migrations: Add migrations for settings.dns

This adds the migrations needed for `settings.dns`, one for the setting,
its service and configuration file, and one for the setting metadata.

Release.toml

@@ -142,3 +142,7 @@ version = "1.9.2"
 ]
 "(1.9.0, 1.9.1)" = []
 "(1.9.1, 1.9.2)" = []
+"(1.9.2, 1.10.0)" = [
+    "migrate_v1.10.0_dns-settings.lz4",
+    "migrate_v1.10.0_dns-settings-metadata.lz4",
+]

sources/Cargo.toml

@@ -25,7 +25,8 @@ members = [
     "api/prairiedog",
 
     # "api/migration/migrations/vX.Y.Z/..."
-    # (all migrations currently archived; replace this line with new ones)
+    "api/migration/migrations/v1.10.0/dns-settings",
+    "api/migration/migrations/v1.10.0/dns-settings-metadata",
 
     "bottlerocket-release",
 

sources/api/migration/migrations/v1.10.0/dns-settings-metadata/Cargo.toml

@@ -0,0 +1,9 @@
+[package]
+name = "dns-settings-metadata"
+version = "0.1.0"
+license = "Apache-2.0 OR MIT"
+edition = "2018"
+publish = false
+
+[dependencies]
+migration-helpers = { path = "../../../migration-helpers", version = "0.1.0"}

sources/api/migration/migrations/v1.10.0/dns-settings-metadata/src/main.rs

@@ -0,0 +1,23 @@
+#![deny(rust_2018_idioms)]
+
+use migration_helpers::common_migrations::{AddMetadataMigration, SettingMetadata};
+use migration_helpers::{migrate, Result};
+use std::process;
+
+/// We added a new setting and `affected-services` metadata for `settings.dns`
+fn run() -> Result<()> {
+    migrate(AddMetadataMigration(&[SettingMetadata {
+        metadata: &["affected-services"],
+        setting: "settings.dns",
+    }]))
+}
+
+// Returning a Result from main makes it print a Debug representation of the error, but with Snafu
+// we have nice Display representations of the error, so we wrap "main" (run) and print any error.
+// /~https://github.com/shepmaster/snafu/issues/110
+fn main() {
+    if let Err(e) = run() {
+        eprintln!("{}", e);
+        process::exit(1);
+    }
+}

sources/api/migration/migrations/v1.10.0/dns-settings/Cargo.toml

@@ -0,0 +1,9 @@
+[package]
+name = "dns-settings"
+version = "0.1.0"
+license = "Apache-2.0 OR MIT"
+edition = "2018"
+publish = false
+
+[dependencies]
+migration-helpers = { path = "../../../migration-helpers", version = "0.1.0"}

sources/api/migration/migrations/v1.10.0/dns-settings/src/main.rs

@@ -0,0 +1,24 @@
+#![deny(rust_2018_idioms)]
+
+use migration_helpers::common_migrations::AddPrefixesMigration;
+use migration_helpers::{migrate, Result};
+use std::process;
+
+/// We added new settings under `settings.dns` for configuring /etc/resolv.conf
+fn run() -> Result<()> {
+    migrate(AddPrefixesMigration(vec![
+        "settings.dns",
+        "services.dns",
+        "configuration-files.netdog-toml",
+    ]))
+}
+
+// Returning a Result from main makes it print a Debug representation of the error, but with Snafu
+// we have nice Display representations of the error, so we wrap "main" (run) and print any error.
+// /~https://github.com/shepmaster/snafu/issues/110
+fn main() {
+    if let Err(e) = run() {
+        eprintln!("{}", e);
+        process::exit(1);
+    }
+}