# Setting up a local development environment

This document is intended to guide you through setting up a local development environment for Colouring London. This guide assumes you already have Ubuntu 18.04 or 20.04 server installed, typically installed in a virtual environment such a VirtualBox and are able to SSH into your Ubuntu installation for convenience.

<details>
<summary>
Configuring an Ubuntu VM in VirtualBox
</summary>

When setting up the VirtualBox VM, consider the size of the database you intend to load for use with the application. Consult the [loading the data](#loading-the-data) section of this guide and decide whether you will be using a full city database or will load test data from OSM.

For "Colouring London", we have found that the size of the database means that a VM with access to 50GB of storage is appropriate. If you are using the OSM test data, the default storage settings in VirtualBox should suffice.

##### In either case, you should set the memory to `2048` MB.

If you a running Ubuntu in a virtual environment you will need to configure networking to forward ports from the guest to the host. For Virtual Box the following was configured under NAT port forwarding (found under `Settings -> Network -> Advanced -> Port Forwarding`).

Name     | Protocol  | Host Port  | Guest Port
-------- | --------- | ---------- | -----------
app      | TCP       | 8080       | 3000
app_dev  | TCP       | 3001       | 3001
ssh      | TCP       | 4022       | 22

To run the commands in the rest of this setup guide, either `ssh` into the VirtualBox environment or open the terminal within the Ubuntu GUI.

If you wish to `ssh`, you will first need to open the terminal in Ubuntu and run the following.

```bash
sudo apt-get install -y openssh-server
```

You can then `ssh` into the VirtualBox VM set up with the port  forwarding described above like so, where `<linuxusername>` is the name you set up during the installation of Ubuntu (you can type `whoami` in the Ubuntu terminal to remind yourself of this).

```bash
ssh <linuxusername>@localhost -p 4022
```
</details>

## Installing the tools and components

First upgrade the installed packages to the latest versions, to remove any security warnings.

```bash
sudo apt-get update -y
sudo apt-get upgrade -y
```

Now we install some essential tools.

```bash
sudo apt-get install -y build-essential git vim-nox wget curl
```

Set the postgres repo for apt.

```bash
sudo sh -c 'echo "deb http://apt.postgresql.org/pub/repos/apt $(lsb_release -cs)-pgdg main" > /etc/apt/sources.list.d/pgdg.list'
```

```bash
sudo wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc | sudo apt-key add -
sudo apt-get update
```

Next install postgres and postgis to enable support for geographical objects.

```bash
sudo apt-get install -y postgresql postgresql-contrib libpq-dev postgis postgresql-14-postgis-3
```

and additional geo-spatial tools

```bash
sudo apt-get install -y gdal-bin libspatialindex-dev libgeos-dev libproj-dev
```

Now clone the colouring london codebase.

```bash
git clone https://github.com/colouring-london/colouring-london.git
```

Now install Node. It is helpful to define some local variables.

```bash
export NODE_VERSION=v16.13.2
export DISTRO=linux-x64
wget -nc https://nodejs.org/dist/$NODE_VERSION/node-$NODE_VERSION-$DISTRO.tar.xz
sudo mkdir /usr/local/lib/node
sudo tar xf node-$NODE_VERSION-$DISTRO.tar.xz -C /usr/local/lib/node
sudo mv /usr/local/lib/node/node-$NODE_VERSION-$DISTRO /usr/local/lib/node/node-$NODE_VERSION
rm node-$NODE_VERSION-$DISTRO.tar.xz
```

Now add the Node installation to the path and export this to your bash profile.

```bash
cat >> ~/.profile <<EOF
export NODEJS_HOME=/usr/local/lib/node/node-$NODE_VERSION/bin
export PATH=\$NODEJS_HOME:\$PATH
EOF
```

Then run source to make sure node and npm are on your path:

```bash
source ~/.profile
```

You can check the updated variables as follows

```bash
echo $PATH
echo $NODEJS_HOME
```

## Configuring Postgres

Now we configure postgres. First ensure postgres is running.

```bash
service postgresql start
```

Ensure the `en_US` locale exists.

```bash
sudo locale-gen en_US.UTF-8
```

Configure the database to listen on network connection.

```bash
sudo sed -i "s/#\?listen_address.*/listen_addresses '*'/" /etc/postgresql/14/main/postgresql.conf
```

Allow authenticated connections from any IP (so includes the host).

```bash
echo "host    all             all             all                     md5" | sudo tee --append /etc/postgresql/14/main/pg_hba.conf > /dev/null
```

Restart postgres to pick up config changes.

```bash
service postgresql restart
```

Create a superuser role for this user (`<username>`) if it does not already exist. The
password `<pgpassword>` is arbitrary and probably should not be your Ubuntu login password.

```bash
sudo -u postgres psql -c "SELECT 1 FROM pg_user WHERE usename = '<username>';" | grep -q 1 || sudo -u postgres psql -c "CREATE ROLE <username> SUPERUSER LOGIN PASSWORD '<pgpassword>';"
```

Set the `<pgpassword>` as an environment variable.

```bash
export PGPASSWORD=<pgpassword>
```

Create a colouring london database if none exists. The name (`<colouringlondondb>`) is arbitrary.

```bash
sudo -u postgres psql -c "SELECT 1 FROM pg_database WHERE datname = '<colouringlondondb>';" | grep -q 1 || sudo -u postgres createdb -E UTF8 -T template0 --locale=en_US.utf8 -O <username> <colouringlondondb>
```

Run `psql` interactively.

```bash
psql -d <colouringlondondb> -U <username> -h localhost
```

In `psql`, necessary postgres extensions.

```bash
create extension postgis;
create extension pgcrypto;
create extension pg_trgm;
```

Then quit `psql` by typing `\q` and hitting return.

Now run all 'up' migrations to create tables, data types, indexes etc. The `.sql` scripts to
do this are located in the `migrations` folder of your local repository.

```bash
ls ./colouring-london/migrations/*.up.sql 2>/dev/null | while read -r migration; do psql -d <colouringlondondb> -U <username> -h localhost < $migration; done;
```

## Setting up Node

Now upgrade the npm package manager to the most recent release with global privileges. This
needs to be performed as root user, so it is necessary to export the node variables to the
root user profile. Don't forget to exit from root at the end.

```bash
sudo su root
export NODEJS_HOME=/usr/local/lib/node/node-v16.13.2/bin/
export PATH=$NODEJS_HOME:$PATH
npm install -g npm@latest
exit
```

Now install the required Node packages. This needs to done from the `app` directory of your
local repository, so that it can read from the `package.json` file.

```bash
cd ./colouring-london/app
npm install
```

## Loading the data

<details>
<summary> With a database dump </summary>

If you are a developer on the Colouring London project (or another Colouring Cities project), you may have a production database (or staging etc) that you wish to duplicate in your development environment.

Log into the environment where your production database is kept and create a dump file from the db.

```bash
pg_dump <colouringlondondb> > <dumpfile>
```

You should then download the file to the machine where you are setting up your development environment. If you are using Virtualbox, you could host share the dump file with the VM via a shared folder (e.g. [see these instructions for Mac](https://medium.com/macoclock/share-folder-between-macos-and-ubuntu-4ce84fb5c1ad)).

In your Ubuntu installation where you have been running these setup steps (e.g. Virtualbox VM), you can then recrate the db like so.

```bash
psql -d <colouringlondondb> -U <username> -h localhost < <dumpfile>
```

</details>

<details>
<summary> With test data </summary>

Run the following two sections if you wish to load test buildings into the application from OpenStreetMaps (OSM).

#### Set up Python:

Install python and related tools.

```bash
sudo apt-get install -y python3 python3-pip python3-dev python3-venv
```

Now set up a virtual environment for python. In the following example we have named the
virtual environment *colouringlondon* but it can have any name.

```bash
pyvenv colouringlondon
```

Activate the virtual environment so we can install python packages into it.

```bash
source colouringlondon/bin/activate
```

Install python pip package manager and related tools.

```bash
pip install --upgrade pip
pip install --upgrade setuptools wheel
```

#### Load OpenStreetMap test polygons:

First install prerequisites.
```bash
sudo apt-get install parallel
```

Install the required python packages. This relies on the `requirements.txt` file located
in the `etl` folder of your local repository.

```bash
cd ~/colouring-london/etl/
pip install -r requirements.txt
```

To help test the Colouring London application, `get_test_polygons.py` will attempt to save a small (1.5km²) extract from OpenStreetMap to a format suitable for loading to the database.

First open `colouring-london/etl/load_geometries.sh` and `colouring-london/etl/create_building_records.sh` and add this `-d` flag to all the `psql` statements present (two in the former, one in the latter):

```bash
-d <colouringlondondb> -U <username> -h localhost
```

Then run:

```bash
# download test data
python get_test_polygons.py
```

Note: the first time you run it, you will get these warnings:
```
rm: cannot remove 'test_buildings.geojson': No such file or directory
rm: cannot remove 'test_buildings.3857.csv': No such file or directory
```

```bash
# load all building outlines
./load_geometries.sh ./
# index geometries (should be faster after loading)
psql -U <username> -h localhost -d <colouringlondondb> < ../migrations/002.index-geometries.up.sql
# create a building record per outline
./create_building_records.sh
# index building records
psql -U <username> -h localhost -d <colouringlondondb> < ../migrations/003.index-buildings.up.sql
```

#### Re-run database migrations

Re-run the remaining migrations in `../migrations` to create the rest of the database structure.

```bash
ls ./colouring-london/migrations/*.up.sql 2>/dev/null | while read -r migration; do psql -d <colouringlondondb> < $migration; done;
```
</details>

## Running the application

Now we are ready to run the application. The `APP_COOKIE_SECRET` is arbitrary.

First enter the app directory.

```bash
cd ~/colouring-london/app
```

Then create a folder for the tilecache.

```bash
mkdir tilecache
```

Finally, run the application.

```bash
PGPASSWORD=<pgpassword> PGDATABASE=<colouringlondondb> PGUSER=<username> PGHOST=localhost PGPORT=5432 APP_COOKIE_SECRET=123456 TILECACHE_PATH=~/colouring-london/app/tilecache npm start
```

The site can then be viewed on http://localhost:8080. The `app_dev` mapping is used in
development by Razzle which rebuilds and serves client side assets on the fly.

Finally to quit the application type `Ctrl-C`.