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Building a Website with C++

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Re: Building a Website with C++

#41

Post by fuball63 »

ddorian43 wrote: post #35
fuball63 wrote: post #33

I'm in the early stages of a FaaS platform that uses CGI for the functions. As such, I have been collecting articles about general CGI development, and have them listed in my docs. If anyone is interested in writing large scale CGI apps (CGI is popping up a lot around here lately), these are some good resources: https://bigcgi.com/docs

Isn't cgi slow ? Don't you need something like fast-cgi (which lambda does I think) ?

CGI is slow because of the spin up time for individual processes for each request. FastCGI is fast because they run as one long running process that handles multiple requests.

While plain CGI is a slower, the advantage is that you don't have long running and potentially idle processes for low traffic periods, and process isolation is a little security boost.

I chose to have a slightly slower startup time, which hopefully remain constant in a load balanced cluster, to gain the advantages above.

Re: Building a Website with C++

#42

Post by pjmlp »

dahart wrote: post #37

> In this article, I’ll explain how you can use C++ to develop a website and some concrete reasons why you might consider doing so. I only saw one reason: performance. Did I miss some? Do people have other good use cases that justify paying the dev cost of using C++ for a web server? I'd guess with caching and a decent backend, it would be fairly hard to demonstrate a true need for performance that requires C++, but…

You missed IoT.

Preferably one would use some kind of network protocol with a native management console, but nowadays it is fashionable to have a mini webserver exposing a Web UI instead.

Re: Building a Website with C++

#43

Post by calebtroyer »

zebra_cross21 wrote: post #7

Just use rust man :| why do you want to bring all your security vulnerabilities and undefined behaviors to web?

Why do people think the C++ of today is the same as the C++ of 1998? Today we have concepts such as RAII to clean up our objects when they go out of scope. We have references which are essentially safe pointers to an extent (see dangling references). References have always existed, but people insist on using raw pointers still. Finally, for those use cases where heap allocated memory is absolutely necessary, we have smart pointers which clean up the memory they own when the smart pointer object goes out of scope (an application of RAII). Other unsafe practices carried over from C such as void * type erasure are being replaced with type-safe objects (see std::any for C++17, boost::any for pre-C++17).

Re: Building a Website with C++

#44

Post by bcjpjk »

nercury wrote: post #36
pleasecalllater wrote: post #27

Earlier quoted context omitted.

If you say that C++ is not memory safe you really don't know the modern C++. Of course you can use only `void *` everywhere... but you can also write your software in a totally different way. My C++ code has no pointers, just objects, which are automatically destroyed when I want to. The nice feature is that I know when the destructor is called, so the object will clear itself in a very nice way.

It's futile battle though to achieve both performance and safety in C++: as an example, safety requires avoiding moves, using reference counting, while achieving performance means avoiding copies and passing occasional references around, among other things. That's why advertising C++ solution as fast does not work well with "but C++ can be safe too!".

Moves can be safe, and copies can be dangerous.

C++ is a language that can be used like a sawed-off shotgun propped against a developer's foot, and with a hair trigger. Granted, it does not _have_ to be used this way, but it can be.

A good developer can be "safe by default" and can use profile-directed optimization to speed up areas that are performance critical. A great developer can build proofs that such performance improvements maintain safety guarantees. For the average developer, following modern C++ development practices creates code on par with other languages in terms of both safety and performance.

For most languages, a lot can be done in terms of optimization, profiling, and security. Even in higher-level languages, an FFI is available to rewrite critical portions of code in a lower level language for performance improvements. Careful attention to detail can provide critical performance improvements in any language without compromising on safety. Getting there requires model checking or formal methods, but that is also becoming more of a part of modern development practices.

Re: Building a Website with C++

#45

Post by flatline »

dahart wrote: post #37

> In this article, I’ll explain how you can use C++ to develop a website and some concrete reasons why you might consider doing so. I only saw one reason: performance. Did I miss some? Do people have other good use cases that justify paying the dev cost of using C++ for a web server? I'd guess with caching and a decent backend, it would be fairly hard to demonstrate a true need for performance that requires C++, but…

A large existing C++ code base is one good reason. It’s possible to write wrappers for most of the more web-friendly languages but they are a pain to debug and maintain for any complex API. So if you need a relatively lightweight web front-end for a complex C++ backend something like this may be a good choice. I still wouldn’t go the cgi route, or use makefiles for that matter.

Re: Building a Website with C++

#46

Post by utopcell »

Using CGI is silly and slow, for all but the simplest, stateless servers. If one wishes to avoid the overhead of learning a new framework, at least FastCGI should be considered. A relevant (but dated) discussion about web frameworks in C++ can be found in [1].

I am personally a big fan of CROW [2] and have used it many times in the past.

[1] https://softwareengineering.stackexchange.com/questions/5362... [2] https://github.com/ipkn/crow/blob/master/README.md

Re: Building a Website with C++

#47

Post by [deleted] »

pleasecalllater wrote: post #27
sddfd wrote: post #25

Bevor I'd use C++ I'd take a hard look at Go, figure out whether I really need C++ performance, or whether Go is just good enough. Go is rather performant and in contrast to C++ memory safe.

If you say that C++ is not memory safe you really don't know the modern C++. Of course you can use only `void *` everywhere... but you can also write your software in a totally different way. My C++ code has no pointers, just objects, which are automatically destroyed when I want to. The nice feature is that I know when the destructor is called, so the object will clear itself in a very nice way.

[deleted]

Re: Building a Website with C++

#48

Post by ecshafer »

dahart wrote: post #37

> In this article, I’ll explain how you can use C++ to develop a website and some concrete reasons why you might consider doing so. I only saw one reason: performance. Did I miss some? Do people have other good use cases that justify paying the dev cost of using C++ for a web server? I'd guess with caching and a decent backend, it would be fairly hard to demonstrate a true need for performance that requires C++, but…

I doubt the performance of a c++ web site would be better than c#/java or some other compiled languages for most non-trivial web sites. Once things like jits come into play, and you see large projects (1million+ loc) the performance advantage of c++ often disappears or it becomes less performant for things like web sites. Most companies do not have the time nor ability to do all those optimizations that theoretically exist that would make c++ more performant.

This isn't even counting the dev time difference

Re: Building a Website with C++

#49

Post by flatline »

chubot wrote: post #40

Really? Escaping, people! This code isn't practical or useful; it's dangerous and sloppy. cout \n"; ... cout \n"; FWIW I wrote an article about HTML escaping and shell here: http://www.oilshell.org/blog/2017/09/19.html Followup: http://www.oilshell.org/blog/2017/09/29.html Also if you want to use a native language for web sites (which I don't), Go is a better choice, as the standard library has html/template which pr…

CTemplate is a not-unreasonable option for C++ as well.

Re: Building a Website with C++

#50

Post by z92 »

I wrote my blog site in C. Runs as CGI and works just as fast as other tech stacks, say PHP.

C has very low startup time compare to say Java. And process fork-exec isn't as heavy weight under Linux as in Windows.

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