Make root logger global so it's shared amongst versions

src/index.js

@@ -9,8 +9,7 @@ const pino = require('pino');
  * Variables
  */
 
-let rootLogger;
-const loggersSymbol = Symbol('debino.loggers');
+const globalSymbol = Symbol.for('debino');
 
 /**
  * Create child logger bindings based on a given `namespace`, `prefix` and `suffix`.
@@ -39,20 +38,19 @@ const setRootLogger = logger => {
     throw new Error('The logger instance must not have a name binding configured');
   }
 
-  // Ensure loggers cache map is set on the root logger.
-  if (!logger[loggersSymbol]) {
-    logger[loggersSymbol] = new Map();
+  if (global[globalSymbol].loggers.size > 0) {
+    throw new Error('The root logger must be set before creating any child logger');
   }
 
-  rootLogger = logger;
+  global[globalSymbol].rootLogger = logger;
 };
 
 /**
  * Create a logger based on a given `namespace` and `options`.
  */
 
 const debino = (namespace, { prefix = 'sub', suffix = 'component', ...options } = {}) => {
-  const loggers = rootLogger[loggersSymbol];
+  const { loggers, rootLogger } = global[globalSymbol];
   let childLogger = loggers.get(namespace);
 
   // Create the logger for this namespace if it doesn't exist.
@@ -74,10 +72,13 @@ const debino = (namespace, { prefix = 'sub', suffix = 'component', ...options }
 };
 
 /**
- * Configure the default root logger.
+ * Configure the default root logger and initialize loggers cache.
  */
 
-setRootLogger(pino());
+global[globalSymbol] = {
+  loggers: new Map(),
+  rootLogger: pino()
+};
 
 /**
  * Exports.

src/index.test.js

@@ -10,6 +10,10 @@ import debug from 'debug';
  * Tests for `debino()`.
  */
 
+beforeEach(() => {
+  global[Symbol.for('debino')].loggers.clear();
+});
+
 describe('debino', () => {
   beforeEach(() => {
     delete process.env.LOG_LEVEL;
@@ -102,6 +106,12 @@ describe('setRootLogger', () => {
     );
   });
 
+  it('should throw an error if called after a child logger has been created', () => {
+    debino('foo');
+
+    expect(() => setRootLogger(pino())).toThrow('The root logger must be set before creating any child logger');
+  });
+
   it('should store the logger as the root one', () => {
     const rootLogger = pino({ base: { foo: 'bar' } });
 
@@ -115,18 +125,4 @@ describe('setRootLogger', () => {
     expect(logger.bindings().name).toBe('foo');
     expect(logger.bindings().foo).toBe('bar');
   });
-
-  it('should not overwrite loggers cache if already set', () => {
-    const rootLogger = pino();
-
-    setRootLogger(rootLogger);
-
-    const child1 = debino('foo');
-
-    setRootLogger(rootLogger);
-
-    const child2 = debino('foo');
-
-    expect(child1).toBe(child2);
-  });
 });