Properly configure changed optional dependencies (#1144)

* add logic to accept optional dependency list and determine dependencies based on new service configurations

* add debugs

* properly extend iterator

system-images/compat/src/config/mod.rs

@@ -1,10 +1,12 @@
 use std::borrow::Cow;
-use std::collections::BTreeMap;
+use std::collections::{BTreeMap, BTreeSet, HashMap};
 use std::path::Path;
 
 use beau_collector::BeauCollector;
 use embassy::config::action::SetResult;
 use embassy::config::{spec, Config};
+use embassy::s9pk::manifest::PackageId;
+use embassy::status::health_check::HealthCheckId;
 use linear_map::LinearMap;
 
 pub mod rules;
@@ -12,15 +14,39 @@ pub mod rules;
 use anyhow::anyhow;
 pub use rules::{ConfigRuleEntry, ConfigRuleEntryWithSuggestions};
 
+use self::rules::ConfigRule;
+pub type DepInfo = HashMap<PackageId, DepRuleInfo>;
+#[derive(Clone, Debug, serde::Deserialize)]
+pub struct DepRuleInfo {
+    condition: ConfigRule,
+    health_checks: BTreeSet<HealthCheckId>,
+}
+
 pub fn validate_configuration(
     name: &str,
     config: Config,
     rules_path: &Path,
     config_path: &Path,
+    maybe_deps_path: Option<&str>,
 ) -> Result<SetResult, anyhow::Error> {
     let rules: Vec<ConfigRuleEntry> = serde_yaml::from_reader(std::fs::File::open(rules_path)?)?;
     let mut cfgs = LinearMap::new();
     cfgs.insert(name, Cow::Borrowed(&config));
+
+    let mut depends_on = BTreeMap::new();
+    if let Some(deps_path) = maybe_deps_path.map(Path::new) {
+        if deps_path.exists() {
+            let deps: DepInfo = serde_yaml::from_reader(std::fs::File::open(deps_path)?)?;
+            // check if new config is set to depend on any optional dependencies
+            depends_on.extend(
+                deps.into_iter()
+                    .filter(|(_, data)| (data.condition.compiled)(&config, &cfgs))
+                    .map(|(pkg_id, data)| (pkg_id, data.health_checks)),
+            );
+        };
+    }
+
+    // check that all configuration rules
     let rule_check = rules
         .into_iter()
         .map(|r| r.check(&config, &cfgs))
@@ -35,7 +61,7 @@ pub fn validate_configuration(
             std::fs::rename(config_path.with_extension("tmp"), config_path)?;
             // return set result
             Ok(SetResult {
-                depends_on: BTreeMap::new(),
+                depends_on,
                 // sending sigterm so service is restarted - in 0.3.x services, this is whatever signal is needed to send to the process to pick up the configuration
                 signal: Some(nix::sys::signal::SIGTERM),
             })