name: supabase-storage
description: Manage file storage operations in Supabase Storage. Use for uploading, downloading, listing, and deleting files in buckets.

Supabase Storage Operations

Overview

This skill provides file storage operations through the Supabase Storage API. Supports bucket management, file uploads/downloads, listing files, generating URLs, and managing access control.

Prerequisites

Required environment variables:

export SUPABASE_URL="https://your-project.supabase.co"
export SUPABASE_KEY="your-anon-or-service-role-key"

Helper script:
This skill uses the shared Supabase API helper. Make sure to source it:

source "$(dirname "${BASH_SOURCE[0]}")/../../scripts/supabase-api.sh"

Bucket Operations

List Buckets

Get all storage buckets:

source "$(dirname "${BASH_SOURCE[0]}")/../../scripts/supabase-api.sh"

supabase_get "/storage/v1/bucket"

Create Bucket

Create a new storage bucket:

source "$(dirname "${BASH_SOURCE[0]}")/../../scripts/supabase-api.sh"

# Public bucket
supabase_post "/storage/v1/bucket" '{
  "name": "avatars",
  "public": true
}'

# Private bucket
supabase_post "/storage/v1/bucket" '{
  "name": "private-documents",
  "public": false,
  "file_size_limit": 52428800,
  "allowed_mime_types": ["image/png", "image/jpeg", "application/pdf"]
}'

Get Bucket Details

Retrieve bucket information:

source "$(dirname "${BASH_SOURCE[0]}")/../../scripts/supabase-api.sh"

supabase_get "/storage/v1/bucket/avatars"

Update Bucket

Update bucket settings:

source "$(dirname "${BASH_SOURCE[0]}")/../../scripts/supabase-api.sh"

curl -s -X PUT \
    "${SUPABASE_URL}/storage/v1/bucket/avatars" \
    -H "apikey: ${SUPABASE_KEY}" \
    -H "Authorization: Bearer ${SUPABASE_KEY}" \
    -H "Content-Type: application/json" \
    -d '{
      "public": false,
      "file_size_limit": 10485760
    }'

Delete Bucket

Delete a bucket (must be empty):

source "$(dirname "${BASH_SOURCE[0]}")/../../scripts/supabase-api.sh"

supabase_delete "/storage/v1/bucket/old-bucket"

Empty Bucket

Delete all files in a bucket:

source "$(dirname "${BASH_SOURCE[0]}")/../../scripts/supabase-api.sh"

supabase_post "/storage/v1/bucket/avatars/empty" '{}'

File Operations

Upload File

Upload a file to storage:

source "$(dirname "${BASH_SOURCE[0]}")/../../scripts/supabase-api.sh"

BUCKET_NAME="avatars"
FILE_PATH="/path/to/local/image.jpg"
STORAGE_PATH="user-123/profile.jpg"

curl -s -X POST \
    "${SUPABASE_URL}/storage/v1/object/${BUCKET_NAME}/${STORAGE_PATH}" \
    -H "apikey: ${SUPABASE_KEY}" \
    -H "Authorization: Bearer ${SUPABASE_KEY}" \
    -F "file=@${FILE_PATH}"

Upload with upsert (overwrite if exists):

curl -s -X POST \
    "${SUPABASE_URL}/storage/v1/object/${BUCKET_NAME}/${STORAGE_PATH}" \
    -H "apikey: ${SUPABASE_KEY}" \
    -H "Authorization: Bearer ${SUPABASE_KEY}" \
    -H "x-upsert: true" \
    -F "file=@${FILE_PATH}"

Upload with content type:

curl -s -X POST \
    "${SUPABASE_URL}/storage/v1/object/${BUCKET_NAME}/${STORAGE_PATH}" \
    -H "apikey: ${SUPABASE_KEY}" \
    -H "Authorization: Bearer ${SUPABASE_KEY}" \
    -H "Content-Type: image/jpeg" \
    -F "file=@${FILE_PATH}"

Download File

Download a file from storage:

source "$(dirname "${BASH_SOURCE[0]}")/../../scripts/supabase-api.sh"

BUCKET_NAME="avatars"
STORAGE_PATH="user-123/profile.jpg"
OUTPUT_FILE="/path/to/save/downloaded.jpg"

curl -s -X GET \
    "${SUPABASE_URL}/storage/v1/object/${BUCKET_NAME}/${STORAGE_PATH}" \
    -H "apikey: ${SUPABASE_KEY}" \
    -H "Authorization: Bearer ${SUPABASE_KEY}" \
    -o "${OUTPUT_FILE}"

Download to stdout (pipe to other commands):

curl -s -X GET \
    "${SUPABASE_URL}/storage/v1/object/${BUCKET_NAME}/${STORAGE_PATH}" \
    -H "apikey: ${SUPABASE_KEY}" \
    -H "Authorization: Bearer ${SUPABASE_KEY}"

List Files

List files in a bucket:

source "$(dirname "${BASH_SOURCE[0]}")/../../scripts/supabase-api.sh"

BUCKET_NAME="avatars"

supabase_post "/storage/v1/object/list/${BUCKET_NAME}" '{
  "limit": 100,
  "offset": 0,
  "sortBy": {
    "column": "name",
    "order": "asc"
  }
}'

List files in a specific folder:

supabase_post "/storage/v1/object/list/${BUCKET_NAME}" '{
  "prefix": "user-123/",
  "limit": 100
}'

Search files:

supabase_post "/storage/v1/object/list/${BUCKET_NAME}" '{
  "search": "profile",
  "limit": 50
}'

Delete File

Delete a single file:

source "$(dirname "${BASH_SOURCE[0]}")/../../scripts/supabase-api.sh"

BUCKET_NAME="avatars"
STORAGE_PATH="user-123/old-profile.jpg"

supabase_delete "/storage/v1/object/${BUCKET_NAME}/${STORAGE_PATH}"

Delete multiple files:

source "$(dirname "${BASH_SOURCE[0]}")/../../scripts/supabase-api.sh"

BUCKET_NAME="avatars"

supabase_delete "/storage/v1/object/${BUCKET_NAME}" -d '{
  "prefixes": ["user-123/temp/", "user-456/draft/"]
}'

Move/Rename File

Move or rename a file:

source "$(dirname "${BASH_SOURCE[0]}")/../../scripts/supabase-api.sh"

BUCKET_NAME="avatars"
FROM_PATH="user-123/temp.jpg"
TO_PATH="user-123/final.jpg"

supabase_post "/storage/v1/object/move" '{
  "bucketId": "'"${BUCKET_NAME}"'",
  "sourceKey": "'"${FROM_PATH}"'",
  "destinationKey": "'"${TO_PATH}"'"
}'

Copy File

Copy a file to another location:

source "$(dirname "${BASH_SOURCE[0]}")/../../scripts/supabase-api.sh"

BUCKET_NAME="avatars"
SOURCE_PATH="user-123/profile.jpg"
DEST_PATH="user-123/profile-backup.jpg"

supabase_post "/storage/v1/object/copy" '{
  "bucketId": "'"${BUCKET_NAME}"'",
  "sourceKey": "'"${SOURCE_PATH}"'",
  "destinationKey": "'"${DEST_PATH}"'"
}'

URL Generation

Get Public URL

Get public URL for a file (public buckets only):

BUCKET_NAME="avatars"
STORAGE_PATH="user-123/profile.jpg"

PUBLIC_URL="${SUPABASE_URL}/storage/v1/object/public/${BUCKET_NAME}/${STORAGE_PATH}"
echo "Public URL: $PUBLIC_URL"

Create Signed URL

Generate a signed URL for temporary access:

source "$(dirname "${BASH_SOURCE[0]}")/../../scripts/supabase-api.sh"

BUCKET_NAME="private-documents"
STORAGE_PATH="user-123/secret.pdf"
EXPIRES_IN=3600  # 1 hour in seconds

supabase_post "/storage/v1/object/sign/${BUCKET_NAME}/${STORAGE_PATH}" '{
  "expiresIn": '"${EXPIRES_IN}"'
}'

Response will include:

{
  "signedURL": "/storage/v1/object/sign/private-documents/user-123/secret.pdf?token=..."
}

Full URL:

signed_path=$(supabase_post "/storage/v1/object/sign/${BUCKET_NAME}/${STORAGE_PATH}" '{"expiresIn": 3600}' | jq -r '.signedURL')
full_url="${SUPABASE_URL}${signed_path}"
echo "Signed URL: $full_url"

Create Multiple Signed URLs

Generate signed URLs for multiple files:

source "$(dirname "${BASH_SOURCE[0]}")/../../scripts/supabase-api.sh"

BUCKET_NAME="private-documents"

supabase_post "/storage/v1/object/sign/${BUCKET_NAME}" '{
  "paths": ["doc1.pdf", "doc2.pdf", "folder/doc3.pdf"],
  "expiresIn": 3600
}'

Common Patterns

Upload with Progress

#!/bin/bash
source "$(dirname "${BASH_SOURCE[0]}")/../../scripts/supabase-api.sh"

BUCKET_NAME="uploads"
FILE_PATH="/path/to/large-file.zip"
STORAGE_PATH="user-123/backup.zip"

echo "Uploading ${FILE_PATH}..."

curl -X POST \
    "${SUPABASE_URL}/storage/v1/object/${BUCKET_NAME}/${STORAGE_PATH}" \
    -H "apikey: ${SUPABASE_KEY}" \
    -H "Authorization: Bearer ${SUPABASE_KEY}" \
    -F "file=@${FILE_PATH}" \
    --progress-bar -o /dev/null

if [[ $? -eq 0 ]]; then
    echo "Upload successful!"
else
    echo "Upload failed!"
    exit 1
fi

Check if File Exists

source "$(dirname "${BASH_SOURCE[0]}")/../../scripts/supabase-api.sh"

BUCKET_NAME="avatars"
STORAGE_PATH="user-123/profile.jpg"

# Try to get file info
response=$(curl -s -X GET \
    "${SUPABASE_URL}/storage/v1/object/info/${BUCKET_NAME}/${STORAGE_PATH}" \
    -H "apikey: ${SUPABASE_KEY}" \
    -H "Authorization: Bearer ${SUPABASE_KEY}" \
    -w "\n%{http_code}")

http_code=$(echo "$response" | tail -n1)

if [[ $http_code -eq 200 ]]; then
    echo "File exists"
else
    echo "File does not exist"
fi

Batch Upload Files

#!/bin/bash
source "$(dirname "${BASH_SOURCE[0]}")/../../scripts/supabase-api.sh"

BUCKET_NAME="uploads"
LOCAL_DIR="/path/to/files"

for file in "$LOCAL_DIR"/*; do
    filename=$(basename "$file")
    echo "Uploading $filename..."

    curl -s -X POST \
        "${SUPABASE_URL}/storage/v1/object/${BUCKET_NAME}/batch/${filename}" \
        -H "apikey: ${SUPABASE_KEY}" \
        -H "Authorization: Bearer ${SUPABASE_KEY}" \
        -F "file=@${file}"

    echo "✓ Uploaded $filename"
done

Download All Files from Bucket

#!/bin/bash
source "$(dirname "${BASH_SOURCE[0]}")/../../scripts/supabase-api.sh"

BUCKET_NAME="avatars"
OUTPUT_DIR="/path/to/download"

mkdir -p "$OUTPUT_DIR"

# Get file list
files=$(supabase_post "/storage/v1/object/list/${BUCKET_NAME}" '{"limit": 1000}')

# Download each file
echo "$files" | jq -r '.[].name' | while read -r filename; do
    echo "Downloading $filename..."

    curl -s -X GET \
        "${SUPABASE_URL}/storage/v1/object/${BUCKET_NAME}/${filename}" \
        -H "apikey: ${SUPABASE_KEY}" \
        -H "Authorization: Bearer ${SUPABASE_KEY}" \
        -o "${OUTPUT_DIR}/${filename}"

    echo "✓ Downloaded $filename"
done

Image Transformations

Transform images on-the-fly (public buckets):

BUCKET_NAME="avatars"
STORAGE_PATH="user-123/profile.jpg"

# Resize to width 200px
TRANSFORMED_URL="${SUPABASE_URL}/storage/v1/render/image/public/${BUCKET_NAME}/${STORAGE_PATH}?width=200"

# Resize with quality
TRANSFORMED_URL="${SUPABASE_URL}/storage/v1/render/image/public/${BUCKET_NAME}/${STORAGE_PATH}?width=200&quality=80"

# Multiple transformations
TRANSFORMED_URL="${SUPABASE_URL}/storage/v1/render/image/public/${BUCKET_NAME}/${STORAGE_PATH}?width=300&height=300&resize=contain"

Access Control

Storage access is controlled by Storage Policies (RLS) in your Supabase dashboard.

Common policy examples:

Public read, authenticated write:

-- Set in Supabase Dashboard > Storage > Policies
-- Allow public to read
SELECT: true for all users

-- Allow authenticated users to upload their own files
INSERT: auth.uid() = (storage.foldername(name))[1]

User-specific folders:

-- Users can only access files in their own folder
SELECT: auth.uid() = (storage.foldername(name))[1]
UPDATE: auth.uid() = (storage.foldername(name))[1]
DELETE: auth.uid() = (storage.foldername(name))[1]

Error Handling

Common errors:

Security Best Practices

1. Use private buckets for sensitive data
2. Implement Storage Policies (RLS) for access control
3. Set file size limits to prevent abuse
4. Restrict MIME types to expected file types
5. Use signed URLs for temporary access to private files
6. Organize files in user-specific folders (e.g., user-{uuid}/)
7. Never expose service role key to client applications

File Size Limits

• Default max file size: 50MB
• Can be configured per bucket up to 5GB (contact Supabase for larger)
• Check bucket settings for current limit

API Documentation

Full Supabase Storage API documentation: https://supabase.com/docs/guides/storage