Version history

Version 5.4

  • PARTICIPANT_FIELDS are now included in data export
  • field_maybe_none
  • Radio buttons can now be accessed by numeric index, e.g. {{ form.my_field.0 }}.
  • Bugfix with numpy data types assigned to model fields
  • Misc improvements and fixes

Version 5.3

  • Bugfix to deleting sessions in devserver
  • {{ static }} tag checks that the file exists
  • In SessionData tab, fix the “next round”/”previous round” icons on Mac
  • Fix to currency formatting in Japanese/Korean/Turkish currency (numbers were displayed with a decimal when there should be none)
  • allow error_message to be run on non-form pages (e.g. live pages)
  • Better error reporting when an invalid value is passed to js_vars
  • Minor fixes & improvements

Version 5.2

  • For compatibility with oTree 3.x, formfield <input> elements now prefix their id attribute with id_. If you use getElementById/querySelector/etc. to select any formfield inputs, you might need to update your selectors.
  • The data export now outputs “time started” as UTC.
  • “Time spent” data export has a column name change. If you have been using the script, you should download the new version.

Version 5.1

  • Breaking changes to REST API

Version 5.0

  • oTree Lite
  • The no-self format
  • The beta method Player.start() has been removed.
  • cu() is now available as an alias for Currency. c() will still work as long as you have from otree.api import Currency as c at the top of your file. More details here.
  • oTree 3.x used two types of tags in templates: {{ }} and {% %}. Starting in oTree 5, however, you can forget about {% %} and just use {{ }} everywhere if you want. More details here.
  • All REST API calls now return JSON

Version 3.3

  • BooleanField now uses radio buttons by default (instead of dropdown)
  • otree zip can now keep your requirements.txt up to date.
  • oTree no longer installs sentry-sdk. If you need Sentry on Heroku, you should add it to your requirements.txt manually.
  • Faster server
  • Faster startup time
  • Faster installation
  • Data export page no longer outputs XLSX files. Instead it outputs CSV files formatted for Excel
  • Admin UI improvements, especially session data tab

Version 3.2

  • Should use less memory and have fewer memory spikes.
  • Enhancements to SessionData and SessionMonitor.

Version 3.1

  • New way to define Roles
  • You can pass a string to formfield, for example {{ formfield 'contribution' }}.

Version 3.0

Live pages

See Live pages.



Custom data export

See Custom data exports.

Other things

  • Python 3.8 is now supported.
  • Speed improvements to devserver & zipserver
  • You can now download a single session’s data as Excel or CSV (through session’s Data tab)
  • When browser bots complete, they keep the last page open
  • group_by_arrival_time: quicker detection if a participant goes offline
  • Browser bots use the REST API to create sessions (see REST).
  • Instead of runprodserver you can now use prodserver (that will be the preferred name going forward).
  • “Page time” data export now has more details such as whether it is a wait page.
  • devserver and zipserver now must use db.sqlite3 as the database.

Version 2.5

  • Removed old runserver command.
  • Deprecated non-oTree widgets and model fields. See here.

Version 2.4

  • zipserver command
  • New MTurk format
  • oTree no longer records participants’ IP addresses.

Version 2.3

  • Various improvements to performance, stability, and ease of use.
  • oTree now requires Python 3.7
  • oTree now uses Django 2.2.
  • Chinese/Japanese/Korean currencies are displayed as 元/円/원 instead of ¥/₩.
  • On Windows, prodserver just launches 1 worker process. If you want more processes, you should use a process manager. (This is due to a limitation of the ASGI server)
  • prodserver uses Uvicorn/Hypercorn instead of Daphne
  • update_my_code has been removed

Version 2.2

  • support for the otreezip format (otree zip, otree unzip)
  • MTurk: in sandbox mode, don’t grant qualifications or check qualification requirements
  • MTurk: before paying participants, check if there is adequate account balance.
  • “next button” is disabled after clicking, to prevent congesting the server with duplicate page loads.
  • Upgrade to the latest version of Sentry
  • Form validation methods should go on the model, not the page. See Dynamic form field validation
  • app_after_this_page
  • Various performance and stability improvements

Version 2.1

  • oTree now raises an error if you use an undefined variable in your template. This will help catch typos like {{ Player.payoff }} or {{ if player.id_in_gruop }}. This means that apps that previously worked may now get a template error (previously, it failed silently). If you can’t remove the offending variable, you can apply the |default filter, like: {{ my_undefined_variable|default:None }}
  • oTree now warns you if you use an invalid attribute on a Page/WaitPage.
  • CSV/Excel data export is done asynchronously, which will fix timeout issues for large files on Heroku.
  • Better performance, especially for “Monitor” and “Data” tab in admin interface