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I've been using Fossil for quite a while now as my SCM. I like Fossil. But Fossil is not Git, and most people seem to like Git. It could be better to say that most people like GitHub because it's the first hosted SCM that's free for open source with good social interaction I'm aware of. And GitHub is huge. Some might say that if you're not on GitHub, you don't exist as a project. Well this obviously isn't true, but you get the idea. You can get free Fossil hosting at Chisel, which is nice, but it's also not GitHub. Plus I like to be 100% self hosted.

So, to get myself on GitHub (as a mirror only), there needs to be a bridge between Fossil and Git. Fossil documentation implies this is quite easy. Sadly, this isn't the case as the <=Fossil-1.37 releases (note there is no guaranntee that future versions of follow will not have these flaws - my branch may not be comitted to trunk) have the following flaws:

  • Branch and Tag name mangling (dhcpcd-6 becomes dhcpcd_6)
  • Silent master branch renaming into trunk on inport, but not on export
  • No tag comments (Fossil lacks the feature) which means syncing tags back and forth results in tag conflict due to signature change

I submitted some initial patches the the Fossil mailing list and I now have a Fossil commit bit! You can find my branch here to fix the Fossil Git bridge.

But that's not the end of the story. A bridge has two ends. With my initial setup, the Git end was bare bones repository which I pushed to GitHub. This is no longer the case - I now need a staging repository to pull both ends. And this requires a script because Git needs a little more hand-holding to completely track a remote. The below script is tailored for my needs, yours may differ. It also reflects the above initial design and the subsequent change - as such it it may need editing if you need to create a git clone from fossil. This comes with no support, just as an idea of how you might implement such a bridge.

#!/bin/sh

fossildir=/var/fossil
# Cannot be a bare directory for git as we cannot write to the host directly.
# So we have a staging directory instead.
# This requires a bit of hand-holding to track all the branches.
gitdir=/var/git-staging

marksdir=/var/scm-marks

# Respect default naming at either end
fossil_export_opts="--rename-trunk master"
fossil_import_opts="--rename-master trunk"

# Only used when creating a git bare bones repo from Fossil.
export_fossil_to_git_new()
{

        rm -f "$fossilmarks" "$gitmarks"
        git init
        fossil export --git \
                --export-marks "$fossilmarks" \
                $fossil_export_opts "$fossildir/$fossilrepo" | \
                git fast-import \
                --export-marks="$gitmarks"
}

export_fossil_to_git()
{

        fossil export --git \
                --import-marks "$fossilmarks" --export-marks "$fossilmarks" \
                $fossil_export_opts "$fossildir/$fossilrepo" | \
                git fast-import \
                --import-marks="$gitmarks" --export-marks="$gitmarks"
}

export_git_to_fossil()
{

        git fast-export --all \
                --import-marks="$gitmarks" --export-marks="$gitmarks" | \
                fossil import --git --incremental \
                --import-marks "$fossilmarks" --export-marks "$fossilmarks" \
                $fossil_import_opts "$fossildir/$fossilrepo"
}

pull_git()
{
        local remote

        git fetch --all
        # Track all remote branches
        git branch -r | grep -v '\->' | while read remote; do
                if [ -z "$(git branch --list "${remote#origin/}")" ]; then
                        git branch --track "${remote#origin/}" "$remote"
                fi
        done
        git branch --list | sed -e 's/^\* //' | while read branch; do
                git checkout "$branch"
                git merge --ff-only
        done
}

push_git()
{

        git push --all
        git push --tags
        # Reset the current branch checkout.
        # If we don't, the next run will complain about unstashed changes.
        # This maybe a bug in git, but maybe not because the live checkout
        # *is* behind at this point as we just fast-imported.
        git reset --hard
}

echo "Syncing git and fossil."
for repo in "$fossildir"/*.fossil; do
        fossilrepo=${repo#${fossildir}/*}
        repo=${fossilrepo%.fossil}
        gitrepo="$repo"
        fossilmarks="$marksdir/$repo.fossil.marks"
        gitmarks="$marksdir/$repo.git.marks"

        # We just sync old fossil repos to new phab clones
        if [ -d "$gitdir/$gitrepo" ]; then
                cd "$gitdir/$gitrepo"
                pull_git # staging only
                export_git_to_fossil
                export_fossil_to_git
                push_git # staging only
# Enable the below if pusing to a bare git repo from fossil
#       else
#               export_fossil_to_git_new
        fi
done

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So finally I've moved all services from my old server to my Christmas Xen box! This was not without problems due to the fact it had to run NetBSD -current

  • gcc toolchain is broken for some packages which affected running any PHP build
  • clang toolchain was broken for my config (USE_SSP= yes and CPUFLAGS+= -march=core2)
  • clang compiles as a whole were broken due to a recent efiboot import

In hind-sight, I could have had the box up and running a lot sooner if I used NetBSD-7 guests (or maybe just a NetBSD-7 build box), but no, I just had to get -current running. It offers more than -7 and prior exerience told me that tracking -7 was very problematic ... but that could have been due to my settings and wanting to compile everything with clang. I've currently got 3 -current images there now ... the Xen DOM0, the actual server itself as Xen DomU (without any compiler or tools) and another Xen DomU which just builds stuff for other guests to use.

Anyway, the box itself is now up and running and all relevant services have been moved to it. During this move, I decided to modernise things a little and setup HTTP/2. If you're reading this then it's working :) As such, I've re-directed all basic HTTP traffic to HTTPS and it does seem to load a lot faster. One side effect of this is that I've stoped using my own self signed certificates and I'm now using the nice Let's Encrypt service. pkgsrc users should use the py-certbot package and don't bother searching for any letsencrypt package as it's been renamed. I found this quite confusing as there was no reference to the rename in pkgsrc I could find and wasted a little time on it.

But now it's live I can finally look into bringing online some other development utilities to play around with as the server has a lot more room to grow :)

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