I am trying and failing to read a local .accdb file in my Python 3.11 app, which is running in an python:3.11-alpine
container.
My Dockerfile executes without errors:
FROM python:3.11-alpine
EXPOSE 5001
ENV PYTHONDONTWRITEBYTECODE=1
ENV PYTHONUNBUFFERED=1
RUN apk update && apk add --no-cache gcc g++ musl-dev unixodbc-dev flex bison gawk
COPY requirements.txt .
RUN python -m pip install -r requirements.txt
RUN apk add --no-cache git autoconf automake libtool gettext-dev make
RUN git clone https://github.com/mdbtools/mdbtools.git
WORKDIR /mdbtools
RUN autoreconf -i -f
RUN ./configure --with-unixodbc=/usr --disable-dependency-tracking
RUN make
RUN make install
RUN echo -e "n[MDBTools]nDescription=MDBTools DrivernDriver=/usr/local/lib/odbc/libmdbodbc.so" >> /etc/odbcinst.ini
RUN apk add --no-cache nano
WORKDIR /app
COPY . /app
RUN adduser -u 5678 --disabled-password --gecos "" appuser && chown -R appuser /app
USER appuser
CMD ["python", "server.py"]
My Python script (accdb_test.py
):
import pyodbc
import argparse
parser = argparse.ArgumentParser(description='Connect to an Access database.')
parser.add_argument('db_path', type=str, help='The path to the Access database')
args = parser.parse_args()
conn_str = (
r'DRIVER={MDBTools};'
r'DBQ=' + args.db_path + ';'
)
try:
conn = pyodbc.connect(conn_str)
print("Connection successful!")
except pyodbc.Error as e:
print("Failed to connect to the database:", e)
I build the container connect to its terminal, than I run the script with this result:
/app $ python accdb_test.py /app/input_examples/caesar/MODEL_13-16_R01.ACCDB
['MDBTools']
File not found
File not found
Unable to locate database
Failed to connect to the database: ('HY000', 'The driver did not supply an error!')
The path to the .accdb
file is correct, I checked:
/app $ ls -l /app/input_examples/caesar/MODEL_13-16_R01.ACCDB
-rwxrwxrwx 1 appuser root 47116288 Mar 18 09:29 /app/input_examples/caesar/MODEL_13-16_R01.ACCDB
2
Answers
As far as I can tell, mdbtools expects a 2-component connection string, with only a single semicolon.
Since you end your connection string with a semicolon, it is looking for a file named
/app/input_examples/caesar/MODEL_13-16_R01.ACCDB;
and cannot find that file.This can be seen here in the source, it’s splitting the connection string into a maximum of 2 components, where any further separators and components get added to the file name.
The fix is simple: remove the semicolon:
The way mdbtools is being built in the original Dockerfile causes the
g_strsplit()
function (used here) to malfunction. The following Dockerfile allowsg_strsplit()
to work correctly and the.connect()
will not fail whenDBQ=
has a trailing semicolon.