minio

Use this skill when you need to:

• Upload/download files to S3-compatible storage
• Manage buckets (create, list, delete)
• Generate pre-signed URLs for temporary file access
• List and search objects in storage
• Mirror/sync directories between local and remote

---

1. Deploy MinIO server or use MinIO Play (public test server)
2. Get access credentials (Access Key and Secret Key)
3. Install MinIO Client (mc)

Install MinIO Client

```bash

# macOS

brew install minio/stable/mc

# Linux (amd64)

curl -O https://dl.min.io/client/mc/release/linux-amd64/mc

chmod +x mc && sudo mv mc /usr/local/bin/

# Verify installation

mc --version

```

Set Environment Variables

```bash

export MINIO_ENDPOINT="play.min.io"

export MINIO_ACCESS_KEY="your-access-key"

export MINIO_SECRET_KEY="your-secret-key"

```

For testing, use MinIO Play (public sandbox):

```bash

export MINIO_ENDPOINT="play.min.io"

export MINIO_ACCESS_KEY="Q3AM3UQ867SPQQA43P2F"

export MINIO_SECRET_KEY="zuf+tfteSlswRu7BJ86wekitnifILbZam1KYY3TG"

```

Configure mc Alias

```bash

mc alias set myminio https://${MINIO_ENDPOINT} ${MINIO_ACCESS_KEY} ${MINIO_SECRET_KEY}

```

---

> Important: When using $VAR in a command that pipes to another command, wrap the command containing $VAR in bash -c '...'. Due to a Claude Code bug, environment variables are silently cleared when pipes are used directly.

> ```bash

> bash -c 'curl -s "https://api.example.com" -H "Authorization: Bearer $API_KEY"' | jq .

> ```

1. List Buckets

```bash

mc ls myminio

```

2. Create a Bucket

```bash

mc mb myminio/my-bucket

```

3. Upload a File

```bash

# Upload single file

mc cp /path/to/file.txt myminio/my-bucket/

# Upload with custom name

mc cp /path/to/file.txt myminio/my-bucket/custom-name.txt

# Upload directory recursively

mc cp --recursive /path/to/folder/ myminio/my-bucket/folder/

```

4. Download a File

```bash

# Download single file

mc cp myminio/my-bucket/file.txt /local/path/

# Download entire bucket

mc cp --recursive myminio/my-bucket/ /local/path/

```

5. List Objects in Bucket

```bash

# List all objects

mc ls myminio/my-bucket

# List recursively with details

mc ls --recursive --summarize myminio/my-bucket

```

6. Delete Objects

```bash

# Delete single file

mc rm myminio/my-bucket/file.txt

# Delete all objects in bucket

mc rm --recursive --force myminio/my-bucket/

# Delete bucket (must be empty)

mc rb myminio/my-bucket

```

7. Generate Pre-signed URL

Create temporary shareable links:

```bash

# Download URL (expires in 7 days by default)

mc share download myminio/my-bucket/file.txt

# Download URL with custom expiry (max 7 days)

mc share download --expire 2h myminio/my-bucket/file.txt

# Upload URL (for external uploads)

mc share upload myminio/my-bucket/uploads/

```

8. Mirror/Sync Directories

```bash

# One-way sync local to remote

mc mirror /local/folder/ myminio/my-bucket/folder/

# One-way sync remote to local

mc mirror myminio/my-bucket/folder/ /local/folder/

# Watch and sync changes continuously

mc mirror --watch /local/folder/ myminio/my-bucket/folder/

```

9. Get Object Info

```bash

# Get file metadata

mc stat myminio/my-bucket/file.txt

# Get bucket info

mc stat myminio/my-bucket

```

10. Search Objects

```bash

# Find by name pattern

mc find myminio/my-bucket --name "*.txt"

# Find files larger than 10MB

mc find myminio/my-bucket --larger 10MB

# Find files modified in last 7 days

mc find myminio/my-bucket --newer-than 7d

```

---

For environments without mc, use pre-signed URLs with curl:

Upload with Pre-signed URL

```bash

# First, generate upload URL with mc

UPLOAD_URL=$(bash -c 'mc share upload --json myminio/my-bucket/file.txt' | jq -r '.share')

# Then upload with curl

curl -X PUT --upload-file /path/to/file.txt "$UPLOAD_URL"

```

Download with Pre-signed URL

```bash

# Generate download URL

DOWNLOAD_URL=$(bash -c 'mc share download --json myminio/my-bucket/file.txt' | jq -r '.share')

# Download with curl

curl -o /local/path/file.txt "$DOWNLOAD_URL"

```

---

For direct API access without mc (simple authentication):

```bash

#!/bin/bash

# minio-upload.sh - Upload file to MinIO

bucket="$1"

file="$2"

host="${MINIO_ENDPOINT}"

s3_key="${MINIO_ACCESS_KEY}"

s3_secret="${MINIO_SECRET_KEY}"

resource="/${bucket}/${file}"

content_type="application/octet-stream"

date=$(date -R)

signature_string="PUT\n\n${content_type}\n${date}\n${resource}"

signature=$(echo -en "${signature_string}" | openssl sha1 -hmac "${s3_secret}" -binary | base64)

curl -X PUT -T "${file}" --header "Host: ${host}" --header "Date: ${date}" --header "Content-Type: ${content_type}" --header "Authorization: AWS ${s3_key}:${signature}" "https://${host}${resource}"

```

Usage:

```bash

chmod +x minio-upload.sh

./minio-upload.sh my-bucket myfile.txt

```

---

MinIO is fully compatible with AWS CLI:

```bash

# Configure AWS CLI for MinIO

aws configure set aws_access_key_id "${MINIO_ACCESS_KEY}"

aws configure set aws_secret_access_key "${MINIO_SECRET_KEY}"

aws configure set default.s3.signature_version s3v4

# List buckets

aws --endpoint-url "https://${MINIO_ENDPOINT}" s3 ls

# Upload file

aws --endpoint-url "https://${MINIO_ENDPOINT}" s3 cp file.txt s3://my-bucket/

# Download file

aws --endpoint-url "https://${MINIO_ENDPOINT}" s3 cp s3://my-bucket/file.txt ./

# List objects

aws --endpoint-url "https://${MINIO_ENDPOINT}" s3 ls s3://my-bucket/

```

---

Set Bucket to Public Read

```bash

mc anonymous set download myminio/my-bucket

```

Set Bucket to Private

```bash

mc anonymous set none myminio/my-bucket

```

Apply Custom Policy

```bash

# Create policy.json

cat > /tmp/policy.json << 'EOF'

{

"Version": "2012-10-17",

"Statement": [

{

"Effect": "Allow",

"Principal": {"AWS": ["*"]},

"Action": ["s3:GetObject"],

"Resource": ["arn:aws:s3:::my-bucket/public/*"]

}

]

}

EOF

mc anonymous set-json /tmp/policy.json myminio/my-bucket

```

---

1. Use mc for most operations - It handles authentication and signing automatically
2. Pre-signed URLs for external access - Share files without exposing credentials
3. Use port 9000 for API - Port 9001 is typically the web console
4. Set appropriate expiry - Pre-signed URLs should expire as soon as practical (max 7 days)
5. Use mirror for backups - mc mirror --watch for continuous sync
6. Bucket naming rules - Lowercase, 3-63 characters, no underscores or consecutive dots