Extract attachments from a file geodatabase

extractattachments.py

"""Extracts attachments from a file geodatabase.
"""
import os, re
from os.path import join, exists
from arcpy import da

def extract_attachments(gdb, attachment_dir="images"):
    """Extract attachments from a geodatabase to the filesystem.
    """
    attach_table_name_re = re.compile(r"^\w+(?=__ATTACH$)", re.IGNORECASE)

    if not exists(attachment_dir):
        os.mkdir(attachment_dir)
    
    for dirpath, dirnames, filenames in da.Walk(gdb, datatype="Table"):
        for table in filenames:
            # Skip tables that don't end with "__ATTACH"
            match = attach_table_name_re.match(table)
            if not match:
                continue
    
            imgsubdir = join(attachment_dir, match.group(0))
            # Create the image subdirectory if it does not already exist
            if not exists(imgsubdir):
                os.mkdir(imgsubdir)
    
            fields = ["DATA", "ATT_NAME", "REL_OBJECTID", "CONTENT_TYPE", "DATA_SIZE"]
    
            table_path = join(dirpath, table)
    
            with da.SearchCursor(table_path, fields) as cursor:
                for row in cursor:
                    memview = row[0] #BLOB fields are returned as memoryview objects.
                    attname = row[1] #This is the filename of the attachment.
                    oid = row[2] # The OBJECTID of the feature associated with the attachment.
                    # Create the path that the image will be written to
                    oiddir = join(imgsubdir, str(oid)) 
                    # Create the directory if it does not already exist
                    if not exists(oiddir):
                        os.mkdir(oiddir)
                    # Create the image path.
                    imgpath = join(oiddir, attname)
                    # Write the attachment to the filesystem.
                    open(imgpath, "wb").write(memview.tobytes())
    return attach_table_name_re, dirnames, dirpath, filenames

if __name__ == '__main__':
    # Specify path to geodatabase containing images.
    gdb = "./WildlifeHabConn.gdb"

    # Specify the directory that will contain the output images.
    imgdir = "images"

    attach_table_name_re, dirnames, dirpath, filenames = extract_attachments(gdb, imgdir)