CppCMS Blog :: Progress

Web Server Upgrade

http://cppcms.com and http://blog.cppcms.com were migrated to new ec2 Ubuntu 20.04 server. If you notice any issues update please.

Known Issues: there are problems with wikipp table of content. I'll handle it later. Fixed

Next CppCMS Major Feature Poll

I'm looking into implementing next major feature that I can complete with reasonable effort. I have a list of following topics:

HTTP/1.1 support - it would allow keep alive support and better performance overall for multiple requests. It would allow future implementation of web sockets.
Multiple-Event-Loop support - today there is only 1 event loop for the service and it can be a bottleneck for small requests on systems with high core count.
SSL support - for embedded systems that need proper web server.
C++11 cleanup - replace all booster primitives that exist in C++11 with standard (shared_ptr, thread, mutex, etc) provide move constructors for many objects, replace auto_ptr by unique_ptr.

Feel free to suggest other ideas that you can think of that would be beneficial.

Comment below or sent e-mail to cppcms-users mailing list.

CppCMS 1.2.1 - security update was released today

Security Bug Fixes:

Fixed security bug fix in JSON parser module that can lead to DOS

Bugs Fixed:

Fixed issues #36 - building with GZIP disabled
Fixed issue #150 - incorrect parsing of multipart form

Changes:

By default CppCMS now uses OpenSSL instead of GNU-TLS if both available (you can change behavior back by adding -DDISABLE_OPENSSL=ON to cmake)

Special Thanks to Khaled Yakdan from code-intelligence.de for reporting this security issue

CppCMS 1.1.1 Release Candidate 1 is Available

New version includes following changes:

Nightly build system updated to moderns OSes/compilers:
1. Windows XP -> Windows 7
2. MSVC 2008 x86 to MSVC 2017 x86/x65
3. MinGW GCC 4.5 x86 -> 7.1 x86/x64
4. OpenSolars 2009 to Solaris 11
5. FreeBSD 10 -> FreeBSD 11.1
6. Added travis.yml for Mac OS X builds
Improved http timeouts handling on non Linux/Windows OSes.
Fixed incorrect asynchronous IO handing in *cgi API.
Added support of SOL_SNDBUF/SOL_RCVBUF to service configuration
Fixed HTTP timeout handling on Solaris
Fixed #24 failure to send large blocks asynchronously over FastCGI
Fixied issue #21 Program produces 100% CPU load on one core - due to incorrect EOF handling
Fixed icu backend test for ICU >= 60.1
Fixed missing getenv(std::string const &) issue #16
Fixed issues with codecvt generation FreeBSD/clang
Use Windows Vista/7 API by defaults since XP reached EOL.
Fixed incorrect async connect error handling
Lineup with Boost.Locale 1.65
Updated session interface for external languages and unit tests

CppCMS 1.1.0 Beta was released

After the goals for 1.2 were completed I announce official CppCMS 1.1.0 beta (stable will be 1.2.0)

It is available on the usual place:

https://sourceforge.net/projects/cppcms/files/cppcms/1.1.0-beta/cppcms-1.1.0.tar.bz2

It includes many new and important features:

http://cppcms.com/wikipp/en/page/cppcms_1_2_whats_new

Now I ask the community to fully participate in beta testing so 1.2 will be released ASAP.

Goals for beta testing

Framework Unit Test:

Download the beta version, build, run tests
Report on what platform you tested: OS, Compiler version, standard library (libstdc++/libc++)
Have you had any tests failed and if you had please attach Testing/Temporary/LastTest.log and CMakeCache.txt from your build directory

I specially need tests on Mac OS X various versions, various ARM platforms like raspberry pi and Windows different compilers

Compatibility Test:

Try to build your existing applications with latest version, report any problems
If you have been using CppCMS 1.0.5 till now please try to build CppCMS 1.1.0 and run existing programs with new shared objects/dll WITHOUT rebuilding your applications - it must work as is!

Feature Test:

Go to: http://cppcms.com/wikipp/en/page/cppcms_1_2_whats_new

And try some of new features, report any issues with them or any problems with API design.

If all goes smoothly I'll release 1.2.0 - official stable version.

CppCMS code migrated to GitHub

After multiple requests and my final decision the CppCMS web framework code migrated to GitHub

https://github.com/artyom-beilis/cppcms

Please note:

Only CppCMS framework migrated, other subprojects like CppDB or Wikipp are still pending conversion
The main bug tracker is still on source-forge - however I'll relate to issues opened on GitHub

Session Sharing with Non-CppCMS technologies

One of the problems in integrating different technologies on same web site is sharing the data between them, in particular sharing session data.

For example you have a huge web platform written in PHP or Java and you want to improve performance of certain subsystems poring them to CppCMS. On of the first issues you'd encounter is how to share the session between them - so every side would know who is the user, what permissions he has, etc.

So I made cppcms::session_pool and cppcms::session_interface accessible outside the usual request/response scope and wrapped it with pure C API - such that no C++ exceptions are thrown and every function is resolvable via dlopen/GetProcAddress- to make it more accessible for integration with different languages.

Several modules for different programming languages were implemented allowing smooth integration with their web frameworks and APIs:

PHP - using Swig
Java/Servlet - using JNA
Python/Django - using ctypes (but not limited to Django)
Asp.Net - using PInvoke

Actually there is no particular limits regarding technology - just a question of implementing loadable module for a specific language/platform.

In general it consists of a SessionPool object that is created from a configuration file and exists globally. It generates a special Session objects that is loaded from Http Request cookies, updated and saved to the Http Response object.

It looks like this:

PHP:

// pool initialization
$pool=CppCMS_SessionPool::from_config('cppcms-config.js');
// per request session access
$session=$pool->session();
$session->load();
$x=0;
if($session->is_set('x')) {
        $x=$session['x'];
}

$x=intval($x)+1;
$session['x']=$x;
$session->save();
...

Java/Servlet:

static SessionPool pool;

public void init() throws ServletException
{
    pool = SessionPool.openFromConfig("/path/to/cppcms-config.js");
}

public void doGet(HttpServletRequest request,
                  HttpServletResponse response) 
                    throws ServletException, IOException
{
    Session session = pool.getSession();
    session.load(request);
    String x="0";
    if(session.isSet("x"))
        x=session.get("x");
    x=Integer.toString(Integer.parseInt(x)+1);
    session.set("x",x);
    session.save(response);
    session.close();
    ...
}

Python with Django:

# Create global pool
pool=cppcms.SessionPool('/path/to/cppcms-config.js')

# Actual view
def home(request):
    s=pool.session()
    s.load(django_request=request)
    v='0'
    if 'x' in s:
            v= s['x']
    s['x']=str(int(v)+1)
    response = HttpResponse()
    s.save(django_response=response)
    ...

C#/ASP.Net:

static SessionPool pool;
static Example() {
    pool = SessionPool.FromConfig("cppcms-config.js");
}
protected void Page_Load(object sender,EventArgs e)
{
    using(Session s = pool.Session()) {
        s.Load(Request);
        string v="0";
        if(s.IsSet("x"))
            v=s["x"];
        v = (int.Parse(v) + 1).ToString();
        s["x"]=v;
        s.Save(Response);
    }
    ...
}

So basically you have a full access to CppCMS session from 3rd party most popular technologies.

Still thinking of implementing a module for Ruby on Rails but I have never written a line of code in Ruby so it is quite challenging for me. I'll probably wait till somebody contributes one.

Serving All Israeli News Web Sites from a Single EC2 instance...

For the last year the development of the CppCMS project was less active. The vast majority of the work hours were spent on a customer's project that used CppCMS to create an outstanding advertisement system.

The project is called Linicom.

Today, when Linicom is up, running and maintained by a larger team, so I can resume the activity on the core CppCMS project itself.

Few words about Linicom:

Linicom is an engine that provides content and visitor sensitive advertisements for almost all large Israeli news web sites: including Ynet, Haaretz, Jerusalem Post, Mako, Walla and other significant web sites in Israel and abroad.

Here some interesting facts:

Linicom is based on CppCMS technology.
The system serves around 10,000,000 custom requests a day, i.e ~115 req./s.
During peak hours, it servers around 160 requests per second.
Its typical network output is around 11 megabit per second.
Its total memory consumption (web server, database, applications, OS) is only around 350Mb.
The server's average CPU load is around 5%
The server runs on a c1.medium Amazon EC2 instance.

The system runs behind Lighttpd and uses PostgreSQL for persistent data storage. Also PostgreSQL is used extensively, all real time data is stored in memory.

Almost every request needs data processing in order to provide highly customized advertisements. In technical terms it means that almost no request can be "outsourced" to a static files - every request for every customer should be processed explicitly.

This system is probably one of the classic applications of CppCMS technology - web based system that required to be fast and efficient, being able to handle outstanding and sometimes unexpectedly changing loads without problems and provide high QoS.

Use of in-memory data storage, caching and efficient handing of the data that can't be cached is were CppCMS shines. Having a big growth potential with a minimal required maintenance and high reliability allows the to handle the business-end safely without worrying about performance issues.

CppCMS 1.0.5 Released

Bug Fixes:

Fixed 121, 98 - bug caused invalid year formatting/parsing by icu backend - fixed incorrect use of year of the week instead year
Fixed 122 - memory leak in Win32 threading library
Fixed 105 - string_key.h has a bad operator '!='
Fixed 119 - bad html formatting.
Fixed 106 - IPv6 support on Winows
Fixed 129 - cppcms_make_key - invalid option name
Fixed 97 - impossible to use upper case in namespace in <% include %>
Fixed 84 - 64K fd limit
Fixed 108 - test_locale_boundary & booster_locale_formatting failure
Fixed various issues libc++/clang support
Significantly improved multipart parsing closing f.r. 27
Removed reuse_address socket option use at Windows

Minor Security Improvements:

Issue 117: possibility of Timing Attack Vulnerability

Platform Support:

NetBSD is supported platform
FreeBSD added support of POSIX locale & clang/libc++

The code is downloadable from sourceforge. Binary RPM releases already available at The Open Build Service repository. Debian packages would be published soon.

Update: Debian and Ubuntu packages are ready at the repository.

CppCMS 1.0.4 Released

This is a critical bug fix release that relates to session handing in Internet Explorer.

Added "Expires" to cookie expiration time handling that is supported by IE.

Prior to this release, cppcms session cookies used max-age option, that IE does not recognize. Starting from this release the session cookies would have both Expires and Max-Age options. All browsers that use Max-Age would ignore Expires if both given.

New options that control the session cookie properties are added, see expiration_method that would allow to alter the behavior and handle possible clock skew issues

Special thanks to Saikumar Gandapodi who reported me this issue.