threads / discuss / 58566

issue with submodules using origin remote unexpectadly

Subject: issue with submodules using origin remote unexpectadly

## tl;dr

5 messages between Oct 4, 2022 and Oct 12, 2022.

replies: 4people: 2as markdown or json

Jacob Keller· Oct 4, 2022, 17:43 UTC · lore
Hi,

I've been running into an issue with submodules trying to fetch using "origin" even though the submodule does not have a remote by that name. (I recently switched the submodule remote name)

remote: Enumerating objects: 210, done.
remote: Counting objects: 100% (207/207), done.
remote: Compressing objects: 100% (54/54), done.
remote: Total 210 (delta 123), reused 197 (delta 119), pack-reused 3
Receiving objects: 100% (210/210), 107.20 KiB | 4.29 MiB/s, done.
Resolving deltas: 100% (123/123), completed with 48 local objects.
From <redacted>
...
Fetching submodule submodule
From <redacted>
   85e0da7533d9..80cc886f1187  <redacted>
Fetching submodule submodule2
fatal: 'origin' does not appear to be a git repository
fatal: Could not read from remote repository.
Please make sure you have the correct access rights
and the repository exists.
Errors during submodule fetch:
        submodule2

I thought at first there might be some configuration value in the parent that is selecting origin, but I can 't find one. I also thought maybe its some sort of defaulting to origin but I looked through submodule code and didn't find one.

Is it just that submodule code is not resilient against changing the default remote name away from origin?

Thanks, Jake

Glen Choo· Oct 4, 2022, 18:12 UTC · re: Jacob Keller · lore

Re: issue with submodules using origin remote unexpectadly

Hi Jacob! Thanks for the report!
I think we'd need a bit more info, specifically:
- How did you rename the remote?
- What command is doing the submodule fetch?

Or, if you could include a reproduction script, that would be really helpful :)

Jacob Keller <jacob.keller@gmail.com> writes:
Show 5 quoted lines
> Hi,
>
> I've been running into an issue with submodules trying to fetch using
> "origin" even though the submodule does not have a remote by that
> name. (I recently switched the submodule remote name)

How did you rename the remote? e.g. did you run `git remote rename`, or did you rename it manually? I'll come back to why this might be important...

Show 20 quoted lines
>
> remote: Enumerating objects: 210, done.
> remote: Counting objects: 100% (207/207), done.
> remote: Compressing objects: 100% (54/54), done.
> remote: Total 210 (delta 123), reused 197 (delta 119), pack-reused 3
> Receiving objects: 100% (210/210), 107.20 KiB | 4.29 MiB/s, done.
> Resolving deltas: 100% (123/123), completed with 48 local objects.
> From <redacted>
> ...
> Fetching submodule submodule
> From <redacted>
>    85e0da7533d9..80cc886f1187  <redacted>
> Fetching submodule submodule2
> fatal: 'origin' does not appear to be a git repository
> fatal: Could not read from remote repository.
>
> Please make sure you have the correct access rights
> and the repository exists.
> Errors during submodule fetch:
>         submodule2
I assume this is `git fetch` running in the superproject?
Show 7 quoted lines
> I thought at first there might be some configuration value in the
> parent that is selecting origin, but I can 't find one. I also thought
> maybe its some sort of defaulting to origin but I looked through
> submodule code and didn't find one.
>
> Is it just that submodule code is not resilient against changing the
> default remote name away from origin?

Yes, in a sense, though I'm not sure if this is the source of your problems.

When fetching with `git fetch`, submodules are fetched without specifying the remote name, which means Git guesses which remote you want to fetch from, which is documented at https://git-scm.com/docs/git-fetch. I believe (I haven't reread this very closely) this is, in order:

- The remote of your branch, i.e. the value of the config value
  `branch.<name>.remote`
- origin

This is why `git remote rename` matters, because `git remote rename` will also rename `branch.<name>.remote`. If you have a branch checked out in your submodule, you might want to double-check your .git/config.

But... I'll mention another wrinkle for completeness' sake (though I don't think it applies to you). If you fetch using `git submodule update`, the submodule is fetched using a _named_ remote, specifically:

- If the superproject has a branch checked out, it uses the name of the
  superproject branch's remote.
- If the superproject does not have a branch checked out, it uses
  "origin".
>
> Thanks,
> Jake
Jacob Keller· Oct 11, 2022, 21:15 UTC · re: Glen Choo · lore

Re: issue with submodules using origin remote unexpectadly

On Tue, Oct 4, 2022 at 11:12 AM Glen Choo <chooglen@google.com> wrote:
>
> Hi Jacob! Thanks for the report!
>
Thanks for responding!
Show 5 quoted lines
> I think we'd need a bit more info, specifically:
>
> - How did you rename the remote?
> - What command is doing the submodule fetch?
>

I am doing a git pull --rebase in the superproject, and I renamed the remote in the submodule using git remote rename.

> Or, if you could include a reproduction script, that would be really
> helpful :)
>

I'm not sure how to do this, because it is only an intermittent failure. I suspect it has to do with when the submodule actually needs to update.

Perhaps I can come up with something though. If I can, I'll send it as a new test.

Show 12 quoted lines
> Jacob Keller <jacob.keller@gmail.com> writes:
>
> > Hi,
> >
> > I've been running into an issue with submodules trying to fetch using
> > "origin" even though the submodule does not have a remote by that
> > name. (I recently switched the submodule remote name)
>
> How did you rename the remote? e.g. did you run `git remote rename`, or
> did you rename it manually? I'll come back to why this might be
> important...
>
I renamed it using git remote rename.
Show 23 quoted lines
> >
> > remote: Enumerating objects: 210, done.
> > remote: Counting objects: 100% (207/207), done.
> > remote: Compressing objects: 100% (54/54), done.
> > remote: Total 210 (delta 123), reused 197 (delta 119), pack-reused 3
> > Receiving objects: 100% (210/210), 107.20 KiB | 4.29 MiB/s, done.
> > Resolving deltas: 100% (123/123), completed with 48 local objects.
> > From <redacted>
> > ...
> > Fetching submodule submodule
> > From <redacted>
> >    85e0da7533d9..80cc886f1187  <redacted>
> > Fetching submodule submodule2
> > fatal: 'origin' does not appear to be a git repository
> > fatal: Could not read from remote repository.
> >
> > Please make sure you have the correct access rights
> > and the repository exists.
> > Errors during submodule fetch:
> >         submodule2
>
> I assume this is `git fetch` running in the superproject?
>

Its git pull --rebase, but I suppose as part of this it will run something equivalent to git fetch?

Show 11 quoted lines
> > I thought at first there might be some configuration value in the
> > parent that is selecting origin, but I can 't find one. I also thought
> > maybe its some sort of defaulting to origin but I looked through
> > submodule code and didn't find one.
> >
> > Is it just that submodule code is not resilient against changing the
> > default remote name away from origin?
>
> Yes, in a sense, though I'm not sure if this is the source of your
> problems.
>
Hmm.
Show 8 quoted lines
> When fetching with `git fetch`, submodules are fetched without
> specifying the remote name, which means Git guesses which remote you
> want to fetch from, which is documented at
> https://git-scm.com/docs/git-fetch. I believe (I haven't reread this
> very closely) this is, in order:
>
> - The remote of your branch, i.e. the value of the config value
>   `branch.<name>.remote`

So basically if its checked out to a branch it will fetch from the remote of that branch, but...

> - origin
>

It defaults to origin, so if you have the usual "checked out as a detached head" style of submodule, it can't find the remote branch.

> This is why `git remote rename` matters, because `git remote rename`
> will also rename `branch.<name>.remote`. If you have a branch checked
> out in your submodule, you might want to double-check your .git/config.
>

I do not have a branch checked out, I have it checked out as detached head, as is the usual style for "git submodule update" would do.

Show 6 quoted lines
> But... I'll mention another wrinkle for completeness' sake (though I
> don't think it applies to you). If you fetch using `git submodule
> update`, the submodule is fetched using a _named_ remote, specifically:
>
> - If the superproject has a branch checked out, it uses the name of the
>   superproject branch's remote.

Right, so that explains why I can re-run git submodule update after a git pull --rebase and it works.

In theory wouldn't it make more sense to use the remote based on the URL of the .gitmodules file?

> - If the superproject does not have a branch checked out, it uses
>   "origin".
>

I suppose one option would be to make this configurable. I started using "upstream" as the default remote name for most of my repositories when I began working with forks a lot more.

> >
> > Thanks,
> > Jake
Glen Choo· Oct 11, 2022, 22:20 UTC · re: Jacob Keller · lore

Re: issue with submodules using origin remote unexpectadly

Jacob Keller <jacob.keller@gmail.com> writes:
Show 6 quoted lines
> On Tue, Oct 4, 2022 at 11:12 AM Glen Choo <chooglen@google.com> wrote:
>>
>> Hi Jacob! Thanks for the report!
>>
>
> Thanks for responding!
:) 
Show 10 quoted lines
>> Or, if you could include a reproduction script, that would be really
>> helpful :)
>>
>
> I'm not sure how to do this, because it is only an intermittent
> failure. I suspect it has to do with when the submodule actually needs
> to update.
>
> Perhaps I can come up with something though. If I can, I'll send it as
> a new test.
That would be greatly appreciated, thanks!
If you find code pointers useful,
- builtin/submodule--helper.c:fetch_in_submodule() contains the logic
  for fetching during "git submodule update"
- submodule.c:fetch_submodules() contains the logic for fetching during
  "git fetch --recurse-submodules" (which is invoked by "git pull
  --recurse-submodules").
Show 26 quoted lines
>> >
>> > remote: Enumerating objects: 210, done.
>> > remote: Counting objects: 100% (207/207), done.
>> > remote: Compressing objects: 100% (54/54), done.
>> > remote: Total 210 (delta 123), reused 197 (delta 119), pack-reused 3
>> > Receiving objects: 100% (210/210), 107.20 KiB | 4.29 MiB/s, done.
>> > Resolving deltas: 100% (123/123), completed with 48 local objects.
>> > From <redacted>
>> > ...
>> > Fetching submodule submodule
>> > From <redacted>
>> >    85e0da7533d9..80cc886f1187  <redacted>
>> > Fetching submodule submodule2
>> > fatal: 'origin' does not appear to be a git repository
>> > fatal: Could not read from remote repository.
>> >
>> > Please make sure you have the correct access rights
>> > and the repository exists.
>> > Errors during submodule fetch:
>> >         submodule2
>>
>> I assume this is `git fetch` running in the superproject?
>>
>
> Its git pull --rebase, but I suppose as part of this it will run
> something equivalent to git fetch?

Unfortunately, this doesn't narrow it down much because "git pull --recurse-submodules" runs _both_ "git fetch --recurse-submodules" _and_ "git submodule update [--rebase]" ;) Without more context, it's not clear which of those is failing.

Show 17 quoted lines
>> When fetching with `git fetch`, submodules are fetched without
>> specifying the remote name, which means Git guesses which remote you
>> want to fetch from, which is documented at
>> https://git-scm.com/docs/git-fetch. I believe (I haven't reread this
>> very closely) this is, in order:
>>
>> - The remote of your branch, i.e. the value of the config value
>>   `branch.<name>.remote`
>
> So basically if its checked out to a branch it will fetch from the
> remote of that branch, but...
>
>> - origin
>>
>
> It defaults to origin, so if you have the usual "checked out as a
> detached head" style of submodule, it can't find the remote branch.

Yes, this sounds about right. I was quite certain that we only default to "origin", but I observe that "git fetch" doesn't fail if there is only one remote and it is not named "origin". Perhaps I'm mistaken, or I simply couldn't track down that logic.

Show 12 quoted lines
>> But... I'll mention another wrinkle for completeness' sake (though I
>> don't think it applies to you). If you fetch using `git submodule
>> update`, the submodule is fetched using a _named_ remote, specifically:
>>
>> - If the superproject has a branch checked out, it uses the name of the
>>   superproject branch's remote.
>
> Right, so that explains why I can re-run git submodule update after a
> git pull --rebase and it works.
>
> In theory wouldn't it make more sense to use the remote based on the
> URL of the .gitmodules file?

Ah, yes that's one possibility we (the folks working on an improved Submodules UX) have considered. Another would be to teach submodules to actually use branches correctly and to use the remotes of the branches.

In general, the project tries not to respect config coming directly from .gitmodules (c.f. [1]), but I agree that there's a lot of room for improvement.

[1] https://lore.kernel.org/git/xmqq35bze3rr.fsf@gitster.g
Show 7 quoted lines
>> - If the superproject does not have a branch checked out, it uses
>>   "origin".
>>
>
> I suppose one option would be to make this configurable. I started
> using "upstream" as the default remote name for most of my
> repositories when I began working with forks a lot more.

My hope is that the work I mentioned earlier makes this code obsolete and nobody ever has to configure this ;)

>
>> >
>> > Thanks,
>> > Jake
Jacob Keller· Oct 12, 2022, 00:13 UTC · re: Glen Choo · lore

Re: issue with submodules using origin remote unexpectadly

On Tue, Oct 11, 2022 at 3:20 PM Glen Choo <chooglen@google.com> wrote:
Show 34 quoted lines
>
> Jacob Keller <jacob.keller@gmail.com> writes:
>
> > On Tue, Oct 4, 2022 at 11:12 AM Glen Choo <chooglen@google.com> wrote:
> >>
> >> Hi Jacob! Thanks for the report!
> >>
> >
> > Thanks for responding!
>
> :)
>
> >> Or, if you could include a reproduction script, that would be really
> >> helpful :)
> >>
> >
> > I'm not sure how to do this, because it is only an intermittent
> > failure. I suspect it has to do with when the submodule actually needs
> > to update.
> >
> > Perhaps I can come up with something though. If I can, I'll send it as
> > a new test.
>
> That would be greatly appreciated, thanks!
>
> If you find code pointers useful,
>
> - builtin/submodule--helper.c:fetch_in_submodule() contains the logic
>   for fetching during "git submodule update"
>
> - submodule.c:fetch_submodules() contains the logic for fetching during
>   "git fetch --recurse-submodules" (which is invoked by "git pull
>   --recurse-submodules").
>

I was able to get a test highlighting the failure. It shows the case of a single remote working but adding another remote causes it to fail as it falls back to the 'origin'.

Show 33 quoted lines
>
> >> >
> >> > remote: Enumerating objects: 210, done.
> >> > remote: Counting objects: 100% (207/207), done.
> >> > remote: Compressing objects: 100% (54/54), done.
> >> > remote: Total 210 (delta 123), reused 197 (delta 119), pack-reused 3
> >> > Receiving objects: 100% (210/210), 107.20 KiB | 4.29 MiB/s, done.
> >> > Resolving deltas: 100% (123/123), completed with 48 local objects.
> >> > From <redacted>
> >> > ...
> >> > Fetching submodule submodule
> >> > From <redacted>
> >> >    85e0da7533d9..80cc886f1187  <redacted>
> >> > Fetching submodule submodule2
> >> > fatal: 'origin' does not appear to be a git repository
> >> > fatal: Could not read from remote repository.
> >> >
> >> > Please make sure you have the correct access rights
> >> > and the repository exists.
> >> > Errors during submodule fetch:
> >> >         submodule2
> >>
> >> I assume this is `git fetch` running in the superproject?
> >>
> >
> > Its git pull --rebase, but I suppose as part of this it will run
> > something equivalent to git fetch?
>
> Unfortunately, this doesn't narrow it down much because "git pull
> --recurse-submodules" runs _both_ "git fetch --recurse-submodules" _and_
> "git submodule update [--rebase]" ;) Without more context, it's not
> clear which of those is failing.
>
It's definitely "git fetch --recurse-submodules", the new test should show this.
Show 23 quoted lines
> >> When fetching with `git fetch`, submodules are fetched without
> >> specifying the remote name, which means Git guesses which remote you
> >> want to fetch from, which is documented at
> >> https://git-scm.com/docs/git-fetch. I believe (I haven't reread this
> >> very closely) this is, in order:
> >>
> >> - The remote of your branch, i.e. the value of the config value
> >>   `branch.<name>.remote`
> >
> > So basically if its checked out to a branch it will fetch from the
> > remote of that branch, but...
> >
> >> - origin
> >>
> >
> > It defaults to origin, so if you have the usual "checked out as a
> > detached head" style of submodule, it can't find the remote branch.
>
> Yes, this sounds about right. I was quite certain that we only default
> to "origin", but I observe that "git fetch" doesn't fail if there is
> only one remote and it is not named "origin". Perhaps I'm mistaken, or I
> simply couldn't track down that logic.
>

We definitely default to the single/lone remote, I have two tests, one which shows the single remote working and another which shows the additional remote causing the failure.

Show 17 quoted lines
> >> But... I'll mention another wrinkle for completeness' sake (though I
> >> don't think it applies to you). If you fetch using `git submodule
> >> update`, the submodule is fetched using a _named_ remote, specifically:
> >>
> >> - If the superproject has a branch checked out, it uses the name of the
> >>   superproject branch's remote.
> >
> > Right, so that explains why I can re-run git submodule update after a
> > git pull --rebase and it works.
> >
> > In theory wouldn't it make more sense to use the remote based on the
> > URL of the .gitmodules file?
>
> Ah, yes that's one possibility we (the folks working on an improved
> Submodules UX) have considered. Another would be to teach submodules to
> actually use branches correctly and to use the remotes of the branches.
>

Yes, if we can have it checkout on a branch and just rewind that branch to match the expected commit instead of having it in a detached state, things would be much easier. I recall work being done on this years ago, but it is quite a thorny problem.

> In general, the project tries not to respect config coming directly from
> .gitmodules (c.f. [1]), but I agree that there's a lot of room for
> improvement.
>

Right. I think I'd rather go with a config option inside the .git/config [submodule] section. I don't think gitmodules itself needs to know this, just that the parent project could be informed of what remote to default to when fetching inside the submodule. That or somehow unify the git submodule update code with the recursive fetching?

Show 13 quoted lines
> [1] https://lore.kernel.org/git/xmqq35bze3rr.fsf@gitster.g
>
> >> - If the superproject does not have a branch checked out, it uses
> >>   "origin".
> >>
> >
> > I suppose one option would be to make this configurable. I started
> > using "upstream" as the default remote name for most of my
> > repositories when I began working with forks a lot more.
>
> My hope is that the work I mentioned earlier makes this code obsolete
> and nobody ever has to configure this ;)
>

Yea. I definitely like the idea of using branches instead of a detached head state.

I think for now I can avoid this by just disabling recursive fetch in my config, which at least gets around the problem well enough.

Another alternative I thought was maybe "try to fetch every remote" instead of trying to fetch only a single remote?

> >
> >> >
> >> > Thanks,
> >> > Jake

← back to recent threads