Elastic Beanstalk CLI Installer

1. Overview
- 1.1. Prerequisites
2. Quick start
3. Usage
- 3.1 Advanced usage
- 3.2 Options
4. Troubleshooting
5. Frequently asked questions
6. License

1. Overview

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

1.1. Prerequisites

You will need to have the following prerequisites installed before running the install script.

Git
- If not already installed you can download git from the Git downloads page.
Python
- We recommend that you install Python using the pyenv Python version manager. Alternately, you can download Python from the Python downloads page.
virtualenv
- Follow the virtualenv documentation to install virtualenv.

2. Quick start

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

MacOS/Linux

On Bash or Zsh:

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

Windows

In PowerShell or in a Command Prompt window:

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

2.3. 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.

3. Usage

The ebcli_installer.py Python script will install the awsebcli package in a virtual environment to prevent potential conflicts with other Python packages.

For most use cases you can execute the ebcli_installer.py script with no arguments.

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

3.1 Advanced usage

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
```
3.2 Options

options:
  -h, --help            show this help message and exit
  -e VIRTUALENV_EXECUTABLE, --virtualenv-executable VIRTUALENV_EXECUTABLE
                        path to the virtualenv installation to use to create the EBCLI's virtualenv
  -i, --hide-export-recommendation
                        boolean to hide recommendation to modify PATH
  -l LOCATION, --location LOCATION
                        location to store the awsebcli packages and its dependencies in
  -p PYTHON_INSTALLATION, --python-installation PYTHON_INSTALLATION
                        path to the python installation under which to install the awsebcli and its
                        dependencies
  -q, --quiet           enable quiet mode to display only minimal, necessary output
  -s EBCLI_SOURCE, --ebcli-source EBCLI_SOURCE
                        filesystem path to a Git repository of the EBCLI, or a .zip or .tar file of
                        the EBCLI source code; useful when testing a development version of the EBCLI.
  -v VERSION, --version VERSION
                        version of EBCLI to install

4. 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"
```
Run brew info to get the latest environment variable export suggestions, such as brew info zlib
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
```
  5. Frequently asked questions

5.1. 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 of these workarounds become unmanageable over time, and as the number of packages that are in conflict increases.

5.2. 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.

5.3. 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.

5.4. 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.

5.5. 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.

6. License

This library is licensed under the Apache-2.0 License.