GroupDocs.Signature for .NET 19.5 Release Notes

Major Features

There are few new features, improvements and bug fixes in this regular release. Most features are related to support of djvu format for most service methods, implementation of serialization and encryption of custom data objects into Metadata signatures with ability to extract them back and specify custom serialization and data encryption. Also this release contains some internal security and licensing improvements.

  • Introduced ability to embed custom objects to Metadata Signature for Cells and Words Documents
  • Implemented support to embed custom objects to Metadata Signature for Slides Presentation Documents
  • Added support of custom serialization for Pdf Metadata Signature object
  • Implemented ability of custom data encryption and decryption for embedded objects into Metadata Signature for Pdf Documents
  • Internal improvements of error handling and code updates
  • Fixed data serialization issues with simple data type for QR and Metadata signature

Full List of Issues Covering all Changes in this Release

KeySummaryIssue Type
SIGNATURENET-2020Fix exception for de-serialization of encrypted string values in Metadata SignaturesBug
SIGNATURENET-2012SaveOptions.OutputFileName doesn’t affect on result name of signed documentBug
SIGNATURENET-2008PdfQRCodeSignature.GetData() throws exceptionBug
SIGNATURENET-2024Implement ability to embed custom object to Slides Metadata SignatureNew Feature
SIGNATURENET-1842Implement ability to embed custom object to Words Metadata SignatureNew Feature
SIGNATURENET-1838Implement ability to embed custom object to Cells Metadata SignatureNew Feature
SIGNATURENET-2014Implement support of .djvu file format for verification processImprovement
SIGNATURENET-2013Implement ability to search files with .djvu format as image documentsImprovement
SIGNATURENET-2007Implement ability to sign files with .djvu format as image documentsImprovement
SIGNATURENET-1980Implement new method AddSignature for MetadataOptionsImprovement

Public API and Backward Incompatible Changes

  1. GroupDocs.Signature.Options.WordsMetadataSignOptions
    Public class WordsMetadataSignOptions was extended with new public method AddSignature. Method creates new Words Metadata Signature with passed arguments (name and value), adds signature to list of metadata signatures and returns newly created object as result.

    AddSignature method

    /// <summary>
    /// Creates new WordsMetadataSignature with passed arguments and adds it to collection.
    /// </summary>
    /// <param name="name">The name of new metadata signature</param>
    /// <param name="value">The value of new metadata signature</param>
    /// <returns>Newly created signature that was added to MetadataSignatures collection</returns>
    public WordsMetadataSignature AddSignature(string name, object value)
    

    Following example demonstrates signing Words document with Metadata signature using this new method:

    Sign Document with metadata signatures

    // setup Signature configuration
    SignatureConfig signConfig = new SignatureConfig
    {
        StoragePath = @"c:\Aspose\Test\Storage",
        OutputPath = @"c:\Aspose\Test\Output"
    };
    // instantiating the signature handler
    SignatureHandler handler = new SignatureHandler(signConfig);
    // setup options with text of signature
    WordsMetadataSignOptions signOptions = new WordsMetadataSignOptions();
    // Specify different Metadata Signatures and add them to options sigature collection
    // setup Author property with encryption
    var msAuth = signOptions.AddSignature("Author", "Mr.Scherlock Holmes");
    msAuth.DataEncryption = new SymmetricEncryption(SymmetricAlgorithmType.Rijndael, "12345", "12345");
    // setup data of document id
    signOptions.AddSignature("DocumentId", Guid.NewGuid().ToString());
    // setup data of sign date
    var msDate = signOptions.AddSignature("SignDate", DateTime.Now);
    msDate.Value = DateTime.Now.Date;
    // setup some integer value
    signOptions.AddSignature("DocDays", 12345);
    // setup data of sign date
    signOptions.AddSignature("SignKoeff", 2.345M);
    // sign document
    string signedPath = handler.Sign<string>("test.docx", signOptions,
        new SaveOptions { OutputType = OutputType.String, OutputFileName = "SignedMetadata" });
    Console.WriteLine("Signed file path is: " + signedPath);
    
  2. GroupDocs.Signature.Options.SlidesMetadataSignOptions
    Public class SlidesMetadataSignOptions was extended with new public method AddSignature. Method creates new Slides Metadata Signature with passed arguments (name and value), adds signature to list of metadata signatures and returns newly created object as result.

    AddSignature method

    /// <summary>
    /// Creates new SlidesMetadataSignature with passed arguments and adds it to collection.
    /// </summary>
    /// <param name="name">The name of new metadata signature</param>
    /// <param name="value">The value of new metadata signature</param>
    /// <returns>Newly created signature that was added to MetadataSignatures collection</returns>
    public SlidesMetadataSignature AddSignature(string name, object value)
    

    Following example demonstrates signing Slides document with Metadata signature using this new method:

    // setup Signature configuration
    SignatureConfig signConfig = new SignatureConfig
    {
        StoragePath = @"c:\Aspose\Test\Storage",
        OutputPath = @"c:\Aspose\Test\Output"
    };
    // instantiating the signature handler
    SignatureHandler handler = new SignatureHandler(signConfig);
    // setup options with text of signature
    SlidesMetadataSignOptions signOptions = new SlidesMetadataSignOptions();
    // Specify different Metadata Signatures and add them to options sigature collection
    // setup Author property with encryption
    var msAuth = signOptions.AddSignature("Author", "Mr.Scherlock Holmes");
    msAuth.DataEncryption = new SymmetricEncryption(SymmetricAlgorithmType.Rijndael, "12345", "12345");
    // setup data of document id
    signOptions.AddSignature("DocumentId", Guid.NewGuid().ToString());
    // setup data of sign date
    var msDate = signOptions.AddSignature("SignDate", DateTime.Now);
    msDate.Value = DateTime.Now.Date;
    // setup some integer value
    signOptions.AddSignature("DocDays", 12345);
    // setup data of sign date
    signOptions.AddSignature("SignKoeff", 2.345M);
    // sign document
    string signedPath = handler.Sign<string>("test.pptx", signOptions,
        new SaveOptions { OutputType = OutputType.String, OutputFileName = "SignedMetadata" });
    Console.WriteLine("Signed file path is: " + signedPath);
    
  3. GroupDocs.Signature.Options.PdfMetadataSignOptions
    Public class PdfMetadataSignOptions was extended with new public method AddSignature. Method creates new Pdf Metadata Signature with passed arguments (name and value), adds signature to list of metadata signatures and returns newly created object as result.

    AddSignature method

    /// <summary>
    /// Creates new PdfMetadataSignature with passed arguments and adds it to collection.
    /// </summary>
    /// <param name="name">The name of new metadata signature</param>
    /// <param name="value">The value of new metadata signature</param>
    /// <returns>Newly created signature that was added to MetadataSignatures collection</returns>
    public PdfMetadataSignature AddSignature(string name, object value)
    

    Following example demonstrates signing Pdf document with Metadata signature using this new method:

    // setup Signature configuration
    SignatureConfig signConfig = new SignatureConfig
    {
        StoragePath = @"c:\Aspose\Test\Storage",
        OutputPath = @"c:\Aspose\Test\Output"
    };
    // instantiating the signature handler
    SignatureHandler handler = new SignatureHandler(signConfig);
    // setup options with text of signature
    PdfMetadataSignOptions signOptions = new PdfMetadataSignOptions();
    // Specify different Metadata Signatures and add them to options sigature collection
    // setup Author property with encryption
    var msAuth = signOptions.AddSignature("Author", "Mr.Scherlock Holmes");
    msAuth.DataEncryption = new SymmetricEncryption(SymmetricAlgorithmType.Rijndael, "12345", "12345");
    // setup data of document id
    signOptions.AddSignature("DocumentId", Guid.NewGuid().ToString());
    // setup data of sign date
    var msDate = signOptions.AddSignature("SignDate", DateTime.Now);
    msDate.Value = DateTime.Now.Date;
    // setup some integer value
    signOptions.AddSignature("DocDays", 12345);
    // setup data of sign date
    signOptions.AddSignature("SignKoeff", 2.345M);
    // sign document
    string signedPath = handler.Sign<string>("test.pdf", signOptions,
        new SaveOptions { OutputType = OutputType.String, OutputFileName = "SignedMetadata" });
    Console.WriteLine("Signed file path is: " + signedPath);
    
  4. GroupDocs.Signature.Options.CellsMetadataSignOptions
    Public class CellsMetadataSignOptions was extended with new public method AddSignature. Method creates new Cells Metadata Signature with passed arguments (name and value), adds signature to list of metadata signatures and returns newly created object as result.

    AddSignature method

    /// <summary>
    /// Creates new CellsMetadataSignature with passed arguments and adds it to collection.
    /// </summary>
    /// <param name="name">The name of new metadata signature</param>
    /// <param name="value">The value of new metadata signature</param>
    /// <returns>Newly created signature that was added to MetadataSignatures collection</returns>
    public CellsMetadataSignature AddSignature(string name, object value)
    

    Following example demonstrates signing Cells document with Metadata signature using this new method:

    // setup Signature configuration
    SignatureConfig signConfig = new SignatureConfig
    {
        StoragePath = @"c:\Aspose\Test\Storage",
        OutputPath = @"c:\Aspose\Test\Output"
    };
    // instantiating the signature handler
    SignatureHandler handler = new SignatureHandler(signConfig);
    // setup options with text of signature
    CellsMetadataSignOptions signOptions = new CellsMetadataSignOptions();
    // Specify different Metadata Signatures and add them to options sigature collection
    // setup Author property with encryption
    var msAuth = signOptions.AddSignature("Author", "Mr.Scherlock Holmes");
    msAuth.DataEncryption = new SymmetricEncryption(SymmetricAlgorithmType.Rijndael, "12345", "12345");
    // setup data of document id
    signOptions.AddSignature("DocumentId", Guid.NewGuid().ToString());
    // setup data of sign date
    var msDate = signOptions.AddSignature("SignDate", DateTime.Now);
    msDate.Value = DateTime.Now.Date;
    // setup some integer value
    signOptions.AddSignature("DocDays", 12345);
    // setup data of sign date
    signOptions.AddSignature("SignKoeff", 2.345M);
    // sign document
    string signedPath = handler.Sign<string>("test.xlsx", signOptions,
        new SaveOptions { OutputType = OutputType.String, OutputFileName = "SignedMetadata" });
    Console.WriteLine("Signed file path is: " + signedPath);
    
  5. Public classes CellsMetadataSignature, SlidesMetadataSignature, WordsMetadataSignature were extended with new public property DataEncryption of type IDataEncryption

    DataEncryption property

    /// <summary>
    /// Gets or sets implementation of <see cref="IDataEncryption"/> interface to encode and decode signature Value property.
    /// </summary>
    public IDataEncryption DataEncryption { get; set; }
    

    and overloaded method public T GetData(). These methods return object of type T over de-serialization and decryption from Metadata Value.

    GetData() method

    /// <summary>
    /// Obtain object from Metadata Signature Value over de-serialization and decryption
    /// </summary>
    /// <typeparam name="T">Type of object to deserialize from Metadata value</typeparam>
    /// <returns></returns>
    public T GetData<T>() where T : class
         
    /// <summary>
    /// Obtain object from Metadata Signature Value over deserialization.
    /// </summary>
    /// <typeparam name="T">Type of object to deserialize from Metadata Value</typeparam>
    /// <param name="dataEncryption">Set custom data encryption implementation</param>
    /// <returns></returns>
    public T GetData<T>(IDataEncryption dataEncryption) where T : class 
    

    Custom data class DocumentSignature

    Example of custom class

    public class DocumentSignature
    {
        // specify SkipSerialization attribute to skip this field on serialization
        [SkipSerialization]
        public string Version { get; set; }
        // specify SkipSerialization attribute to skip this field on serialization
        [SkipSerialization]
        public bool IsProcessed { get; set; }
        [Format("SignatureID")]
        public string ID { get; set; }
        [Format("Author")]
        public string Author { get; set; }
        [Format("SignatureDate","yyyy-MM-dd")]
        public DateTime Signed { get; set; }
        [Format("Factor", "N2")]
        public decimal DataFactor { get; set; }
    }
    

    Following example demonstrates signing Words document with Metadata signature with value of custom class DocumentSignature object:

    Sign Words Document with custom objects in Metadata

    // setup key and passphrase
    string key = "1234567890";
    string salt = "1234567890";
    // create data encryption
    IDataEncryption encryption = new SymmetricEncryption(SymmetricAlgorithmType.Rijndael, key, salt);
    // setup Signature configuration
    SignatureConfig signConfig = new SignatureConfig
    {
        StoragePath = @"c:\Aspose\Test\Storage",
        OutputPath = @"c:\Aspose\Test\Output"
    };
    // instantiating the signature handler
    SignatureHandler handler = new SignatureHandler(signConfig);
    // setup options with text of signature
    WordsMetadataSignOptions signOptions = new WordsMetadataSignOptions();
    // create custom object
    DocumentSignature signature = new DocumentSignature()
    {
        ID = Guid.NewGuid().ToString(),
        Author = Environment.UserName,
        Signed = DateTime.Now,
        DataFactor = 11.22M
    };
    // Specify different Metadata Signatures and add them to options sigature collection
    // setup Author property
    WordsMetadataSignature mdDocument = signOptions.AddSignature("DocumentSignature", signature);
    // set encryption
    mdDocument.DataEncryption = encryption;
    // sign document
    string signedPath = handler.Sign<string>("test.docx", signOptions,
        new SaveOptions { OutputType = OutputType.String, OutputFileName = "SignedMedataDataEncrypted.docx" });
    Console.WriteLine("Signed file path is: " + signedPath);
    

    Example how to retrieve signed Words document file with DocumentSignature Metadata Value (see examples above how to sign Document with custom data objects)

    Search custom object in Metadata

    // setup key and pasphrase
    string key = "1234567890";
    string salt = "1234567890";
    // create data encryption
    IDataEncryption encryption = new SymmetricEncryption(SymmetricAlgorithmType.Rijndael, key, salt);
    // setup Signature configuration
    SignatureConfig signConfig = new SignatureConfig
    {
        StoragePath = @"c:\Aspose\Test\Storage",
        OutputPath = @"c:\Aspose\Test\Output"
    };
    // instantiating the signature handler
    SignatureHandler handler = new SignatureHandler(signConfig);
    // setup search options
    WordsSearchMetadataOptions searchOptions = new WordsSearchMetadataOptions();
    // search document
    SearchResult result = handler.Search("SignedMedataDataEncrypted.docx", searchOptions);
    // output signatures
    List<WordsMetadataSignature> signatures = result.ToList<WordsMetadataSignature>();
    foreach (WordsMetadataSignature signature in signatures)
    {
        if (signature != null && signature.Name.Equals("DocumentSignature"))
        {
            DocumentSignature docSignature = signature.GetData<DocumentSignature>(encryption);
            if (docSignature != null)
            {
                Console.WriteLine("Found DocumentSignature signature: #{0}. Author {1} from {2}. Factor: {3}", 
                       docSignature.ID, docSignature.Author, docSignature.DataFactor, docSignature.DataFactor);
            }
        }
    }
    

    Following example demonstrates signing Cells document with Metadata signature with value of  DocumentSignature object:

    Sign Cells Document with custom objects in Metadata

    // setup key and passphrase
    string key = "1234567890";
    string salt = "1234567890";
    // create data encryption
    IDataEncryption encryption = new SymmetricEncryption(SymmetricAlgorithmType.Rijndael, key, salt);
    // setup Signature configuration
    SignatureConfig signConfig = new SignatureConfig
    {
        StoragePath = @"c:\Aspose\Test\Storage",
        OutputPath = @"c:\Aspose\Test\Output"
    };
    // instantiating the signature handler
    SignatureHandler handler = new SignatureHandler(signConfig);
    // setup options with text of signature
    CellsMetadataSignOptions signOptions = new CellsMetadataSignOptions();
    // create custom object
    DocumentSignature signature = new DocumentSignature()
    {
        ID = Guid.NewGuid().ToString(),
        Author = Environment.UserName,
        Signed = DateTime.Now,
        DataFactor = 11.22M
    };
    // Specify different Metadata Signatures and add them to options sigature collection
    // setup Author property
    CellsMetadataSignature mdDocument = signOptions.AddSignature("DocumentSignature", signature);
    // set encryption
    mdDocument.DataEncryption = encryption;
         
    // sign document
    string signedPath = handler.Sign<string>("test.xlsx", signOptions,
        new SaveOptions { OutputType = OutputType.String, OutputFileName = "SignedMedataDataEncrypted.xlsx" });
    Console.WriteLine("Signed file path is: " + signedPath);
    

    Example how to retrieve signed Cells document file with DocumentSignature Metadata Value (see examples above how to sign Document with custom data objects)

    Search custom object in Metadata

    // setup key and pasphrase
    string key = "1234567890";
    string salt = "1234567890";
    // create data encryption
    IDataEncryption encryption = new SymmetricEncryption(SymmetricAlgorithmType.Rijndael, key, salt);
    // setup Signature configuration
    SignatureConfig signConfig = new SignatureConfig
    {
        StoragePath = @"c:\Aspose\Test\Storage",
        OutputPath = @"c:\Aspose\Test\Output"
    };
    // instantiating the signature handler
    SignatureHandler handler = new SignatureHandler(signConfig);
    // setup search options
    CellsSearchMetadataOptions searchOptions = new CellsSearchMetadataOptions();
    // search document
    SearchResult result = handler.Search("SignedMedataDataEncrypted.xlsx", searchOptions);
    // output signatures
    List<CellsMetadataSignature> signatures = result.ToList<CellsMetadataSignature>();
    foreach (CellsMetadataSignature signature in signatures)
    {
        if (signature != null && signature.Name.Equals("DocumentSignature"))
        {
            DocumentSignature docSignature = signature.GetData<DocumentSignature>(encryption);
            if (docSignature != null)
            {
                Console.WriteLine("Found DocumentSignature signature: #{0}. Author {1} from {2}. Factor: {3}",
                    docSignature.ID, docSignature.Author, docSignature.DataFactor, docSignature.DataFactor);
            }
        }
    }
    

    Following example demonstrates signing Slides document with Metadata signature with value of  DocumentSignature object:

    Sign Cells Document with custom objects in Metadata

    // setup key and passphrase
    string key = "1234567890";
    string salt = "1234567890";
    // create data encryption
    IDataEncryption encryption = new SymmetricEncryption(SymmetricAlgorithmType.Rijndael, key, salt);
    // setup Signature configuration
    SignatureConfig signConfig = new SignatureConfig
    {
        StoragePath = @"c:\Aspose\Test\Storage",
        OutputPath = @"c:\Aspose\Test\Output"
    };
    // instantiating the signature handler
    SignatureHandler handler = new SignatureHandler(signConfig);
    // setup options with text of signature
    SlidesMetadataSignOptions signOptions = new SlidesMetadataSignOptions();
    // create custom object
    DocumentSignature signature = new DocumentSignature()
    {
        ID = Guid.NewGuid().ToString(),
        Author = Environment.UserName,
        Signed = DateTime.Now,
        DataFactor = 11.22M
    };
    // Specify different Metadata Signatures and add them to options sigature collection
    // setup Author property
    SlidesMetadataSignature mdDocument = signOptions.AddSignature("DocumentSignature", signature);
    // set encryption
    mdDocument.DataEncryption = encryption;
         
    // sign document
    string signedPath = handler.Sign<string>("test.pptx", signOptions,
        new SaveOptions { OutputType = OutputType.String, OutputFileName = "SignedMedataDataEncrypted.pptx" });
    Console.WriteLine("Signed file path is: " + signedPath);
    

    Example how to retrieve signed Slides document file with DocumentSignature Metadata Value (see examples above how to sign Document with custom data objects)

    Search custom object in Metadata

    // setup key and pasphrase
    string key = "1234567890";
    string salt = "1234567890";
    // create data encryption
    IDataEncryption encryption = new SymmetricEncryption(SymmetricAlgorithmType.Rijndael, key, salt);
    // setup Signature configuration
    SignatureConfig signConfig = new SignatureConfig
    {
        StoragePath = @"c:\Aspose\Test\Storage",
        OutputPath = @"c:\Aspose\Test\Output"
    };
    // instantiating the signature handler
    SignatureHandler handler = new SignatureHandler(signConfig);
    // setup search options
    SlidesSearchMetadataOptions searchOptions = new SlidesSearchMetadataOptions();
    // search document
    SearchResult result = handler.Search("SignedMedataDataEncrypted.pptx", searchOptions);
    // output signatures
    List<SlidesMetadataSignature> signatures = result.ToList<SlidesMetadataSignature>();
    foreach (SlidesMetadataSignature signature in signatures)
    {
        if (signature != null && signature.Name.Equals("DocumentSignature"))
        {
            DocumentSignature docSignature = signature.GetData<DocumentSignature>(encryption);
            if (docSignature != null)
            {
                Console.WriteLine("Found DocumentSignature signature: #{0}. Author {1} from {2}. Factor: {3}",
                    docSignature.ID, docSignature.Author, docSignature.DataFactor, docSignature.DataFactor);
            }
        }
    }