mcda-elicitation-web

This tool provides a web interface for Multiple Criteria Decision Analysis preference elicitation. Currently, it supports eliciting the following types of preference information:

• Linear partial value functions
• Piece-wise linear partial value functions using MACBETH
• Ranking criteria trade-offs (ordinal SWING)
• Exact criteria trade-off ratios (exact SWING)
• Imprecise criteria trade-off ratios (interval SWING)

The tool uses the Patavi web service wrapper for R and the 'hitandrun' and 'smaa' R packages to calculate MCDA results during and after the preference elicitation process.

mcda-elicitation-web is a component of the drugis.org ADDIS 2 project. For more information on all components of the drugis project, please refer to the OVERALL-README.md in the root folder of the ADDIS-CORE project.

Prerequisites for running mcda-web

• A PostgreSQL instance with an initialised database. See liquibase/process.md for information on how to initialize.

If you already have a postgresql database you can use, it can be initialised as follows (change passwords as desired):

CREATE USER mcda WITH PASSWORD 'develop';
CREATE DATABASE mcda ENCODING 'utf-8' OWNER mcda;

Create a .pgpass in the user home to store the database password the file should contain a line with the following format hostname:port:database:username:password, e.g:

localhost:5432:mcda:mcda:develop

Create the schema (shell script)

psql -h localhost -U mcda -d mcda -f database.pg.sql

• A patavi-server instance along with a rabbitMQ service. see the patavi repository for installation and running instructions.

• At least one smaa patavi worker, started by executing the run-worker.sh script.

Running as Docker container

Building the image (optional)

You can build a new local image by executing the build-docker.sh script.

The build-docker.sh script lets you specify the signin method via command line argument. The current options are Google OAuth 2.0 (GOOGLE) and username/password (LOCAL). The default signin method is Google OAuth 2.0.

For local signin, there are several further dependencies (assuming a version of NodeJS of 10.x) to generate the users and passwords:

sudo npm -g install yarn
sudo npm -g install npx
yarn

After installing these dependencies, you can add users for the LOCAL signin method by using the add-user.sh script.

Running the container

Execute the run-mcda-docker.sh script.

If you built the container with a specific login method arugment, you should run the run-mcda-docker.sh script with the same one.

e.g.:

./build-docker.sh LOCAL
./run-mcda-docker.sh LOCAL

Note that you should probably change the default settings in the script (e.g. check whether the link arguments match the names of your containers, and whether the Patavi API key is correct). The script also assumes that the sql database and patavi server and worker are already set up and running. The run script runs the addis/mcda image, which will be pulled from docker hub by default.

Running as standalone application

Setting up the database

sudo -u postgres psql -c "CREATE USER mcda WITH PASSWORD 'develop'" sudo -u postgres psql -c "CREATE DATABASE mcda ENCODING 'utf-8' OWNER mcda" psql -d mcda -U mcda -f database.pg.sql

Running

Set environment variables:

export MCDAWEB_DB_USER=mcdaweb
export MCDAWEB_DB_PASSWORD=develop
export MCDAWEB_DB_HOST=localhost
export MCDAWEB_DB_NAME=mcda
export MCDAWEB_GOOGLE_KEY=<something>
export MCDAWEB_GOOGLE_SECRET=<something-else>
export MCDAWEB_COOKIE_SECRET=<some-random-string>
export MCDA_HOST=localhost
export PATAVI_HOST=localhost
export PATAVI_PORT=3000
export PATAVI_API_KEY=somekeyvalue
export SECURE_TRAFFIC=false

Getting the dependencies:

yarn

Building the backend application (Warning: this command also deletes the frontend build artefacts):

yarn build-backend

Building the frontend application:

yarn build-prod

Running the application:

node index.js or npm start

Running the patavi worker

As a prerequisite, build the patavi worker image from the patavi repository.

Then, build the worker itself, in the R directory:

docker build --tag patavi/worker-smaa_v2 .

Run the worker:

docker run -d --link <rabbitmq-container-name>:rabbit --name patavi-smaa_v2 patavi/worker-smaa_v2

Development

Tests

Executing tests (front-end unit tests, back-end, and R unit tests):

npm test

Executing end-to-end tests:

yarn test-end-to-end

Requirements for end-to-end tests:

• a local login build
• a test user with credentials user/password
• a running server (on http://localhost:3002, can be changed in test/endToEnd/util/constants.js'http://localhost:3002')
• a Firefox browser (tested on 69.0.2)

Building the frontend with inline source maps for faster debugging:

yarn build-dev

Continually rebuilding while you develop:

yarn dev

Building a local login version:

yarn build-local-login

Initialize submodules (only needed for CSS rebuilding)

git submodule init
git submodule update

Compiling the CSS

Using compass (through config.rb):

compass compile

Using node-sass:

node-sass --include-path sass-shared sass/mcda-plain.scss app/css/mcda-plain.css
node-sass --include-path sass-shared sass/mcda-drugis.scss app/css/mcda-drugis.css

License

mcda-elicitation-web is open source, and licensed under GPLv3. See LICENSE.txt for more information.