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Build Wine rpm with 32 bit application support

Wine is a software to allow running Windows applications in Linux, MAC etc. platforms. It is available for installation from package managers like yum (RHEL, CentOS) and apt (Ubuntu). You can find more details on how it works in Wine wiki . But the default Wine package available from package manager does not have support for 32 bit Windows applications. This was the case for me. In Redhat Enterprise Linux 7.3, the wine package did not contain support for 32 bit windows applications. So the only option was to build a separate rpm of wine which will include this support. All the steps are executed on a RHEL 7.3 VM (x86_64). Step 1 Download and run shell script which will make wine 64 and 32 support for RHEL: https://github.com/zma/usefulscripts/blob/master/script/install-wine-i686-centos7.sh It accepts a version no. as CLI parameter e.g. 2.0.3 The script installs wine in /usr/local/ directory by default. We can verify the files that are being copied for wine using "...
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Simple employee table with OpenStack Horizon DataTable module

I was working on OpenStack dashboard (aka Horizon ) few past few months and I will share a simple way to build your data tables based on Horizon. To give a brief introduction of Horizon, it is the official dashboard project of OpenStack, the cloud operating system. Horizon is a python Django application. It provides pre-defined modules for common web application requirements like tabs, workflow, table etc. From Grizzly release onward Horizon modules are separated from OpenStack specific code. It allows one to use Horizon modules independently. To build a data table in Horizon you need to simply create a model class for your data. The important thing to remember here is that the class must have an "id" attribute . Horizon will build rows based on this id. It can be alpha numeric also. Though it is not mandatory to display the id column in the table, you can still have it. Below is the data model for my Employee table - The employee class has 4 attributes -...
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Get current UTC timestamp in Python

Converting current time to UTC (GMT) in python is a very common query that is searched in Google but, I did not find a compact answer when I did the search for my work. I figured out the code by some help from Google and some experimentation of my own. I'll share the code, in case it is useful to someone. First I'll explain the Epoch time (or POSIX/Unix time) and UTC (Coordinated Universal Time) time format. Epoch time is calculated as number of seconds elapsed since midnight Jan 1, 1970. It is used in all *nix systems and has become a standard when considering date/time from multiple systems. In python time module allows us to get the current epoch time in local time zone. UTC time is basically synonymous of GMT. It marks the 0 offset time zone. Time in all other time zones are calculated with positive/negative offset from UTC. It is used in many cases where there are multiple machines, located in different time zones are involved. To get current UTC time in python we ...
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Read a log file in tail mode from python

When you want to develop a log reader application, you'll need to keep reading the log. There is a Linux utility doing exactly the same. Its the tail command. tail blocks on the file till new entries are appended to it. I needed the similar functionality in python and there was a small library providing it already. Its called filetail.py . The program performs tail functionality and also handles log rotation. But in my case, the log file used to change (file name) depending on the date. filetail could not handle it as the file name has changed already. To handle this I have made following changes to the filetail code - In nextline() method file size should be checked to be less or equal to the cursor position: In _reset() method I have added the logic to re-create the log file name from the current date value and replace it with the original file name: I apologize for not following standards of coding here. It served the purpose for me.
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Run Cherrypy web server in Android

I was in much need of a way to run Python CGI scripts in Android. Basically I needed a web server capable of running CGI scripts in Android platform but, I found none. Finally I modified my CGI script to suit the Cherrypy web server and it could run on Android. I'll try to describe the steps here which I had to figure out myself. The information I found by googling was not completely correct as Android platform has changed from the time of the publication. So, I'll mention the version no. for each software I've used to make sure it is not misunderstood later. First thing we need is to download the SL4A (r4) software in the Android (2.3) emulator. It can be done from your Android browser by going to the SL4A site . Now install the software in emulator. Then install Python for Android from the same SL4A site. It'll download an apk of version r4. Launch SL4A application and check that HelloWorld python script is running. It will make sure that your installation is...
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