IOI Printing System

The IOI Printing System handles all print requests in the International Olympiad in Informatics, during the contests and the translation meetings. The system has been developed for and was first used in the IOI 2017 in Tehran, Iran.

The system supports the following tasks and requests:

• Print requests from contestants during the contest (via a custom printer installed on all contestants machines) [contestant]
• Call staff requests from the IOI Contest Management System [cms_request]
• Print requests from the IOI Translation System during the translation meetings [translation]
• Custom mass print requests [mass]

Installation

To run the project, you need to install docker and docker-compose. (It has been deployed and tested with docker 17.06.0-ce and docker-compose 1.14.0, but it should work with newer versions as well.)

After that, clone the project using the following command:

git clone git_address/print-system.git

Then configure the project in docker-compose.yml (descriptions on how to configure is commented in the file), and run:

docker-compose up

(You might get into errors if cups server is running or if someone else is using ports 631, 5000, or 6631.)

That's it! You have the printing system up and ready for work!

For running on actual server you might want to run docker-compose in daemon mode:

docker-compose up -d

Check out docker-compose documentation for more info.

How to Use

Configure printers

Go to http://printer_server_address:6631/, it is cups server configuration page:

1. Go to Administration page, login with predefined username admin and password ioi.
2. Click on Add Printer, select Internet Printing Protocol (ipp), click Continue.
3. Write the network printer address in Connection, click Continue. (Check your printer manual to find its ipp address)
4. Set a Name for your printer and make sure Share This Printer is selected, click Continue. (The Name you use for your printer are the ones that you use in configuring printers in ioiprint in docker-compose.yml)
5. Select Generic in the Make section, click Continue.
6. Select Generic IPP Everywhere Printer (en) in the Model section, click Continue.
7. Set default options for your printer, click Set default options.
8. Play a little with printer default options and make sure print requests are handled correctly in the printer. You can use Maitenance -> Print Test Page in the printer page to test printing.

You can also add classes to assign a single name to multiple printers:

1. Go to Administration page, click on Add Class.
2. Set a Name for your class and select printers you want in the Members section, click Continue. (The Name you use for your class are the ones that you use in configuring printers in ioiprint in docker-compose.yml)

Then put your printer or class names in docker-compose.yml (You can have a printer for each contest zone and also one default printer for mass and translation requests)

For contestants print requests

You should add a network printer with the address http://print_server_address:631/printers/PRINTER_NAME on all contestants' computers. (This link can be helpful) PRINTER_NAME is configurable in docker-compose.yml. (It is ioi_printer by default)

The contestants can print using this printer during contest and it will be printed on the printer configured for that zone.

You can also change the templates used for rendering the first page and the last page of the prints by changing the first.html.jinja2 and last.html.jinja2 in ioiprint/template directory (They are in Jinja2 format).

For call staff requests from CMS

You should add print server address in CMS and it should work.

For testing you can use scripts/cms_request.sh (You should change PRINT_SERVER_ADDRESS).

You can also change the template used for rendering the prints by changing the request.html.jinja2 in ioiprint/template directory (They are in Jinja2 format).

For custom translation requests from Translation System

You should add print server address in Translation System and it should work.

For testing you can use scripts/translation.sh (You should change PRINT_SERVER_ADDRESS).

(Translation System also uses the mass request for non-custom prints.)

You can also change the template used for rendering the prints by changing the translation.html.jinja2 in ioiprint/template directory (They are in Jinja2 format).

For custom printing

You can use scripts/mass.sh (You should change PRINT_SERVER_ADDRESS).

Service Details

This service is consisted of three docker containers that are explained in details below:

ioiprint

An http server running on port 5000 (you can change it in docker-compose.yml).

There are 5 type of requests system can handle:

upload

endpoint: /upload
method: POST
parameters: pdf -> a pdf file in multi-part form data
output: uploaded_file_name -> Used in other requests

You should upload a pdf file before using mass, contestant or translation requests. This endpoint is used to upload files and it will give back the file name in the response body. You should use this file name in the next request.

mass

endpoint: /mass
method: POST
parameters: filename -> output of previously called upload request
            printer -> printer or class name that is configured in cups-back server
                       (If not given default printer is used)
            count -> number of times the system should print the file

This will print the file previously uploaded count times on the printer specified.

translation

endpoint: /translation
method: POST
parameters: filename -> output of previously called upload request
            country_code -> country code of the translating country (e.g. IR)
            country_name -> country name of the translating country (e.g. Iran)
            count -> number of times the system should print the file

This will add a first page and print the file previously uploaded count times on default printer.

cms_request

endpoint: /cms_request
method: POST
parameters: request_message -> The request message (e.g. Restroom)
            ip -> IP of the contestant computer

This will print a page with contestant info and request message on the printer configured for the contestant zone.

contestant

endpoint: /contestant
method: POST
parameters: filename -> output of previously called upload request
            ip -> IP of the contestant computer
            cups_job_id -> The print job id of the cups server requesting this print

This will add a first and last page to the file and print it on the printer configured for the contestant zone. (This endpoint is automatically called from cups-front)

cups-front

A cups server running on port 631 (You can change it in docker-compose.yml).

This cups server exposes a printer named ioi_printer, whenever a print request is received on this printer it would call upload and contestant on ioiprint to do the actual printing. The printer is a cups-pdf pdf printer and a cups filter named ioi-filter is used to do this. (You can check the code in cups directory)

cups-back

A cups server running on port 6631 (You can change it in docker-compose.yml).

This cup server is the one that all printers are configured on and the actual printings are happening here. All print requests from ioiprint comes to this cups server.

Changing Contestant Data Source

By default the system will get contestant data from the IOI Network Administration System, and the address is configurable in docker-compose.yml.

If you want to change the source of contestant data (e.g. to read it from a file) you should change the get_contestant_data function in ioiprint/contestant_data.py file. The input of the function is the ip of the contestant's computer. The output should be a python dictionary consisting of the following keys:

• contestant_id: ID of the contestant
• contestant_name: Name of the contestant
• contestant_country: Country name of the contestant
• zone: Zone that contestant sits in (It is used for determining which printer should we use for this contestant)
• desk_id: ID of the contestant's desk
• desk_image_url or desk_image_path: The SVG image of the map showing where the contestant is sitting. It will be downloaded if you provide desk_image_url or you should use desk_image_path if the file is on the computer already. (Please note that the path should be a path inside the docker container. e.g. /usr/src/ioiprint/svgs/contestant1.svg)

License

This software is distributed under the MIT license (see LICENSE.txt), and uses third party libraries that are distributed under their own terms (see LICENSE-3RD-PARTY.txt).

Copyright

Copyright (c) 2017, IOI 2017 Host Technical Committee