwrap_or_default())
+            .stage_name(stage_name)
+            .patch_operations(replace_deployment_op)
+            .patch_operations(reset_traffic_op)
+            .send()
+            .await
+            .into_diagnostic()?;
+
+        Ok(())
+    }
 }
 
 /// given a path to a file, load it as an array of bytes.
@@ -228,4 +260,10 @@ impl Ingress for AwsApiGateway {
 
         Ok(())
     }
+
+    async fn promote_canary(&mut self) -> Result<()> {
+        self.promote_apig_canary("Releases", "prod").await?;
+
+        Ok(())
+    }
 }

src/adapters/ingresses/mod.rs

@@ -16,6 +16,9 @@ pub trait Ingress {
     async fn rollback_canary(&mut self) -> Result<()>;
     // async fn promote_canary(&mut self) -> Result<()>;
     async fn set_canary_traffic(&mut self, percent: WholePercent) -> Result<()>;
+    // async fn yank_canary(&mut self) -> Result<()>;
+    async fn promote_canary(&mut self) -> Result<()>;
+    // async fn set_canary_traffic(&mut self, percent: u8);
 }
 
 pub struct MockIngress;
@@ -33,6 +36,10 @@ impl Ingress for MockIngress {
     async fn rollback_canary(&mut self) -> Result<()> {
         todo!()
     }
+
+    async fn promote_canary(&mut self) -> Result<()> {
+        todo!()
+    }
 }
 
 impl From<MockIngress> for BoxIngress {