Django Storages for S3

What it does

When your agent uses it

• Moving Django static and media files from local disk to an S3 bucket
• Splitting public CDN-served files from private files served by presigned URLs
• Adding direct browser-to-S3 uploads to a Django form or API
• Writing tests for storage code without calling real S3
• Auditing an existing S3 storage setup in settings.py

Example prompts

• “Move our Django media uploads to S3 using the new STORAGES setting and keep static files under a separate prefix.”
• “Add a private bucket backend for invoices and return presigned download links that expire quickly.”
• “Replace the S3 calls in our upload tests with InMemoryStorage.”
• “Review settings.py and tell me whether our S3 configuration follows least-privilege IAM practice.”

Requirements

• Python with `django-storages` and `boto3`
• An AWS S3 bucket and credentials or an IAM role

Workflow steps

5 steps, taken from the first numbered list in SKILL.md.

1. 1Install & register — pip install django-storages[s3] boto3; add "storages" to INSTALLED_APPS
2. 2Configure credentials — Load from env vars or rely on an attached IAM role; never hardcode
3. 3Wire the STORAGES dict — Set default (media) and staticfiles backends with separate location prefixes
4. 4Add named backends — Split public vs. private buckets/ACLs as additional STORAGES entries when needed
5. 5Verify & test — Run collectstatic, confirm uploads land in S3, and mock S3 in tests with InMemoryStorage or moto

What it can do on your machine

Read from SKILL.md and the folder at commit 1be15d8. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  Shell commands in SKILL.md call:

  • pip

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  Links to these hosts (documentation or services it may open):

  • jeffallan.github.io

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names these keys or tokens, usually read from environment variables:

  • AWS_SECRET_ACCESS_KEY

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Django Storages for S3 loads about 1.9k tokens when it runs, and up to ~6.8k if it reads all its reference files. Until then it costs about 133 tokens; SKILL.md has 635 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~133

When it runs · the whole SKILL.md, loaded when a task matches

~1.9k

With references · SKILL.md plus every file in references/, read only if the agent opens them

~6.8k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from Jeffallan/claude-skills at commit 1be15d8, republished under its MIT licence (© Jeffallan). 635 words, ~1,856 tokens.

name

django-storages-s3

description

Use when configuring Django to store static and media files on AWS S3 with django-storages. Invoke when working with the STORAGES setting, S3 buckets, presigned URLs, CloudFront, or boto3-backed file storage in settings.py. Configures the Django 4.2+ STORAGES dict, public/private custom backends, presigned GET/POST URLs, IAM policies, and S3 mocking for tests. Trigger terms: django-storages, S3, boto3, S3Boto3Storage, STORAGES, presigned URL, CloudFront, media files, collectstatic, AWS_STORAGE_BUCKET_NAME.

license

MIT

metadata.author

https://github.com/awais786

metadata.version

1.0.0

metadata.domain

backend

metadata.triggers

django-storages, S3, boto3, S3Boto3Storage, STORAGES, presigned URL, CloudFront, media files, collectstatic

metadata.role

specialist

metadata.scope

implementation

metadata.output-format

code

metadata.related-skills

django-expert

# settings.py
import os

AWS_STORAGE_BUCKET_NAME = os.environ["AWS_STORAGE_BUCKET_NAME"]
AWS_S3_REGION_NAME = os.environ.get("AWS_S3_REGION_NAME", "us-east-1")
AWS_S3_CUSTOM_DOMAIN = f"{AWS_STORAGE_BUCKET_NAME}.s3.{AWS_S3_REGION_NAME}.amazonaws.com"
# On EC2/ECS/Lambda, omit keys entirely — boto3 uses the attached IAM role.

STORAGES = {
    "default": {  # media uploads
        "BACKEND": "storages.backends.s3boto3.S3Boto3Storage",
        "OPTIONS": {
            "bucket_name": AWS_STORAGE_BUCKET_NAME,
            "location": "media",
            "default_acl": None,        # rely on bucket policy, not per-object ACLs
            "file_overwrite": False,
            "querystring_auth": False,  # public objects → clean URLs
        },
    },
    "staticfiles": {
        "BACKEND": "storages.backends.s3boto3.S3StaticStorage",
        "OPTIONS": {
            "bucket_name": AWS_STORAGE_BUCKET_NAME,
            "location": "static",
        },
    },
}

MEDIA_URL = f"https://{AWS_S3_CUSTOM_DOMAIN}/media/"
STATIC_URL = f"https://{AWS_S3_CUSTOM_DOMAIN}/static/"

# models.py — uploads go straight to S3 on save()
from django.db import models

class Document(models.Model):
    file = models.FileField(upload_to="docs/")  # uses STORAGES["default"]

© Jeffallan, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 4 other files (references) in skills/django-storages-s3 of Jeffallan/claude-skills.

• SKILL.md
• references/configuration.md
• references/custom-backends.md
• references/presigned-urls.md
• references/testing-storages.md

Open the folder on GitHubat commit 1be15d8