Publish files with UniversalPackages#0 - "The path provided is invalid." - azure-devops

Question

I'm trying to publish a file (Helloworld.txt) to my Universal Packages directory to pass on to a different stage within my Release Piepline (using UniversalPackages#0).
I cannot for the life of me figure out how to make it work.
I'm trying to follow this KB but it leaves me confused:
https://learn.microsoft.com/en-us/azure/devops/pipelines/artifacts/universal-packages?view=azure-devops&tabs=yaml
For example, I can't determine what vstsFeedPublish is and don't know if vstsFeedPackagePublish can be a new name I make up on the spot or if it is actually the name of an existing file/folder.
What "path" am I entering incorrectly that's making it fail?
Stage Deployment Steps:
Helloworld Output to TXT:
cd $(Build.ArtifactStagingDirectory)
"$(System.DefaultWorkingDirectory)/Helloworld Build/Helloworld EXE Folder/Helloworld.exe" >> WriteLineOutput.txt
I cd into $(Build.ArtifactStagingDirectory) first because that is the default folder UniversalPackages#0 looks to publish files, so I want WriteLineOutput.txt to be generated there.
Publish Output TXT to Universal Dir (YAML):
steps:
- task: UniversalPackages#0
displayName: 'Publish Output TXT to Universal Dir'
inputs:
command: publish
vstsFeed: '0a3a9abd-83fd-495f-967b-e986c523f2d2'
vstsPackageVersion: 1
vstsFeedPublish: '0a3a9abd-83fd-495f-967b-e986c523f2d2'
vstsFeedPackagePublish: 'writelineoutput-txt'
versionOption: minor
packagePublishDescription: 'TXT output from Helloworld.exe'
Working Directory Structure:
"Publish Output TXT to Universal Dir" Task Output:
2019-12-02T03:35:35.2264352Z ##[section]Starting: Publish Output TXT to Universal Dir
2019-12-02T03:35:35.2381247Z ==============================================================================
2019-12-02T03:35:35.2381328Z Task : Universal packages
2019-12-02T03:35:35.2381359Z Description : Download or publish Universal Packages
2019-12-02T03:35:35.2381412Z Version : 0.160.1
2019-12-02T03:35:35.2381461Z Author : Microsoft Corporation
2019-12-02T03:35:35.2381490Z Help : https://learn.microsoft.com/azure/devops/pipelines/tasks
2019-12-02T03:35:35.2381520Z ==============================================================================
2019-12-02T03:35:36.0651445Z SYSTEMVSSCONNECTION exists true
2019-12-02T03:35:36.6058302Z Downloading: https://0t3vsblobprodcus362.vsblob.vsassets.io/artifacttool/artifacttool-win10-x64-Release_0.2.128.zip?sv=2017-04-17&sr=b&sig=tHZQU3V2DuXcC0Y1xnmzB7Zw7kMdjJSijWVDiztc9UE%3D&spr=https&se=2019-12-02T04%3A35%3A37Z&sp=r&P1=1575261037&P2=11&P3=2&P4=LS6Ffab5P%2bb8Q9r3aGsGLlK9ELRD6bRxxlTkDc5aEc8%3d
2019-12-02T03:35:39.3862184Z Caching tool: ArtifactTool 0.2.128 x64
2019-12-02T03:35:40.4414172Z SYSTEMVSSCONNECTION exists true
2019-12-02T03:35:41.4415128Z Publishing package: writelineoutput-txt, version: 0.1.0 using feed id: 65dc653c-5c3b-771c-b308-34b199d8fcee, project: null
2019-12-02T03:35:41.4469092Z [command]C:\hostedtoolcache\windows\ArtifactTool\0.2.128\x64\ArtifactTool.exe universal publish --feed 65dc653c-5c3b-771c-b308-34b199d8fcee --service https://vsrm.dev.azure.com/sawtooth-capstone/ --package-name writelineoutput-txt --package-version 0.1.0 --path D:\a\r1\a\$(Build.ArtifactStagingDirectory) --patvar UNIVERSAL_PUBLISH_PAT --verbosity None --description "TXT output from Helloworld.exe"
2019-12-02T03:35:44.0492154Z {"#t":"2019-12-02T03:35:43.3152933Z","#m":"ApplicationInsightsTelemetrySender will correlate events with X-TFS-Session 23e076ea-5122-4c06-b92a-2aef5974defd","#i":"8778ba0f","SourceContext":"ArtifactTool.Commands.UPackPublishCommand","UtcTimestamp":"2019-12-02 03:35:43.315Z"}
2019-12-02T03:35:44.0493421Z {"#t":"2019-12-02T03:35:43.7170274Z","#m":"Ensuring that the package does not yet exist...","#i":"40e01e14","SourceContext":"ArtifactTool.Commands.UPackPublishCommand","UtcTimestamp":"2019-12-02 03:35:43.717Z"}
2019-12-02T03:35:44.0494251Z {"#t":"2019-12-02T03:35:43.8900269Z","#m":"Package does not yet exist","#i":"c781eca5","SourceContext":"ArtifactTool.Commands.UPackPublishCommand","UtcTimestamp":"2019-12-02 03:35:43.890Z"}
2019-12-02T03:35:44.0494769Z {"#t":"2019-12-02T03:35:43.8913512Z","#m":"Pushing content...","#i":"3aa40378","SourceContext":"ArtifactTool.Commands.UPackPublishCommand","UtcTimestamp":"2019-12-02 03:35:43.891Z"}
2019-12-02T03:35:44.0495859Z {"#t":"2019-12-02T03:35:43.9060246Z","#m":"DedupManifestArtifactClient will correlate http requests with X-TFS-Session 23e076ea-5122-4c06-b92a-2aef5974defd","#i":"09a6f3ce","SourceContext":"ArtifactTool.Commands.UPackPublishCommand","UtcTimestamp":"2019-12-02 03:35:43.906Z"}
2019-12-02T03:35:44.0496478Z {"#t":"2019-12-02T03:35:44.0301714Z","#m":"The path provided is invalid.","#i":"05178f7d","#l":"Error","SourceContext":"ArtifactTool.Program","UtcTimestamp":"2019-12-02 03:35:44.030Z"}
2019-12-02T03:35:44.0776082Z ##[error]Error: An unexpected error occurred while trying to push the package. Exit code(16) and error({"#t":"2019-12-02T03:35:43.3152933Z","#m":"ApplicationInsightsTelemetrySender will correlate events with X-TFS-Session 23e076ea-5122-4c06-b92a-2aef5974defd","#i":"8778ba0f","SourceContext":"ArtifactTool.Commands.UPackPublishCommand","UtcTimestamp":"2019-12-02 03:35:43.315Z"}
{"#t":"2019-12-02T03:35:43.7170274Z","#m":"Ensuring that the package does not yet exist...","#i":"40e01e14","SourceContext":"ArtifactTool.Commands.UPackPublishCommand","UtcTimestamp":"2019-12-02 03:35:43.717Z"}
{"#t":"2019-12-02T03:35:43.8900269Z","#m":"Package does not yet exist","#i":"c781eca5","SourceContext":"ArtifactTool.Commands.UPackPublishCommand","UtcTimestamp":"2019-12-02 03:35:43.890Z"}
{"#t":"2019-12-02T03:35:43.8913512Z","#m":"Pushing content...","#i":"3aa40378","SourceContext":"ArtifactTool.Commands.UPackPublishCommand","UtcTimestamp":"2019-12-02 03:35:43.891Z"}
{"#t":"2019-12-02T03:35:43.9060246Z","#m":"DedupManifestArtifactClient will correlate http requests with X-TFS-Session 23e076ea-5122-4c06-b92a-2aef5974defd","#i":"09a6f3ce","SourceContext":"ArtifactTool.Commands.UPackPublishCommand","UtcTimestamp":"2019-12-02 03:35:43.906Z"}
{"#t":"2019-12-02T03:35:44.0301714Z","#m":"The path provided is invalid.","#i":"05178f7d","#l":"Error","SourceContext":"ArtifactTool.Program","UtcTimestamp":"2019-12-02 03:35:44.030Z"})
2019-12-02T03:35:44.0789627Z ##[error]Packages failed to publish
2019-12-02T03:35:44.0898947Z ##[section]Finishing: Publish Output TXT to Universal Dir
Key Lines:
2019-12-02T03:35:44.0496478Z {"#t":"2019-12-02T03:35:44.0301714Z","#m":"The path provided is invalid.","#i":"05178f7d","#l":"Error","SourceContext":"ArtifactTool.Program","UtcTimestamp":"2019-12-02 03:35:44.030Z"}
2019-12-02T03:35:44.0776082Z ##[error]Error: An unexpected error occurred while trying to push the package. Exit code(16) and error({"#t":"2019-12-02T03:35:43.3152933Z","#m":"ApplicationInsightsTelemetrySender will correlate events with X-TFS-Session 23e076ea-5122-4c06-b92a-2aef5974defd","#i":"8778ba0f","SourceContext":"ArtifactTool.Commands.UPackPublishCommand","UtcTimestamp":"2019-12-02 03:35:43.315Z"}
EDIT:
Well, I read it's best practice to use the Build pipeline to publish artifacts and the Release pipeline to run/test them, so I decided to just publish the artifact from the Build pipeline instead of trying to make the same Helloworld.txt again during the Release pipeline. But I'm willing to take the inevitable downvotes if someone can help me figure out how to publish new files created in the Release pipeline into the Universal packages directory.

Answer 1

I'd better suggest you call exe to generate the txt file in Build. Then publish them as artifacts to release pipeline. Then you can easily pick the HelloWord.txt file in Release pipeline.
This task can be used both in Build and Release pipeline. The difference between apply this task in Build and release just be the Path to file(s) to publish value which you very confused.
For Release pipeline:
If what you want is publish the HelloWord.txt into package, just click , and then select the corresponding file HelloWord.txt from it.
So, what its value should be $(System.DefaultWorkingDirectory)/{Source alias}/{artifact name}/s/HelloWorld.txt.
Note: This way is applied when you put the txt generated in Build pipeline, and then publish them as artifact and used in release pipeline.
Similar in Build pipeline, you can also select the file from that button. For its YAML format, just input the file name like:
inputs:
command: publish
publishDirectory: 'azure-pipelines.txt'
vstsFeedPublish: '*****'
vstsFeedPackagePublish: merlin
versionOption: custom
versionPublish: 0.0.1
packagePublishDescription: published in 2019/12/2
If azure-pipelines.txt file is under a folder, just input it as a {folder name}/azure-pipelines.txt.
In your issue, if you want to put the file generate and the package publish both in Build pipeline. Since I do not very clear know how's your HellowWorld.exe script like. The location of HelloWorld.txt is decided by your script. If you did not define the generated file location in script, as default, this txt file path should same with exe. According to the pic you shared, seem its path is HelloWorld EXE Folder/HelloWorld.txt. I suggest you can use private agent firstly to run this Build to confirm its(.txt) path.
vstsFeedPublish should be the existing feed you have created in your project. Here it can not be the new name that dose not exist before the pipeline executed.
vstsFeedPackagePublish is the package name you want it stored in feed. For me as sample, here I name it as merlin. After the release finished:
You can specify a new name or use the exists one. Use a new name means create a new package in Feed, and use the exists one just means the version incremental.