add wrapper to rasterio.open with env?

[j08lue]

Directly reading from object storage with rasterio is a very nice thing and people have gotten this to work with the following code (from the forums):

import boto3
import rasterio
from rasterio.session import AWSSession
import numpy as np

BUCKET = 'DIAS'

KEY = 'Sentinel-2/MSI/L2A/2018/08/09/S2A_MSIL2A_20180809T105031_N0208_R051_T31TCG_20180809T141746.SAFE/GRANULE/L2A_T31TCG_A016350_20180809T105627/IMG_DATA/R10m/T31TCG_20180809T105031_B03_10m.jp2'

access_key = 'anystring'
secret_key = 'anystring'

session = boto3.Session(aws_access_key_id=access_key,
                        aws_secret_access_key=secret_key)

with rasterio.Env(AWSSession(session), AWS_S3_ENDPOINT='data.cloudferro.com', AWS_HTTPS='NO', AWS_VIRTUAL_HOSTING='FALSE') as env:
    print(env.options)
    with rasterio.open('/vsis3/{}/{}'.format(BUCKET, KEY), 'r') as ds:
        array = ds.read(1)

print(array.shape)

Since everything here is static except for the key, we could consider adding a little convenience context manager, that allows you to do like

with eodata_rasterio_open(key) as ds:
    pass