extract variable's value from script file in Install Anywhere - linux

Question

I am using Install Anywhere 2012 and would like to be able to parse a batch or shell script for a give value and have that value stored in an IA variable. For instance, if I have the following shell file:
MY_VAR1=123
MY_VAR2=a\b\c
ECHO $MY_VAR1
I would like to pass in the path to the file and the variable name (ex. MY_VAR1) and have the result, 123, stored in an IA variable of my choosing (lets say $OUTPUT$). I could achieve this through writing some java custom code but was wondering if there was an alternative approach built into IA that would make this much easier. The variable will not be initialized when I need to figure out its value so essentially just echoing it's value or something similar will not work. Any help would be greatly appreciated!

Answer 1

example in Windows batch:
#echo off &setlocal
for /f "tokens=2delims==" %%a in ('findstr "MY_VAR1" "ShellFile"') do set "output=%%a"
if defined output (echo MY_VAR1: %output%) else echo MY_VAR1 not found!

Answer 2

On Linux/Unix, you could use perl or awk (both are standard utilities in most distros). Python or Ruby are also candidates, but may not be installed on your target system. You could even write your own targeted parser using Lex and Yacc and ship it with your installer. However, for your needs, that's surely overkill.
Here's an example of a possible awk solution in an Execute Script/Batch File Action:
#!/bin/bash
awk '
# Process lines that begin with our variable name,
# preceded by optional spaces or tabs.
/^[ \t]*$TARGET_VARIABLE_NAME$=.+/ {
# Split the current line on "=" into
# an array called result
split($0, result, "=")
value = result[1]
# Look for trailing comments and remove them.
offset = index(value, "#")
if (offset > 0) {
value = substr(value, 1, offset - 1)
}
# Remove any possible leading spaces and quotes.
# Note that the single-quote is escaped. That escape
# is for bash, not for awk. I am doing this from
# memory and do not have access to IA right now.
# you may have to play with the escaping.
gsub(/^[\'" ]*/, "", value)
# Remove any possible trailing spaces and quotes.
# See above regarding the escaped single-quote.
gsub(/[\'" ]*$/, "", value)
# send "value" to stdout
print value
}
' < $SHELL_INPUT_FILE$
The print value line (near the end) sends value to stdout.
In the Execute Script/Batch File Action settings you can designate variables that receive the stdout and stderr streams produced by the script action. By default, the stdout stream is stored in $EXECUTE_STDOUT$. You can change this to a variable name of your choosing.
In the example, above, $TARGET_VARIABLE_NAME$ and $SHELL_INPUT_FILE$ are InstallAnywhere variables that hold the name of the variable to find and the name of the file to parse, respectively. These variables will be replaced by their values before the Action executes.
Assume we have a script called /home/fred/hello.sh, which contains the following code:
#!/bin/bash
WIFE='Wilma'
NEIGHBOR="Barney Rubble"
echo "Hello to $WIFE and $NEIGHBOR from $PWD"
Before the Execute Script/Batch File Action runs, stuff the name of the script file into $SHELL_INPUT_FILE$ (/home/fred/hello.sh). Then set the value of $TARGET_VARIABLE_NAME$ to the variable you wish to find (say, NEIGHBOR). After the action completes, $EXECUTE_STDOUT$ in InstallAnywhere will contain Barney Rubble.
You can build on this idea to parse arbitrarily complex files in an Execute Script/Batch File Action. Just make your awk (or perl/Ruby/Python) script as complex as needed.
NOTE: when scripting Unix shell scripts in InstallAnywhere ALWAYS check the "Do not replace unknown variables" option. If you don't, InstallAnywhere will quietly convert anything that looks vaguely like an InstallAnywhere variable into blanks... It's very annoying.
For a Windows solution, find a standalone Windows version of awk or perl and include it with your installation. Then extend the above solution to work for batch files.
You'd want to create two Execute Script/Batch File Actions, one with a rule for Linux/Unix and one with a rule for Windows. You'd have to install the Windows awk or perl executable before calling this action though. Also, you'd need to fully qualify the path to the awk/perl executable. Finally, the actual script will need to be sensitive to differences in batch syntax versus shell syntax.
Below is an awk script modified to look for batch variable definitions. The pattern changes and you won't have to worry about embedded comments:
$PATH_TO_AWK_EXE$ '
# This pattern looks for optional spaces, the word SET
# with any capitalization, the target variable, more
# optional spaces and the equals sign.
/^[ \t]*[Ss][Ee][Tt][ \t]*$TARGET_VARIABLE_NAME$[ \t]*=.+/ {
# Split the current line on "=" into
# an array called result
split($0, result, "=")
value = result[1]
# No trailing comments in Batch files.
# Remove any possible leading spaces and quotes.
# Note that the single-quote is escaped. That escape
# is for bash, not for awk. I am doing this from
# memory and do not have access to IA right now.
# you may have to play with the escaping.
gsub(/^[\'" ]*/, "", value)
# Remove any possible trailing spaces and quotes.
# See above regarding the escaped single-quote.
gsub(/[\'" ]*$/, "", value)
# send "value" to stdout
print value
}
' < $SHELL_INPUT_FILE$
Above, the IA variable $PATH_TO_AWK_EXE$ points to the location where awk was installed. It would be set as some combination of $USER_INSTALL_FOLDER$, possibly other directory names, and the name of the awk.exe file. $PATH_TO_AWK_EXE$ can later be used to remove the awk executable, if desired.

Answer 3

You can try to get variable from output of script
"Execute Script" -> Store process's stdout in: $EXECUTE_OUTPUT$
Than you can use $EXECUTE_OUTPUT$ as variable after that