Custom Implementing multileg option orders in QuickFIX 4.2 - c++

Multileg option orders are not supported in FIX Protocol 4.2. I've implemented custom tags but never a new message type. Can anyone provide a roadmap of the steps to implement NewOrderMultileg msgtype="AB" into the QuickFix FIX42 namespace?

This should help or more or less this is how you do it. It is for QuickFIX/N, but the method of adding new messages is consistent for all Quickfix libraries.
Or another way is hijack it from the data dictionary for the FIX version where it exists. I believe all versions of the data dictionary are in the quickfix releases. But you need to be careful how you do it i.e. check for fields, repeating group etc.
But you might have to add some code if the new message class doesn't exist at all and you will have to engineer it to fit in your existing library. This might need some work and may throw up some unlikely errors. For this you can easily refer to a quickfix library version which does have the class.

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Best practice for creating an unalterable report file in c++

I am currently developping a windows application who test railroad equipments to find any defaults.
Utility A => OK
Utility B => NOK
...
This application will check the given equipment and generate a report.
This report needs to be written once, and no further modifications are allowed since this file can be used as working proof for the equipment.
My first idea was ta use pdf files (haru lib looks great), but pdf can also be modified.
I told myself that I could obsfuscate the report, and implement a homemade reader inside my application, but whatever way I store it, the file would always be possibly accessed and modified right?
So I'm running out of ideas.
Sorry if my approach and my problem appear naive but it's an intership.
Thanks for any help.
Edit: I could also add checksums for files after I generated them, and keep a "checksums record file", and implement a checksums comparison tool for verification? just thought about this.
I believe the answer to your question is to use any format whatosever, and use a digital signature anybody can verify, e.g., create a gnupg, get that key signed by the people who require to check your documents, upload it to one of the key servers, and use it to sign the documents. You can publish the documents, and have a link to your public key available for verification; for critical cases someone verifying must be trust your signature (i.e., trust somebody who signed your key).
People's lives depend on the state of train inspections. Therefore, I find it hard to believe that someone expects you to solve this problem only using free-as-in-beer components.
Adobe supports a strong digital signature model. If you buy into their technology base, you can create PDF's that are digitally signed, and are therefore tamper-evident, as the consumer can check for the signature.
You can, as someone else pointed out, use GNUpg, or for that matter OpenSSL, to implement your own signature scheme, but railroad regulators are somewhat less likely to figure out how to work with it.
I would store reports in an encrypted/protected datastore.
When a user accesses a report (requests a copy, the original is of course always in the database and cannot be modified), it includes the text "Report #XXXXX". If you want to validate the report, retrive a new copy from the system using the Report ID.

How to parse HTML with C++/Qt?

How can i parse the following HTML
<body>
<span style="font-size:11px">12345</span>
<a>Hello<a>
</body>
I would like to retrive the data "12345" from a "span" with style="font-size:11px" from www.testtest.com, but I only want the that very data, and nothing else.
How can I accomplish this?
I think QXmlQuery is what you want.
I think the code will be like
QXmlQuery query;
query.setQuery(html, QUrl("/body/span[#style='font-size:11p']"));
QString r;
query.evaluateTo(&r);
You can also provide URL directly to the query
query.setQuery(QUrl("http://WWW.testtest.com"), QUrl("/body/span[#style='font-size:11p']"));
EDIT: From the Qt 5.6 release blog post:
With 5.6, Qt WebKit and Qt Quick 1 will no longer be supported and are dropped from the release. The source code for these modules will still be available.
So, as of Qt 5.6 – unless you're willing to compile the sources –, QtWebKit is no longer available. If you're using a Qt release older than 5.6 ot are willing to compile QtWebKit, this might be helpful; otherwise this answer is no longer valid.
It is hard to tell you exactly what needs to be done as your explanation is incomplete about the use case. However, there are two ways of proceeding.
QtWebKit
If you already need any other functionality from that module, this is not going to introduce any further dependencies, and it will be the most convenient for you to use.
You need to get the https://doc.qt.io/archives/qt-5.5/qwebelement.html
That will come once you find the first "span" element in your html:
https://doc.qt.io/archives/qt-5.5/qwebframe.html#findFirstElement
Then, you can simply get the text for that element with the corresponding QWebElement method(s). For instances, you can use this one for getting an attribute value:
https://doc.qt.io/archives/qt-5.5/qwebelement.html#attribute
... but you can also request the attribute names as you can see in the documentation, etc.
This is how you will get the 12345 value:
https://doc.qt.io/archives/qt-5.5/qwebelement.html#toPlainText
XML parser in QtCore
If you do not need webkit for your sotware, and the html data comes in a different way rather than directly from the web for which you would need to use QWebKit, then you are better off using the xml parser available in QtCore. It still might be the case even if you do not have any other dependency from QtWebKit that this additional dependency will not cause any issues in your use case. It is hard to tell based upon your description. For sure, this would be less convenient, albeit not that much, compared to the webkit based solution as that is designed for html.
What you need to avoid is QtXmlPatterns. It is an unmaintained software as of now, and that would introduce an additional dependency for your code either way.

Design approaches to read/write different version of same config file

In our project we got an application that uses an external configuration file (say server.xml). Now we need to design a setup tool GUI in C++/QT to read/edit such configuration file and it should be able to handle all the different versions of such file. The user will choose the file version and then proceed with the editing. From one version to another doesn't change too much, maybe there is a new xml tag, a tag with a different name or in a different position.
What's the best design approach to do so? We are planning to go for a standard MVC design pattern but how to deal with all the different configuration versions without rewriting the same GUI code again n again?
Here the sample config file:
<?xml version="1.0" encoding="utf-8"?>
<Server_configuration ver="11">
<core>
<enable-tms>true</enable-tms>
<enable-gui-messages>true</enable-gui-messages>
<waiting-for-config-timeout>10000</waiting-for-config-timeout>
<remoting>
<port>50000</port>
<join-timeout>5000</join-timeout>
<ismultithread>true</ismultithread>
<maxconcurrentrequests>20</maxconcurrentrequests>
</remoting>
</core>
<content>
<ftp>
<ip>192.168.0.227</ip>
<port>21</port>
<userid>******</userid>
<passwd>******</passwd>
</ftp>
<library>
<ip>192.168.0.227</ip>
<port>50023</port>
</library>
<local>
<asset-root>/assetroot</asset-root>
<kdm-expiration-warning>172800000</kdm-expiration-warning>
</local>
<hula-store-daemon>
<ip>127.0.0.1</ip>
<port>5567</port>
</hula-store-daemon>
</content>
</Server_configuration>
This is no means a drop in solution but I here are some things to do/consider. Every situation will differ.
Have an explicit version identifier in your config files. Fingerprinting them is a real (error prone) pain.
Consider having a tool that will update from version to version. It will be easier than reading old versions and trying to apply them.
I may be easier to do every version step individually but this can make the conversions less "lossless". A happy hybrid is to do minor updates from version to version but have "checkpoint" major upgrades that will jump right to the latest (or the latest "checkpoint"). This is kinda like incremental backups with full backup snapshots every once and a while.
Keep the user informed. A sysadmin won't be happy if you are changing his settings. You might want to make the process interactive or put comments into the file of every added/moved/removed setting. I would also recommend keeping removed settings in some section of the file for user reference. (Put a note why they are there as well).
Backup the old file. Your script will crash and it will eat data. Do something like naming the current file ${oldname}.old-${ver}~. Saving the settings in a different section of the file won't always be enough and this will save your users a lot of heartache.
Versioning should always be designed as robust and as simple as possible. It is crucial for you to determine whether each version of your application must be compatible with each version of the setup tool (which is rare), or whether you can, for example, meet your needs if any newer setup tool works with any same or older application, but not vice versa.
One way compatibility
One possibility to design for the latter is to add a version attribute to the XML file but try to keep it at the same fixed value forever by always only changing the structure and semantics of the XML file in backward compatible ways. For example, adding an element is backward compatible as long as the setup tool can interpret its absence the same way both the old setup tool and the application would behave. It does not hurt that the new setup tool always writes an (equivalent) value to the new element, because two-way compatibility with the old application is not required.
Once the day comes when you cannot maintain backward compatibility on input, you just change the value of the version attribute and start special casing it in the setup tool.
If you validate the XML against an XSD, notice that XSD can actually do one frequently useful thing for you: assign default attribute values. This way, your setup tool's source code may not even actually notice that the underlying document was missing a recently added attribute!
Two way compatibility
Strict versioning is needed. A schema definition (XSD, RelayNG,...) should be defined for each version of the XML file and the file should be validated against it both when it is read by the setup tool, written by the setup tool, or read by the application. The schema definition may be identical for several consecutive versions, if the interpretation of the same XML has changed, so when in doubt, always increase the version number.
Do what you can educating everyone that they cannot just edit the latest schema and do away with that. Unreliable versioning is worse than no versioning.

How to avoid csc.exe being called from runtime in sharepoint 2010

I have seen some posts that mention the xmlserializer being called at runtime in .Net.
I have a sharepoint web-part that calls a webservice to retrieve data, and then is supposed to display that data on the web-part. But I get this error:
System.Runtime.InteropServices.ExternalException: Cannot execute a program. The command being executed was "C:\Windows\Microsoft.NET\Framework64\v2.0.50727\csc.exe" /noconfig /fullpaths #"C:\Users\my_deploy_spFarm_user\AppData\Local\Temp\OICE_356C17F3-2ED2-423C-8BBE-CA5C05740FD7.0\eelwfhnn.cmdline
Now the posts I have read here, state that the problem is that the compiler is trying to to create an XML serialization assembly on the fly, but does not have privilege to do so.
I have seen some suggestions to use the post-build events to create this XML Serialization Assembly at Compile-time. However I am not sure of how to do that, and also I am not sure if this assemply would get included in the .wsp package?
I'd take a good look at whether you really want the full, automatically generated serializer, or whether you just want to emit/parse some relatively straightforward XML - if the latter, you'll solve this problem by not using stuff that needs generated code, i.e. use the XmlReader/XmlWriter directly.
This link has the basic command to create the pre-compiled serializers.

Wix: How to add files to the RemoveFiles table from c++

I've been following the advice in this question.
How to add a WiX custom action that happens only on uninstall (via MSI)?
I have an executable running as a custom action after InstallFinalize which I intend to purge all my files and folders. I was just going to write some standard deletion logic but I'm stuck on the point that Rob Mensching made that the windows installer should handle this incase someone bails midway through an uninstallation.
"create a CustomAction that adds temporary rows to the RemoveFiles table"
I'm looking for some more information on this. I'm not really sure how to achieve this in c++ and my searching hasn't turned up a whole lot.
http://msdn.microsoft.com/en-us/library/windows/desktop/aa371201(v=vs.85).aspx
Thanks
Neil
EDIT: I've marked the answer due to the question being specific about how to add files to the removeFiles table in c++ however I'm inclined to agree that the better solution is to use the RemoveFolderEx functionality in wix even though it is currently in beta (3.6 I think)
Roughly you will have to use the following functions in this order:
MsiDatabaseOpenView - the (input) handle is the one you get inside your custom action functions
MsiCreateRecord - to create a record with the SQL stuff inside
MsiRecord* - set of functions to prepare the record
MsiViewExecute to insert the new record into whatever table you please ...
MsiCloseHandle - with the handle from the very first step and the record handle (from MsiCreateRecord)
Everything is explained in detail over at MSDN. However, pay special attention to the section "Functions Not for Use in Custom Actions".
The documentation of MsiViewExecute also explains how the SQL queries should look. To get a feel for them you may want to use one of the .vbs scripts that are part of the Windows Installer SDK.
If you use WiX to create your installation package, consider using RemoveFolderEx element. It does what you want and you don't have to write the code yourself.
Read Tactical directory nukes for an example of how to use it.
If you still want to implement it yourself, you can get your inspiration from this blog post, there's the code for doing this in VBScript.