v0.1.2-pre.002

crates/ksp-logging-lib/src/settings.rs

@@ -0,0 +1,233 @@
+// file: crates/ksp-logging-lib/src/settings.rs
+// version: 1
+
+/// Runtime filter level used by KSP logging settings.
+#[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
+pub enum LogFilterLevel {
+    /// Disables matching logging events and spans.
+    Off,
+    /// Enables only error-level events and spans.
+    Error,
+    /// Enables warning and error events and spans.
+    Warn,
+    /// Enables informational, warning and error events and spans.
+    Info,
+    /// Enables debug and less verbose events and spans.
+    Debug,
+    /// Enables all KSP logging events and spans.
+    Trace,
+}
+
+/// Per-target filter override owned by Logging.
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct TargetFilter {
+    target_prefix: std::string::String,
+    level: crate::LogFilterLevel,
+}
+
+impl TargetFilter {
+    /// Creates a filter override for a KSP target prefix.
+    #[must_use]
+    pub fn new(target_prefix: impl std::convert::Into<std::string::String>, level: crate::LogFilterLevel) -> Self {
+        return Self { target_prefix: target_prefix.into(), level };
+    }
+
+    /// Returns the configured target prefix.
+    #[must_use]
+    pub fn target_prefix(&self) -> &str {
+        return self.target_prefix.as_str();
+    }
+
+    /// Returns the configured filter level.
+    #[must_use]
+    pub const fn level(&self) -> crate::LogFilterLevel {
+        return self.level;
+    }
+}
+
+/// Lifecycle events emitted for spans by the formatted subscriber.
+#[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
+pub enum SpanEvents {
+    /// Does not synthesize span lifecycle events.
+    Off,
+    /// Emits span creation and closure events for timing-oriented diagnostics.
+    NewAndClose,
+    /// Emits all supported span lifecycle events.
+    Full,
+}
+
+/// Console stream selected for human-readable logs.
+#[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
+pub enum ConsoleOutput {
+    /// Writes console logs to standard output.
+    Stdout,
+    /// Writes console logs to standard error.
+    Stderr,
+}
+
+/// Runtime settings for the optional console output.
+#[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
+pub struct ConsoleSettings {
+    output: crate::ConsoleOutput,
+}
+
+impl ConsoleSettings {
+    /// Creates console settings targeting standard output.
+    #[must_use]
+    pub const fn stdout() -> Self {
+        return Self { output: crate::ConsoleOutput::Stdout };
+    }
+
+    /// Creates console settings targeting standard error.
+    #[must_use]
+    pub const fn stderr() -> Self {
+        return Self { output: crate::ConsoleOutput::Stderr };
+    }
+
+    /// Returns the selected console stream.
+    #[must_use]
+    pub const fn output(&self) -> crate::ConsoleOutput {
+        return self.output;
+    }
+}
+
+/// Rotation cadence for the optional file output.
+#[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
+pub enum FileRotation {
+    /// Keeps a single non-rotating file.
+    Never,
+    /// Rotates the file every hour.
+    Hourly,
+    /// Rotates the file every day.
+    Daily,
+}
+
+/// Runtime settings for the optional file output.
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct FileSettings {
+    directory: std::path::PathBuf,
+    file_name_prefix: std::string::String,
+    rotation: crate::FileRotation,
+}
+
+impl FileSettings {
+    /// Creates file output settings.
+    #[must_use]
+    pub fn new(
+        directory: impl std::convert::Into<std::path::PathBuf>,
+        file_name_prefix: impl std::convert::Into<std::string::String>,
+        rotation: crate::FileRotation,
+    ) -> Self {
+        return Self { directory: directory.into(), file_name_prefix: file_name_prefix.into(), rotation };
+    }
+
+    /// Returns the directory containing log files.
+    #[must_use]
+    pub fn directory(&self) -> &std::path::Path {
+        return self.directory.as_path();
+    }
+
+    /// Returns the file-name prefix passed to the file appender.
+    #[must_use]
+    pub fn file_name_prefix(&self) -> &str {
+        return self.file_name_prefix.as_str();
+    }
+
+    /// Returns the selected file rotation cadence.
+    #[must_use]
+    pub const fn rotation(&self) -> crate::FileRotation {
+        return self.rotation;
+    }
+}
+
+/// Complete runtime settings consumed by `ksp-logging-lib` initialization and reload.
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct LoggingSettings {
+    default_filter: crate::LogFilterLevel,
+    target_filters: std::vec::Vec<crate::TargetFilter>,
+    span_events: crate::SpanEvents,
+    console: std::option::Option<crate::ConsoleSettings>,
+    file: std::option::Option<crate::FileSettings>,
+}
+
+impl LoggingSettings {
+    /// Creates explicit Logging settings without any target override.
+    #[must_use]
+    pub fn new(
+        default_filter: crate::LogFilterLevel,
+        span_events: crate::SpanEvents,
+        console: std::option::Option<crate::ConsoleSettings>,
+        file: std::option::Option<crate::FileSettings>,
+    ) -> Self {
+        return Self { default_filter, target_filters: std::vec::Vec::new(), span_events, console, file };
+    }
+
+    /// Adds one target-prefix override and returns the updated settings.
+    #[must_use]
+    pub fn with_target_filter(mut self, target_filter: crate::TargetFilter) -> Self {
+        self.target_filters.push(target_filter);
+        return self;
+    }
+
+    /// Returns the default level applied to KSP-owned targets.
+    #[must_use]
+    pub const fn default_filter(&self) -> crate::LogFilterLevel {
+        return self.default_filter;
+    }
+
+    /// Returns target-prefix overrides in insertion order.
+    #[must_use]
+    pub fn target_filters(&self) -> &[crate::TargetFilter] {
+        return self.target_filters.as_slice();
+    }
+
+    /// Returns the selected span lifecycle event policy.
+    #[must_use]
+    pub const fn span_events(&self) -> crate::SpanEvents {
+        return self.span_events;
+    }
+
+    /// Returns console settings when console output is enabled.
+    #[must_use]
+    pub fn console(&self) -> std::option::Option<&crate::ConsoleSettings> {
+        return self.console.as_ref();
+    }
+
+    /// Returns file settings when file output is enabled.
+    #[must_use]
+    pub fn file(&self) -> std::option::Option<&crate::FileSettings> {
+        return self.file.as_ref();
+    }
+
+    /// Validates backend-independent invariants of the runtime settings.
+    pub fn validate(&self) -> ksp_core_lib::Result<()> {
+        for target_filter in &self.target_filters {
+            if target_filter.target_prefix().is_empty() {
+                return std::result::Result::Err(
+                    ksp_core_lib::Error::new(crate::ERROR_CODE_INVALID_SETTINGS, "target filter prefix must not be empty")
+                        .with_context("field", "target_filters.target_prefix"),
+                );
+            }
+            if !target_filter.target_prefix().starts_with("ksp-") {
+                return std::result::Result::Err(
+                    ksp_core_lib::Error::new(crate::ERROR_CODE_INVALID_SETTINGS, "target filter prefix must identify a KSP-owned target")
+                        .with_context("field", "target_filters.target_prefix")
+                        .with_context("target_prefix", target_filter.target_prefix()),
+                );
+            }
+        }
+        if let std::option::Option::Some(file) = self.file.as_ref() {
+            if file.file_name_prefix().is_empty() {
+                return std::result::Result::Err(
+                    ksp_core_lib::Error::new(crate::ERROR_CODE_INVALID_SETTINGS, "file name prefix must not be empty")
+                        .with_context("field", "file.file_name_prefix"),
+                );
+            }
+        }
+        return std::result::Result::Ok(());
+    }
+}
+
+#[cfg(test)]
+#[path = "../unit_tests/settings.rs"]
+mod tests;