6.-working-with-files.md

6. Working with files

For most applications we need to use files, and also share these files between functions. That's why Brane has a shared filesystem. This filesystem is available as/data for container-based functions.

{% hint style="warning" %} The /data directory is only available when running a remote session as part of a instance. {% endhint %}

{% hint style="info" %} With brane test , any directory can be be mounted as /datausing the--dataoption. {% endhint %}

Consider the container package below:

{% tabs %} {% tab title="run.py" %}

#!/usr/bin/env python3
import os
import sys
import yaml

from wordcloud import WordCloud
from typing import List
import matplotlib.pyplot as plt

def create(words: List[str], file: str) -> str:
  wordcloud = WordCloud(max_font_size=40).generate(' '.join(words))
  plt.imshow(wordcloud, interpolation='bilinear')
  plt.axis("off")
  plt.savefig(file)

  return file

if __name__ == "__main__":
  command = sys.argv[1]
  argument_file = os.environ["FILE"]
  argument_words = [
    os.environ[f"WORDS_{i}"] for i in range(int(os.environ["WORDS"]))
  ]
  functions = {
    "create": create,
  }
  output = functions[command](argument_words, argument_file)
  print(yaml.dump({"output": output}))

{% endtab %}

{% tab title="container.yml" %}

name: wordcloud
version: 1.0.0
kind: compute

dependencies:
  - python3
  - python3-pip
  - python3-yaml

install:
  - pip3 install wordcloud

files:
  - run.py

entrypoint:
  kind: task
  exec: run.py

actions:
  'create':
    command:
      args:
        - create

    input:
      - type: string[]
        name: words

      - type: string
        name: file

    output:
      - type: string
        name: output

{% endtab %} {% endtabs %}

If we pass /data/wordcloud.png as the file paramters the word cloud image will be available for subsequent function calls, and from the JupyterLab IDE (Fig 1).

Instead of copy-pasting the source code files for packages, they can also be shared through GitHub:

$ brane import onnovalkering/brane --context ./examples/wordcount/wordcloud

{% hint style="warning" %} We still have to publish this package to the Brane instance seperatly. {% endhint %}