Completes #50

added support for Metadata.

Author: Jaben

lib/Domain/Builders/Faceted/HtmlConversionBehaviorBuilder.cs

@@ -102,6 +102,35 @@ public HtmlConversionBehaviorBuilder AddAdditionalHeaders(JObject extraHeaders)
         return this;
     }
 
+    /// <summary>
+    /// Sets the document metadata.
+    /// Not all metadata are writable. Consider taking a look at https://exiftool.org/TagNames/XMP.html#pdf for an (exhaustive?) list of available metadata.
+    /// </summary>
+    /// <param name="dictionary"></param>
+    /// <returns></returns>
+    public HtmlConversionBehaviorBuilder SetMetadata(IDictionary<string, object> dictionary)
+    {
+        SetMetadata(new JObject(dictionary));
+
+        return this;
+    }
+
+    /// <summary>
+    /// Sets the document metadata.
+    /// Not all metadata are writable. Consider taking a look at https://exiftool.org/TagNames/XMP.html#pdf for an (exhaustive?) list of available metadata.
+    /// </summary>
+    /// <param name="metadata"></param>
+    /// <returns></returns>
+
+    public HtmlConversionBehaviorBuilder SetMetadata(JObject metadata)
+    {
+        if (metadata == null) throw new InvalidOperationException("metadata is null");
+
+        this._htmlConversionBehaviors.MetaData = metadata;
+
+        return this;
+    }
+
     /// <summary>
     ///     Tells gotenberg to return a 409 response if there are exceptions in the Chromium console.
     /// </summary>

lib/Domain/Requests/Facets/ExtraHttpHeaders.cs

@@ -23,7 +23,7 @@ public void Add(string name, string value)
     {
         if (name.IsNotSet()) throw new ArgumentException("Header name is null or empty");
 
-        this._headers.Add(name, new[] { value });
+        this._headers.Add(name, [value]);
     }
 
     public void Add(string name, IEnumerable<string> values)

lib/Domain/Requests/Facets/HtmlConversionBehaviors.cs

@@ -56,6 +56,14 @@ public class HtmlConversionBehaviors : IConvertToHttpContent
     [MultiFormHeader(Constants.Gotenberg.Chromium.Shared.HtmlConvert.ExtraHttpHeaders)]
     public JObject? ExtraHeaders {  get; set; }
 
+    /// <summary>
+    /// The metadata to write to the PDF (JSON format).
+    /// Not all metadata are writable.
+    /// Consider taking a look at https://exiftool.org/TagNames/XMP.html#pdf for an (exhaustive?) list of available metadata.
+    /// </summary>
+    [MultiFormHeader(Constants.Gotenberg.Chromium.Shared.HtmlConvert.MetaData)]
+    public JObject? MetaData {  get; set; }
+
     /// <summary>
     /// Tells gotenberg to return a 409 response if there are exceptions in the Chromium console.
     /// </summary>

lib/Domain/Requests/Facets/Webhook.cs

@@ -93,7 +93,7 @@ public bool IsConfigured()
 
     public IEnumerable<(string, string?)> GetHeaders()
     {
-        if (!this.IsConfigured()) return Enumerable.Empty<(string, string?)>();
+        if (!this.IsConfigured()) return [];
 
         var webHookHeaders = new List<(string Name, string? Value)>
         {

lib/Infrastructure/Constants.cs

@@ -264,6 +264,8 @@ public static class HtmlConvert
 
                     public const string ExtraHttpHeaders = "extraHttpHeaders";
 
+                    public const string MetaData = "metadata";
+
                     //javascript
                     public const string FailOnConsoleExceptions = "failOnConsoleExceptions";