When using npm, pip, and friends, I faced many problems in the past: Very often compressed, minified, combined JS files with totally insufficient information about their authors and respective licenses.
Or convenience copies of other programs or parts of other programs with minor or not-so-minor changes without clear indication, what this software was and by whom, and what the changes were and by whom.
Dear node. Update : This was a rage post, and not really saying anything substantial, but I want to quote here the first comment reply from Christian as I think it is much more interesting: I see a recurring pattern here: developers create something that they think is going to simplify distributing things by quite a bit, because what other people have been doing is way too complicated[tm].
In the initial iteration it usually turns out to have three significant problems: a nightmare from a security perspective there's no concern for stability, because the people working on it are devs and not people who have certain reliability requirements bundling other software is often considered a good idea, because it makes life so much easier[tm] Given a couple of years they start to catch up where the rest of the world e.
I've seen this pattern over and over again: the Ruby ecosystem was a catastrophe for quite some time just ask e. And I also want to quote myself with what I think are some things you could do to improve this situation: You want to make sure your build is reproducible in the most basic sense of being re-buildable from scratch , that you are not building upon scraps of code that nobody knows where they came from, or which version they are.
If possible, at the package level don't vendor dependencies, depend on the user having the other dependencies pre-installed. Building should be a mainly automatic task. Automation tools then can take care of that cpan, pip, npm. With other programming languages, we are accustomed to the predictable order of execution where two statements will execute one after another, unless there is a specific instruction to jump between statements.
Even then, these are often limited to conditional statements, loop statements, and function invocations. However, in JavaScript, with callbacks a particular function may not run well until the task it is waiting on is finished. The execution of the current function will run until the end without any stop:. However, what if we want to export this function directly, and not as the property of some object?
We can overwrite exports to do this, but we must not treat it as a global variable then:. JavaScript has the notion of exceptions. However, try-catch will not behave as you might expect it to in asynchronous situations. This is how errors are handled in a different way in Node. Numbers in JavaScript are floating points - there is no integer data type. That is exactly when mistakes related to this happen.
Since floating point numbers can only hold integer representations up to a certain value, exceeding that value in any calculation will immediately start messing it up. As strange as it may seem, the following evaluates to true in Node. Even though Numbers are floating points, operators that work on integer data types work here as well:. Trying to do a bitwise-or of 1 with that same large number will evaluate to 1.
You may rarely need to deal with large numbers, but if you do, there are plenty of big integer libraries that implement the important mathematical operations on large precision numbers, such as node-bigint.
As an example, we shall build a small web server that serves Gravatar images:. In this particular example of a Node. However, imagine if the size of the contents we are proxying were thousands of megabytes in size. A much better approach would have been this:. Here, we fetch the image and simply pipe the response to the client.
At no point do we need to read the entire content into a buffer before serving it. Pass an object to it and it will print it as a JavaScript object literal. It accepts any arbitrary number of arguments and prints them all neatly space-separated. Instead, use one of the amazing libraries that are built just for this, such as debug.
Woe betide you if you happen to forget to catch an exception. Your absolutely critical Node. This for me is fairly unforgiveable for a language that you may want to build mission-critical apps with. I once had a very subtle issue where I was seeing an undefined:undefined error message in the console after running some tests. No stack trace, just the above error message. My first thoughts. What the hell? Since when could you get an undefined:undefined rather than an error message and stack trace.
It actually turned out that the error object was actually a string because someone had written So what they'd intended was to add additional text to an error thrown further up the call stack so becoming This wasn't initially spotted because there was a disconnect between two modules a common one and one that consumed the common module. Obviously this is a clear problem with the fact that there's no static type checking in Javascript and it's not a compiled language.
Again, as Java developers we're pretty spoiled here. There's also Gradle as well which again is really really great. NPM on the other-hand is a terrible dependency management tool. It's great when it works but when it doesn't you often get incomprehensible errors and stack traces. I've found that because of a distinct lack of a decent debugging toolset for the Node. I actually can't remember the last time I had to log out stuff in Java because the debugging tools are just so darn good.
In the Node. Looking at API documentation for modules is therefore a must. A good article about the event loop in Node. I have one real-world example where I have used Node. This website is for selling one item using PayPal and the client also wanted to have a counter which shows the amount of sold items. Client expected to have huge amount of visitors to this website. I decided to make the counter using Node. The Node. Get the sold items amount from a Redis database, increase the counter when item is sold and serve the counter value to users via the API.
There is nothing like Silver Bullet. Everything comes with some cost associated with it. It is like if you eat oily food, you will compromise your health and healthy food does not come with spices like oily food. It is individual choice whether they want health or spices as in their food.
Same way Node. If your app does not fit into that scenario you should not consider it for your app development. I am just putting my thought on the same:. There are other option to use in place of Node. JS however Vert. Another great thing that I think no one has mentioned about Node.
My piece: nodejs is great for making real time systems like analytics, chat-apps, apis, ad servers, etc. Hell, I made my first chat app using nodejs and socket. Its been several years since I have started using nodejs and I have used it in making many different things including static file servers, simple analytics, chat apps and much more.
This is my take on when to use nodejs. Its a very versatile webserver so you can use it wherever you want but probably not these places. Keep in mind that I am just nitpicking. For static file servers, apache is better mainly because it is widely available.
The nodejs community has grown larger and more mature over the years and it is safe to say nodejs can be used just about everywhere if you have your own choice of hosting.
On Mobile front, prime-time companies have relied on Node. Check out why? LinkedIn is a prominent user. Their entire mobile stack is built on Node. They went from running 15 servers with 15 instances on each physical machine, to just 4 instances — that can handle double the traffic! They were able to tune a regular developer-quality Ubuntu workstation to handle more than , active connections per node.
Walmart re-engineered its mobile app to use Node. Node best for concurrent request handling -. From last 2 years I am working on JavaScript and developing web front end and I am enjoying it. But in real it is not that easy, If data we are getting is not correct or there is some server error then we stuck and we have to contact our back end guys over the mail or chat sometimes on whatsApp too :.
This is not cool. Guess what! Do you have any other reason to use node for rest API? Suppose two concurrent request occurs r1 and r2 , each of them require database operation. So In traditional system what will happens :. Waiting Way : Our server starts serving r1 request and waits for query response.
Threading Way : Our server will creates two threads for both requests r1 and r2 and serve their purpose after querying database so cool its fast. But it is memory consuming because you can see we started two threads also problem increases when both request is querying same data then you have to deal with deadlock kind of issues.
So its better than waiting way but still issues are there. Nodeway : When same concurrent request comes in node then it will register an event with its callback and move ahead it will not wait for query response for a particular request. Whenever any query finishes it triggers its corresponding event and execute its callback to completion without being interrupted.
I have used Cloud9 IDE for a while and now I can't imagine without it, it covers all the development lifecycles. All you need is a browser and you can code anytime anywhere on any devices. You don't need to check in code in one Computer like at home , then checkout in another computer like at work place.
One more thing node provides is the ability to create multiple v8 instanes of node using node's child process childProcess. So offloading a background job that requires huge server load becomes a child's play and we can easily kill them as and when needed. I've been using node a lot and in most of the apps we build, require server connections at the same time thus a heavy network traffic. Frameworks like Express.
It isn't really a Node. Because I didn't really think it would be appropriate to fail to give readers a webserver, Node. The case was closed before it was even opened. I could have given a very rosy view of my experience with Node. Instead I was honest about good points and bad points I encountered.
Warning: Node. With Node. This problem affords new users with great opportunity to feel stupid because they thought they had fixed the problem, but the old, buggy behavior is completely unchanged. And it is easy to forget to bounce the server; I have done so multiple times. The Appendix, which I did not really want after the rising crescendo in the last chapters and the conclusion, talks about what I was able to find in the ecosystem, and provided a workaround for moronic literalism:.
Another database that seemed like a perfect fit, and may yet be redeemable, is a server-side implementation of the HTML5 key-value store. This approach has the cardinal advantage of an API that most good front-end developers understand well enough.
But with the node-localstorage package, while dictionary-syntax access is not offered you want to use localStorage. Do server-side JavaScript developers need to be protected from themselves? For client-side database capabilities, a 5MB quota per website is really a generous and useful amount of breathing room to let developers work with it.
You could set a much lower quota and still offer developers an immeasurable improvement over limping along with cookie management. But on the other hand, 5MB is not a particularly large portion of most disks purchased any time recently, meaning that if you and a website disagree about what is reasonable use of disk space, or some site is simply hoggish, it does not really cost you much and you are in no danger of a swamped hard drive unless your hard drive was already too full.
Most developers will neither need nor want tools acting as a nanny and protecting them from storing more than 5MB of server-side data. And the 5MB quota that is a golden balancing act on the client-side is rather a bit silly on a Node.
That could get painful if you go viral! The documentation states that the quota is customizable, but an email a week ago to the developer asking how to change the quota is unanswered, as was the StackOverflow question asking the same.
The only answer I have been able to find is in the Github CoffeeScript source, where it is listed as an optional second integer argument to a constructor.
The best thing to do with this misfeature is probably to specify that the quota is Infinity:. Here are the good parts. Just forget that anything else is there. Here are the areas to avoid at almost any cost. Here are the areas with some of the richest paydirt to be found in ANY language or environment.
And given the degree of enthusiasm and sheer work-hours on all projects, it may be warranted in a year, or two, or three, to sharply temper any remarks about an immature ecosystem made at the time of this writing. If your application mainly tethers web apis, or other io channels, give or take a user interface, node.
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