alepha/src/logger/__tests__/Logger.spec.ts

Easy-to-use modern TypeScript framework for building many kind of applications.

import { Alepha } from "alepha";
import { describe, it } from "vitest";
import {
  JsonFormatterProvider,
  LogDestinationProvider,
  LogFormatterProvider,
  MemoryDestinationProvider,
  PrettyFormatterProvider,
  RawFormatterProvider,
} from "../index.ts";
import { Logger } from "../services/Logger.ts";

/**
 * Exposes the protected `formatter` getter so the runtime format override
 * can be asserted by provider identity.
 */
class TestLogger extends Logger {
  public get activeFormatter() {
    return this.formatter;
  }
}

describe("Logger", () => {
  const createLogger = (service = "TestService", module = "test.module") => {
    const alepha = Alepha.create({
      env: { LOG_LEVEL: "info" },
    })
      .with({
        provide: LogDestinationProvider,
        use: MemoryDestinationProvider,
      })
      .with({
        provide: LogFormatterProvider,
        use: PrettyFormatterProvider,
      });

    return alepha.inject(Logger, {
      lifetime: "transient",
      args: [service, module],
    });
  };

  describe("parseLevel", () => {
    it("should return global level when no matching module found", ({
      expect,
    }) => {
      const logger = createLogger();
      // When no module-specific config matches, it falls back to global level
      expect(logger.parseLevel("debug", "non.matching.module")).toBe("DEBUG");
      expect(
        logger.parseLevel("specific.module:trace,warn", "non.matching.module"),
      ).toBe("WARN");
    });

    it("should parse simple global level", ({ expect }) => {
      const logger = createLogger();
      expect(logger.parseLevel("debug", "any.module")).toBe("DEBUG");
      expect(logger.parseLevel("trace", "any.module")).toBe("TRACE");
      expect(logger.parseLevel("warn", "any.module")).toBe("WARN");
      expect(logger.parseLevel("error", "any.module")).toBe("ERROR");
      expect(logger.parseLevel("silent", "any.module")).toBe("SILENT");
    });

    it("should parse module-specific level with colon separator", ({
      expect,
    }) => {
      const logger = createLogger();
      expect(logger.parseLevel("test:debug,info", "test.module")).toBe("DEBUG");
      expect(logger.parseLevel("alepha:trace,warn", "alepha.core")).toBe(
        "TRACE",
      );
      expect(logger.parseLevel("my.app:error,info", "my.app.service")).toBe(
        "ERROR",
      );
    });

    it("should parse module-specific level with equals separator", ({
      expect,
    }) => {
      const logger = createLogger();
      expect(logger.parseLevel("test=debug,info", "test.module")).toBe("DEBUG");
      expect(logger.parseLevel("alepha=TRACE,warn", "alepha.core")).toBe(
        "TRACE",
      );
      expect(logger.parseLevel("my.app=error,info", "my.app.service")).toBe(
        "ERROR",
      );
    });

    it("should handle multiple module configurations", ({ expect }) => {
      const logger = createLogger();
      const config = "alepha.core:trace,alepha.server:debug,my.app:error,info";

      expect(logger.parseLevel(config, "alepha.core")).toBe("TRACE");
      expect(logger.parseLevel(config, "alepha.server")).toBe("DEBUG");
      expect(logger.parseLevel(config, "my.app")).toBe("ERROR");
      expect(logger.parseLevel(config, "other.module")).toBe("INFO");
    });

    it("should handle semicolon separators", ({ expect }) => {
      const logger = createLogger();
      const config = "alepha:trace;my.app:error;info";

      expect(logger.parseLevel(config, "alepha.core")).toBe("TRACE");
      expect(logger.parseLevel(config, "my.app")).toBe("ERROR");
      expect(logger.parseLevel(config, "other.module")).toBe("INFO");
    });

    it("should use startsWith matching for modules", ({ expect }) => {
      const logger = createLogger();
      const config = "alepha:debug,info";

      expect(logger.parseLevel(config, "alepha")).toBe("DEBUG");
      expect(logger.parseLevel(config, "alepha.core")).toBe("DEBUG");
      expect(logger.parseLevel(config, "alepha.server.cache")).toBe("DEBUG");
      expect(logger.parseLevel(config, "other.alepha")).toBe("INFO");
    });

    it("should prioritize first matching module", ({ expect }) => {
      const logger = createLogger();
      const config = "alepha:debug,alepha.core:trace,info";

      // alepha.core matches both "alepha" and "alepha.core", but first match wins
      expect(logger.parseLevel(config, "alepha.core")).toBe("DEBUG");
    });

    it("should handle case insensitive levels", ({ expect }) => {
      const logger = createLogger();
      expect(logger.parseLevel("DEBUG", "any.module")).toBe("DEBUG");
      expect(logger.parseLevel("Test:TRACE,INFO", "test.module")).toBe("TRACE");
    });

    it("should handle whitespace around separators", ({ expect }) => {
      const logger = createLogger();
      const config = " alepha : debug , my.app : error , info ";

      expect(logger.parseLevel(config, "alepha.core")).toBe("DEBUG");
      expect(logger.parseLevel(config, "my.app")).toBe("ERROR");
      expect(logger.parseLevel(config, "other")).toBe("INFO");
    });

    it("should fall back to global level when no module match", ({
      expect,
    }) => {
      const logger = createLogger();
      const config = "specific.module:debug,trace";

      expect(logger.parseLevel(config, "other.module")).toBe("TRACE");
    });

    it("should handle empty parts gracefully", ({ expect }) => {
      const logger = createLogger();
      // Empty parts are now skipped gracefully
      expect(logger.parseLevel(",,debug,,", "any.module")).toBe("DEBUG");
      expect(logger.parseLevel("alepha:trace,,info", "alepha.core")).toBe(
        "TRACE",
      );
      expect(logger.parseLevel("alepha:trace,,", "other.module")).toBe("INFO");
      expect(logger.parseLevel("   ,  , debug ,  ", "any.module")).toBe(
        "DEBUG",
      );
    });

    it("should provide better error messages", ({ expect }) => {
      const logger = createLogger();
      expect(() =>
        logger.parseLevel("alepha:invalid,info", "alepha.core"),
      ).toThrow("Invalid log level 'invalid' for module pattern 'alepha'");
      expect(() => logger.parseLevel("badlevel", "any.module")).toThrow(
        'Invalid global log level "badlevel"',
      );
    });

    it("should support wildcard patterns", ({ expect }) => {
      const logger = createLogger();

      // Basic wildcard matching
      expect(logger.parseLevel("alepha.*:debug,info", "alepha.core")).toBe(
        "DEBUG",
      );
      expect(logger.parseLevel("alepha.*:debug,info", "alepha.server")).toBe(
        "DEBUG",
      );
      expect(logger.parseLevel("alepha.*:debug,info", "other.module")).toBe(
        "INFO",
      );

      // More specific patterns
      expect(
        logger.parseLevel("*.test:silent,*.core:trace,info", "alepha.test"),
      ).toBe("SILENT");
      expect(
        logger.parseLevel("*.test:silent,*.core:trace,info", "my.core"),
      ).toBe("TRACE");
      expect(
        logger.parseLevel("*.test:silent,*.core:trace,info", "other.module"),
      ).toBe("INFO");

      // Exact prefix match still works (existing behavior)
      expect(logger.parseLevel("alepha.core:debug,info", "alepha.core")).toBe(
        "DEBUG",
      );
      expect(
        logger.parseLevel("alepha.core:debug,info", "alepha.core.service"),
      ).toBe("DEBUG"); // startsWith behavior
    });

    it("should prioritize more specific wildcard matches", ({ expect }) => {
      const logger = createLogger();
      // First match wins, so order matters
      const config = "alepha.*:debug,alepha.core.*:trace,info";
      expect(logger.parseLevel(config, "alepha.core.service")).toBe("DEBUG"); // matches alepha.* first

      // Reverse order
      const config2 = "alepha.core.*:trace,alepha.*:debug,info";
      expect(logger.parseLevel(config2, "alepha.core.service")).toBe("TRACE"); // matches alepha.core.* first
    });
  });

  describe("asLogLevel", () => {
    it("should return valid log levels", ({ expect }) => {
      const logger = createLogger();
      expect(logger.asLogLevel("trace")).toBe("TRACE");
      expect(logger.asLogLevel("debug")).toBe("DEBUG");
      expect(logger.asLogLevel("info")).toBe("INFO");
      expect(logger.asLogLevel("warn")).toBe("WARN");
      expect(logger.asLogLevel("error")).toBe("ERROR");
      expect(logger.asLogLevel("silent")).toBe("SILENT");
    });

    it("should handle whitespace", ({ expect }) => {
      const logger = createLogger();
      expect(logger.asLogLevel(" debug ")).toBe("DEBUG");
      expect(logger.asLogLevel("  trace  ")).toBe("TRACE");
    });

    it("should throw error for invalid levels", ({ expect }) => {
      const logger = createLogger();
      expect(() => logger.asLogLevel("invalid")).toThrow(
        "Invalid log level: invalid",
      );
      expect(() => logger.asLogLevel("")).toThrow("Invalid log level: ");
      expect(() => logger.asLogLevel("DEBUqG")).toThrow(
        "Invalid log level: DEBUqG",
      );
    });
  });

  describe("level getter", () => {
    it("should update logLevel when state changes", ({ expect }) => {
      const alepha = Alepha.create({
        env: { LOG_LEVEL: "info" },
      })
        .with({
          provide: LogDestinationProvider,
          use: MemoryDestinationProvider,
        })
        .with({
          provide: LogFormatterProvider,
          use: PrettyFormatterProvider,
        });

      const logger = alepha.inject(Logger, {
        lifetime: "transient",
        args: ["TestService", "test.module"],
      });

      // Initial state
      expect(logger.level).toBe("INFO");

      // Change state
      alepha.store.set("alepha.logger.level", "debug");
      expect(logger.level).toBe("DEBUG");

      // Change to module-specific config
      alepha.store.set("alepha.logger.level", "test:trace,warn");
      expect(logger.level).toBe("TRACE");
    });

    it("should cache parsed level until state changes", ({ expect }) => {
      const alepha = Alepha.create({
        env: { LOG_LEVEL: "info" },
      })
        .with({
          provide: LogDestinationProvider,
          use: MemoryDestinationProvider,
        })
        .with({
          provide: LogFormatterProvider,
          use: PrettyFormatterProvider,
        });

      const logger = alepha.inject(Logger, {
        lifetime: "transient",
        args: ["TestService", "test.module"],
      });

      alepha.store.set("alepha.logger.level", "test:debug,info");
      const level1 = logger.level;
      const level2 = logger.level;

      expect(level1).toBe("DEBUG");
      expect(level2).toBe("DEBUG");
      expect(level1).toBe(level2); // Should be same instance/value
    });
  });

  describe("format getter", () => {
    const make = () => {
      const alepha = Alepha.create({ env: { LOG_LEVEL: "info" } })
        .with({
          provide: LogDestinationProvider,
          use: MemoryDestinationProvider,
        })
        .with({
          provide: LogFormatterProvider,
          use: PrettyFormatterProvider,
        });
      const logger = alepha.inject(TestLogger, {
        lifetime: "transient",
        args: ["TestService", "test.module"],
      });
      return { alepha, logger };
    };

    it("falls back to the register-time formatter when unset", ({ expect }) => {
      const { logger } = make();
      expect(logger.activeFormatter).toBeInstanceOf(PrettyFormatterProvider);
    });

    it("honors the alepha.logger.format state override (read live)", ({
      expect,
    }) => {
      const { alepha, logger } = make();

      alepha.store.set("alepha.logger.format", "json");
      expect(logger.activeFormatter).toBeInstanceOf(JsonFormatterProvider);

      alepha.store.set("alepha.logger.format", "raw");
      expect(logger.activeFormatter).toBeInstanceOf(RawFormatterProvider);

      alepha.store.set("alepha.logger.format", "pretty");
      expect(logger.activeFormatter).toBeInstanceOf(PrettyFormatterProvider);

      // Unknown / cleared → back to the register-time default.
      alepha.store.set("alepha.logger.format", undefined);
      expect(logger.activeFormatter).toBeInstanceOf(PrettyFormatterProvider);
    });
  });

  describe("isLevelEnabled", () => {
    const at = (level: string) => {
      const alepha = Alepha.create().with({
        provide: LogDestinationProvider,
        use: MemoryDestinationProvider,
      });
      const logger = alepha.inject(Logger, {
        lifetime: "transient",
        args: ["TestService", "test.module"],
      });
      // Set after inject: the logger module's register defaults the level to
      // "trace" in test mode, so a pre-inject set would be overwritten.
      alepha.store.set("alepha.logger.level", level);
      return { alepha, logger };
    };

    it("enables a level only when it is at or above the active level", ({
      expect,
    }) => {
      const { logger } = at("info");
      expect(logger.isLevelEnabled("ERROR")).toBe(true);
      expect(logger.isLevelEnabled("WARN")).toBe(true);
      expect(logger.isLevelEnabled("INFO")).toBe(true);
      expect(logger.isLevelEnabled("DEBUG")).toBe(false);
      expect(logger.isLevelEnabled("TRACE")).toBe(false);
    });

    it("enables DEBUG once the active level is debug, but not TRACE", ({
      expect,
    }) => {
      const { logger } = at("debug");
      expect(logger.isLevelEnabled("DEBUG")).toBe(true);
      expect(logger.isLevelEnabled("INFO")).toBe(true);
      expect(logger.isLevelEnabled("TRACE")).toBe(false);
    });

    it("enables everything at trace and reacts to live state changes", ({
      expect,
    }) => {
      const { alepha, logger } = at("trace");
      expect(logger.isLevelEnabled("TRACE")).toBe(true);
      expect(logger.isLevelEnabled("DEBUG")).toBe(true);

      alepha.store.set("alepha.logger.level", "warn");
      expect(logger.isLevelEnabled("DEBUG")).toBe(false);
      expect(logger.isLevelEnabled("WARN")).toBe(true);
    });
  });
});