feat(attach): allow custom logger for attach neovim proc (#138)

* feat(attach): allow custom logger for attach neovim proc

* refactor(base): use typed logger interface

Author: kwonoj

Diff for: packages/neovim/src/api/Base.ts

@@ -1,12 +1,12 @@
 import { EventEmitter } from 'events';
 
 import { Transport } from '../utils/transport';
-import { logger as loggerModule } from '../utils/logger';
+import { Logger } from '../utils/logger';
 import { VimValue } from '../types/VimValue';
 
 export interface BaseConstructorOptions {
   transport?: Transport;
-  logger?: typeof loggerModule;
+  logger?: Logger;
   data?: Buffer;
   metadata?: any;
   client?: any;
@@ -31,7 +31,7 @@ export class BaseApi extends EventEmitter {
 
   protected prefix: string;
 
-  public logger: typeof loggerModule;
+  public logger: Logger;
 
   public data: Buffer | number;
 
@@ -49,7 +49,8 @@ export class BaseApi extends EventEmitter {
 
     this.setTransport(transport);
     this.data = data;
-    this.logger = logger || loggerModule;
+    // eslint-disable-next-line global-require
+    this.logger = logger || require('../utils/logger').logger;
     this.client = client;
 
     if (metadata) {

Diff for: packages/neovim/src/attach/attach.ts

@@ -2,20 +2,24 @@ import { createConnection } from 'net';
 import * as child from 'child_process';
 
 import { NeovimClient } from '../api/client';
-import { logger } from '../utils/logger';
+import { Logger } from '../utils/logger';
 
 export interface Attach {
   reader?: NodeJS.ReadableStream;
   writer?: NodeJS.WritableStream;
   proc?: NodeJS.Process | child.ChildProcess;
   socket?: string;
+  options?: {
+    logger?: Logger;
+  };
 }
 
 export function attach({
   reader: _reader,
   writer: _writer,
   proc,
   socket,
+  options = {},
 }: Attach) {
   let writer;
   let reader;
@@ -33,7 +37,9 @@ export function attach({
   }
 
   if (writer && reader) {
-    const neovim = new NeovimClient({ logger });
+    // eslint-disable-next-line global-require
+    const loggerInstance = options.logger || require('../utils/logger').logger; // lazy load to winston only if needed
+    const neovim = new NeovimClient({ logger: loggerInstance });
     neovim.attach({
       writer,
       reader,

Diff for: packages/neovim/src/utils/logger.ts

@@ -2,12 +2,12 @@ import * as winston from 'winston';
 
 const level = process.env.NVIM_NODE_LOG_LEVEL || 'debug';
 
-const logger = winston.createLogger({
+const winstonLogger = winston.createLogger({
   level,
 });
 
 if (process.env.NVIM_NODE_LOG_FILE) {
-  logger.add(
+  winstonLogger.add(
     new winston.transports.File({
       filename: process.env.NVIM_NODE_LOG_FILE,
       level,
@@ -16,11 +16,12 @@ if (process.env.NVIM_NODE_LOG_FILE) {
 }
 
 if (process.env.ALLOW_CONSOLE) {
-  logger.add(
+  winstonLogger.add(
     new winston.transports.Console({
       format: winston.format.simple(),
     })
   );
 }
 
-export { logger };
+export type Logger = Pick<winston.Logger, 'info' | 'warn' | 'error' | 'debug'>;
+export const logger: Logger = winstonLogger;