refactor: Reduce cognitive complexity of WebhookNotification handler. 1/2

Closes kemitix/git-next#49

Cargo.toml

@@ -3,7 +3,8 @@ resolver = "2"
 members = ["crates/*"]
 
 [workspace.package]
-version = "0.10.0"
+version = "0.10.0" # Update git-next-* under workspace.dependencies
+
 edition = "2021"
 license = "MIT"
 repository = "https://git.kemitix.net/kemitix/git-next"

crates/repo-actor/src/handlers/webhook_notification.rs

@@ -1,41 +1,24 @@
 //
 use actix::prelude::*;
 
-use crate::{self as actor, messages::WebhookNotification};
-use git_next_config as config;
-use git_next_git as git;
+use crate::{self as actor, messages::WebhookNotification, RepoActorLog};
+use git_next_config::webhook::push::Branch;
+use git_next_config::WebhookAuth;
+use git_next_git::{self as git, ForgeLike};
 
 use tracing::{info, warn};
 
 impl Handler<WebhookNotification> for actor::RepoActor {
     type Result = ();
 
-    #[allow(clippy::cognitive_complexity)] // TODO: (#49) reduce complexity
     #[tracing::instrument(name = "RepoActor::WebhookMessage", skip_all, fields(token = %self.message_token, repo = %self.repo_details))]
     fn handle(&mut self, msg: WebhookNotification, ctx: &mut Self::Context) -> Self::Result {
-        let Some(expected_authorization) = &self.webhook_auth else {
-            actor::logger(&self.log, "server has no auth token");
-            warn!("Don't know what authorization to expect");
-            return;
-        };
         let Some(config) = &self.repo_details.repo_config else {
             actor::logger(&self.log, "server has no repo config");
             warn!("No repo config");
             return;
         };
-        if !self
-            .forge
-            .is_message_authorised(&msg, expected_authorization)
-        {
-            actor::logger(&self.log, "message authorisation is invalid");
-            warn!(
-                "Invalid authorization - expected {}",
-                expected_authorization
-            );
-            return;
-        }
-        if self.forge.should_ignore_message(&msg) {
-            actor::logger(&self.log, "forge sent ignorable message");
+        if validate_notification(&msg, &self.webhook_auth, &*self.forge, &self.log).is_err() {
             return;
         }
         let body = msg.body();
@@ -54,7 +37,7 @@ impl Handler<WebhookNotification> for actor::RepoActor {
                     );
                     return;
                 }
-                Some(config::webhook::push::Branch::Main) => {
+                Some(Branch::Main) => {
                     actor::logger(&self.log, "message is for main branch");
                     let commit = git::Commit::from(push);
                     if self.last_main_commit.as_ref() == Some(&commit) {
@@ -68,7 +51,7 @@ impl Handler<WebhookNotification> for actor::RepoActor {
                     }
                     self.last_main_commit.replace(commit);
                 }
-                Some(config::webhook::push::Branch::Next) => {
+                Some(Branch::Next) => {
                     actor::logger(&self.log, "message is for next branch");
                     let commit = git::Commit::from(push);
                     if self.last_next_commit.as_ref() == Some(&commit) {
@@ -82,7 +65,7 @@ impl Handler<WebhookNotification> for actor::RepoActor {
                     }
                     self.last_next_commit.replace(commit);
                 }
-                Some(config::webhook::push::Branch::Dev) => {
+                Some(Branch::Dev) => {
                     actor::logger(&self.log, "message is for dev branch");
                     let commit = git::Commit::from(push);
                     if self.last_dev_commit.as_ref() == Some(&commit) {
@@ -110,3 +93,30 @@ impl Handler<WebhookNotification> for actor::RepoActor {
         );
     }
 }
+
+fn validate_notification(
+    msg: &WebhookNotification,
+    webhook_auth: &Option<WebhookAuth>,
+    forge: &dyn ForgeLike,
+    log: &Option<RepoActorLog>,
+) -> Result<(), ()> {
+    let Some(expected_authorization) = webhook_auth else {
+        actor::logger(log, "server has no auth token");
+        warn!("Don't know what authorization to expect");
+        return Err(());
+    };
+
+    if !forge.is_message_authorised(msg, expected_authorization) {
+        actor::logger(log, "message authorisation is invalid");
+        warn!(
+            "Invalid authorization - expected {}",
+            expected_authorization
+        );
+        return Err(());
+    }
+    if forge.should_ignore_message(msg) {
+        actor::logger(log, "forge sent ignorable message");
+        return Err(());
+    }
+    Ok(())
+}