cppcms-users — Disussions of users of CppCMS

[Cppcms-users] Question on even handling

[Shiv S. D. <shi...@gm...>]

Hi,

Say I am running cppcms with 8 worker process and worker threads set
to 1. Now let us say multiple uploads are coming which are large. Do I
need to handle that in CppCMS worker processes specifically or IO is
asynchronous in worker process sockets by default? Because if sockets
are read by worker processes then for large uploads only 8 concurrent
transfers would be possible in such configuration.

-- 
Respect,
Shiv Shankar Dayal

Re: [Cppcms-users] websockets

[Artyom B. <art...@gm...>]

On Thu, Mar 24, 2016 at 3:53 PM, Shiv Shankar Dayal
<shi...@gm...> wrote:
> Hi,
>
> As far as I know CppCMS has planned wesockets for one of the future
> releases. One of the best available libraries is
> https://libwebsockets.org/index.html.

Yes indeed it is planned for 1.4 with other HTTP server improvements

http://cppcms.com/wikipp/en/page/cppcms_1x_tasks#HTTP.Server.improvements

> Can we not simply integrate it
> and provide a nice OO wrapper in CppCMS?
>

Probably you can on and **independent port** using CppCMS event loop
but you would have problems with rest of the stuff
that CppCMS provides for connections - you'll need to handle stuff
like sessions manually

Also I assume it would be simpler to implement WS support directly
(finally it isn't that complicated protocol)

HOWEVER

I'd strongly discourage you from using WebSockets UNLESS you need real
time BI-directional communication like a
game where you need to send mouse movements or rapid key strokes to
server in real time.


(A) It isn't HTTP and vast majority of proxies do not forward it
properly, so to make it work in real world you must use HTTPS. For
example non-https web sockets do not work on mobile platforms that use
proxy frequently.
(B) it does not have proper Web Server interface i.e. you can't use it
over FastCGI or SCGI you must run behind reverse HTTP proxy that
handles web sockets as well.

Frequently WebSockets used for Push only technology - for such a case
I recommend to use Server Sent Events

(a) it is true HTTP
(b) it provides self synchronization features
(c) it is much simpler to use and implement
(d) it provides trivial to implement fallback (for both client and
server) to long-polling in case older browser.


> --
> Respect,
> Shiv Shankar Dayal
>

Regards,

Artyom Beilis

[Cppcms-users] websockets

[Shiv S. D. <shi...@gm...>]

Hi,

As far as I know CppCMS has planned wesockets for one of the future
releases. One of the best available libraries is
https://libwebsockets.org/index.html. Can we not simply integrate it
and provide a nice OO wrapper in CppCMS?

-- 
Respect,
Shiv Shankar Dayal

Re: [Cppcms-users] read file and download it

[Marcel H. <ke...@co...>]

On 03/23/2016 12:22 PM, mawan sugiyanto wrote:
> the restriction is about file name restriction. and don't about download
> mechanism?
> for example if i create pdf file on the fly, and read it, and then put
> on output response, is it no problem?
> 
? I don't get the problem. If you create a PDF
a) with an external application (e.g. latex, pdfcreator, etc.) you could
ether do the trick with the x-sendfile (let your webserver do the job)
b) create the pdf-file in memory (e.g. with a c++ library), then you can
stream the pdf straight out with `response().out() << f.rdbuf();`

You don't have to read it in memory, so there should be no problem

Re: [Cppcms-users] Expected date of next release

[Artyom B. <art...@gm...>]

Great Question!

In general CppCMS 1.1 beta is almost ready (than 1.2 is just matter of
user feedback)

If you look at the roadmap:

http://cppcms.com/wikipp/en/page/cppcms_1x_tasks

I have few major things:

1. Complete plugin testing suite - and its combination with templates
and localization
2. Write down an example of a new plugin API to make sure I didn't miss a thing
3. Write a test suite for external session API (and do some updates)
4. Virtual host support (matter of few hours)

To do all this I need about 3-4 quiet work days...
I hope I'll be able to be ready before May 1st if nothing goes wrong.

Additionally currently my nightly tests system is down due to HW
malfunction which also
somewhat creates a bottle neck as there are some stuff to fix and test

http://cppcms.com/files/nightly-build-report.html

So I need to buy a new computer to replace my 10 years old PC that
runs the tests.

Bottom line I hope I'll have some available time soon (during upcoming holidays)
but I can't guarantee.

In any case current trunk is very stable and besides very new plugin
API and external
sessions API I don't see any issues to work with it directly.

Regards

Artyom Beilis


On Wed, Mar 23, 2016 at 1:30 PM, Shiv Shankar Dayal
<shi...@gm...> wrote:
> It has been quite sometime since last release. Is there any expected
> date of next release? I know that you are busy Artyom. :)
>
> --
> Respect,
> Shiv Shankar Dayal
>
> ------------------------------------------------------------------------------
> Transform Data into Opportunity.
> Accelerate data analysis in your applications with
> Intel Data Analytics Acceleration Library.
> Click to learn more.
> http://pubads.g.doubleclick.net/gampad/clk?id=278785351&iu=/4140
> _______________________________________________
> Cppcms-users mailing list
> Cpp...@li...
> https://lists.sourceforge.net/lists/listinfo/cppcms-users

[Cppcms-users] Expected date of next release

[Shiv S. D. <shi...@gm...>]

It has been quite sometime since last release. Is there any expected
date of next release? I know that you are busy Artyom. :)

-- 
Respect,
Shiv Shankar Dayal

Re: [Cppcms-users] read file and download it

[mawan s. <ma...@gm...>]

Dear Marcel

the restriction is about file name restriction. and don't about download
mechanism?
for example if i create pdf file on the fly, and read it, and then put on
output response, is it no problem?

Thankyou

On Wed, Mar 23, 2016 at 6:16 PM, mawan sugiyanto <ma...@gm...> wrote:

> Thankyou Marcel.
>
>
>
> On Wed, Mar 23, 2016 at 6:07 AM, Marcel Hellwig <ke...@co...>
> wrote:
>
>> just don't
>>
>> http://cppcms.com/wikipp/en/page/cppcms_1x_serving_static_files
>>
>> On 03/21/2016 07:56 AM, mawan sugiyanto wrote:
>> > Dear All
>> >
>> > how to read file and put on response().out() as downloaded content?
>> >
>> >
>> > Thanks
>> >
>> >
>> > Mawan
>> >
>> >
>> >
>> ------------------------------------------------------------------------------
>> > Transform Data into Opportunity.
>> > Accelerate data analysis in your applications with
>> > Intel Data Analytics Acceleration Library.
>> > Click to learn more.
>> > http://pubads.g.doubleclick.net/gampad/clk?id=278785351&iu=/4140
>> >
>> >
>> >
>> > _______________________________________________
>> > Cppcms-users mailing list
>> > Cpp...@li...
>> > https://lists.sourceforge.net/lists/listinfo/cppcms-users
>> >
>>
>>
>>
>> ------------------------------------------------------------------------------
>> Transform Data into Opportunity.
>> Accelerate data analysis in your applications with
>> Intel Data Analytics Acceleration Library.
>> Click to learn more.
>> http://pubads.g.doubleclick.net/gampad/clk?id=278785351&iu=/4140
>> _______________________________________________
>> Cppcms-users mailing list
>> Cpp...@li...
>> https://lists.sourceforge.net/lists/listinfo/cppcms-users
>>
>>
>

Re: [Cppcms-users] read file and download it

[mawan s. <ma...@gm...>]

Thankyou Marcel.



On Wed, Mar 23, 2016 at 6:07 AM, Marcel Hellwig <ke...@co...> wrote:

> just don't
>
> http://cppcms.com/wikipp/en/page/cppcms_1x_serving_static_files
>
> On 03/21/2016 07:56 AM, mawan sugiyanto wrote:
> > Dear All
> >
> > how to read file and put on response().out() as downloaded content?
> >
> >
> > Thanks
> >
> >
> > Mawan
> >
> >
> >
> ------------------------------------------------------------------------------
> > Transform Data into Opportunity.
> > Accelerate data analysis in your applications with
> > Intel Data Analytics Acceleration Library.
> > Click to learn more.
> > http://pubads.g.doubleclick.net/gampad/clk?id=278785351&iu=/4140
> >
> >
> >
> > _______________________________________________
> > Cppcms-users mailing list
> > Cpp...@li...
> > https://lists.sourceforge.net/lists/listinfo/cppcms-users
> >
>
>
>
> ------------------------------------------------------------------------------
> Transform Data into Opportunity.
> Accelerate data analysis in your applications with
> Intel Data Analytics Acceleration Library.
> Click to learn more.
> http://pubads.g.doubleclick.net/gampad/clk?id=278785351&iu=/4140
> _______________________________________________
> Cppcms-users mailing list
> Cpp...@li...
> https://lists.sourceforge.net/lists/listinfo/cppcms-users
>
>

Re: [Cppcms-users] read file and download it

[Marcel H. <ke...@co...>]

just don't

http://cppcms.com/wikipp/en/page/cppcms_1x_serving_static_files

On 03/21/2016 07:56 AM, mawan sugiyanto wrote:
> Dear All 
> 
> how to read file and put on response().out() as downloaded content?
> 
> 
> Thanks 
> 
> 
> Mawan
> 
> 
> ------------------------------------------------------------------------------
> Transform Data into Opportunity.
> Accelerate data analysis in your applications with
> Intel Data Analytics Acceleration Library.
> Click to learn more.
> http://pubads.g.doubleclick.net/gampad/clk?id=278785351&iu=/4140
> 
> 
> 
> _______________________________________________
> Cppcms-users mailing list
> Cpp...@li...
> https://lists.sourceforge.net/lists/listinfo/cppcms-users
> 

[Cppcms-users] read file and download it

[mawan s. <ma...@gm...>]

Dear All

how to read file and put on response().out() as downloaded content?


Thanks


Mawan

Re: [Cppcms-users] Lots of files to be uploaded

[Artyom B. <art...@gm...>]

> Hi,
>
> Say I want to write a distributed blob store on top of hdfs using
> libhdfs. CppCMS will be used for authentication and other validation
> purposes for example file size and type.
>
> If I reverse proxy this behind Nginx then do I need to specifically
> take care about asynchronous IO?
>
> --
> Respect,
> Shiv Shankar Dayal
>

File uploading is performed in asynchronous event loop
independently and automatically.

In CppCMS 1.0.x you'll get notification about uploaded
file only once it is ready - so no special stuff needed.

But CppCMS 1.1 (future 1.2) provides much improved interface
to handle uploads:

http://cppcms.com/wikipp/en/page/cppcms_1_2_filtering

It would allow you to improve file handling significantly:

1. Allow performing authentication/authorization before the entire
file gets uploaded
2. Process file content during the process and for example validate it.

So if you want to you can use it.

2nd is make sure Nginx does not cache incoming POST data but transfers
it directly to CppCMS process.

Artyom

[Cppcms-users] Lots of files to be uploaded

[Shiv S. D. <shi...@gm...>]

Hi,

Say I want to write a distributed blob store on top of hdfs using
libhdfs. CppCMS will be used for authentication and other validation
purposes for example file size and type.

If I reverse proxy this behind Nginx then do I need to specifically
take care about asynchronous IO?

-- 
Respect,
Shiv Shankar Dayal

Re: [Cppcms-users] Simple user/password authentication with CppCMS-Embedded server

[Artyom B. <art...@gm...>]

CppCMS does not currently provide built in HTTP authentication.

However it shouldn't be too hard to implement:

https://en.wikipedia.org/wiki/Digest_access_authentication
https://en.wikipedia.org/wiki/Basic_access_authentication


Artyom

On Thu, Mar 17, 2016 at 9:39 AM, piotr.lewicki <pio...@el...> wrote:
> Hello,
> I'm creating a simple web interface for my embedded device.
> I have done it using GNU cgicc and used lighttpd server, but now I would
> like to switch to CppCMS because it has it's own server (CppCMS-Embedded).
> For now everything looks perfect and working with it is very nice but
> I'm missing one feature which is a user/password authentication.
>
> On my previous setup I used lighty's "mod_auth" for it but since I want
> to get rid of lighttpd - I need this in CppCMS.
> I searched for it but couldn't find anything.
>
> Could you help me with coming up with a solution?
> How can I implement simple user/password authentication for CppCMS
> application?
>
> Thanks,
> Piotr Lewicki
>
> ------------------------------------------------------------------------------
> Transform Data into Opportunity.
> Accelerate data analysis in your applications with
> Intel Data Analytics Acceleration Library.
> Click to learn more.
> http://pubads.g.doubleclick.net/gampad/clk?id=278785231&iu=/4140
> _______________________________________________
> Cppcms-users mailing list
> Cpp...@li...
> https://lists.sourceforge.net/lists/listinfo/cppcms-users

Re: [Cppcms-users] detect memory usage

[Joerg S. <jo...@br...>]

On Wed, Mar 16, 2016 at 10:32:24AM -0500, Ryan Gonzalez wrote:
> Try checking out Valgrind. You can do:
> 
> $ valgrind --leak-check=full --show-leak-kinds=all my_application
> 
> and it'll show you any memory leaks.

Note that if you are primarily interested in memory statistics only,
Google Performance Tools might be a better choice since they are at
least an order of magnitude faster.

Joerg

[Cppcms-users] Simple user/password authentication with CppCMS-Embedded server

[piotr.lewicki <pio...@el...>]

Hello,
I'm creating a simple web interface for my embedded device.
I have done it using GNU cgicc and used lighttpd server, but now I would 
like to switch to CppCMS because it has it's own server (CppCMS-Embedded).
For now everything looks perfect and working with it is very nice but 
I'm missing one feature which is a user/password authentication.

On my previous setup I used lighty's "mod_auth" for it but since I want 
to get rid of lighttpd - I need this in CppCMS.
I searched for it but couldn't find anything.

Could you help me with coming up with a solution?
How can I implement simple user/password authentication for CppCMS 
application?

Thanks,
Piotr Lewicki

Re: [Cppcms-users] detect memory usage

[mawan s. <ma...@gm...>]

Thankyou Ryan



On Wed, Mar 16, 2016 at 10:32 PM, Ryan Gonzalez <ry...@gm...> wrote:

> Try checking out Valgrind. You can do:
>
> $ valgrind --leak-check=full --show-leak-kinds=all my_application
>
> and it'll show you any memory leaks.
>
> --
> Ryan
> [ERROR]: Your autotools build scripts are 200 lines longer than your
> program. Something’s wrong.
> http://kirbyfan64.github.io/
> On Mar 16, 2016 5:24 AM, "mawan sugiyanto" <ma...@gm...> wrote:
>
>> Dear All
>>
>> I try run cppcms application from http configuration. not as cgi.
>>
>> this application consume increasing from 1.2MB at start and increase to
>> 16.5MB.
>>
>> can i detect and clear memory?
>>
>>
>> Thankyou
>>
>>
>> Mawan
>>
>>
>> ------------------------------------------------------------------------------
>> Transform Data into Opportunity.
>> Accelerate data analysis in your applications with
>> Intel Data Analytics Acceleration Library.
>> Click to learn more.
>> http://pubads.g.doubleclick.net/gampad/clk?id=278785231&iu=/4140
>> _______________________________________________
>> Cppcms-users mailing list
>> Cpp...@li...
>> https://lists.sourceforge.net/lists/listinfo/cppcms-users
>>
>>
>
> ------------------------------------------------------------------------------
> Transform Data into Opportunity.
> Accelerate data analysis in your applications with
> Intel Data Analytics Acceleration Library.
> Click to learn more.
> http://pubads.g.doubleclick.net/gampad/clk?id=278785231&iu=/4140
> _______________________________________________
> Cppcms-users mailing list
> Cpp...@li...
> https://lists.sourceforge.net/lists/listinfo/cppcms-users
>
>

Re: [Cppcms-users] detect memory usage

[Ryan G. <ry...@gm...>]

Try checking out Valgrind. You can do:

$ valgrind --leak-check=full --show-leak-kinds=all my_application

and it'll show you any memory leaks.

--
Ryan
[ERROR]: Your autotools build scripts are 200 lines longer than your
program. Something’s wrong.
http://kirbyfan64.github.io/
On Mar 16, 2016 5:24 AM, "mawan sugiyanto" <ma...@gm...> wrote:

> Dear All
>
> I try run cppcms application from http configuration. not as cgi.
>
> this application consume increasing from 1.2MB at start and increase to
> 16.5MB.
>
> can i detect and clear memory?
>
>
> Thankyou
>
>
> Mawan
>
>
> ------------------------------------------------------------------------------
> Transform Data into Opportunity.
> Accelerate data analysis in your applications with
> Intel Data Analytics Acceleration Library.
> Click to learn more.
> http://pubads.g.doubleclick.net/gampad/clk?id=278785231&iu=/4140
> _______________________________________________
> Cppcms-users mailing list
> Cpp...@li...
> https://lists.sourceforge.net/lists/listinfo/cppcms-users
>
>

[Cppcms-users] detect memory usage

[mawan s. <ma...@gm...>]

Dear All

I try run cppcms application from http configuration. not as cgi.

this application consume increasing from 1.2MB at start and increase to
16.5MB.

can i detect and clear memory?


Thankyou


Mawan

Re: [Cppcms-users] CppDB: SQL Parameter for IN clause

[CN <cn...@fa...>]

On Wed, Mar 16, 2016, at 01:47 PM, Artyom Beilis wrote:
> First of all sorry for delayed reply - was offline for a while.

I am much grateful for your kind helps and marvelous CppCMS products.
 
> What I did in such a case I build manually a query with several
> placeholders
> according to number of iterms in IN clause and binded prameters later i.
> 
> 
> sql << "SELECT 1 FROM t WHERE c IN (?)" << 1 ;
> sql << "SELECT 1 FROM t WHERE c IN (?,?)" << 1 << 2;
> 
> and so on.
> 
> Currently there is no special placeholder for a variable number of
> parameters in CppDB

Your approach makes me think that there actually is no one-size-fit-all
solution for such use case. It looks like that the best I can do now is
to run time generate SQL text with variable number of question marks in
"IN ()" clause if I want the SQL to accept random number of values from
end users and then loop to bind these values to these question marks.

Thanks for the comments! 

Best Regards,
CN

-- 
http://www.fastmail.com - The professional email service

Re: [Cppcms-users] Problem with Server Side Events

[Artyom B. <art...@gm...>]

> I want is to be able to clear SSE events that have been sent but can't
> figure out how to do that. Who knows how to do this?
>

See from the code below you use Status Stream - which gives always the
latest status for a given situation. (if your code is based on my SSE)

If you disconnect/reconnect you'll get the latest status in your case if it
is a message popup than you'll get in after disco.

So for messages queue that tracks what was sent is more suitable.

> Furthermore I notice that connections are lost about every 30 seconds, which
> seems to be some regulated timeout. Where is that configured? The other
> thing I notice is that sometimes SSE events are sent without content and
> without me initiating them. Where do these come from?
>

There should be some keep-alive messages, regarding 30 seconds.

Take a look on http://cppcms.com/wikipp/en/page/cppcms_1x_config#http.timeout

Also it is strange as it should not occur on "detached" connections so
you can handle timeouts on your own.

Artyom

Re: [Cppcms-users] CppDB: SQL Parameter for IN clause

[Artyom B. <art...@gm...>]

First of all sorry for delayed reply - was offline for a while.

>
> I do not simply add this question as a feature request to CppDB project
> site because I am not sure whether or not I am asking too much or there
> actually are workarounds of this issue.
>
> Say I have this SQL:
>
> SELECT 1 FROM t WHERE c IN (?)
>
> Users might enter the following values for the "?" inside the
> parentheses:
>
> 'a','b','c'
> 2,3,4
>
> and expect they faithfully replace the question mark as they are.

That is wrong assumption.

The ? is translated to a placeholder of the specific library in Sqlite
and MySQL it
would be "?" and in PosgreSQL it would be AFAIR $1, $2 etc.

Than you bind a value to a single element so if you bind a string like
'a','b','c' it
would effectively be IN('''a''.''b''.''c''') i.e. a single string.

>
> However, if I am correct, working with PostgreSQL libpq, the current
> implementation of CppDB and another database connection product not
> belonging to CppCMS products tend to incorrectly send the final SQL to
> PostgreSQL server like so:
>
> SELECT 1 FROM t WHERE c IN ('<v>')
>
> , where <v> is a character string which can be one of the following two
> values
>
> 'a','b','c'
> 2,3,4
>
> with all single quotes properly escaped, if any. Although the ultimate
> SQL is valid, it yields wrong query result.
>

Note the parameters aren't "injected" to query directly but rather binder
by a library to a statement.

> How do you folks handle such corner case? Is this issue supposed to be
> handled on application level or database connection component level?

What I did in such a case I build manually a query with several placeholders
according to number of iterms in IN clause and binded prameters later i.


sql << "SELECT 1 FROM t WHERE c IN (?)" << 1 ;
sql << "SELECT 1 FROM t WHERE c IN (?,?)" << 1 << 2;

and so on.

Currently there is no special placeholder for a variable number of
parameters in CppDB

Artyom

[Cppcms-users] CppDB: SQL Parameter for IN clause

[CN <cn...@fa...>]

Hi!

I do not simply add this question as a feature request to CppDB project
site because I am not sure whether or not I am asking too much or there
actually are workarounds of this issue.

Say I have this SQL:

SELECT 1 FROM t WHERE c IN (?)

Users might enter the following values for the "?" inside the
parentheses:

'a','b','c'
2,3,4

and expect they faithfully replace the question mark as they are.

However, if I am correct, working with PostgreSQL libpq, the current
implementation of CppDB and another database connection product not
belonging to CppCMS products tend to incorrectly send the final SQL to
PostgreSQL server like so:

SELECT 1 FROM t WHERE c IN ('<v>')

, where <v> is a character string which can be one of the following two
values

'a','b','c'
2,3,4

with all single quotes properly escaped, if any. Although the ultimate
SQL is valid, it yields wrong query result.

How do you folks handle such corner case? Is this issue supposed to be
handled on application level or database connection component level?

Thank you in advance for any input!

Best Regards,
CN

-- 
http://www.fastmail.com - Access all of your messages and folders
                          wherever you are

Re: [Cppcms-users] form validation

[Sergey <dan...@gm...>]

You can also use like this:

<% c++ if (content.app().request().request_method() == "POST") { %>

<% if not form.name.valid() %>
    Message error here
<% end %>

<% c++ } %>

Re: [Cppcms-users] form validation

[Rodrigo E. <rod...@gm...>]

Hi Mawan,

I don't have yet a complete knowledge about the api of CppCms. But I use it
in very simple form. When you have a validation error in an element (aka: a
subclass of cppcms::widgets::base_widget), the state of this element become
invalid. This invalidity may occur in a manual validation overloading of
the validate() method, or automatic validation, when you use   a method
like cppcms::widgets::base_widget::base_text.non_empty(), and the element
is submited blank.
In the view you can access the method cppcms::base_form.valid() of
cppcms::widgets::base_widget like that:

<% if not form.name.valid() %>
    Message error here
<% end %>

I hope that could be  useful for your doubt and sorry about my English.

Rodrigo Emygdio

2016-02-24 7:05 GMT-03:00 mawan sugiyanto <ma...@gm...>:

> Dear All
>
>
> if i get form validation false, what can i do to make sure where is the
> error type or which element has error?
>
> Thanks
>
>
> Mawan
>
>
> ------------------------------------------------------------------------------
> Site24x7 APM Insight: Get Deep Visibility into Application Performance
> APM + Mobile APM + RUM: Monitor 3 App instances at just $35/Month
> Monitor end-to-end web transactions and take corrective actions now
> Troubleshoot faster and improve end-user experience. Signup Now!
> http://pubads.g.doubleclick.net/gampad/clk?id=272487151&iu=/4140
> _______________________________________________
> Cppcms-users mailing list
> Cpp...@li...
> https://lists.sourceforge.net/lists/listinfo/cppcms-users
>
>

[Cppcms-users] form validation

[mawan s. <ma...@gm...>]

Dear All


if i get form validation false, what can i do to make sure where is the
error type or which element has error?

Thanks


Mawan