Git Credential Manager and ContentUrl with port

Hi,

As is well documented in this issue, internal GitLab repositories don’t play nice with SourceLink, but there is a workaround of using a proxy to retrieve the source via the GitLab API, by specifying the proxy URL via the ContentUrl property:

<SourceLinkGitLabHost Include="gitlab.myinternal.com" ContentUrl="https://blah:1234/" />

I’ve been putting a proxy together, and it all seems to work well, but I’ve noticed an oddity with how the credentials are retrieved from Git Credential Manager.

If I run my proxy on a URL with a port (e.g. https://blah:1234), and register credentials with GCM:

> git credential-manager-core store
protocol=https
host=blah:1234
username=myusername
password=mypassword
^Z

… when the time comes to fetch some code, Source Link gives an error:

Source Link Error:
git-credential-manager-core.exe: Could not obtain credentials. Process failed with exit code -1.
ERROR: The request failed with code 401 : "Unauthorized".

HOWEVER, if I use the same git credential-manager-core store command but omit the port:

> git credential-manager-core store
protocol=https
host=blah
username=myusername
password=mypassword
^Z

… then Source Link is happy, and all goes well.

So I don’t know if this is a Source Link or Visual Studio thing, but it looks like the port gets stripped when asking for credentials from GCM, which I don’t think is right.

This has another knock-on effect … if the credentials are not pre-registered in GCM, a git credential-manager-core get command will usually launch a credentials login dialog if it detects a service at the specified host, and that does not happen from VS when the URL has a port, so a user is forced to add credentials manually.

EDIT: a bit more evidence … here’s me requesting GCM credentials for my proxy running on localhost:5042:

As you can see, GCM prompts for credentials, as it has detected the service at the given location. And now here’s me requesting the credentials, but omitting the port:

So it looks like GCM does want the full host (name and port), but I’m pretty sure that VisualStudio/SourceLink is only requesting credentials for the host name (without the port).

[peeveen]

@chuckries I got an email telling me that this was fixed in VS 17.5 Preview 1, so I gave it a try, and it seems to be working. I’ll close this. Thanks for your help.

[peeveen]

This all sounds very promising. Thanks very much for this. I expect I will eventually be running the proxy again a “proper” hostname (without a port), but I thought I’d better bring this to your attention, as it looked like a defect.