Unexpected NullReferenceException when trying to create CkanModule from JSON

[keyspace]

Running on Arch linux 64-bit, mono 4.4.0.40, CKAN git master.

Essentially a duplicate of #1681.

The stack trace to mono ./ckan.exe update -d is:

Unhandled Exception:
System.NullReferenceException: Object reference not set to an instance of an object
  at CKAN.Repo.ProcessRegistryMetadataFromJSON (System.String metadata, CKAN.Registry registry, System.String filename) <0x40b9cc50 + 0x00242> in <filename unknown>:0 
  at CKAN.Repo.UpdateRegistryFromTarGz (System.String path, CKAN.Registry registry) <0x40b9a160 + 0x002d3> in <filename unknown>:0 
  at CKAN.Repo.UpdateRegistry (System.Uri repo, CKAN.Registry registry, CKAN.KSP ksp, IUser user, Boolean clear) <0x40b32a60 + 0x001c3> in <filename unknown>:0 
  at CKAN.Repo.UpdateAllRepositories (CKAN.RegistryManager registry_manager, CKAN.KSP ksp, IUser user) <0x40b316e0 + 0x00103> in <filename unknown>:0 
  at CKAN.CmdLine.Update.UpdateRepository (CKAN.KSP ksp, System.String repository) <0x40af6e70 + 0x00043> in <filename unknown>:0 
  at CKAN.CmdLine.Update.RunCommand (CKAN.KSP ksp, System.Object raw_options) <0x40af6970 + 0x00147> in <filename unknown>:0 
  at CKAN.CmdLine.MainClass.Main (System.String[] args) <0x40aaa340 + 0x00efb> in <filename unknown>:0 
[ERROR] FATAL UNHANDLED EXCEPTION: System.NullReferenceException: Object reference not set to an instance of an object
  at CKAN.Repo.ProcessRegistryMetadataFromJSON (System.String metadata, CKAN.Registry registry, System.String filename) <0x40b9cc50 + 0x00242> in <filename unknown>:0 
  at CKAN.Repo.UpdateRegistryFromTarGz (System.String path, CKAN.Registry registry) <0x40b9a160 + 0x002d3> in <filename unknown>:0 
  at CKAN.Repo.UpdateRegistry (System.Uri repo, CKAN.Registry registry, CKAN.KSP ksp, IUser user, Boolean clear) <0x40b32a60 + 0x001c3> in <filename unknown>:0 
  at CKAN.Repo.UpdateAllRepositories (CKAN.RegistryManager registry_manager, CKAN.KSP ksp, IUser user) <0x40b316e0 + 0x00103> in <filename unknown>:0 
  at CKAN.CmdLine.Update.UpdateRepository (CKAN.KSP ksp, System.String repository) <0x40af6e70 + 0x00043> in <filename unknown>:0 
  at CKAN.CmdLine.Update.RunCommand (CKAN.KSP ksp, System.Object raw_options) <0x40af6970 + 0x00147> in <filename unknown>:0 
  at CKAN.CmdLine.MainClass.Main (System.String[] args) <0x40aaa340 + 0x00efb> in <filename unknown>:0 

Avoiding it as outlined in pull #1700 (essentially doing nothing) I get:

311 [1] INFO CKAN.Repo (null) - Downloading https://github.com/KSP-CKAN/CKAN-meta/archive/master.tar.gz
313 [1] DEBUG CKAN.Net (null) - Downloading https://github.com/KSP-CKAN/CKAN-meta/archive/master.tar.gz to /tmp/CdFileMgr/70ce8316-d267-4f.tmp
3023 [1] DEBUG CKAN.Repo (null) - Starting registry update from tar.gz file: "/tmp/CdFileMgr/70ce8316-d267-4f.tmp".
3026 [1] DEBUG CKAN.Repo (null) - Skipping archive entry CKAN-meta-master/
3026 [1] DEBUG CKAN.Repo (null) - Skipping archive entry CKAN-meta-master/A6Intruder/
3026 [1] DEBUG CKAN.Repo (null) - Reading CKAN data from CKAN-meta-master/A6Intruder/A6Intruder-104.105.ckan
3027 [1] DEBUG CKAN.Repo (null) - Converting metadata from JSON.
3027 [1] ERROR CKAN.Repo (null) - Error processing CKAN-meta-master/A6Intruder/A6Intruder-104.105.ckan (exception tree leaf)

Unhandled Exception:
System.IO.FileNotFoundException: Could not load file or assembly 'Autofac, Version=3.5.0.0, Culture=neutral, PublicKeyToken=17863af14b0044da' or one of its dependencies.
File name: 'Autofac, Version=3.5.0.0, Culture=neutral, PublicKeyToken=17863af14b0044da'
  at CKAN.Repo.ProcessRegistryMetadataFromJSON (System.String metadata, CKAN.Registry registry, System.String filename) <0x409a6c50 + 0x00087> in <filename unknown>:0 
[ERROR] FATAL UNHANDLED EXCEPTION: System.IO.FileNotFoundException: Could not load file or assembly 'Autofac, Version=3.5.0.0, Culture=neutral, PublicKeyToken=17863af14b0044da' or one of its dependencies.
File name: 'Autofac, Version=3.5.0.0, Culture=neutral, PublicKeyToken=17863af14b0044da'
  at CKAN.Repo.ProcessRegistryMetadataFromJSON (System.String metadata, CKAN.Registry registry, System.String filename) <0x409a6c50 + 0x00087> in <filename unknown>:0

The assembly not loading is troubling (and json.net wrapping exceptions is outright annoying).

Breakpoints led me to a CkanModule.FromJson(metadata) call which seemingly throws, because module is never found (next line, 33).

[keyspace]

OK, Autofac.dll missing can be remedied by dropping it in the same dir as ckan.exe (top-level in my case). This allows for the update to finish successfully (EDIT: that is, CkanModule.FromJson() is called without exceptions flying around - not sure what's going on here).

[dbent]

OK, Autofac.dll missing can be remedied by dropping it in the same dir as ckan.exe (top-level in my case).

Weird, Autofac should be ILRepack'd into the executable. I'll have to investigate myself on my Arch install.

[dbent]

@keyspace Actually, I see you built CKAN off our master, our build is convoluted and filled with redundant scripts (something I'm working to rectify). Does this problem occur with the executable found on the releases page or the most recent version built from master?

[keyspace]

It doesn't happen with the pre-built .exe on the releases page.

It only happens if I build myself (including the stable 1.16.1 .tar.gz), so I assume it's the build environment in some way. The thing that's changed in the last days is I installed monodevelop. Not sure how relevant.

[dbent]

@keyspace If you build it yourself, you'll want to use the bin/build perl script, which does the necessary repacking to include the appropriate dependencies. Not the old build.sh in the root.

#1589 is the first step in consolidating our build setup.

[keyspace]

Ah! I used to make build before, but then set up a separate user for development, and started using build.sh (no shell history).

Guess I wanted to get my feet wet with KSP modding, and jumped off the cliff head-first.

This is even covered in the manual, so closing. Sorry for the noise.