Tips on good practice in my bash script that logs in to a website, downloads a PDF, adds it to iBooks and uploads it to dropbox

Question

I am running a scheduled script on my iPhone that logs in to a website, downloads a PDF, adds it to iBooks and uploads it to dropbox. All of this happens only when it has WiFi access.

I want to make it as error proof as possible. So I am open for criticism and tipps since it is my first bash script.

#!/bin/sh


DATE=$(date "+%Y%m%d")
DATE_LOCALE=$(date "+%d.%m.%Y")
#LOGDATE=$(date "+%F %T")
DOMAIN=http://url.to.site
DOMAIN_LOGOUT=http://url.to.site/logout
URL1=http://url.to.site/issuefiles/
URL2=_paper/pdfs/paper
URL3=_complete.pdf
url=$URL1$DATE$URL2$DATE$URL3
FILENAME="/path/paper"$DATE"_complete.pdf"
ITEMNAME="paper"$DATE"_complete"
COOKIEFILE=/path/cookie.txt
ICONFILE=/path/title.jpg
INFOFILE=/path/Info.plist
USERAGENT="Mozilla/5.0 (compatible; MSIE 7.01; Windows NT 5.0)"
IP_ADDRESS=$(ifconfig en0 | grep inet | cut -d: -f2 | awk '{ print $2}')
IP_ADDR_VAL=$(echo "$IP_ADDRESS" | grep -Ec '^(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9])\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0)\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0)\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[0-9])')



if [ $IP_ADDR_VAL -eq 1 ]; then

  #Get the title image for the app icon
  cd /path
  wget http://path.to.site/title.jpg >/dev/null 2>&1

  #Debug last command
  if [ $? == 0 ]
  then 
    echo $(date "+%F %T") : wget successful
  else
    echo $(date "+%F %T") : wget not successful
  fi

  #Check if downloaded correctly
  if [ -e "$ICONFILE" ]
  then 
    echo $(date "+%F %T") : title.jpg downloaded
  else
    echo $(date "+%F %T") : title.jpg not downloaded
  fi

  #Get token
  TOKEN=$(curl -A "$USERAGENT" --cookie $COOKIEFILE --cookie-jar $COOKIEFILE http://url.to.site/ | grep "token" | sed -e 's/<input type=\"hidden\" name=\"token\" value=\"//' | sed -e 's/\" \/>//' )
  curl -A "$USERAGENT" --data-urlencode "username=myuser" --data-urlencode "password=mypassword" --data-urlencode "token="$TOKEN --cookie $COOKIEFILE $DOMAIN  >/dev/null 2>&1

  #Debug last command
  if [ $? == 0 ]
  then 
    echo $(date "+%F %T") : curl for token successful 
  else
    echo $(date "+%F %T") : curl for token not successful 
  fi

  #Download of epaper file
  curl -A "$USERAGENT" -L --progress-bar -o $FILENAME --cookie $COOKIEFILE $url 


  #Debug last command
  if [ $? == 0 ]
  then 
    echo $(date "+%F %T") : curl for Download of pdf successfull
  else
    echo $(date "+%F %T") : curl for Download of pdf successfull
  fi


  #logout
  LTOKEN=$(curl -A "$USERAGENT" --cookie $COOKIEFILE --cookie-jar $COOKIEFILE $DOMAIN | grep "ltoken" | sed "s/.* value=\"\(.*\)\".*/\1/")
  curl -A "$USERAGENT" --data-urlencode "ltoken="$LTOKEN --cookie $COOKIEFILE $DOMAIN_LOGOUT

  #delete cookiefile
  if [ -e "$COOKIEFILE" ]
  then
     rm $COOKIEFILE
     #Debug last command
     if [ $? == 0 ]
     then 
        echo $(date "+%F %T") : Cookie file deleted
     else
        echo $(date "+%F %T") : Cookie file not deleted
     fi
  fi

  #if file exists
  if [ -e "$FILENAME" ]
  then
    #If downloaded file exeeds 1MB it should have been a success
    #fsize=$(stat -c %s $FILENAME)
    #echo $fsize
    if [ $(stat --format="%s" "$FILENAME") -gt 1000000 ]; then
        #import to iBooks and add to newsstand
        cd /private/var/mobile/Media/Books/Purchases/
        echo $(date "+%F %T") : $(python /path/ibooks.py import $FILENAME)
        md5=($(md5sum $FILENAME))
        appdir=/private/var/stash/Applications/$md5.app

        if [ ! -e "$appdir" ]
        then    
            mkdir $appdir
            if [ -e "$ICONFILE" ]
            then
                cp $ICONFILE $appdir/Icon.png
                rm $ICONFILE
            else 
                echo $(date "+%F %T") : Error. No Iconfile available.
            fi          
            cd /path
            python parse.py $ITEMNAME $md5
            if [ -e "$INFOFILE" ]
            then
                cp $INFOFILE $appdir
                rm $INFOFILE
            else
                echo $(date "+%F %T") : Error. No Info file available
            fi  
        else
            echo $(date "+%F %T") : Appdirectory alsready exists!
        fi
        #Upload to dropbox
        echo $(date "+%F %T") : Uploading to Dropbox... 
        cd /path
        ./dropbox_uploader.sh upload $FILENAME "/DestPathOnDropbox/"$ITEMNAME".pdf"

         #Debug last command
         if [ $? == 0 ]
         then 
            echo $(date "+%F %T") : Upload to Dropbox successful!
          #curl -k -s $PROWL_URL >/dev/null 2>&1
         else
            echo $(date "+%F %T") : Upload to Dropbox not successful!
         fi


        rm $FILENAME
    else
    #Filesoize too small. Delete download
    echo $(date "+%F %T") : Filesize too small. Expected more!
    rm $FILENAME
    fi
  fi

  #Delete title.jpg
  if [ -e /path/title.jpg ]
  then
    rm /path/title.jpg
  fi

  echo $(date "+%F %T") : Done!!

else
  echo $(date "+%F %T") : No WiFi!  Aborted...
fi

Answer 1

I don't have time to look through everything, but here's some low-hanging fruit:

if [ -e /path/title.jpg ]
then
    rm /path/title.jpg
fi

can be reduced to:

rm -f /path/title.jpg

Because man rm says about -f:

ignore nonexistent files and arguments, never prompt

EDIT: Another thing. Instead of

some_command arg1 arg2 arg3

if [ $? == 0 ]
then
    ...

You can just say:

if some_command arg1 arg2 arg3
then
    ...