Ruby gems are Ruby programs and libraries with a name, version and the platform that can execute them. List the installed gems on your system gem list Detailed list that includes the author, homepage, license, install location and a short description gem list -d Install the latest version of the gem gem install GEM_NAME Install a …
Author Archives: Laszlo Pinter
Bootstrap Chef nodes to connect them to the Chef server
A Chef node is a physical or virtual machine with an operating system that is connected to the Chef server. Once the node has made the connection to the Chef server, the installed Chef Client can execute Chef cookbooks to configure the machine. Bootstrapping is the process to connect the node the first time to …
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Dynamically set Chef resource attributes
When you need to set a Chef resource attribute based on the current state of the environment, there is a way to dynamically provide the value. Set the value of a boolean variable with a test, Declare the Chef resource and assign a reference to it to a variable, Set the resource attribute based on …
How to create a bootable USB drive to install Windows
If the computer you want to install Microsoft WIndows on, does not have a DVD drive, you can install Windows from a USB drive. To start the computer from the USB drive, you need to prepare the drive to make it bootable. Microsoft has a free tool that can download the edition of the Windows …
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Setup failed: Failed to copy slug dir: lstat /Users: no such file or directory error in Terraform Enterprise
When you try to execute a Terraform configuration in Terraform Enterprise (Atlas) you may get the error message: Setup failed: Failed to copy slug dir: lstat /Users: no such file or directory Cause: The Git repository contains the .terraform/modules directory, and the Terraform Enterprise server cannot get the latest modules from GitHub. Solution: Create a .gitignore file …
Install a Python package
To install a Python package on Macintosh Download the Python package to your workstation, Unpack the package, Open a terminal window, Start sudo, sudo -i Change to the directory of the package, Install the package. pip install PACKAGE_NAME If you don’t install the package in sudo mode, you will get “Permission denied” errors during the …
PyCharm configuration
When you install PyCharm, the default Python interpreter is may not the version you want to use for your new projects. When you create a new project, and the project interpreter is not set, you may get the following error message: Executed command: /var/folders/_x/_f0zzs1s4sx6bk4s8n78l2jsbn9r3z/T/tmpBoQLx_pycharm-management/pip-9.0.1/setup.py install Error occurred: 40:357: execution error: /System/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/distutils/dist.py:266: UserWarning: Unknown distribution option: …
IronPython
IronPython can expose Python types to C# libraries, and expose C# libraries to Python code.
Python ImportError: No module named …
Symptom: from MY_FOLDER.MY_FILE import MY_CLASS causes an error: ImportError: No module named MY_FOLDER.MY_FILE Debugging: Execute the program in debug mode, In the Variables window expand Special Variables, Read the __warningregistry__ value. Possible cause: The __init__.py file is missing in the directory of the referenced class. Solution: Create an empty __init__.py file in the directory where the class is referenced …
Python basics
Great Python introductory video for C# developers https://www.youtube.com/watch?v=jj60geqaP08 __ (double underscore) Starting the attribute name with double underscore attribute makes it private. To expose the private attributes and methods print(dir(MY_CLASS)) Code hierarchy In Python indentation denotes the hierarchy of the instructions, not curly braces, like in C# or Java. Directories When you create a directory …