[gritzko]

In my current project I use URIs to refer to absolutely any entity in a git(-ish) repo. Files, branches, revisions, diffs, anything. URI turns out to be a really good addressing scheme for everything. Surprise. But the most used and abused element is always the path. Query takes a lot of that mess away. Might have been unmanageable otherwise.

https://github.com/gritzko/beagle

[gritzko]

In fact, GitHub URIs are a good example of overusing paths: https://github.com/gritzko/beagle/blob/a7e17290a39250092055f...

  - user gritzko,
  - project beagle, 
  - view blob, 
  - commit a7e17290a39250092055fcda5ae7015868dabdb4, 
  - file path VERBS.md

... all concatenated indiscriminately.

[altairprime]

That’s not an indiscriminate hierarchy.

Grouping data by user is common and normal in computing: /home laid precedent decades ago.

Project directories are an extremely common grouping within a user’s work sets. Yeah, some of us just dump random files in $HOME, but this is still a sensible tier two path component.

The choice to make ‘view metadata-wrapped content in browser HTML output’ the default rather than ‘view raw file contents’ the default is legitimate for their usage. One could argue that using custom http headers would be preferable to a path element (to the exclusion of JavaScript being able to access them, iirc?) or that the path element blob should be moved into the domain component or should prefix rather than suffix the operands; all valid choices, but none implicitly better or worse here.

Object hash is obviously mandatory for git permalinks, and is perhaps the only mandatory component here. (But notably, that’s not the same as a commit hash.) However, such paths could arguably be interpreted as maximally user-hostile.

File path, interestingly enough, is completely disposable if one refers to a specific result object hash within a commit, but if the prior object hash was required to be a commit, then this is a valid unique identifier for the filesystem-tree contents of that commit. You could use the object hash instead of the full path within the commit hash, but that’s a pretty user-hostile way to go about this.

So, then, which part of the ordering and path selections do you consider indiscriminate, and why?

[em-bee]

actually, instead of the object hash, you could also use the commit-hash. then the filename would be mandatory, but the url would be more readable and usable: give me the file VERBS.md as it is at commit <hash>

[masklinn]

That's actually what it is here, a7e17290a39250092055fcda5ae7015868dabdb4 is a commit's oid: https://github.com/gritzko/beagle/commit/a7e17290a3925009205...

[em-bee]

yes, you are right. and it makes a lot more sense that way. see my other comment on the difference between commit blob and raw.

[deepsun]

But the path misses param names (or types?). E.g who said the hex-encoded part is a commit hash? Maybe it's a tree hash, or just weird ref.

Query strings are more verbose as force to give each param a name.

[altairprime]

Which target audience of github needs extra verbosity in the commit hash, though? Once you know it you know it; if you don’t know git you aren’t the target audience; etc. Saying /user=foo is no better than ?user=foo if your audience can work it out without confusion from your unadorned paths. We have a great deal of history with filesystems showing that people are capable of keeping up with paths that lack key names if exposed to and familiar with them, and if the filesystem isn’t being constantly randomized.

[deepsun]

> Saying /user=foo is no better than ?user=foo

I mean /foo vs ?user=foo

I know git enough, there's more than one type of hashes -- object hashes, tree hashes.

[iainmerrick]

Back in the day there was an attempt to introduce "matrix URIs" as a more structured alternative to query strings: https://www.w3.org/DesignIssues/MatrixURIs.html

Of course there's nothing to stop you using URIs like this (I think Angular does, or did at one point?) but I don't think the rules for relative matrix URIs were ever figured out and standardised, so browsers don't do anything useful with them.

[em-bee]

what would be a better way of doing that? i am not disagreeing, but i just can't think of any way to improve on this. put everything into the query part? i prefer to use the query only for optional arguments. in this example the blob argument is the only thing that doesn't fit in my opinion.

[arjvik]

Every object in git (commit, tree, revision of a single file) has a hash that is guaranteed unique within a repository (otherwise many more things than a web UI would break) and likely also globally. I can understand wanting to isolate repositories to prevent hash collisions from causing problems, but within a repo everything has a universally unique ID.

edit: for instance, that specific VERBS.md is represented by the blob 3b9a46854589abb305ea33360f6f6d8634649108.

[em-bee]

that's not what i meant. i was trying to suggest that the string "blob" does not fit. why is it there? why is it needed?

    https://github.com/gritzko/beagle/a7e17290a39250092055fcda5ae7015868dabdb4/VERBS.md

this should be sufficient to represent the file.

"blob" is like a descriptor of the value that follows. it would be like doing this:

    https://github.com/user/gritzko/project/beagle/blob/a7e17290a39250092055fcda5ae7015868dabdb4/file/VERBS.md

this actually irks me every time i see it in a github url

[masklinn]

> this should be sufficient to represent the file.

Except it's not, because the oid can be a short hash (https://github.com/gritzko/beagle/blob/a7e172/VERBS.md) and that means you're at risk of colliding with every other top-level entry in the repository, so you're restricting the naming of those toplevel entries, for no reason.

So namespacing git object lookups is perfectly sensible, and doing so with the type you're looking for (rather than e.g. `git` to indicate traversal of the git db) probably simplifies routing, and to the extent that it is any use makes the destination clearer for people reading the link.

[em-bee]

how does adding the word blob in the url help with that?

i don't think it makes a difference here.

in fact compare these urls:

https://github.com/gritzko/beagle/blob/a7e172/VERBS.md

https://github.com/gritzko/beagle/raw/a7e172/VERBS.md

https://github.com/gritzko/beagle/commit/a7e172/VERBS.md

turns out that "blob", "raw" and "commit" have nothing to do with the hash itself, but are functions to describe how the object in question is to be presented. so what i said above about blob being redundant is false, the problem is rather that it is in a weird place. it should be at the end, like a kind of extension because it signifies the format of the output. except i think putting it at the end makes handling relative paths more difficult as it would have to be appended to every link to other files.

the roxen webserver has an interesting solution for that. they call it prestates and it's placed at the beginning of a url: https://github.com/(commit)/gritzko/beagle/a7e172/VERBS.md . it sets the format value visually apart, and you could have multiple prestate values separated by a comma. i have used that feature extensively on my own sites. i even expanded on the concept in custom modules.

[sowbug]

They are following the /key/value/key/value pattern, but the first two pairs in a GitHub URL are fixed to user and project, which lets them omit the key names. I could see them not being willing to hardcode the third pair to blob.

Back when GitHub URLs were kind of cool, github.com/user/gritzko/project/beagle would have been much less cool than just github.com/gritzko/beagle.

[masklinn]

> They are following the /key/value/key/value pattern

They are not. There's just a routing layer below the repository.