Add canary traffic changing

src/adapters/ingresses/apig.rs

@@ -1,9 +1,11 @@
 use std::path::PathBuf;
 
 use crate::utils::load_default_aws_config;
+use crate::WholePercent;
 
 use super::Ingress;
 use async_trait::async_trait;
+use aws_sdk_apigateway::types::{Op, PatchOperation};
 use miette::miette;
 use miette::{IntoDiagnostic, Result};
 use tokio::{fs::File, io::AsyncReadExt};
@@ -73,7 +75,7 @@ impl AwsApiGateway {
         stage_name: &str,
         lambda_name: &str,
         lambda_version: &str,
-        traffic_percentage: f64,
+        traffic_percentage: WholePercent,
     ) -> Result<()> {
         // Update the APIG with the new lambda version
         self.apig_client
@@ -94,8 +96,7 @@ impl AwsApiGateway {
             .stage_name(stage_name)
             .canary_settings(
                 DeploymentCanarySettings::builder()
-                    .percent_traffic(traffic_percentage)
-                    .use_stage_cache(false)
+                    .percent_traffic(traffic_percentage.into_inner() as f64)
                     .build(),
             )
             .send()
@@ -104,6 +105,30 @@ impl AwsApiGateway {
 
         Ok(())
     }
+
+    pub async fn update_canary_traffic(
+        &self,
+        api_id: &str,
+        stage_name: &str,
+        traffic_percentage: WholePercent,
+    ) -> Result<()> {
+        let patch_op = PatchOperation::builder()
+            .op(Op::Replace)
+            .path("/canarySettings/percentTraffic")
+            .value(traffic_percentage.to_string())
+            .build();
+
+        self.apig_client
+            .update_stage()
+            .rest_api_id(api_id)
+            .stage_name(stage_name)
+            .patch_operations(patch_op)
+            .send()
+            .await
+            .into_diagnostic()?;
+
+        Ok(())
+    }
 }
 
 /// given a path to a file, load it as an array of bytes.
@@ -123,7 +148,20 @@ impl Ingress for AwsApiGateway {
 
         // Next, we need to create a new deployment, pointing at our
         // new lambda version with canary settings
-        self.create_apig_deployment("Releases", "prod", "releases", &lambda_version, 0.0)
+        self.create_apig_deployment(
+            "Releases",
+            "prod",
+            "releases",
+            &lambda_version,
+            WholePercent::try_new(0).into_diagnostic()?,
+        )
+        .await?;
+
+        Ok(())
+    }
+
+    async fn set_canary_traffic(&mut self, percent: WholePercent) -> Result<()> {
+        self.update_canary_traffic("Releases", "prod", percent)
             .await?;
 
         Ok(())

src/adapters/ingresses/mod.rs

@@ -1,6 +1,8 @@
 use async_trait::async_trait;
 use miette::Result;
 
+use crate::WholePercent;
+
 /// Ingresses are responsible for (1) controlling how much traffic the canary
 /// gets (hence the name ingress, since it functions like a virtual LB) and
 /// (2) deploying, yanking, and promoting both the canary and the baseline.
@@ -12,7 +14,7 @@ pub trait Ingress {
     // TODO: define the other methods on this type.
     // async fn yank_canary(&mut self) -> Result<()>;
     // async fn promote_canary(&mut self) -> Result<()>;
-    // async fn set_canary_traffic(&mut self, percent: u8);
+    async fn set_canary_traffic(&mut self, percent: WholePercent) -> Result<()>;
 }
 
 pub struct MockIngress;
@@ -22,6 +24,10 @@ impl Ingress for MockIngress {
     async fn deploy(&mut self) -> Result<()> {
         todo!()
     }
+
+    async fn set_canary_traffic(&mut self, _percent: WholePercent) -> Result<()> {
+        todo!()
+    }
 }
 
 impl From<MockIngress> for BoxIngress {

src/lib.rs

@@ -1,5 +1,6 @@
 pub use config::Flags;
 pub use pipeline::Pipeline;
+pub(crate) use pipeline::WholePercent;
 
 /// An adapter connects to some observable resource (like `CloudWatch`) and
 /// emits events, like failed and succeeded requests.

src/pipeline/mod.rs

@@ -7,6 +7,8 @@ use crate::{
 use bon::bon;
 use miette::Result;
 
+pub(crate) use percent::WholePercent;
+
 /// An alias for the Response Code-based monitor.
 pub type ResponseMonitor = Box<dyn Monitor<Item = CategoricalObservation<5, ResponseStatusCode>>>;
 

src/pipeline/percent.rs

@@ -22,11 +22,11 @@ impl DecimalPercent {
     validate(less_or_equal = 100),
     derive(Debug, Display, Copy, Clone, PartialEq, Eq, TryFrom, Into)
 )]
-pub(super) struct WholePercent(u8);
+pub(crate) struct WholePercent(u8);
 
 impl WholePercent {
     /// returns "the rest" of the whole. That is, `100 - this value`.
-    pub(super) fn inverse(self) -> Self {
+    pub(crate) fn inverse(self) -> Self {
         let val = u8::from(self);
         Self::try_from(100 - val).unwrap()
     }