Storage

The Blue Alliances writes files to backup and archive data. Examples include storing responses from the FRC API (to allow replaying API responses) and periodic backups of data. Production uses Google Cloud Storage, while the development container writes these files to the local filesystem. The development container can be configured to use an upstream Google Cloud Storage instance as well.

Configuration

tba_dev_config.json/tba_dev_config.local.json exposes two fields to configure storage - storage_mode and storage_path. storage_mode is required to be either local or remote, while storage_path is only necessary if storage_mode is local (and will be ignored when storage_mode is remote).

After syncing over your modified config file, make sure to either restart your dev container or restart the dev_appserver.sh script in the tmux session in order to get the local project to respect the modified config file.

Local

Change the storage_mode property to local, and set the storage_path property to a local file path. The path will be resolved from the root of the project (ex: the-blue-alliance/ folder).

{
    ...
    "storage_mode": "local",
    "storage_path": "ops/dev/storage",
    ...
}

Google Cloud Storage

A local development instance can be configured to point to an upstream Google Cloud Storage bucket. You'll need an upstream Google App Engine instance. Refer to the Google App Engine + Firebase Setup for details. By default, a bucket named the {project}.appspot.com will be used to read/write files from.

Change the storage_mode property to be remote. storage_path can be removed or left as-is - it will be ignored. Additionally, set the google_application_credentials field (details can be found in the development runbook).

{
    ...
    "google_application_credentials": "ops/dev/keys/my-key.json",
    "storage_mode": "remote",
    ...
}

Writing Files

Write files to storage by specifying both a file name and the content. The content should be a string.

import json

from backend.common import storage

def write_file():
    storage.write('file_name.json', json.dumps({'some': 'content'}))

write_file()

Reading Files

Read files from storage by specifying a file name. The content will be None if the file does not exist.

from backend.common import storage

def read_file():
    print(storage.read("nonexistent_file.json"))  # None
    print(storage.read("file_name.json"))  # {'some': 'content'}

read_file()