aiohttp-s3-client

The simple module for putting and getting object from Amazon S3 compatible endpoints

Installation

pip install aiohttp-s3-client

Usage

from http import HTTPStatus

from aiohttp import ClientSession
from aiohttp_s3_client import S3Client


async with ClientSession(raise_for_status=True) as session:
    client = S3Client(
        url="http://s3-url",
        session=session,
        access_key_id="key-id",
        secret_access_key="hackme",
        region="us-east-1"
    )

    # Upload str object to bucket "bucket" and key "str"
    async with client.put("bucket/str", "hello, world") as resp:
        assert resp.status == HTTPStatus.OK

    # Upload bytes object to bucket "bucket" and key "bytes"
    async with await client.put("bucket/bytes", b"hello, world") as resp:
        assert resp.status == HTTPStatus.OK

    # Upload AsyncIterable to bucket "bucket" and key "iterable"
    async def gen():
        yield b'some bytes'

    async with client.put("bucket/file", gen()) as resp:
        assert resp.status == HTTPStatus.OK

    # Upload file to bucket "bucket" and key "file"
    async with client.put_file("bucket/file", "/path_to_file") as resp:
        assert resp.status == HTTPStatus.OK

    # Check object exists using bucket+key
    async with client.head("bucket/key") as resp:
        assert resp == HTTPStatus.OK

    # Get object by bucket+key
    async with client.get("bucket/key") as resp:
        data = await resp.read()

    # Make presigned URL
    url = client.presign_url("GET", "bucket/key", expires=60 * 60)

    # Delete object using bucket+key
    async with client.delete("bucket/key") as resp:
        assert resp == HTTPStatus.NO_CONTENT

    # List objects by prefix
    async for result, prefixes in client.list_objects_v2("bucket/", prefix="prefix"):
        # Each result is a list of metadata objects representing an object
        # stored in the bucket.  Each prefixes is a list of common prefixes
        do_work(result, prefixes)

Bucket may be specified as subdomain or in object name:

import aiohttp
from aiohttp_s3_client import S3Client


client = S3Client(url="http://bucket.your-s3-host",
                  session=aiohttp.ClientSession())
async with client.put("key", gen()) as resp:
    ...

client = S3Client(url="http://your-s3-host",
                  session=aiohttp.ClientSession())
async with await client.put("bucket/key", gen()) as resp:
    ...

client = S3Client(url="http://your-s3-host/bucket",
                  session=aiohttp.ClientSession())
async with client.put("key", gen()) as resp:
    ...

Auth may be specified with keywords or in URL:

import aiohttp
from aiohttp_s3_client import S3Client

client_credentials_as_kw = S3Client(
    url="http://your-s3-host",
    access_key_id="key_id",
    secret_access_key="access_key",
    session=aiohttp.ClientSession(),
)

client_credentials_in_url = S3Client(
    url="http://key_id:access_key@your-s3-host",
    session=aiohttp.ClientSession(),
)

Credentials

By default S3Client trying to collect all available credentials from keyword arguments like access_key_id= and secret_access_key=, after that from the username and password from passed url argument, so the next step is environment variables parsing and the last source for collection is the config file.

You can pass credentials explicitly using aiohttp_s3_client.credentials module.

aiohttp_s3_client.credentials.StaticCredentials

import aiohttp
from aiohttp_s3_client import S3Client
from aiohttp_s3_client.credentials import StaticCredentials

credentials = StaticCredentials(
    access_key_id='aaaa',
    secret_access_key='bbbb',
    region='us-east-1',
)
client = S3Client(
    url="http://your-s3-host",
    session=aiohttp.ClientSession(),
    credentials=credentials,
)

aiohttp_s3_client.credentials.URLCredentials

import aiohttp
from aiohttp_s3_client import S3Client
from aiohttp_s3_client.credentials import URLCredentials

url = "http://key@hack-me:your-s3-host"
credentials = URLCredentials(url, region="us-east-1")
client = S3Client(
    url="http://your-s3-host",
    session=aiohttp.ClientSession(),
    credentials=credentials,
)

aiohttp_s3_client.credentials.EnvironmentCredentials

import aiohttp
from aiohttp_s3_client import S3Client
from aiohttp_s3_client.credentials import EnvironmentCredentials

credentials = EnvironmentCredentials(region="us-east-1")
client = S3Client(
    url="http://your-s3-host",
    session=aiohttp.ClientSession(),
    credentials=credentials,
)

aiohttp_s3_client.credentials.ConfigCredentials

Using user config file:

import aiohttp
from aiohttp_s3_client import S3Client
from aiohttp_s3_client.credentials import ConfigCredentials


credentials = ConfigCredentials()   # Will be used ~/.aws/credentials config
client = S3Client(
    url="http://your-s3-host",
    session=aiohttp.ClientSession(),
    credentials=credentials,
)

Using the custom config location:

import aiohttp
from aiohttp_s3_client import S3Client
from aiohttp_s3_client.credentials import ConfigCredentials


credentials = ConfigCredentials("~/.my-custom-aws-credentials")
client = S3Client(
    url="http://your-s3-host",
    session=aiohttp.ClientSession(),
    credentials=credentials,
)

aiohttp_s3_client.credentials.merge_credentials

This function collect all passed credentials instances and return a new one which contains all non-blank fields from passed instances. The first argument has more priority.

import aiohttp
from aiohttp_s3_client import S3Client
from aiohttp_s3_client.credentials import (
    ConfigCredentials, EnvironmentCredentials, merge_credentials
)

credentials = merge_credentials(
    EnvironmentCredentials(),
    ConfigCredentials(),
)
client = S3Client(
    url="http://your-s3-host",
    session=aiohttp.ClientSession(),
    credentials=credentials,
)

aiohttp_s3_client.credentials.MetadataCredentials

Trying to get credentials from the metadata service:

import aiohttp
from aiohttp_s3_client import S3Client
from aiohttp_s3_client.credentials import MetadataCredentials

credentials = MetadataCredentials()

# start refresh credentials from metadata server
await credentials.start()
client = S3Client(
    url="http://your-s3-host",
    session=aiohttp.ClientSession(),
)
await credentials.stop()

Multipart upload

For uploading large files multipart uploading can be used. It allows you to asynchronously upload multiple parts of a file to S3. S3Client handles retries of part uploads and calculates part hash for integrity checks.

import aiohttp
from aiohttp_s3_client import S3Client


client = S3Client(url="http://your-s3-host", session=aiohttp.ClientSession())
await client.put_file_multipart(
    "test/bigfile.csv",
    headers={
        "Content-Type": "text/csv",
    },
    workers_count=8,
)

Parallel download to file

S3 supports GET requests with Range header. It's possible to download objects in parallel with multiple connections for speedup. S3Client handles retries of partial requests and makes sure that file won't be changed during download with ETag header. If your system supports pwrite syscall (Linux, macOS, etc.) it will be used to write simultaneously to a single file. Otherwise, each worker will have own file which will be concatenated after downloading.

import aiohttp
from aiohttp_s3_client import S3Client


client = S3Client(url="http://your-s3-host", session=aiohttp.ClientSession())

await client.get_file_parallel(
    "dump/bigfile.csv",
    "/home/user/bigfile.csv",
    workers_count=8,
)