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      How To Install Go and Set Up a Local Programming Environment on macOS


      Introduction

      Go is a programming language that was born out of frustration at Google. Developers continually had to pick a language that executed efficiently but took a long time to compile, or to pick a language that was easy to program but ran inefficiently in production. Go was designed to have all three available at the same time: fast compilation, ease of programming, and efficient execution in production.

      While Go is a versatile programming language that can be used for many different programming projects, it’s particularly well suited for networking/distributed systems programs, and has earned a reputation as “the language of the cloud.” It focuses on helping the modern programmer do more with a strong set of tooling, removing debates over formatting by making the format part of the language specification, as well as making deployment easy by compiling to a single binary. Go is easy to learn, with a very small set of keywords, which makes it a great choice for beginners and experienced developers alike.

      This tutorial will guide you through installing Go on your local macOS machine and setting up a programming workspace via the command line.

      Prerequisites

      You will need a macOS computer with administrative access that is connected to the internet.

      Step 1 — Opening Terminal

      We’ll be completing most of our installation and setup on the command line, which is a non-graphical way to interact with your computer. That is, instead of clicking on buttons, you’ll be typing in text and receiving feedback from your computer through text as well. The command line, also known as a shell, can help you modify and automate many of the tasks you do on a computer every day, and is an essential tool for software developers.

      The macOS Terminal is an application you can use to access the command line interface. Like any other application, you can find it by going into Finder, navigating to the Applications folder, and then into the Utilities folder. From here, double-click the Terminal like any other application to open it up. Alternatively, you can use Spotlight by holding down the CMD and SPACE keys to find Terminal by typing it out in the box that appears.

      macOS Terminal

      There are many more Terminal commands to learn that can enable you to do more powerful things. The article “An Introduction to the Linux Terminal” can get you better oriented with the Linux Terminal, which is similar to the macOS Terminal.

      Now that you have opened up Terminal, you can download and install Xcode, a package of developer tools that you will need in order to install Go.

      Step 2 — Installing Xcode

      Xcode is an integrated development environment (IDE) that is comprised of software development tools for macOS. You can check if Xcode is already installed by typing the following in the Terminal window:

      The following output means that Xcode is installed:

      Output

      /Library/Developer/CommandLineTools

      If you received an error, then in your web browser install Xcode from the App Store and accept the default options.

      Once Xcode is installed, return to your Terminal window. Next, you’ll need to install Xcode’s separate Command Line Tools app, which you can do by typing:

      At this point, Xcode and its Command Line Tools app are fully installed, and we are ready to install the package manager Homebrew.

      Step 3 — Installing and Setting Up Homebrew

      While the macOS Terminal has a lot of the functionality of Linux Terminals and other Unix systems, it does not ship with a package manager that accommodates best practices. A package manager is a collection of software tools that work to automate installation processes that include initial software installation, upgrading and configuring of software, and removing software as needed. They keep installations in a central location and can maintain all software packages on the system in formats that are commonly used. Homebrew provides macOS with a free and open source software package managing system that simplifies the installation of software on macOS.

      To install Homebrew, type this into your Terminal window:

      • /usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

      Homebrew is made with Ruby, so it will be modifying your computer’s Ruby path. The curl command pulls a script from the specified URL. This script will explain what it will do and then pauses the process to prompt you to confirm. This provides you with a lot of feedback on what the script is going to be doing to your system and gives you the opportunity to verify the process.

      If you need to enter your password, note that your keystrokes will not display in the Terminal window but they will be recorded. Simply press the return key once you’ve entered your password. Otherwise press the letter y for “yes” whenever you are prompted to confirm the installation.

      Let’s walk through the flags that are associated with the curl command:

      • The -f or --fail flag tells the Terminal window to give no HTML document output on server errors.
      • The -s or --silent flag mutes curl so that it does not show the progress meter, and combined with the -S or --show-error flag it will ensure that curl shows an error message if it fails.
      • The -L or --location flag will tell curl to redo the request to a new place if the server reports that the requested page has moved to a different location.

      Once the installation process is complete, we’ll put the Homebrew directory at the top of the PATH environment variable. This will ensure that Homebrew installations will be called over the tools that macOS may select automatically that could run counter to the development environment we’re creating.

      You should create or open the ~/.bash_profile file with the command-line text editor nano using the nano command:

      Once the file opens up in the Terminal window, write the following:

      export PATH=/usr/local/bin:$PATH
      

      To save your changes, hold down the CTRL key and the letter o, and when prompted press the RETURN key. Now you can exit nano by holding the CTRL key and the letter x.

      Activate these changes by executing the following in Terminal:

      Once you have done this, the changes you have made to the PATH environment variable will go into effect.

      You can make sure that Homebrew was successfully installed by typing:

      If no updates are required at this time, the Terminal output will read:

      Output

      Your system is ready to brew.

      Otherwise, you may get a warning to run another command such as brew update to ensure that your installation of Homebrew is up to date.

      Once Homebrew is ready, you can install Go.

      Step 4 — Installing Go

      You can use Homebrew to search for all available packages with the brew search command. For the purpose of this tutorial, you will search for Go-related packages or modules:

      Note: This tutorial does not use brew search go as it returns too many results. Because go is such a small word and would match many packages, it has become common to use golang as the search term. This is common practice when searching the internet for Go-related articles as well. The term Golang was born from the domain for Go, which is golang.org.

      The Terminal will output a list of what you can install:

      Output

      golang golang-migrate

      Go will be among the items on the list. Go ahead and install it:

      The Terminal window will give you feedback regarding the installation process of Go. It may take a few minutes before installation is complete.

      To check the version of Go that you installed, type the following:

      This will output the specific version of Go that is currently installed, which will by default be the most up-to-date, stable version of Go that is available.

      In the future, to update Go, you can run the following commands to first update Homebrew and then update Go. You don't have to do this now, as you just installed the latest version:

      • brew update
      • brew upgrade golang

      brew update will update the formulae for Homebrew itself, ensuring you have the latest information for packages you want to install. brew upgrade golang will update the golang package to the latest release of the package.

      It is good practice to ensure that your version of Go is up-to-date.

      With Go installed on your computer, you are now ready to create a workspace for your Go projects.

      Step 5 — Creating Your Go Workspace

      Now that you have Xcode, Homebrew, and Go installed, you can go on to create your programming workspace.

      The Go workspace will contain two directories at its root:

      • src: The directory that contains Go source files. A source file is a file that you write using the Go programming language. Source files are used by the Go compiler to create an executable binary file.
      • bin: The directory that contains executables built and installed by the Go tools. Executables are binary files that run on your system and execute tasks. These are typically the programs compiled by your source code or another downloaded Go source code.

      The src subdirectory may contain multiple version control repositories (such as Git, Mercurial, and Bazaar). You will see directories like github.com or golang.org when your program imports third party libraries. If you are using a code repository like github.com, you will also put your projects and source files under that directory. This allows for a canonical import of code in your project. Canonical imports are imports that reference a fully qualified package, such as github.com/digitalocean/godo.

      Here is what a typical workspace may look like:

      .
      ├── bin
      │   ├── buffalo                                      # command executable
      │   ├── dlv                                          # command executable
      │   └── packr                                        # command executable
      └── src
          └── github.com
              └── digitalocean
                  └── godo
                      ├── .git                            # Git reposistory metadata
                      ├── account.go                      # package source
                      ├── account_test.go                 # test source
                      ├── ...
                      ├── timestamp.go
                      ├── timestamp_test.go
                      └── util
                          ├── droplet.go
                          └── droplet_test.go
      

      The default directory for the Go workspace as of 1.8 is your user's home directory with a go subdirectory, or $HOME/go. If you are using a version of Go earlier than 1.8, it is considered best practice to still use the $HOME/go location for your workspace.

      Issue the following command to create the directory structure for your Go workspace:

      • mkdir -p $HOME/go/{bin,src}

      The -p option tells mkdir to create all parents in the directory, even if they don't currently exist. Using {bin,src} creates a set of arguments to mkdir and tells it to create both the bin directory and the src directory.

      This will ensure the following directory structure is now in place:

      └── $HOME
          └── go
              ├── bin
              └── src
      

      Prior to Go 1.8, it was required to set a local environment variable called $GOPATH. While it is no longer explicitly required to do so, it is still considered a good practice as many third party tools still depend on this variable being set.

      You can set your $GOPATH by adding it to your ~/.bash_profile.

      First, open ~/.bash_profile with nano or your preferred text editor:

      Set your $GOPATH by adding the following to the file:

      ~/.bash_profile

      export GOPATH=$HOME/go
      

      When Go compiles and installs tools, it will put them in the $GOPATH/bin directory. For convenience, it's common to add the workspace's /bin subdirectory to your PATH in your ~/.bash_profile:

      ~/.bash_profile

      export PATH=$PATH:$GOPATH/bin
      

      You should now have the following entries in your ~/.bash_profile:

      ~/.bash_profile

      export GOPATH=$HOME/go
      export PATH=$PATH:$GOPATH/bin
      

      This will now allow you to run any programs you compile or download via the Go tools anywhere on your system.

      To update your shell, issue the following command to load the global variables you just created:

      You can verify your $PATH is updated by using the echo command and inspecting the output:

      You should see your $GOPATH/bin which will show up in your home directory. If you were logged in as sammy, you would see /Users/sammy/go/bin in the path.

      Output

      /Users/sammy/go/bin:/usr/local/sbin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin

      Now that you have the root of the workspace created and your $GOPATH environment variable set, you will create your future projects with the following directory structure. This example assumes you are using github.com as your repository:

      $GOPATH/src/github.com/username/project
      

      If you were working on the https://github.com/digitalocean/godo project, you would put it in the following directory:

      $GOPATH/src/github.com/digitalocean/godo
      

      Structuring your projects in this manner will make projects available with the go get tool. It will also help readability later.

      You can verify this by using the go get command to fetch the godo library:

      • go get github.com/digitalocean/godo

      We can see it successfully download the godo package by listing the directory:

      • ls -l $GOPATH/src/github.com/digitalocean/godo

      You will receive output similar to this:

      Output

      -rw-r--r-- 1 sammy staff 2892 Apr 5 15:56 CHANGELOG.md -rw-r--r-- 1 sammy staff 1851 Apr 5 15:56 CONTRIBUTING.md . . . -rw-r--r-- 1 sammy staff 4893 Apr 5 15:56 vpcs.go -rw-r--r-- 1 sammy staff 4091 Apr 5 15:56 vpcs_test.go

      In this step, you created a Go workspace and configured the necessary environment variables. In the next step you will test the workspace with some code.

      Step 6 — Creating a Simple Program

      Now that you have your Go workspace set up, it's time to create a simple “Hello, World!” program. This will make sure that your workspace is working and gives you the opportunity to become more familiar with Go.

      Because you are creating a single Go source file, and not an actual project, you don't need to be in your workspace to do this.

      From your home directory, open up a command-line text editor, such as nano, and create a new file:

      Once the text file opens up in Terminal, type out your program:

      package main
      
      import "fmt"
      
      func main() {
          fmt.Println("Hello, World!")
      }
      

      Exit nano by typing the control and x keys, and when prompted to save the file press y.

      This code will use the fmt package and call the Println function with Hello, World! as the argument. This will cause the phrase Hello, World! to print out to the terminal when the program is run.

      Once you exit out of nano and return to your shell, run the program:

      The hello.go program that you just created will cause Terminal to produce the following output:

      Output

      Hello, World!

      In this step, you used a basic program to verify that your Go workspace is properly configured.

      Conclusion

      Congratulations! At this point you have a Go programming workspace set up on your local macOS machine and can begin a coding project!



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      How To Install Python 3 and Set Up a Programming Environment on Ubuntu 18.04 [Quickstart]


      Introduction

      Python is a flexible and versatile programming language, with strengths in scripting, automation, data analysis, machine learning, and back-end development.

      This tutorial will walk you through installing Python and setting up a programming environment on an Ubuntu 18.04 server. For a more detailed version of this tutorial, with better explanations of each step, please refer to How To Install Python 3 and Set Up a Programming Environment on an Ubuntu 18.04 Server.

      Step 1 — Update and Upgrade

      Logged into your Ubuntu 18.04 server as a sudo non-root user, first update and upgrade your system to ensure that your shipped version of Python 3 is up-to-date.

      • sudo apt update
      • sudo apt -y upgrade

      Confirm installation if prompted to do so.

      Step 2 — Check Version of Python

      Check which version of Python 3 is installed by typing:

      You’ll receive output similar to the following, depending on when you have updated your system.

      Output

      Python 3.6.5

      Step 3 — Install pip

      To manage software packages for Python, install pip, a tool that will install and manage libraries or modules to use in your projects.

      • sudo apt install -y python3-pip

      Python packages can be installed by typing:

      • pip3 install package_name

      Here, package_name can refer to any Python package or library, such as Django for web development or NumPy for scientific computing. So if you would like to install NumPy, you can do so with the command pip3 install numpy.

      There are a few more packages and development tools to install to ensure that we have a robust set-up for our programming environment:

      • sudo apt install build-essential libssl-dev libffi-dev python3-dev

      Step 5 — Install venv

      Virtual environments enable you to have an isolated space on your server for Python projects. We’ll use venv, part of the standard Python 3 library, which we can install by typing:

      • sudo apt install -y python3-venv

      Step 6 — Create a Virtual Environment

      You can create a new environment with the pyvenv command. Here, we’ll call our new environment my_env, but you can call yours whatever you want.

      Step 7 — Activate Virtual Environment

      Activate the environment using the command below, where my_env is the name of your programming environment.

      • source my_env/bin/activate

      Your command prompt will now be prefixed with the name of your environment:

      Step 8 — Test Virtual Environment

      Open the Python interpreter:

      Note that within the Python 3 virtual environment, you can use the command python instead of python3, and pip instead of pip3.

      You’ll know you’re in the interpreter when you receive the following output:

      Python 3.6.5 (default, Apr  1 2018, 05:46:30) 
      [GCC 7.3.0] on linux
      Type "help", "copyright", "credits" or "license" for more information.
      >>> 
      

      Now, use the print() function to create the traditional Hello, World program:

      Output

      Hello, World!

      Step 9 — Deactivate Virtual Environment

      Quit the Python interpreter:

      Then exit the virtual environment:

      Further Reading

      Here are links to more detailed tutorials that are related to this guide:



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      How To Install Python 3 and Set Up a Programming Environment on Debian 9


      Introduction

      A flexible and versatile programming language, Python is effective for many use cases, including scripting, automation, data analysis, machine learning, and back-end development. First published in 1991 with a name inspired by the British comedy group Monty Python, the development team wanted to make Python a language that was fun to use. Quick to set up, and written in a relatively straightforward style with immediate feedback on errors, Python is a great choice for beginners and experienced developers alike. Python 3 is the most current version of the language and is considered to be the future of Python.

      This tutorial will get your Debian 9 server set up with a Python 3 programming environment. Programming on a server has many advantages and supports collaboration across development projects.

      Prerequisites

      In order to complete this tutorial, you should have a non-root user with sudo privileges on a Debian 9 server. To learn how to achieve this setup, follow our Debian 9 initial server setup guide.

      If you’re not already familiar with a terminal environment, you may find the article “An Introduction to the Linux Terminal” useful for becoming better oriented with the terminal.

      With your server and user set up, you are ready to begin.

      Step 1 — Setting Up Python 3

      Debian Linux ships with both Python 3 and Python 2 pre-installed. To make sure that our versions are up-to-date, let’s update and upgrade the system with the apt command to work with the Advanced Packaging Tool:

      • sudo apt update
      • sudo apt -y upgrade

      The -y flag will confirm that we are agreeing for all items to be installed.

      Once the process is complete, we can check the version of Python 3 that is installed in the system by typing:

      You’ll receive output in the terminal window that will let you know the version number. While this number may vary, the output will be similar to this:

      Output

      Python 3.5.3

      To manage software packages for Python, let’s install pip, a tool that will install and manage programming packages we may want to use in our development projects. You can learn more about modules or packages that you can install with pip by reading “How To Import Modules in Python 3.”

      • sudo apt install -y python3-pip

      Python packages can be installed by typing:

      • pip3 install package_name

      Here, package_name can refer to any Python package or library, such as Django for web development or NumPy for scientific computing. So if you would like to install NumPy, you can do so with the command pip3 install numpy.

      There are a few more packages and development tools to install to ensure that we have a robust set-up for our programming environment:

      • sudo apt install build-essential libssl-dev libffi-dev python3-dev

      Once Python is set up, and pip and other tools are installed, we can set up a virtual environment for our development projects.

      Step 2 — Setting Up a Virtual Environment

      Virtual environments enable you to have an isolated space on your server for Python projects, ensuring that each of your projects can have its own set of dependencies that won’t disrupt any of your other projects.

      Setting up a programming environment provides us with greater control over our Python projects and over how different versions of packages are handled. This is especially important when working with third-party packages.

      You can set up as many Python programming environments as you want. Each environment is basically a directory or folder on your server that has a few scripts in it to make it act as an environment.

      While there are a few ways to achieve a programming environment in Python, we’ll be using the venv module here, which is part of the standard Python 3 library. Let’s install venv by typing:

      • sudo apt install -y python3-venv

      With this installed, we are ready to create environments. Let’s either choose which directory we would like to put our Python programming environments in, or create a new directory with mkdir, as in:

      • mkdir environments
      • cd environments

      Once you are in the directory where you would like the environments to live, you can create an environment by running the following command:

      Essentially, pyvenv sets up a new directory that contains a few items which we can view with the ls command:

      Output

      bin include lib lib64 pyvenv.cfg share

      Together, these files work to make sure that your projects are isolated from the broader context of your local machine, so that system files and project files don’t mix. This is good practice for version control and to ensure that each of your projects has access to the particular packages that it needs. Python Wheels, a built-package format for Python that can speed up your software production by reducing the number of times you need to compile, will be in the Ubuntu 18.04 share directory.

      To use this environment, you need to activate it, which you can achieve by typing the following command that calls the activate script:

      • source my_env/bin/activate

      Your command prompt will now be prefixed with the name of your environment, in this case it is called my_env. Depending on what version of Debian Linux you are running, your prefix may appear somewhat differently, but the name of your environment in parentheses should be the first thing you see on your line:

      This prefix lets us know that the environment my_env is currently active, meaning that when we create programs here they will use only this particular environment’s settings and packages.

      Note: Within the virtual environment, you can use the command python instead of python3, and pip instead of pip3 if you would prefer. If you use Python 3 on your machine outside of an environment, you will need to use the python3 and pip3 commands exclusively.

      After following these steps, your virtual environment is ready to use.

      Step 3 — Creating a “Hello, World” Program

      Now that we have our virtual environment set up, let’s create a traditional “Hello, World!” program. This will let us test our environment and provides us with the opportunity to become more familiar with Python if we aren’t already.

      To do this, we’ll open up a command-line text editor such as nano and create a new file:

      Once the text file opens up in the terminal window we’ll type out our program:

      print("Hello, World!")
      

      Exit nano by typing the CTRL and X keys, and when prompted to save the file press y.

      Once you exit out of nano and return to your shell, let’s run the program:

      The hello.py program that you just created should cause your terminal to produce the following output:

      Output

      Hello, World!

      To leave the environment, simply type the command deactivate and you will return to your original directory.

      Conclusion

      Congratulations! At this point you have a Python 3 programming environment set up on your Debian 9 Linux server and you can now begin a coding project!

      If you are using a local machine rather than a server, refer to the tutorial that is relevant to your operating system in our “How To Install and Set Up a Local Programming Environment for Python 3” series.

      With your server ready for software development, you can continue to learn more about coding in Python by reading our free How To Code in Python 3 eBook, or consulting our Programming Project tutorials.

      Download our free Python eBook!

      How To Code in Python eBook in EPUB format

      How To Code in Python eBook in PDF format



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