Unzip a ".gz" file in ColdFusion

Below is the code for ColdFusion function to unzip a ".gz" file. The code describes each logic with comment line. Hope it will not create any trouble for understanding.

<cfscript>
    function unzipGZ(inputFilePath)
    {
        var returnString = "";
        var outFileName = "";
        var outPath = GetDirectoryFromPath(inputFilePath);
        var inputFileName = getFileFromPath(arguments.inputFilePath);
        var buffer = repeatString(" ",1024).getBytes(); //Create a buffer of 1024 bytes
        
        var bufferLen = 0;
        var inStream = createObject("java", "java.io.FileInputStream");
        var outStream = createObject("java", "java.io.FileOutputStream");
        var gzInStream = createObject("java", "java.util.zip.GZIPInputStream");
        
        //OutPut File Name
        outFileName = left(inputFileName, (len(inputFileName) - 3));
        
        try{
            
            //File UnZip Operation
            inStream.init(inputFilePath);
            gzInStream.init(inStream);
            outStream.init(outPath & outFileName);
            
            //Read the file stream into buffer and write into out put file
            do{
                bufferLen = gzInStream.read(buffer, 0, 1024);
                if( bufferLen != -1 )
                    outStream.write(buffer, 0, bufferLen);
            } while(bufferLen != -1);
            
            //Store the OutPut File Path in the function return string
            returnString = outPath & outFileName;
        } catch(Any e){
            WriteDump(e);abort;
            
            //Store the error message in the return string
            returnString = e.message & "Details: #e.Detail#";
        } finally{
            try{
                //Close all Opened file Streams
                outStream.close();
                gzInStream.close();
                inStream.close();
            }catch(Any e){}
        }
        
        return returnString;
    }
    
   request.fileAfterUnZip = unzipGZ("D:\YMLDP_Data\Temp\listings-leaserental.txt.gz");
   WriteDump(request.fileAfterUnZip);
</cfscript>

Filtering CFZIP file extraction Operation

To extract a zip file in ColdFusion we have a wonderful tag "cfzip". By, using which we can list the files available in that zip or we can give password for password encrypted zip  to extract all files.

Sometimes we need to extract only 1/2 files from the zip bundles then how can we extract only the required files using cfzip.

<cfzip action="unzip" file="#local.inFilePath#" destination="#local.outputPath#" recurse="true" filter="#local.fileList.name#" overwrite="true">
 </cfzip>

file: Takes the input zip file.
destination: It's the destination directory in which you want to extract the files.
recurse: Specifies whether action applies to sub directories in the zip bundle.
overwrite: If a file exists with the same name in the destination directory then it will overwrite.
filter:Filter the files which you need to extract.

Case 1: Extract All text files from the zip bundle

filter = "*.txt";

Case 2: Extract a specific file(xyz.jpg) from the zip bundle 

filter = "xyz.jpg";

Case 3: Extract all files whose file name contains string "listing"

filter = "*listing*.txt"

Case 4: Extract more than one files with specific file names

filter = "abc.txt|xyz.txt". It will extract only abc.txt and xyz.txt


The filter is applicable to the following actions of "cfzip"

1. delete
2. list
3. unzip
4. zip

Hope it will help you...