I am trying to write a sample code to create an instance of a java class and then invoke a method using that instance. I am using node-java module to do this. The code compiles without any error. However when I hit the URL which actually hits the same code then I get the class not found exception.
I have verified that the jar and it is there in the same directory as index.js and the jar also contains the class file (Application.class) for which the instance is being created.
My index.js file
var java = require("java");
java.classpath.push("demo.jar");
var express = require('express');
var router = express.Router();
var Application = java.import('Application');
/* GET home page. */
router.get('/', function(req, res) {
var application = new Application();
var resp = application.getResponse();
res.render('index', { title: resp });
});
module.exports = router;
Sorry for my english. I had the same problem. Look [https://github.com/joeferner/node-java/issues/147]
my code:
`var java = require("java");
var path=require("path");
var fs=require("fs");
console.log("ruta in directory",path.join(__dirname));
console.log("exist file:",fs.existsSync(path.resolve(__dirname,"./lib-java/lib-tgd.jar")));
java.classpath.push("commons-lang3-3.1.jar");
java.classpath.push("commons-io.jar");
java.classpath.push(path.resolve(__dirname,"./lib-java/lib-tgd.jar"));
java.classpath.push(path.resolve(__dirname,"./lib-java/jackson-annotations- 2.5.1.jar"));
java.classpath.push(path.resolve(__dirname,"./lib-java/jackson-core-2.5.1.jar"));
java.classpath.push(path.resolve(__dirname,"./lib-java/jackson-databind-2.5.1.jar"));`
with path.resolve solves the problem of the file path
Related
I need to develop an API using NodeJS and also need to develop documentation for API also. I integrated with swagger auto-gen for swagger.json creation. But the swagger.json not generating properly if I used routes.js as below
var express = require('express');
module.exports = function(app) {
var userController = require('../controller/userController');
var apiRouter = express.Router();
var routerV1 = express.Router();
var routerV2 = express.Router();
app.use('/admin', apiRouter);
apiRouter.use("/v1", routerV1);
apiRouter.use("/v2", routerV2);
routerV1.route('/users').get(userController.getUsersV1);
routerV2.route('/users').get(userController.getUsersV2);
}
and also mapped these routes.js in swagger.js
Please suggest the best way to generate swagger.js
Do we need to create routes file for all controller?
Version 2 of swagger-autogen added this feature. Previous versions don't recognize routes. In your case, the best way to generate the file swagger.js is:
file: swagger.js
const swaggerAutogen = require('swagger-autogen')();
const outputFile = './swagger_output.json';
const endpointsFiles = ['./routes.js']; // root file where the route starts.
swaggerAutogen(outputFile, endpointsFiles).then(() => {
require('./index.js'); // Your project's root file
})
Update your module to the latest version.
And run your project with: node swagger.js
And about the routes file for all controller, you don't need to implement it for each one, but it also depends on the structure of your code. If you have a root route file like the example, this is enough for all sub-routes to be scanned. I hope it helps you. Take a look at this example if you need to:
swagger-autogen using router
I am trying to view the log File in the browser on hitting a particular url. I have the log file in my local (/logsFolder/app.log)
I tried the following codes:
Code: 1
var app = express();
var path = require('path');
var logFile = require('/logs/app');
app.use('/logs',logFile);
It threw error like
Error: Cannot find module '/logs/app'
Code :2
const app = express();
const path = require('path');
const router = express.Router();
router.get('/logFile', function(req, res){
console.log("inside logt :");
res.render('./logs/app.log');
});
can anyone Please help me to resolve.
Your log is static text file, not a javascript, nor json file, that why you can't require it. (code 1)
You are not using template engine either, that's why your code 2 didn't work, It cannot be render by itself.
You can use the built in express middleware for static files.
Try this:
app.use(express.static('logsFolder'))
Now you can access all the content of logsFolder by requesting the file name. For example: http://your-url/app.log
Or try your code 2 with res.sendFile instead of res.render
In express, I'm trying to move my minification to a requierd file:
app.js:
var app = express();
var minify = require("./minify.js");
In that file I try to set my template engine.
minify.js:
var app = express();
app.engine('html', mustacheExpress());
Later when I try to use to use the rendering engine in app.js, I get the error that no template-engine is set. It works if I run it all in the same file. I think the problem is that I declare the app-variable twice. How can I pass the app-variable into minify.js?
The problem is that you define new app variable, and you currently instantiate brand new express instance by calling express().
What you need to do is start using functions so that you can pass params (there are other methods too, but this is one that will work for you):
// app.js
var app = express();
var minify = require('./minify'); // don't include .js!
minify(app); // CALL the function that minify.js exports, passing params
// minify.js
module.exports = function(app) {
// because app comes as a parameter, it's the very same you've created in app.js
app.engine('html', mustacheExpress());
}
Again, there are many different methods and maybe proper approaches, depending on what you want to do, but this will do the job in your case. Read more about NodeJS and it's require system.
You can pass 'app' from app.js to your minify by using function in your module like Andrey said. You can do it like this too for example :
minify.js
module.exports = {
setAppEngine : function(app) {
app.engine( [...] );
}
}
And calling it like this in your app.js:
app.js
var app = express();
var minify = require("./minify.js").setAppEngine(app);
This solution is very useful because you can set and call others methods in minify.js. For example, you can do with the same code in minify.js:
app.js
var app = express();
var minify = require("./minify.js");
minify.setAppEngine(app);
I am calling a function from an external JS file in my routes file. So, I am trying to export a function from my externalFile.js file. However, when I run the node server, it throws Uncaught ReferenceError: exports is not defined . externalFile.js is in public/javascripts/ and the route files is in routes/.
External file (externalFile.js):
exports.capsolvingComplete = function (stdout){
//Received, display text and hide the spinner, put check in place.
$('#capsolv-complete').css("display", "block")
$('#capsolv-output').text(stdout);
}
Route file:
var express = require('express');
var router = express.Router();
var script = require('../public/javascripts/externalFile.js')
/* GET home page. */
router.get('/', function(req, res) {
res.render('index', { title: 'CapSolv' });
});
router.post('/file-upload', function(req, res){
script.capsolvingComplete("HI");
res.end("success");
})
module.exports = router;
Thank you for your help! Bit of a node noob here.
Looking at your example, mscdex is right. Anything you require in Node is designed to run on the server, and doesn't have access to the browser's DOM.
I would recommend building a REST API that accepts the file upload, stores it, and returns a JSON object containing metadata: i.e. where the file was stored, size, etc., and let your client deal with that.
I'd like to override the View class in the Express framework, used in Node.js. I want to augment the lookup method, but I can't see a way to do this without altering the Express and App modules. I'd favour deriving from the Express framework, but I can't figure out a neat way to do this.
Any ideas?
Thanks
It seems to me you should be able to:
var View = require('express/lib/view');
// Keep reference to original lookup method
var _lookup = View.prototype.lookup;
// Override lookup method
View.prototype.lookup = function (path) {
// Your implementation here
};
Update:
Run this as a demonstration:
var View = require('express/lib/view');
var _lookup = View.prototype.lookup;
var express = require('express');
View.prototype.lookup = function (path) {
console.log('LOOKUP!!! ' + path);
return _lookup.call(this, path);
};
var app = express();
app.get('/', function (req, res) {
res.render('foo.jade');
});
app.listen(3000);
Run
node app & sleep 1 && curl localhost:3000
I hope this will demonstrate the viability of this way of overriding a method.
It depends on which version of Express you are using.
You can easily augment the view lookup code only if your app is using Express prior to version 3
Since Express 3.0 that's not doable anymore.
You can check one of my old related answers for sample code:
Multiple View paths on Node.js + Express