Arvados

h1. Browsing shared projects

It is desirable to have a "projects shared with me" virtual directory in FUSE and WebDAV. There is an API endpoint for this, but it's not obvious how to present it as a filesystem because the entries' names are not unique.

Any solution would need to support the following behavior:

# A project P1, named "new project", is created by user U1 and shared with user U2.

# User U2 opens the "shared projects" virtual directory in WebDAV or FUSE, finds "new project" directory in the listing, and opens it.

# A second project P2, also called "new project", is shared with user U2.

# User U2 saves a new collection C1 in the directory they opened in step 2.

# The new collection C1 is in project P1 -- not P2.

# User U2 opens the "shared projects" virtual directory and discovers that there are now two shared projects named "new project".

# User U2 opens the P2 directory.

# User U1 renames P1 to "project formerly known as new project".

# User U2 saves a new collection C2 in the directory they opened in step 7.

# The new collection C2 is in project P2 -- not P1.

Proposal: Include project UUID in every entry.

* Project P1 appears in "shared projects" with the name "new project--zzzzz-j7d0g-pppppppppp11111"

* Behavior is very predictable

* Directory listings and file paths are ugly

* "name--uuid" has a slight advantage that it doesn't require shell quoting except when the original name already requires shell quoting (unlike "name (uuid)")

Rejected alternatives:

Include project UUID only when name conflicts exist.

* Project P1 appears as "new project" at first

* After step 3, P1 changes its name to "new project (zzzzz-j7d0g-pppppppppp11111)"

* In step 4, U2's "save" operation fails because the "new project" directory no longer exists

Include project UUID only when name conflicts exist, and even then, not for the oldest project

* step 4 fails depending on whether P2 happened to exist before step 1

Include project UUID only when name conflicts exist, and even then, not for the project that first became visible to U1

* Expensive to compute

* Feels unpredictable for users

* P2 changes its name in the listing during step 8, and step 9 fails.