Python - Table not found error when using SQlite3 with Daemonize

I have a slack bot that accesses an SQlite database. When I run the bot in the foreground, everything works but when I run it as a daemon, it seems to connect to my database but then returns "table not found" on every query that I run.

The thing is, this used to work until my latest version and I can't find what changed, so I made a stripped down version as a test but I still have the same problem. See below:

import syslog
import sqlite3
import os
from daemonize import Daemonize
from slackclient import SlackClient
from qatoken import token

#Slack vars
nickname = "NetBot-QA"
dump = "#net-dump-qa"
channel = "#net-alerts-qa"
avatar = ":loader:"

#Daemonize vars
pid = "/tmp/netbot-qa.pid"
app = "net-bot-qa"
syslog.openlog('netbot', 0, syslog.LOG_LOCAL4 )

###################################################### MAIN
def main():

    sc = SlackClient(token)
    sc.api_call("chat.postMessage", username=nickname, channel=dump, text="{0}/net-alerts-test.db".format(os.path.dirname(__file__)), icon_emoji=avatar)

    try:
        conn = sqlite3.connect("{0}/net-alerts-test.db".format(os.path.dirname(__file__)))
        c = conn.cursor()
        c.execute("SELECT * from maint_calendar")
        sc.api_call("chat.postMessage", username=nickname, channel=dump, text="made it!", icon_emoji=avatar)
    except (SystemExit, KeyboardInterrupt):
        raise
    except Exception, e:
        sc.api_call("chat.postMessage", username=nickname, channel=dump, text="The bot crashed", icon_emoji=avatar)
        syslog.syslog("error: {0}".format(e))

########################################################################################
#main()
########################################################################################
#main()
daemon = Daemonize(app=app, pid=pid, action=main)
daemon.start()

If I run main(), I get the slack message "Made it!", but if I comment it out and run daemon.start() instead, I get "The bot crashed".

When I cat /var/log/messages, this is what I see:

Nov 16 09:47:37 server1 netbot: error: no such table: maint_calendar

[root@server1 net-alerts]# pwd
/opt/bots/net-alerts

[root@server1 net-alerts]# sqlite3 net-alerts-test.db
SQLite version 3.7.17 2013-05-20 00:56:22
sqlite> .schema
CREATE TABLE maint_calendar (start time, finish time, summary text, dc_tag text, provider text, CONSTRAINT start_sum PRIMARY KEY (start, summary));

I've also tried running this with a static path to the db but os.path.dirname has worked very well with every other script I use. I found another post saying you have to make the DB connection inside the Daemon context (main()) but I've been doing this from the start. I'm running out of ideas.

Solution

It seems to me, that this line:

conn = sqlite3.connect("{0}/net-alerts-test.db".format(os.path.dirname(__file__)))

Is actually connecting to two different sources, depending if you daemonize or just run main().

Just save the file to db in a global variable, which you use later. E.g.:

DB_PATH = "{0}/net-alerts-test.db".format(os.path.dirname(__file__))
...
def main():

    sc = SlackClient(token)
    sc.api_call("chat.postMessage", username=nickname, channel=dump, text="{0}/net-alerts-test.db".format(os.path.dirname(__file__)), icon_emoji=avatar)

    try:
        conn = sqlite3.connect(DB_PATH)