(Ruby) Extract Embedded Files from PDF

Demonstrates how to get information about the embedded files (if any) contained within a PDF, and shows how to extract each file.

Note: This example requires Chilkat v9.5.0.95 or greater.

Chilkat Ruby Downloads install from rubygems.org gem install chilkat or download... Ruby Library for Windows, MacOS, Linux, Alpine Linux

require 'chilkat'

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

pdf = Chilkat::CkPdf.new()

success = pdf.LoadFile("qa_data/pdf/embedded_files/my_embedded_files_test.pdf")
if (success == false)
    print pdf.lastErrorText() + "\n";
    exit
end

# Note: The embedded file functionality was added in Chilkat v9.5.0.95

# How many embedded files exist within the opened PDF?
numFiles = pdf.get_NumEmbeddedFiles()
print "Number of embedded files: " + numFiles.to_s() + "\n";

json = Chilkat::CkJsonObject.new()
json.put_EmitCompact(false)

bd = Chilkat::CkBinData.new()

# Get information about each file, and extract each to the filesystem.
i = 0
while i < numFiles

    success = pdf.GetEmbeddedFileInfo(i,json)
    if (success == false)
        print pdf.lastErrorText() + "\n";
        exit
    end

    print json.emit() + "\n";

    # Get the filename from the JSON.
    filename = "someFile.dat"

    # The filename SHOULD always be present..
    if (json.HasMember("filename") == true)
        filename = json.stringOf("filename")
    end

    # Get the file data.
    success = pdf.GetEmbeddedFileBd(i,bd)
    if (success == false)
        print pdf.lastErrorText() + "\n";
        exit
    end

    # Save the contents of the bd to the filename (in the current working directory) in the filesystem.
    success = bd.WriteFile(filename)
    if (success == false)
        print "Failed to write output file." + "\n";
    end

    i = i + 1
end

# Sample output for the above code:

# Number of embedded files: 3
# {
#   "filename": "employees.json",
#   "desc": "JSON",
#   "subType": "application/json",
#   "size": 159,
#   "creationDate": "D:20230715170506-05'00'",
#   "modDate": "D:20160207153838-05'00'"
# }
# 
# {
#   "filename": "rsaPubKey.pem",
#   "desc": "RSA Public Key PEM",
#   "size": 451,
#   "creationDate": "D:20230715170546-05'00'",
#   "modDate": "D:20150724133153-05'00'"
# }
# 
# {
#   "filename": "starfish.jpg",
#   "desc": "Starfish JPG",
#   "subType": "image/jpeg",
#   "size": 6229,
#   "creationDate": "D:20230715170356-05'00'",
#   "modDate": "D:20080529103055-05'00'"
# }