First Trial Data Uploads

Tony Lorenzo, May 18, 2020

This post describes the first test trial of the Solar Forecast Arbiter framework, and a script that participants can uses to generate and post random forecasts for the trial. Read about the full testing plans in the Trials Testing blog post.

To set up a trial, the framework administrators perform the following steps:

  1. Work with stakeholders to define trial parameters
  2. Create anonymous users
  3. Create Site metadata and Observation metadata (as required)
  4. For each anonymous user, create the Forecast objects
  5. Create daily and final Reports of how the forecasts perform

Trial participants will receive an email with their unique, anonymous username to use specifically for the trial along with a link to set a password. Participants then use this trial username and password to upload forecast values for each forecast object assigned to them. In most cases, the framework will restrict uploads so only those made before the forecast issue time of day are valid.

Example Script

An example script to upload random forecast values for each of the user’s forecast objects in a trial can be found at the end of this post and in this gist.

This script uses the solarforecastarbiter-core library to interact with the Solar Forecast Arbiter API. First, a token for API access is requested using the username and password for the anonymous trial user. The script expects a path to a file with the username and password of this user seperated by a new line like


A list of forecasts is then retrieved from the API and filtered for those forecasts relevant to the Trial. For each of these forecasts, a check is performed to determine if the current time is within 10 minutes of the next issue time of the forecast. If it is, a random set of values is uploaded to the API for the expected forecast time range. Otherwise, the script moves on to trying the next forecast in the list.

To run the script, users can make use of the solarforecastarbiter-core Docker image which includes a Python installation and all requirements. Otherwise, the solarforecastarbiter-core Python package can be installed from the Github repository or via pip with the command pip install git+ The script should be run periodically to generate new forecasts, either using cron jobs or a cron Python framework like schedule. Further documentation for the solarforecastarbiter-core Python package can be found at