Document.Save() throws NullReferenceException on OSX

[svantreeck]

I am running into a NullReferenceException using Aspose.PDF 19.4 in my own application and narrowed it down to the Save method on a Document. To make sure it wasn't my code causing the issue, I tried running the hello world example in this repo but tweaked to save to a stream to match how my app was working, and got the below error. Any ideas how to fix this?

            // Initialize document object
            Document document = new Document();
            // Add page
            Page page = document.Pages.Add();
            // Add text to new page
            page.Paragraphs.Add(new Aspose.Pdf.Text.TextFragment("Hello World!"));
	   // Save updated PDF
			using (var stream = new MemoryStream())
			{
				document.Save(stream);
			}
            // ExEnd:1  

System.NullReferenceException: Object reference not set to an instance of an object
  at #=zrfrUImb7jZrPxl6ucZ5zNV9DARLP.#=zrIGtZ6o= (#=z7yZ2j1uLuKOW3Mjv7iBPtwH3Y3ZT #=zvgUMzhxilvJ$) [0x00014] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=zf5Xplt8SxpLmjY2gnjKga9k=.#=zCHp0IXk= (#=z7yZ2j1uLuKOW3Mjv7iBPtwH3Y3ZT #=zvgUMzhxilvJ$) [0x00035] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at at (wrapper managed-to-native) System.Reflection.MonoMethod.InternalInvoke(System.Reflection.MonoMethod,object,object[],System.Exception&)
  at System.Reflection.MonoMethod.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) [0x0003b] in /Users/builder/jenkins/workspace/build-package-osx-mono/2018-08/external/bockbuild/builds/mono-x64/mcs/class/corlib/System.Reflection/MonoMethod.cs:305
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zs919QWqrlYGtp0d8HnE2iVs= (System.Object #=znOmGh_c=) [0x00000] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zbuTtbUQf9v4z9CLlfpkWc5NONpP1NH61Xg== (System.Object #=znOmGh_c=) [0x00025] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zD1z8jhB_bImTFA1KQH_CXh8= (System.Reflection.MethodBase #=znOmGh_c=, System.Boolean #=zKJQ1vAs=) [0x0020c] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zr1qAW2dJZU56Fifz$DRtrJQ= (#=qA0cVKYayviYAiKvxD3jKmFCvKBcZO1cuNkLywGPCX4s= #=znOmGh_c=) [0x00029] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zjQ2kpb7QJHXuCFyqDIfbc6bxeif3Guj2t5kRHFY= () [0x0006f] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zoZhjcbxKCu1OlfqNiZQyhtBOhMag () [0x00005] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zs919QWqrlYGtp0d8HnE2iVs= (System.Object #=znOmGh_c=) [0x00000] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zbuTtbUQf9v4z9CLlfpkWc5NONpP1NH61Xg== (System.Object #=znOmGh_c=) [0x00025] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zeDxoLlmnn6sLuiwJZ3kySdEqr9Qm () [0x00021] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zQuJefDFFUH6arI2RL7Xny4w= (#=qA0cVKYayviYAiKvxD3jKmFCvKBcZO1cuNkLywGPCX4s= #=znOmGh_c=) [0x00005] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zjQ2kpb7QJHXuCFyqDIfbc6bxeif3Guj2t5kRHFY= () [0x0006f] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zoZhjcbxKCu1OlfqNiZQyhtBOhMag () [0x00005] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zs919QWqrlYGtp0d8HnE2iVs= (System.Object #=znOmGh_c=) [0x00000] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zbuTtbUQf9v4z9CLlfpkWc5NONpP1NH61Xg== (System.Object #=znOmGh_c=) [0x00025] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zeDxoLlmnn6sLuiwJZ3kySdEqr9Qm () [0x00021] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zyEPA4nnEbHwoj0a0kw== (System.Object #=znOmGh_c=, System.UInt32 #=zKJQ1vAs=) [0x0016f] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zoZhjcbxKCu1OlfqNiZQyhtBOhMag () [0x0001e] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zXiHq1JqAXT1nVsgy7_u_4Co= () [0x00066] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=z5$W8JnZoxMUxFZCZ9nBeVsRX25Eiv12nKg== () [0x00005] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zs919QWqrlYGtp0d8HnE2iVs= (System.Object #=znOmGh_c=) [0x00000] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zbuTtbUQf9v4z9CLlfpkWc5NONpP1NH61Xg== (System.Object #=znOmGh_c=) [0x00025] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zeDxoLlmnn6sLuiwJZ3kySdEqr9Qm () [0x00021] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zyEPA4nnEbHwoj0a0kw== (System.Object #=znOmGh_c=, System.UInt32 #=zKJQ1vAs=) [0x0016f] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=z5$W8JnZoxMUxFZCZ9nBeVsRX25Eiv12nKg== () [0x00024] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zQ5pdWvrfMJWQpyweT_AkOQA= (System.Object[] #=znOmGh_c=, System.Type[] #=zKJQ1vAs=, System.Type[] #=zLQM$Grw=, System.Object[] #=zkxlc94Q=) [0x000b0] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zmDDIFHbuPCYW5n5B6w== (System.IO.Stream #=znOmGh_c=, System.String #=zKJQ1vAs=, System.Object[] #=zLQM$Grw=, System.Type[] #=zkxlc94Q=, System.Type[] #=zx3KnP8k=, System.Object[] #=zmd0rShU=) [0x00010] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zvzW4XjAI4ieAQmFs5zIGtvMzO0v6ctZBpel8OF4= (System.IO.Stream #=znOmGh_c=, System.String #=zKJQ1vAs=, System.Object[] #=zLQM$Grw=) [0x00000] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at #=qBVcPFVNsk1VCnIglM9dyb854eZvi1sYdOocJizgIlOs=.#=zTrgnC51gLkD5hJWbJTysEN5HzUSZa6TI3j8OR_8= (System.IO.Stream #=znOmGh_c=, System.String #=zKJQ1vAs=, System.Object[] #=zLQM$Grw=) [0x00000] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at Aspose.Pdf.Document.#=zaQMY1WxSvSde (System.IO.Stream #=z_scZQvM=, Aspose.Pdf.SaveOptions #=zVOKmEcCtwEbL) [0x00141] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at Aspose.Pdf.Document.Save (System.IO.Stream output) [0x00009] in <6cf8ce1e23124d98df6de66c2a643c37>:0
  at Aspose.Pdf.Examples.CSharp.AsposePDF.QuickStart.HelloWorld.Run () [0x00036] in /Aspose.PDF-for-.NET/Examples/CSharp/AsposePDF/QuickStart/HelloWorld.cs:26
  at Aspose.Pdf.Examples.CSharp.RunExamples.Main () [0x00017] in /GitHub/Aspose.PDF-for-.NET/Examples/CSharp/RunExamples.cs:69

[svantreeck]

Also, this happens on netstandard 2.0/NetCoreApp 2.2 with a different stack trace using the 19.4 nuget package:

Exception thrown: 'System.NullReferenceException' in Aspose.Pdf.dll: 'Object reference not set to an instance of an object.'
   at #=qiU5gKTVK86AarXYAnvaBOxQOA0XVDuZru00A9_AYga4=.#=zXBtwSBLzda2_G9a41IF5YQs=(Object #=zqRDmNVM=)
   at #=qiU5gKTVK86AarXYAnvaBOxQOA0XVDuZru00A9_AYga4=.#=znGTCst0AWNesiDvV6Eq4rllDm2ulZ$3xQh5Vh_objbuj()
   at #=qiU5gKTVK86AarXYAnvaBOxQOA0XVDuZru00A9_AYga4=.#=zSR2Tpot4nMtwQdYXI3xLlt0EJytNe6busA==(Object #=zqRDmNVM=, UInt32 #=zX$ZZP8I=)
   at #=qiU5gKTVK86AarXYAnvaBOxQOA0XVDuZru00A9_AYga4=.#=z_qrD3AVS0GsHKyOIoWKkNiwWfmfYeA23UA==(Boolean #=zqRDmNVM=)
   at #=qiU5gKTVK86AarXYAnvaBOxQOA0XVDuZru00A9_AYga4=.#=z_qrD3AVS0GsHKyOIoWKkNiwWfmfYeA23UA==(Boolean #=zqRDmNVM=)
   at #=qiU5gKTVK86AarXYAnvaBOxQOA0XVDuZru00A9_AYga4=.#=z$SpgjR37J_YbwNc_D3_giTaCbBCxqRCyjw==()
   at #=qiU5gKTVK86AarXYAnvaBOxQOA0XVDuZru00A9_AYga4=.#=zvNKzj4lUeqJEMgAPlxiCz6I0fscgSFlqd5oY2M0=(Object[] #=zqRDmNVM=, Type[] #=zX$ZZP8I=, Type[] #=zCq$X$PI=, Object[] #=zC1Gb71M=)
   at #=qiU5gKTVK86AarXYAnvaBOxQOA0XVDuZru00A9_AYga4=.#=zYtbayufKcJpqUGOACug$yR9fosEe2J6jT85tdurYPYqE(Stream #=zqRDmNVM=, String #=zX$ZZP8I=, Object[] #=zCq$X$PI=, Type[] #=zC1Gb71M=, Type[] #=zAFl0CXU=, Object[] #=ziTWLoW8=)
   at #=qiU5gKTVK86AarXYAnvaBOxQOA0XVDuZru00A9_AYga4=.#=zXHZm77uSJ3f9Vt8P$wEQoQTEwPFe(Stream #=zqRDmNVM=, String #=zX$ZZP8I=, Object[] #=zCq$X$PI=)
   at #=qiU5gKTVK86AarXYAnvaBOxQOA0XVDuZru00A9_AYga4=.#=z6YuiouYDF8q3F6vgeUpLxyDEk5_9(Stream #=zqRDmNVM=, String #=zX$ZZP8I=, Object[] #=zCq$X$PI=)
   at Aspose.Pdf.Document.#=zc987sPODI9gV(Stream #=zUBYR2bw=, SaveOptions #=zalZVzje3NyLF)
   at Aspose.Pdf.Document.Save(Stream output)

[farhan-raza]

@svantreeck

Thank you for contacting support.

We are investigating it in our environment and will get back to you with our findings soon.

PS: I work with Aspose as Developer Evangelist.

[farhan-raza]

@svantreeck

Thank you for being patient.

We have tested the scenario with Aspose.PDF for .NET 19.5 in MacOS version 10.14.4 Mojave, but the problem did not reproduce. Would you please share a sample application with us so that we may investigate further and help you out.

[SergeySagan]

I am also having this issue. It works when I run locally, but when deployed to our kubernates Debian environment, getting the same error as described in the original post.

[brianjbeach]

I am seeing the same on OSX. This is the simplest example I could dream up to repro.

var file = new Aspose.Pdf.Document("origianl.pdf");
file.Save("new.pdf");

[asadalikhan90]

@brianjbeach
@serjster
@svantreeck

In order to use the API in a non-Windows environment, please make sure to install the following packages:

• libgdiplus package
• Microsoft Core Fonts (msttcorefonts package)

Please note that such exceptions are usually caused due to the absence of required fonts. Please try to install the suggested packages in your system and in case you still face the issue, please let us know.

[abdul-kurtosys]

Having this same issue with the Aspose.PDF 20.10 on MacOS version 10.15.7 Catalina

I attempted to install libgdiplus via brew https://formulae.brew.sh/formula/mono-libgdiplus

I also have office installed so I should have the Microsoft Core Fonts installed

[asadalikhan90]

@abdul-kurtosys

Are you facing this issue while processing an existing PDF document or creating a new one from scratch? Please share some more details of the scenario along with the sample code snippet that you are using. Also, please try using Aspose.PDF for .NET 20.12 and let us know if an issue still persists.

PS: It is recommended to post such issues in our official forum where they can be addressed and tracked appropriately.

[xopxop]

https://docs.aspose.com/pdf/net/hello-world-example/
I came across the same problem with this example. It crashed right at the document.save() method
I am using macOs Big Sur v11.2.3

[mudassirfayyaz]

@xopxop
I have recently configured libgdiplus on macOs Big Sur v11.2.3. You need to use the Mac Terminal and with sudo please execute following two commands in order. I hope this will resolve all the dependencies on your end and will install the package.

xcode-select --install
brew install mono-libgdiplus

[danielgran]

Same on here, any updates?
Offical Thread gets no updates, too.
https://forum.aspose.com/t/null-reference-error-while-saving-the-document/15342

[asadalikhan90]

@danielgran

We regret to inform you that the earlier logged ticket is not yet resolved. The issue is currently under the phase of the investigation. We have also posted an update in the original official thread. You may please follow up there about progress on issue resolution.

We apologize for the inconvenience caused due to this bug.

[danielgran]

@asadalikhan90

This issue is open since 4 years now.

I found a rather messy workaround checking if every page is saveable.
You guys dont mind fixing this asap? :D

Greeting