[FIXED] How to convert binary data from mongodb to string in Python properly

Issue

I have an image that is saved in mongodb as a series of bytes (see screenshot 1). As you can this string contains an apostrophe as the first symbol and the same apostrophe at the end of the string.

Then I retrieve this field in Python and encode it via base64:

@app.route("/personal_account", methods=['GET'])
def personal_account():
    # get avatar field from database
    user = list(db.users.find({"user_id": session.get("user_id")}))[0]
    return render_template("personal_account.html",
                           username = user.get("user_name"),
                           email = user.get("email"),
                           avatar = base64.b64encode(user.get("avatar")))

Then for some reason after encoding I see that first and last apostrophes have been encoded too (see screenshot 2, b'):

So I cannot parse the image into my html form because of this couple of apostrophes.

The question is: how can I get rid of this apostrophes in order to parse the image in binary format properly? Thank you in advance!

Solution

Finally I found the decision. I needed to encode bytes from mongodb to base64 first and then decode the bytestring to string.

Thanks @Carcigenicate and @0x00 for help!

Also this topic was very helpful in my case.

@app.route("/personal_account", methods=['GET'])
def personal_account():
    # get avatar field from database
    user = list(db.users.find({"user_id": session.get("user_id")}))[0]
    img_from_mongo = user.get("avatar") # <class 'bytes'>, bytestring from mongodb
    base64_bytes = base64.b64encode(img_from_mongo) # bytestring encoded in base64
    base64_str = base64_bytes.decode("utf-8") # string that is decoded from bytes object
    return render_template("personal_account.html",
                           username = user.get("user_name"),
                           email = user.get("email"),
                           bytes_line = user.get("avatar"),
                           avatar = base64_str)

Answered By - Whatever22