npm install gulp-mailparser    
> gulp-mailparser plugin for mailparser
First, install gulp-mailparser as a development dependency:
``shell`
npm install --save-dev gulp-mailparser
Then, add it to your gulpfile.js:
`javascript
var mailParser = require("gulp-mailparser");
gulp.task("mailparser",function(){
return gulp.src("./src/*.eml",{ buffer: false }) // streams need
.pipe(mailParser())
.pipe(gulp.dest("./dist"))
});
``