/aws-elastic-beanstalk-cli-setup

Simplified EB CLI installation mechanism.

Primary LanguagePythonMozilla Public License 2.0MPL-2.0

EB CLI Installer


1. Overview


This repository hosts scripts to generate self-contained installations of the EB CLI.


1.1. Prerequisites

If you don't have Git, install it from Git Downloads.

Python, which the EBCLI Installer depends on, requires the following prerequisites for each operating system.

  • Linux

    • Ubuntu and Debian

      build-essential zlib1g-dev libssl-dev libncurses-dev libffi-dev libsqlite3-dev libreadline-dev libbz2-dev
    • Amazon Linux and Fedora

      "Development Tools" zlib-devel openssl-devel ncurses-devel libffi-devel sqlite-devel.x86_64 readline-devel.x86_64 bzip2-devel.x86_64
  • macOS

    openssl zlib readline

2. Use


2.1. Clone this repository

Use the following:

git clone https://github.com/aws/aws-elastic-beanstalk-cli-setup.git

2.2. Install/Upgrade the EB CLI

On Bash and Zsh on macOS and Linux:

./aws-elastic-beanstalk-cli-setup/scripts/bundled_installer

In PowerShell or in a Command Prompt window:

.\aws-elastic-beanstalk-cli-setup\scripts\bundled_installer

2.3. Troubleshooting

  • Linux

    Most installation problems have been due to missing libraries such as OpenSSL.

    • On Ubuntu and Debian, run the following command to install dependencies.

      apt-get install \
          build-essential zlib1g-dev libssl-dev libncurses-dev \
          libffi-dev libsqlite3-dev libreadline-dev libbz2-dev
    • On Amazon Linux and Fedora, run the following command to install dependencies.

      yum group install "Development Tools"
      yum install \
          zlib-devel openssl-devel ncurses-devel libffi-devel \
          sqlite-devel.x86_64 readline-devel.x86_64 bzip2-devel.x86_64
  • macOS

    Most installation problems on macOS are related to loading and linking OpenSSL and zlib. The following command installs the necessary packages and tells the Python installer where to find them:

    brew install zlib openssl readline
    CFLAGS="-I$(brew --prefix openssl)/include -I$(brew --prefix readline)/include -I$(xcrun --show-sdk-path)/usr/include" LDFLAGS="-L$(brew --prefix openssl)/lib -L$(brew --prefix readline)/lib -L$(brew --prefix zlib)/lib"
    
  • Windows

    • In PowerShell, if you encounter an error with the message "execution of scripts is disabled on this system", set the execution policy to "RemoteSigned" and then rerun bundled_installer.

      Set-ExecutionPolicy RemoteSigned
    • If you encounter an error with the message "No module named 'virtualenv'", use the following commands to install virtualenv and the EB CLI:

      pip uninstall -y virtualenv
      pip install virtualenv
      python .\aws-elastic-beanstalk-cli-setup\scripts\ebcli_installer.py

2.4. After installation

On Linux and macOS, the output contains instructions to add the EB CLI (and Python) executable file to the shell's $PATH variable, if it isn't already in it.

2.5. Demo execution of bundled_installer

Demo

3. Advanced use

To install the EB CLI, bundled_installer runs ebcli_installer.py. ebcli_installer.py has the following capabilities:

  • To install a specific version of the EB CLI:

    python scripts/ebcli_installer.py --version 3.14.13
  • To install the EB CLI with a specific version of Python (the Python version doesn't need to be in $PATH):

    python scripts/ebcli_installer.py --python-installation /path/to/some/python/on/your/computer
  • To install the EB CLI from source (Git repository, .tar file, .zip file):

    python scripts/ebcli_installer.py --ebcli-source /path/to/awsebcli.zip
    
    python scripts/ebcli_installer.py --ebcli-source /path/to/EBCLI/codebase/on/your/computer
  • To install the EB CLI at a specific location, instead of in the standard .ebcli-virtual-env directory in the user's home directory:

    python scripts/ebcli_installer.py --location /path/to/ebcli/installation/location

Run the following command to view the help text for ebcli_installer.py:

python scripts/ebcli_installer.py --help

4. Frequently asked questions


4.1. Can I skip the Python installation?

Yes. If you already have Python installed on your system, after step 2.1., run the following.

On Bash and Zsh:

python aws-elastic-beanstalk-cli-setup/scripts/ebcli_installer.py

In PowerShell and from the Command Prompt window:

python .\aws-elastic-beanstalk-cli-setup\scripts\ebcli_installer.py

4.2. For the experienced Python developer, what's the advantage of this mode of installation instead of regular pip inside a virtualenv?

Even within a virtualenv, a developer might need to install multiple packages whose dependencies are in conflict. For example, at times the AWS CLI and the EB CLI have used conflicting versions of botocore. One such instance was particularly egregious. When there are conflicts, users have to manage separate virtualenvs for each of the conflicting packages, or find a combination of the packages without conflicts. Both these workarounds become unmanageable over time, and as the number of packages that are in conflict increases.

4.3. On macOS (or Linux systems with brew), is this better than brew install awsebcli?

Yes, for these reasons:

  • The AWS Elastic Beanstalk team has no control over how brew operates.
  • The brew install ... mechanism doesn't solve the problem of dependency conflicts, which is a primary goal of this project.

4.3. For developers who are new to Python, does this mode of installation pose challenges?

The opinion of the AWS Elastic Beanstalk team is "No".

Aside from the problem described in 4.2., developers new to Python are often confused by the presence of multiple versions of Python and pip executable files on their system. A common problem that such developers encounter is that when they install eb with one pip executable file (presumably using the sudo prefix), no eb-related commands work because the correct set of directories isn't referenced correctly.

Typically, for such developers, use of virtualenv is the correct path forward. However, this becomes yet another hurdle before using eb.

Another common problem is where users install Python and pip in ways that Elastic Beanstalk Documentation doesn't recommend, such as using arbitrary Personal Package Archives (PPAs) on Ubuntu, or similar unmaintained sources that lack scrutiny.

4.4. Can I execute the Bash scripts in a Cygwin, git-bash, or other Bash-like shell on Windows?

No. At this time, we don't directly support execution on Bash-like environments on Windows. Use PowerShell or the Command Prompt window to install. You can add the location of the eb and Python executable files to $PATH .

4.5. Can I execute the Bash scripts in a fish shell?

Yes, but only if you have Bash on your computer. At this time we don't provide specific guidance on how to set $PATH in Fish, however, Fish has detailed documentation for this purpose.

4.6. I already have Python installed. Can I still execute bundled_installer?

Yes. It's safe to execute bundled_installer even if you already have Python installed. The installer will skip reinstallation.

4.7. I already have the EB CLI installed. Can I still execute ebcli_installer.py?

Yes.

Consider the following two cases:

  • ebcli_installer.py was previously run, creating .ebcli-virtual-env in the user's home directory (or the user's choice of a directory indicated through the --location argument). In this case, the EB CLI will overwrite .ebcli-virtual-env and attempt to install the latest version of the EB CLI in the virtualenv within it.

  • eb is in $PATH, however, it wasn't installed by ebcli_installer.py. In this case, the installer will install eb within .ebcli-virtual-env in the user's home directory (or the user's choice of a directory indicated through the --location argument), and prompt the user to prefix /path-to/.ebcli-virtual-env/executables to $PATH. Until you perform this action, the older eb executable file will continue to be referenced when you type eb.

4.8. How does ebcli_installer.py work?

When executing the Python script, ebcli_installer.py does the following:

  • Creates a virtualenv exclusive to the eb installation.
  • Installs eb inside that virtualenv.
  • In the <installation-location>/executables directory, it generates:
    • A .py wrapper for eb on Linux or macOS.
    • .bat and .ps1 wrappers for eb on Windows.
  • When complete, you will be prompted to add <installation-location>/executables to $PATH, only if the directory is not already in it.

4.8. How does bundled_installer work?

  • On macOS or Linux, bundled_installer uses the extremely popular pyenv project to install the latest version of Python 3.7.
  • On Windows, it downloads the MSI installer of the latest Python version from Python's website and silently installs it.

4.9. Are there dependency problems that this mode of installation doesn't solve?

Unfortunately, yes.

Suppose the dependencies of eb, say Dep A and Dep B, are in conflict. Because pip lacks dependency management capabilities, the resulting eb installation might not work.

4.10. Is it okay to use Python 2.7 to install the EB CLI?

Yes, however, be aware that Python 2.7 will be deprecated on January 1, 2020. There won't be security updates after that date.

Also, the latest minor version series, Python 3.7, offers significant improvements over the Python 2.7 series. We highly recommend that you use Python 3.7 for testing purposes, even though the Elastic Beanstalk team tests the EB CLI against Python 2.7.

5. License

This library is licensed under the Mozilla Public License Version 2.0.