s3-bulk-upload

# S3 Bulk Upload

Upload files to S3 with automatic organization using first-character prefixes (e.g., `a/apple.txt`, `b/banana.txt`, `0-9/123.txt`).

## Quick Start

Use the included script for bulk uploads:

```bash
# Basic upload
./s3-bulk-upload.sh ./files my-bucket

# Dry run to preview
./s3-bulk-upload.sh ./files my-bucket --dry-run

# Use sync mode (faster for many files)
./s3-bulk-upload.sh ./files my-bucket --sync

# With storage class
./s3-bulk-upload.sh ./files my-bucket --storage-class STANDARD_IA
```

## Prerequisites

Verify AWS credentials are configured:

```bash
aws sts get-caller-identity
```

If this fails, ensure `AWS_ACCESS_KEY_ID` and `AWS_SECRET_ACCESS_KEY` are set, or configure via `aws configure`.

## Organization Logic

Files are organized by the first character of their filename:

| First Character | Prefix |
|-----------------|--------|
| `a-z` | Lowercase letter (e.g., `a/`, `b/`) |
| `A-Z` | Lowercase letter (e.g., `a/`, `b/`) |
| `0-9` | `0-9/` |
| Other | `_other/` |

## Single File Upload

Upload a single file with automatic prefix:

```bash
FILE="example.txt"
BUCKET="my-bucket"

# Compute prefix from first character
FIRST_CHAR=$(echo "${FILE}" | cut -c1 | tr '[:upper:]' '[:lower:]')
if [[ "$FIRST_CHAR" =~ [a-z] ]]; then
  PREFIX="$FIRST_CHAR"
elif [[ "$FIRST_CHAR" =~ [0-9] ]]; then
  PREFIX="0-9"
else
  PREFIX="_other"
fi

aws s3 cp "$FILE" "s3://${BUCKET}/${PREFIX}/${FILE}"
```

## Bulk Upload

Upload all files from a directory:

```bash
SOURCE_DIR="./files"
BUCKET="my-bucket"

for FILE in "$SOURCE_DIR"/*; do
  [ -f "$FILE" ] || continue
  BASENAME=$(basename "$FILE")
  FIRST_CHAR=$(echo "$BASENAME" | cut -c1 | tr '[:upper:]' '[:lower:]')

  if [[ "$FIRST_CHAR" =~ [a-z] ]]; then
    PREFIX="$FIRST_CHAR"
  elif [[ "$FIRST_CHAR" =~ [0-9] ]]; then
    PREFIX="0-9"
  else
    PREFIX="_other"
  fi

  aws s3 cp "$FILE" "s3://${BUCKET}/${PREFIX}/${BASENAME}"
done
```

## Efficient Bulk Sync

For large uploads, stage files with symlinks th...