# Installation
* Table of Contents
{:toc}

## Overview
CORE provides a script to help automate the installation of dependencies,
build and install, and either generate a CORE specific python virtual environment
or build and install a python wheel.

> **WARNING:** if Docker is installed, the default iptable rules will block CORE traffic

### Requirements
Any computer capable of running Linux should be able to run CORE. Since the physical machine will be hosting numerous
containers, as a general rule you should select a machine having as much RAM and CPU resources as possible.

* Linux Kernel v3.3+
* iproute2 4.5+ is a requirement for bridge related commands
* nftables compatible kernel and nft command line tool

### Supported Linux Distributions
Plan is to support recent Ubuntu and CentOS LTS releases.

Verified:
* Ubuntu - 18.04, 20.04
* CentOS - 7.8, 8.0

> **NOTE:** CentOS 8 does not have the netem kernel mod available by default

CentOS 8 Enabled netem:
```shell
sudo yum update
# restart into updated kernel
sudo yum install -y kernel-modules-extra
sudo modprobe sch_netem
```

### Tools Used
The following tools will be leveraged during installation:

| Tool                                        | Description                                                           |
|---------------------------------------------|-----------------------------------------------------------------------|
| [pip](https://pip.pypa.io/en/stable/)       | used to install pipx                                                  |
| [pipx](https://pipxproject.github.io/pipx/) | used to install standalone python tools (invoke, poetry)              |
| [invoke](http://www.pyinvoke.org/)          | used to run provided tasks (install, uninstall, reinstall, etc)       |
| [poetry](https://python-poetry.org/)        | used to install python virtual environment or building a python wheel |

### Files
The following is a list of files that would be installed after running the automated installation.

> **NOTE:** the default install prefix is /usr/local, but can be changed as noted below

* executable files
  * `<prefix>/bin/{core-daemon, core-gui, vcmd, vnoded, etc}`
* python files
  * poetry virtual env
    * `cd <repo>/daemon && poetry env info`
    * `~/.cache/pypoetry/virtualenvs/`
  * local python install
    * default install path for python3 installation of a wheel
    * `python3 -c "import core; print(core.__file__)"`
* configuration files
  * `/etc/core/{core.conf, logging.conf}`
* ospf mdr repository files
  * `<repo>/../ospf-mdr`
* emane repository files
  * `<repo>/../emane`

### Installed Executables
After the installation complete it will have installed the following scripts.

| Name                | Description                                                                  |
|---------------------|------------------------------------------------------------------------------|
| core-cleanup        | tool to help removed lingering core created containers, bridges, directories |
| core-cli            | tool to query, open xml files, and send commands using gRPC                  |
| core-daemon         | runs the backed core server providing a gRPC API                             |
| core-gui            | starts GUI                                                                   |
| core-python         | provides a convenience for running the core python virtual environment       |
| core-route-monitor  | tool to help monitor traffic across nodes and feed that to SDT               |
| core-service-update | tool to update automate modifying a legacy service to match current naming   |

## Upgrading from Older Release
Please make sure to uninstall any previous installations of CORE cleanly
before proceeding to install.

Clearing out a current install from 7.0.0+, making sure to provide options
used for install (`-l` or `-p`).
```shell
cd <CORE_REPO>
inv uninstall <options>
```

Previous install was built from source for CORE release older than 7.0.0:
```shell
cd <CORE_REPO>
sudo make uninstall
make clean
./bootstrap.sh clean
```

Installed from previously built packages:
```shell
# centos
sudo yum remove core
# ubuntu
sudo apt remove core
```

## Automated Install
First we will need to clone and navigate to the CORE repo.
```shell
# clone CORE repo
git clone https://github.com/coreemu/core.git
cd core
# install dependencies to run installation task
./setup.sh
# run the following or open a new terminal
source ~/.bashrc
# Ubuntu
inv install
# CentOS
inv install -p /usr
```

First you can use `setup.sh` as a convenience to install tooling for running invoke tasks:

> **NOTE:** `setup.sh` will attempt to determine your OS by way of `/etc/os-release`, currently it supports
> attempts to install OSs that are debian/redhat like (yum/apt).

* python3, pip, venv
* pipx 0.16.4 via pip
* invoke 1.4.1 via pipx
* poetry 1.1.12 via pipx

Then you can run `inv install <options>`:
* installs system dependencies for building core
* installs core into poetry managed virtual environment or locally, if flag is passed
* installs scripts pointing to appropriate python location based on install type
* installs systemd service pointing to appropriate python location based on install type
* clone/build/install working version of [OPSF MDR](https://github.com/USNavalResearchLaboratory/ospf-mdr)

> **NOTE:** installing locally comes with its own risks, it can result it potential
> dependency conflicts with system package manager installed python dependencies

> **NOTE:** provide a prefix that will be found on path when running as sudo,
> if the default prefix /usr/local will not be valid

```shell
inv -h install

Usage: inv[oke] [--core-opts] install [--options] [other tasks here ...]

Docstring:
  install core, poetry, scripts, service, and ospf mdr

Options:
  -d, --dev                          install development mode
  -i STRING, --install-type=STRING   used to force an install type, can be one of the following (redhat, debian)
  -l, --local                        determines if core will install to local system, default is False
  -o, --[no-]ospf                    disable ospf installation
  -p STRING, --prefix=STRING         prefix where scripts are installed, default is /usr/local
  -v, --verbose                      enable verbose

# install core to virtual environment
./install.sh -p <prefix>

# install core locally
./install.sh -p <prefix> -l
```

After installation has completed you should be able to run `core-daemon` and `core-gui`.

## Using Invoke Tasks
The invoke tool installed by way of pipx provides conveniences for running
CORE tasks to help ensure usage of the create python virtual environment.

```shell
inv --list

Available tasks:

  install         install core, poetry, scripts, service, and ospf mdr
  install-emane   install emane python bindings into the core virtual environment
  reinstall       run the uninstall task, get latest from specified branch, and run install task
  test            run core tests
  test-emane      run core emane tests
  test-mock       run core tests using mock to avoid running as sudo
  uninstall       uninstall core, scripts, service, virtual environment, and clean build directory
```

### Enabling Service
After installation, the core service is not enabled by default. If you desire to use the
service, run the following commands.

```shell
sudo systemctl enable core-daemon
sudo systemctl start core-daemon
```

### Unsupported Linux Distribution
For unsupported OSs you could attempt to do the following to translate
an installation to your use case.

* make sure you have python3.6+ with venv support
* make sure you have python3 invoke available to leverage `<repo>/tasks.py`

```shell
# this will print the commands that would be ran for a given installation
# type without actually running them, they may help in being used as
# the basis for translating to your OS
inv install --dry -v -p <prefix> -i <install type>
```

## Dockerfile Install
You can leverage the provided Dockerfile, to run and launch CORE within a Docker container.

```shell
# clone core
git clone https://github.com/coreemu/core.git
cd core
# build image
sudo docker build -t core .
# start container
sudo docker run -itd --name core -e DISPLAY -v /tmp/.X11-unix:/tmp/.X11-unix:rw --privileged core
# enable xhost access to the root user
xhost +local:root
# launch core-gui
sudo docker exec -it core core-gui
```

## Running User Scripts
If you create your own python scripts to run CORE directly or using the gRPC
APIs you will need to make sure you are running them within context of the
installed virtual environment. To help support this CORE provides the `core-python`
executable. This executable will allow you to enter CORE's python virtual
environment interpreter or to run a script within it.

For installations installed to a virtual environment:
```shell
core-python <script>
```

For local installations:
```shell
python3 <script>
```

## Installing EMANE
> **NOTE:** installng emane for the virtual environment is known to work for 1.21+

The recommended way to install EMANE is using prebuilt packages, otherwise
you can follow their instructions for installing from source. Installation
information can be found [here](https://github.com/adjacentlink/emane/wiki/Install).

There is an invoke task to help install the EMANE bindings into the CORE virtual
environment, when needed.
```shell
cd <CORE_REPO>
inv install-emane
```
