I have already asked this question in GIS stack exchange  and stack overflow but received no response:

 

I am trying to write a function which will help me construct a `rasterio` memory file and return the dataset reader object so I can then play around with it as needed. I am trying to avoid `with` statements because I would like to allow the user to read and write as they deem necessary. This is what I have so far:

 

 

    from rasterio import mask, features, warp

    from rasterio.io import MemoryFile

    import rasterio

    import numpy as np

 

    def create_memory_file(data, west_bound, north_bound, cellsize, driver='AAIGrid'):

        #data is a numpy array

        dtype = data.dtype

        shape = data.shape

        transform = rasterio.transform.from_origin(west_bound, north_bound, cellsize, cellsize)

        memfile = MemoryFile()

        dataset = memfile.open(driver=driver, width= shape[1], height = shape[0], transform=transform, count=1, dtype = dtype)

        dataset.write(data,1)

    

        return dataset

    def close_memory_file(memfile):

        memfile.close()

    

    

    data = np.array([[1,2,3], [4,5,6], [7,8,9]])

    memfile = create_memory_file(data, 0, 2, 0.5)

    memfile.read(1)

 

The last line throws an error:

 

    Traceback (most recent call last):

      File "D:/11202750-002_RA2CE/Basis/common.py", line 214, in <module>

        memfile.read(1)

      File "rasterio\_io.pyx", line 209, in rasterio._io.DatasetReaderBase.read

    rasterio.errors.UnsupportedOperation: not readable

 

The memfile apparently only has write permissions because of the following:

 

    >>> memfile

    <open BufferedDatasetWriter name='/vsimem/3c0572dd-a295-4f2b-a65d-22a404dd5d0f.' mode='w'>

    >>> memfile.mode

    'w'

 

I have tried various combinations of adding `mode=r+`, `permissions=r+` to my `memfile.open()` call but it won't allow this.

 

How can I add the read/write mode at the level of the `open` statement?

 

 

  [1]: https://gis.stackexchange.com/questions/297562/open-a-raster-file-with-read-and-write-permissions-in-rasterio