strukto-ai--mirage/docs/python/resource/s3.mdx

---
title: S3
description: Mount AWS S3 or S3-compatible buckets as a Mirage filesystem with async access, caching, and shell commands.
icon: aws
---
The S3 resource mounts an Amazon S3 bucket (or any S3-compatible service) at
some prefix such as `/s3/`. All operations involve network I/O to the remote
object store. Uses aioboto3 for async S3 access.

Compatible with: AWS S3, MinIO, Cloudflare R2, Supabase Storage,
DigitalOcean Spaces, and any S3-compatible service.

## Config

```python
from mirage import MountMode, Workspace
from mirage.resource.s3 import S3Resource, S3Config

config = S3Config(
    bucket="my-bucket",
    region="us-east-1",
    # Optional:
    # aws_access_key_id="...",
    # aws_secret_access_key="...",
    # aws_profile="my-profile",
    # endpoint_url="http://localhost:9000",  # MinIO
    # path_style=True,  # For MinIO/R2
    # timeout=30,
    # proxy="http://proxy:8080",
)

resource = S3Resource(config)
ws = Workspace({"/s3": resource}, mode=MountMode.READ)
```

`S3Resource(config)` takes an `S3Config` object with the bucket name and
optional credentials, endpoint, and connection settings. Both `READ` and
`WRITE` modes are supported.

## Filesystem Layout

The S3 resource maps S3 object keys to virtual paths under the mount prefix.
S3 "directories" are prefix-based - there are no real directory objects.

For example, if bucket `my-bucket` contains:

```text
data/file.txt
data/config.json
reports/q1.csv
reports/q2.csv
```

Then mounting at `/s3/` exposes:

```text
/s3/
  data/
    file.txt
    config.json
  reports/
    q1.csv
    q2.csv
```

Path mapping: virtual `/s3/data/file.txt` maps to S3 key `data/file.txt`.

## Cache

The S3 resource uses `IndexCacheStore` with `index_ttl = 600` (10 minutes).
Directory listings are cached for up to 600 seconds before being refreshed
from S3. This reduces API calls for repeated directory traversals.

## Example

```python
import asyncio

from mirage import MountMode, Workspace
from mirage.resource.s3 import S3Resource, S3Config

config = S3Config(
    bucket="my-bucket",
    region="us-east-1",
)

resource = S3Resource(config)


async def main() -> None:
    ws = Workspace({"/s3/": resource}, mode=MountMode.READ)

    r = await ws.execute("ls /s3/")
    print(await r.stdout_str())

    r = await ws.execute("cat /s3/data/file.txt")
    print(await r.stdout_str())

    r = await ws.execute("tree /s3/")
    print(await r.stdout_str())

    r = await ws.execute("find /s3/ -name '*.json'")
    print(await r.stdout_str())

    r = await ws.execute("grep example /s3/data/config.json")
    print(await r.stdout_str())

    r = await ws.execute("stat /s3/data/file.txt")
    print(await r.stdout_str())


if __name__ == "__main__":
    asyncio.run(main())
```

## Shell Commands

The S3 resource supports the full set of shell commands since it operates
on real file content (text, binary, JSON, CSV, etc.). Large files benefit
from range reads to avoid downloading entire objects.

### Read Commands

| Command         | Notes                                      |
| --------------- | ------------------------------------------ |
| `cat`           | Read file content                          |
| `head` / `tail` | First/last N lines                         |
| `grep` / `rg`   | Pattern search (file or directory level)   |
| `jq`            | Query JSON fields                          |
| `wc`            | Line/word/byte counts                      |
| `stat`          | File metadata (name, size, type, modified) |
| `find`          | Recursive search with `-name`, `-maxdepth` |
| `tree`          | Directory tree view                        |
| `nl`            | Number lines                               |
| `du`            | Disk usage summary                         |
| `file`          | Detect file type                           |
| `strings`       | Extract printable strings from binary      |
| `xxd`           | Hex dump                                   |
| `md5`           | MD5 checksum                               |
| `sha256sum`     | SHA-256 checksum                           |

### Text Processing

| Command    | Notes                                       |
| ---------- | ------------------------------------------- |
| `awk`      | Pattern scanning and processing             |
| `sed`      | Stream editor                               |
| `tr`       | Translate or delete characters              |
| `sort`     | Sort lines                                  |
| `uniq`     | Remove duplicate lines                      |
| `cut`      | Extract fields/columns                      |
| `join`     | Join lines on a common field                |
| `paste`    | Merge lines side by side                    |
| `column`   | Columnate output                            |
| `fold`     | Wrap lines to a specified width             |
| `expand`   | Convert tabs to spaces                      |
| `unexpand` | Convert spaces to tabs                      |
| `fmt`      | Simple text formatter                       |
| `rev`      | Reverse lines                               |
| `tac`      | Concatenate and print in reverse            |
| `look`     | Display lines beginning with a given string |
| `shuf`     | Shuffle lines                               |
| `tsort`    | Topological sort                            |
| `comm`     | Compare two sorted files                    |
| `cmp`      | Compare two files byte by byte              |
| `diff`     | Compare files line by line                  |
| `patch`    | Apply a diff patch                          |
| `iconv`    | Character encoding conversion               |

### File Operations

| Command  | Notes                                 |
| -------- | ------------------------------------- |
| `cp`     | Copy files                            |
| `mv`     | Move/rename files                     |
| `rm`     | Remove files                          |
| `mkdir`  | Create directories                    |
| `touch`  | Create empty file or update timestamp |
| `ln`     | Create symbolic links                 |
| `tee`    | Write stdin to file and stdout        |
| `mktemp` | Create temporary file                 |
| `split`  | Split file into pieces                |
| `csplit` | Split file by context                 |

### Path Utilities

| Command    | Notes                      |
| ---------- | -------------------------- |
| `basename` | Strip directory from path  |
| `dirname`  | Strip filename from path   |
| `realpath` | Resolve path               |
| `readlink` | Print symbolic link target |
| `ls`       | List directory contents    |

### Compression

| Command  | Notes                 |
| -------- | --------------------- |
| `gzip`   | Compress files        |
| `gunzip` | Decompress gzip files |
| `zip`    | Create zip archives   |
| `unzip`  | Extract zip archives  |
| `tar`    | Archive files         |
| `zcat`   | Cat compressed files  |
| `zgrep`  | Grep compressed files |

### Encoding

| Command  | Notes                |
| -------- | -------------------- |
| `base64` | Base64 encode/decode |

### Data Format Support

Commands with format-specific variants for structured data files:

| Format  | Extension  | Variants                                       |
| ------- | ---------- | ---------------------------------------------- |
| Parquet | `.parquet` | cat, head, tail, wc, stat, cut, grep, ls, file |
| Feather | `.feather` | cat, head, tail, wc, stat, cut, grep, ls, file |
| ORC     | `.orc`     | cat, head, tail, wc, stat, cut, grep, ls, file |
| HDF5    | `.hdf5`    | cat, head, tail, wc, stat, cut, grep, ls, file |

These variants auto-detect the format by extension and convert to
tabular text (CSV) for processing.

## Use Cases

- **AI agents accessing cloud data**: Mount S3 buckets for agents to read and process remote datasets
- **Data pipelines**: Read and write S3 objects with shell-like commands
- **Sandboxed cloud storage access**: Restrict agent operations to a specific bucket and prefix
- **FUSE mounting**: Expose S3 buckets through a virtual FUSE mount for external tools

## Scoping a resource to a key prefix

Pass `key_prefix: str | None = None` to `S3Config` to transparently scope every operation to a subpath of the bucket:

```python
S3Resource(S3Config(
    bucket="app-data",
    region="eu-west-1",
    key_prefix=f"users/{user_id}/",
))
```

When set, every read/write/list/stat/copy/rename/delete operation is transparently scoped to that bucket subpath. Agents see clean paths like `/data/notes.md`; the underlying bucket key is `users/{user_id}/data/notes.md`. Useful for multi-tenant systems. Pairs naturally with STS AssumeRole session policies for AWS-side enforcement. Unset behavior is unchanged.

**Normalization:** leading slashes are stripped and a trailing slash is added automatically. Both `None` and an empty string are treated as "no prefix."