Pre/Post Script Examples

The following pre-processing and post-processing script examples demonstrate how Aspera prepost environment variables are used to achieve different types of processing.

Note: The "File Pre- and Post-Processing (Prepost)" feature will be deprecated from HST Server and HST Endpoint in versions 4.0 and onward. At that time, customers should use Inline File validation with Lua (Inline File Validation with Lua Script) or an External URL validator (Out-of-Transfer File Validation) for pre-post processing features.

These examples use bash syntax. To run these examples on your own system, do the following:

Save the example to /opt/aspera/var/myscript.sh.
Ensure that the script file is executable -- for example:
```
$ chmod +x /opt/aspera/var/myscript.sh
```
Add the line /opt/aspera/var/myscript.sh to /opt/aspera/var/aspera-prepost to call myscript.sh.
Be sure there is no exit condition in aspera-prepost before you call your script.

Shell - Change file and directory permissions.
In the shell script, change file and directory permissions after receiving, and log into the file /tmp/p.log:
```
#!/bin/bash
if [ $TYPE == File ]; then
  if [ $STARTSTOP == Stop ]; then
    echo "The file is: $FILE" >> /tmp/p.log
    chmod 777 $FILE
  fi
fi
```

Shell - Forward files to another computer.

In the shell script, transfer received files to a third computer 10.10.10.10, and remove the local copy.

Important: For this example to work properly, the server's host key must be cached.

#!/bin/bash
TARGET=aspera@10.10.10.10:/tmp
RATE=10m
export ASPERA_SCP_PASS=aspera
if [ $TYPE == File ]; then
  if [ $STARTSTOP == Stop ]; then
    if [ $STATE == success ]; then
      if [ $DIRECTION == recv ]; then
        logger -plocal2.info "Move file $FILE to $TARGET"
        ascp -T -o RemoveAfterTransfer=yes -l $RATE $FILE $TARGET
      fi
    fi
  fi
fi

Shell - Create a log of successfully transferred files.

In the shell script, store successfully transferred files as a list into the file /tmp/aspera.transfer.log:

#!/bin/bash
if [ $TYPE == File ]; then
  if [ $STARTSTOP == Stop ]; then
    if [ $SIZE -gt 0 ]; then
      if [ `expr $SIZE - $STARTBYTE` -gt 0 ]; then
        echo `date` >> /tmp/aspera.transfer.log
        echo "$STATE $FILE $SIZE bits transferred" >> /tmp/aspera.transfer.log
      fi
    fi
  fi
fi