Merge pull request #3365 from lightpanda-io/log-notes

log: allow 'note' to be silenced, log CLI tips

src/log.zig

@@ -34,6 +34,7 @@ pub const Scope = enum {
     http,
     js,
     mcp,
+    note,
     not_implemented,
     scheduler,
     storage,
@@ -178,6 +179,19 @@ pub fn warnDisabledIFrame() void {
 }
 
 pub fn log(scope: Scope, level: Level, msg: []const u8, data: anytype) void {
+    var kvs: [@typeInfo(@TypeOf(data)).@"struct".fields.len]KV = undefined;
+    initKVs(data, &kvs);
+    logKVs(scope, level, msg, &kvs);
+}
+
+inline fn initKVs(data: anytype, kvs: []KV) void {
+    inline for (@typeInfo(@TypeOf(data)).@"struct".fields, 0..) |f, i| {
+        const value = @field(data, f.name);
+        kvs[i] = .{ .key = f.name, .value = Value.init(&value) };
+    }
+}
+
+pub fn logKVs(scope: Scope, level: Level, msg: []const u8, kvs: []const KV) void {
     if (enabled(scope, level) == false) {
         return;
     }
@@ -193,7 +207,7 @@ pub fn log(scope: Scope, level: Level, msg: []const u8, data: anytype) void {
     if (sink) |s| {
         var buf: [4096]u8 = undefined;
         var w: std.Io.Writer = .fixed(&buf);
-        logTo(scope, level, msg, data, &w) catch |log_err| {
+        logToErased(scope, level, msg, kvs, &w) catch |log_err| {
             std.debug.print("$time={d} $level=fatal $scope={s} $msg=\"log err\" err={s} log_msg=\"{s}\"\n", .{ timestamp(.real), @tagName(scope), @errorName(log_err), msg });
             return;
         };
@@ -205,20 +219,16 @@ pub fn log(scope: Scope, level: Level, msg: []const u8, data: anytype) void {
     const stderr = std.debug.lockStderr(&buf);
     defer std.debug.unlockStderr();
 
-    logTo(scope, level, msg, data, &stderr.file_writer.interface) catch |log_err| {
-        std.debug.print("$time={d} $level=fatal $scope={s} $msg=\"log err\" err={s} log_msg=\"{s}\"\n", .{ timestamp(.real), @errorName(log_err), @tagName(scope), msg });
+    logToErased(scope, level, msg, kvs, &stderr.file_writer.interface) catch |log_err| {
+        std.debug.print("$time={d} $level=fatal $scope={s} $msg=\"log err\" err={s} log_msg=\"{s}\"\n", .{ timestamp(.real), @tagName(scope), @errorName(log_err), msg });
     };
 }
 
-// Converts each field of `data` into a runtime Value so that a single copy of
-// the formatting code (logToErased and below) can do the actual writing.
+// Like `log`, but to an explicit writer and without the enabled/sink
+// gating. Only used by tests.
 fn logTo(scope: Scope, level: Level, msg: []const u8, data: anytype, out: *std.Io.Writer) !void {
-    const fields = @typeInfo(@TypeOf(data)).@"struct".fields;
-    var kvs: [fields.len]KV = undefined;
-    inline for (fields, 0..) |f, i| {
-        const value = @field(data, f.name);
-        kvs[i] = .{ .key = f.name, .value = Value.init(&value) };
-    }
+    var kvs: [@typeInfo(@TypeOf(data)).@"struct".fields.len]KV = undefined;
+    initKVs(data, &kvs);
     return logToErased(scope, level, msg, &kvs, out);
 }
 
@@ -320,9 +330,18 @@ fn logPrettyPrefix(scope: Scope, level: Level, msg: []const u8, writer: *std.Io.
     }
 }
 
-const KV = struct {
+pub const KV = struct {
     key: []const u8,
     value: Value,
+
+    // `vp` is a pointer, as with Value.init. A string literal is already one;
+    // for anything else pass `&value` and keep it alive until the log call.
+    pub fn init(key: []const u8, vp: anytype) KV {
+        return .{
+            .key = key,
+            .value = .init(vp),
+        };
+    }
 };
 
 const Value = union(enum) {

src/main.zig

@@ -94,6 +94,8 @@ fn run(allocator: Allocator, main_arena: Allocator, proc_args: std.process.Args)
 
     app.telemetry.record(.{ .run = {} });
 
+    logConfigTips(app.config);
+
     defer if (app.config.dumpMetricsOnExit()) {
         var writer = std.Io.File.stdout().writerStreaming(lp.io, &.{});
         lp.metrics.write(&writer.interface);
@@ -396,3 +398,17 @@ fn mcpThread(allocator: std.mem.Allocator, app: *App, cdp_server: ?*lp.Server, e
         log.fatal(.mcp, "mcp error", .{ .err = err });
     };
 }
+
+fn logConfigTips(config: *const Config) void {
+    var count: usize = 0;
+    var tips: [2]log.KV = undefined;
+    if (config.obeyRobots() == false) {
+        tips[count] = .init("robots", "use '--obey-robots' to use a sites robots.txt");
+        count += 1;
+    }
+
+    if (count > 0) {
+        tips[count] = .init("meta", "use '--log-filter note' to silence this message");
+        log.logKVs(.note, .note, "config tips", tips[0 .. count + 1]);
+    }
+}

src/server/Server.zig

@@ -151,7 +151,7 @@ pub fn init(app: *App, address: sys_net.IpAddress) !*Server {
     const listener = try bindListener(app.config, &bound_address);
     errdefer _ = std.c.close(listener);
     pollfds[1] = .{ .fd = listener, .events = posix.POLL.IN, .revents = 0 };
-    log.note(.app, "server running", .{ .address = bound_address });
+    log.note(.note, "server running", .{ .address = bound_address });
 
     const port = bound_address.getPort();
     const json_version_response = try buildJSONVersionResponse(app, port);