changes

crates/config/tests/loader/layering_test.rs

@@ -0,0 +1,138 @@
+use figment::Jail;
+
+use config::{MediaBackend, load};
+
+const CONFIG_FILE: &str = "config.toml";
+
+#[test]
+fn with_no_file_and_no_environment_every_default_stands() {
+    Jail::expect_with(|_jail| {
+        let loaded = load().unwrap();
+
+        assert_eq!(loaded.server.port, 3000);
+        assert_eq!(loaded.server.host, "0.0.0.0");
+        assert_eq!(loaded.storage.data_dir, "./data");
+        assert!(loaded.auth.jwt_secret.is_none());
+        Ok(())
+    });
+}
+
+#[test]
+fn a_file_overrides_the_defaults_it_names() {
+    Jail::expect_with(|jail| {
+        jail.create_file(CONFIG_FILE, "[server]\nport = 4321\n")?;
+
+        let loaded = load().unwrap();
+
+        assert_eq!(loaded.server.port, 4321);
+        assert_eq!(loaded.server.host, "0.0.0.0");
+        Ok(())
+    });
+}
+
+#[test]
+fn the_environment_overrides_the_file() {
+    Jail::expect_with(|jail| {
+        jail.create_file(CONFIG_FILE, "[server]\nport = 4321\nhost = \"127.0.0.1\"\n")?;
+        jail.set_env("KMOOD_SERVER__PORT", "8080");
+
+        let loaded = load().unwrap();
+
+        assert_eq!(loaded.server.port, 8080);
+        assert_eq!(loaded.server.host, "127.0.0.1");
+        Ok(())
+    });
+}
+
+#[test]
+fn a_double_underscore_descends_a_section() {
+    Jail::expect_with(|jail| {
+        jail.set_env("KMOOD_SERVER__CORS__ALLOW_ANY_ORIGIN", "false");
+
+        let loaded = load().unwrap();
+
+        assert!(!loaded.server.cors.allow_any_origin);
+        Ok(())
+    });
+}
+
+#[test]
+fn a_single_underscore_stays_inside_a_field_name() {
+    Jail::expect_with(|jail| {
+        jail.set_env("KMOOD_STORAGE__DATA_DIR", "/var/lib/kmood");
+        jail.set_env("KMOOD_AUTH__JWT_SECRET", "from-the-environment");
+
+        let loaded = load().unwrap();
+
+        assert_eq!(loaded.storage.data_dir, "/var/lib/kmood");
+        assert_eq!(
+            loaded.auth.jwt_secret.as_deref(),
+            Some("from-the-environment")
+        );
+        Ok(())
+    });
+}
+
+#[test]
+fn the_environment_can_switch_the_media_backend() {
+    Jail::expect_with(|jail| {
+        jail.set_env("KMOOD_STORAGE__MEDIA__BACKEND", "s3");
+        jail.set_env("KMOOD_STORAGE__MEDIA__BUCKET", "moods");
+        jail.set_env("KMOOD_STORAGE__MEDIA__REGION", "eu-central-1");
+
+        let loaded = load().unwrap();
+
+        match loaded.storage.media {
+            MediaBackend::S3 { bucket, region, .. } => {
+                assert_eq!(bucket, "moods");
+                assert_eq!(region, "eu-central-1");
+            }
+            other => panic!("expected the s3 backend, got {other:?}"),
+        }
+        Ok(())
+    });
+}
+
+#[test]
+fn an_unrelated_variable_leaves_the_configuration_alone() {
+    Jail::expect_with(|jail| {
+        jail.set_env("PORT", "9999");
+        jail.set_env("SERVER__PORT", "9999");
+
+        let loaded = load().unwrap();
+
+        assert_eq!(loaded.server.port, 3000);
+        Ok(())
+    });
+}
+
+#[test]
+fn a_list_arrives_as_an_array() {
+    Jail::expect_with(|jail| {
+        jail.set_env(
+            "KMOOD_SERVER__CORS__ALLOWED_ORIGINS",
+            r#"["https://a.example","https://b.example"]"#,
+        );
+
+        let loaded = load().unwrap();
+
+        assert_eq!(
+            loaded.server.cors.allowed_origins,
+            vec!["https://a.example", "https://b.example"]
+        );
+        Ok(())
+    });
+}
+
+#[test]
+fn the_file_to_read_can_be_named_by_the_environment() {
+    Jail::expect_with(|jail| {
+        jail.create_file("elsewhere.toml", "[server]\nport = 7777\n")?;
+        jail.set_env("KMOOD_CONFIG_FILE", "elsewhere.toml");
+
+        let loaded = load().unwrap();
+
+        assert_eq!(loaded.server.port, 7777);
+        Ok(())
+    });
+}

crates/config/tests/loader/rejection_test.rs

@@ -0,0 +1,47 @@
+use figment::Jail;
+
+use config::load;
+
+const CONFIG_FILE: &str = "config.toml";
+
+#[test]
+fn a_malformed_file_is_refused_rather_than_ignored() {
+    Jail::expect_with(|jail| {
+        jail.create_file(CONFIG_FILE, "[server\nport = ")?;
+
+        assert!(load().is_err());
+        Ok(())
+    });
+}
+
+#[test]
+fn a_value_of_the_wrong_type_is_refused() {
+    Jail::expect_with(|jail| {
+        jail.set_env("KMOOD_SERVER__PORT", "not-a-port");
+
+        assert!(load().is_err());
+        Ok(())
+    });
+}
+
+#[test]
+fn a_refusal_names_the_key_at_fault() {
+    Jail::expect_with(|jail| {
+        jail.set_env("KMOOD_SERVER__PORT", "not-a-port");
+
+        let message = load().unwrap_err().to_string().to_lowercase();
+
+        assert!(message.contains("port"), "unhelpful message: {message}");
+        Ok(())
+    });
+}
+
+#[test]
+fn a_named_file_that_is_missing_is_refused_rather_than_ignored() {
+    Jail::expect_with(|jail| {
+        jail.set_env("KMOOD_CONFIG_FILE", "nowhere.toml");
+
+        assert!(load().is_err());
+        Ok(())
+    });
+}