System.NullReferenceException: Object reference not set to an instance of an object.

[hunorkantor]

[15:48:46 INF] [16.0.3] Loading 1 Work Items
[15:48:50 WRN] [16.0.3]   [SKIP] Already Exists a Link of type System.LinkTypes.Hierarchy-Forward where wiSourceL=653007, wiSourceR=661669, wiTargetL=84, wiTargetR=90
[15:48:50 INF] [16.0.3] GitRepositoryEnricher: Enriching 84 To fix Git Repo Links
[15:48:51 ERR] [16.0.3] System.NullReferenceException: Object reference not set to an instance of an object.
   at MigrationTools.Tools.TfsGitRepositoryTool.Enrich(TfsProcessor processor, WorkItemData sourceWorkItem, WorkItemData targetWorkItem) in D:\a\azure-devops-migration-tools\azure-devops-migration-tools\src\MigrationTools.Clients.TfsObjectModel\Tools\TfsGitRepositoryTool.cs:line 112
   at MigrationTools.Processors.TfsWorkItemMigrationProcessor.ProcessWorkItemLinks(IWorkItemMigrationClient sourceStore, IWorkItemMigrationClient targetStore, WorkItemData sourceWorkItem, WorkItemData targetWorkItem) in D:\a\azure-devops-migration-tools\azure-devops-migration-tools\src\MigrationTools.Clients.TfsObjectModel\Processors\TfsWorkItemMigrationProcessor.cs:line 658
   at MigrationTools.Processors.TfsWorkItemMigrationProcessor.<ProcessWorkItemAsync>d__32.MoveNext() in D:\a\azure-devops-migration-tools\azure-devops-migration-tools\src\MigrationTools.Clients.TfsObjectModel\Processors\TfsWorkItemMigrationProcessor.cs:line 554
System.NullReferenceException: Object reference not set to an instance of an object.
   at MigrationTools.Tools.TfsGitRepositoryTool.Enrich(TfsProcessor processor, WorkItemData sourceWorkItem, WorkItemData targetWorkItem) in D:\a\azure-devops-migration-tools\azure-devops-migration-tools\src\MigrationTools.Clients.TfsObjectModel\Tools\TfsGitRepositoryTool.cs:line 112
   at MigrationTools.Processors.TfsWorkItemMigrationProcessor.ProcessWorkItemLinks(IWorkItemMigrationClient sourceStore, IWorkItemMigrationClient targetStore, WorkItemData sourceWorkItem, WorkItemData targetWorkItem) in D:\a\azure-devops-migration-tools\azure-devops-migration-tools\src\MigrationTools.Clients.TfsObjectModel\Processors\TfsWorkItemMigrationProcessor.cs:line 658
   at MigrationTools.Processors.TfsWorkItemMigrationProcessor.<ProcessWorkItemAsync>d__32.MoveNext() in D:\a\azure-devops-migration-tools\azure-devops-migration-tools\src\MigrationTools.Clients.TfsObjectModel\Processors\TfsWorkItemMigrationProcessor.cs:line 554
Error logged to Elmah.io!

{
  "Serilog": {
    "MinimumLevel": "Information"
  },
  "MigrationTools": {
    "Version": "16.0",
    "Endpoints": {
      "Source": {
        "EndpointType": "TfsTeamProjectEndpoint",
        "Collection": "https://ss00pazure.adtr.th.tryg.com/NordicCollection/",
        "Project": "DEV_SUPPORT",
        "Authentication": {
          "AuthenticationMode": "AccessToken",
          "NetworkCredentials": null,
          "AccessToken": ""
        },
        "ReflectedWorkItemIdField": "ReflectedWorkItemId",
        "AllowCrossProjectLinking": false,
        "LanguageMaps": {
          "AreaPath": "Area",
          "IterationPath": "Iteration"
        },
        "EndpointEnrichers": null
      },
      "Target": {
        "EndpointType": "TfsTeamProjectEndpoint",
        "Collection": "https://dev.azure.com/TrygHansaTest",
        "Project": "DEV_SUPPORT",
        "Authentication": {
          "AuthenticationMode": "AccessToken",
          "NetworkCredentials": null,
          "AccessToken": ""
        },
        "ReflectedWorkItemIdField": "ReflectedWorkItemId",
        "AllowCrossProjectLinking": false,
        "LanguageMaps": {
          "AreaPath": "Area",
          "IterationPath": "Iteration"
        },
        "EndpointEnrichers": null
      }
    },
    "Processors": [
      {
        "ProcessorType": "TfsWorkItemMigrationProcessor",
        "Enabled": true,
        "UpdateCreatedDate": false,
        "UpdateCreatedBy": true,
        "WIQLQuery": "SELECT [System.Id] FROM WorkItems WHERE  System.Id = '653007' AND [System.TeamProject] = @TeamProject AND [System.WorkItemType] NOT IN ('Test Suite', 'Test Plan','Shared Steps','Shared Parameter','Feedback Request', 'Code Review','Code Review Response','Code Review Request') ORDER BY [System.ChangedDate] desc",
        "FixHtmlAttachmentLinks": true,
        "WorkItemCreateRetryLimit": 5,
        "FilterWorkItemsThatAlreadyExistInTarget": false,
        "PauseAfterEachWorkItem": false,
        "AttachRevisionHistory": true,
        "GenerateMigrationComment": true,
        "WorkItemIDs": null,
        "MaxGracefulFailures": 0,
        "SkipRevisionWithInvalidIterationPath": false,
        "SkipRevisionWithInvalidAreaPath": false,
        "Enrichers": null,
        "SourceName": "Source",
        "TargetName": "Target",
        "RefName": ""
      }
    ],
	
    "CommonTools": {
      "FieldMappingTool": {
        "Enabled": false,
        "FieldMaps": []
      },
	   "TfsGitRepositoryTool": {
        "Enabled": false,
        "Mappings": null
      }
    }
  }
}

[MrHinsh]

Your "Mappings": null should not be null. If you change it to [] it will work... but having mappings is a good idea if its enabled.

[hunorkantor]

I changed the config as you proposed, but now I am getting different error. Attached the error print screen and the config:
[14:09:38 ERR] [16.0.3] System.NullReferenceException: Object reference not set to an instance of an object.
at MigrationTools.Tools.TfsGitRepositoryTool.GetTargetRepoName(Dictionary2 gitRepoMappings, TfsGitRepositoryInfo repoInfo) in D:\a\azure-devops-migration-tools\azure-devops-migration-tools\src\MigrationTools.Clients.TfsObjectModel\Tools\TfsGitRepositoryTool.cs:line 237 at MigrationTools.Tools.TfsGitRepositoryTool.Enrich(TfsProcessor processor, WorkItemData sourceWorkItem, WorkItemData targetWorkItem) in D:\a\azure-devops-migration-tools\azure-devops-migration-tools\src\MigrationTools.Clients.TfsObjectModel\Tools\TfsGitRepositoryTool.cs:line 124 at MigrationTools.Processors.TfsWorkItemMigrationProcessor.ProcessWorkItemLinks(IWorkItemMigrationClient sourceStore, IWorkItemMigrationClient targetStore, WorkItemData sourceWorkItem, WorkItemData targetWorkItem) in D:\a\azure-devops-migration-tools\azure-devops-migration-tools\src\MigrationTools.Clients.TfsObjectModel\Processors\TfsWorkItemMigrationProcessor.cs:line 658 at MigrationTools.Processors.TfsWorkItemMigrationProcessor.<ProcessWorkItemAsync>d__32.MoveNext() in D:\a\azure-devops-migration-tools\azure-devops-migration-tools\src\MigrationTools.Clients.TfsObjectModel\Processors\TfsWorkItemMigrationProcessor.cs:line 554 System.NullReferenceException: Object reference not set to an instance of an object. at MigrationTools.Tools.TfsGitRepositoryTool.GetTargetRepoName(Dictionary2 gitRepoMappings, TfsGitRepositoryInfo repoInfo) in D:\a\azure-devops-migration-tools\azure-devops-migration-tools\src\MigrationTools.Clients.TfsObjectModel\Tools\TfsGitRepositoryTool.cs:line 237
at MigrationTools.Tools.TfsGitRepositoryTool.Enrich(TfsProcessor processor, WorkItemData sourceWorkItem, WorkItemData targetWorkItem) in D:\a\azure-devops-migration-tools\azure-devops-migration-tools\src\MigrationTools.Clients.TfsObjectModel\Tools\TfsGitRepositoryTool.cs:line 124
at MigrationTools.Processors.TfsWorkItemMigrationProcessor.ProcessWorkItemLinks(IWorkItemMigrationClient sourceStore, IWorkItemMigrationClient targetStore, WorkItemData sourceWorkItem, WorkItemData targetWorkItem) in D:\a\azure-devops-migration-tools\azure-devops-migration-tools\src\MigrationTools.Clients.TfsObjectModel\Processors\TfsWorkItemMigrationProcessor.cs:line 658
at MigrationTools.Processors.TfsWorkItemMigrationProcessor.d__32.MoveNext() in D:\a\azure-devops-migration-tools\azure-devops-migration-tools\src\MigrationTools.Clients.TfsObjectModel\Processors\TfsWorkItemMigrationProcessor.cs:line 554
Error logged to Elmah.io!
!! Check for latest version - We fix issues constantly - If not, please create a discussion on https://github.com/nkdAgility/azure-devops-migration-tools/discussions so we can get this fixed !!

configuration-upgraded_wo_cred.json

[JohanSpannare]

The correct default config should be for JSON to C# Dictionary<string, string>

      "TfsGitRepositoryTool": {
        "Enabled": true,
        "Mappings": [{}]
      }