pyceo/README.md

# pyceo
[![Build Status](https://ci.csclub.uwaterloo.ca/api/badges/public/pyceo/status.svg)](https://ci.csclub.uwaterloo.ca/public/pyceo)

![Main TUI view](https://wiki.csclub.uwaterloo.ca/images/b/bb/Pyceo.png)

CEO (**C**SC **E**lectronic **O**ffice) is the tool used by CSC to manage
club accounts and memberships. See [docs/architecture.md](docs/architecture.md) for an
overview of its architecture.

The API documentation is available as a plain HTML file in [docs/redoc-static.html](docs/redoc-static.html).

## Development
### Podman
If you are not modifying code related to email or Mailman, then you may use
Podman containers instead, which are much easier to work with than the VM.

If you are using Podman, make sure to set the `DOCKER_HOST` environment variable
if you have not done so already:
```bash
# Add the following to e.g. your ~/.bashrc
export DOCKER_HOST=unix://$XDG_RUNTIME_DIR/podman/podman.sock
```
The Podman socket also needs to be running:
```bash
# Enabled by default on Debian, but not on Fedora
systemctl --user enable --now podman.socket
```

First, create the container images:
```sh
scripts/build-all-images.sh
```
Then bring up the containers:
```sh
docker-compose up -d
```
This will create some containers with the bare minimum necessary for ceod to
run, and start ceod on each of phosphoric-acid, mail, and coffee container.
You can check the containers status using:
```sh
docker-compose logs -f
```

To use ceo, run the following:
```sh
docker-compose exec phosphoric-acid bash
su ctdalek
. venv/bin/activate
python -m ceo  # the password is krb5
```
This should bring up the TUI.

Normally, ceod should autoamtically restart when the source files are changed.
To manually restart the service, run:
```sh
docker-compose kill -s SIGHUP phosphoric-acid
```

To stop the containers, run:
```sh
docker-compose down
```
Alternatively, if you started docker-compose in the foreground, just press Ctrl-C.

### VM
If you need the full environment running in VM, follow the guide on
[syscom dev environment](https://git.uwaterloo.ca/csc/syscom-dev-environment).
This will setup all of the services needed for ceo to work. You should clone
this repo in the phosphoric-acid container under ctdalek's home directory; you
will then be able to access it from any container thanks to NFS.

Once you have the dev environment setup, there are a few more steps you'll
need to do for ceo.

#### Kerberos principals
First, you'll need `ceod/<hostname>` principals for each of phosphoric-acid,
coffee and mail. (coffee is taking over the role of caffeine for the DB
endpoints). For example, in the phosphoric-acid container:
```sh
kadmin -p sysadmin/admin
<password is krb5>
addprinc -randkey ceod/phosphoric-acid.csclub.internal
ktadd ceod/phosphoric-acid.csclub.internal
```
Do this for coffee and mail as well. You need to actually be in the
appropriate container when running these commands, since the credentials
are being added to the local keytab.
On phosphoric-acid, you will additionally need to create a principal
called `ceod/admin` (remember to addprinc **and** ktadd).

#### Database
**Note**: The instructions below apply to the dev environment only; in
production, the DB superusers should be restricted to the host where
the DB is running.

Attach to the coffee container, run `mysql`, and run the following:

```
CREATE USER 'mysql' IDENTIFIED BY 'mysql';
GRANT ALL PRIVILEGES ON *.* TO 'mysql' WITH GRANT OPTION;
```
(In prod, the superuser should have '@localhost' appended to its name.)

Now open /etc/mysql/mariadb.conf.d/50-server.cnf and comment out the following line:
```
bind-address = 127.0.0.1
```
Then restart MariaDB:
```
systemctl restart mariadb
```

Install PostgreSQL in the container:
```
apt install -y postgresql
```
Modify the superuser `postgres` for password authentication and restrict new users:
```
su postgres
psql

ALTER USER postgres WITH PASSWORD 'postgres';
REVOKE ALL ON SCHEMA public FROM public;
GRANT ALL ON SCHEMA public TO postgres;
```
Create a new `pg_hba.conf`:
```
cd /etc/postgresql/<version>/<branch>/
mv pg_hba.conf pg_hba.conf.old
```
```
# new pg_hba.conf
# TYPE  DATABASE        USER            ADDRESS                 METHOD
local   all             postgres                                peer
host    all             postgres        0.0.0.0/0               md5

local   all             all                                     peer
host    all             all             localhost               md5

local   sameuser        all                                     peer
host    sameuser        all             0.0.0.0/0               md5
```
**Warning**: in prod, the postgres user should only be allowed to connect locally,
so the relevant snippet in pg_hba.conf should look something like
```
local   all             postgres                                md5
host    all             postgres        localhost               md5
host    all             postgres        0.0.0.0/0               reject
host    all             postgres        ::/0                    reject
```
Add the following to postgresql.conf:
```
listen_addresses = '*'
```
Now restart PostgreSQL:
```
systemctl restart postgresql
```
**In prod**, users can login remotely but superusers (`postgres` and `mysql`) are only
allowed to login from the database host.

#### Mailman
You should create the following mailing lists from the mail container:
```sh
/opt/mailman3/bin/mailman create syscom@csclub.internal
/opt/mailman3/bin/mailman create syscom-alerts@csclub.internal
/opt/mailman3/bin/mailman create exec@csclub.internal
/opt/mailman3/bin/mailman create ceo@csclub.internal
```
See https://git.uwaterloo.ca/csc/syscom-dev-environment/-/tree/master/mail
for instructions on how to access the Mailman UI from your browser.

If you want to actually see the archived messages, you'll
need to tweak the settings for each list from the UI so that non-member
messages get accepted (by default they get held).


#### Dependencies
Next, install and activate a virtualenv:
```sh
sudo apt install libkrb5-dev libpq-dev python3-dev
python3 -m venv venv
. venv/bin/activate
pip install -r requirements.txt
pip install -r dev-requirements.txt
```

#### Running the application
ceod is a distributed application, with instances on different hosts offering
different services.
Therefore, you will need to run ceod on multiple hosts. Currently, those are
phosphoric-acid, mail and caffeine (in the dev environment, caffeine is
replaced by coffee).

To run ceod on a single host (as root, since the app needs to read the keytab):
```sh
export FLASK_APP=ceod.api
export FLASK_DEBUG=true
flask run -h 0.0.0.0 -p 9987
```

Sometimes changes you make in the source code don't show up while Flask
is running. Stop the flask app (Ctrl-C), run `scripts/clear_cache.sh`, then
restart the app.

## Interacting with the application
To use the TUI:
```
python -m ceo
```
To use the CLI:
```
python -m ceo --help
```

Alternatively, you may use curl to send HTTP requests.

ceod uses [SPNEGO](https://en.wikipedia.org/wiki/SPNEGO) for authentication,
and TLS for confidentiality and integrity. In development mode, TLS can be
disabled.

First, make sure that your version of curl has been compiled with SPNEGO
support:
```sh
curl -V
```
Your should see 'SPNEGO' in the 'Features' section.

Here's an example of making a request to add a user (in the Docker container):
```sh
# If you're root, switch to the ctdalek user first
su ctdalek
# Get a Kerberos TGT (password is krb5)
kinit
# Make the request
curl --negotiate -u : --service-name ceod --delegation always \
    -d '{"uid":"test_1","cn":"Test One","given_name":"Test","sn":"One","program":"Math","terms":["s2021"]}' \
    -X POST http://phosphoric-acid:9987/api/members

# To delete the user:
curl --negotiate -u : --service-name ceod --delegation always \
    -X DELETE http://phosphoric-acid:9987/api/members/test_1

# In prod, use the following base URL instead:
# https://phosphoric-acid.csclub.uwaterloo.ca:9987
```

## Packaging
See [PACKAGING.md](./PACKAGING.md).