Resolving awkward merges

Posted on April 24, 2013 by richo

On my way home tonight I went to ship a feature on groundstation that’d been
hanging around for a while. Lots of work had happened on both sides, and so
when I went to merge it, I was greeted by a LOT of merge conflicts.

First I tried just rebasing it on master, but when that fell over in the same
way I decided to take a new approach. What I did is rougly analogous to a
rebase, with the exception that I didn’t have to lose any history (I’ll end up
with the original commits merged) but I also won’t create a ton of noise in my
logs.

I opened tig with the graph view of my branch and master tig origin/master features/tip_signing,
and then merged each commit by hand.

Having the diff that each commit had on the topic branch makes this easy, even
if the original commit was a PITA.

Once I finished merging, I was left with this monstrosity:


* 5194cc8 (HEAD, master) Merge commit '6e27da1' Richo Healey 8 seconds ago
|\
| * 6e27da1 (origin/features/tip_signing, features/tip_signing) Clean up the input form richo 2 weeks ago
* | 0fbf1f1 Merge commit 'c417108' Richo Healey 2 minutes ago
|\ \
| |/
| * c417108 Border around input bofixupx richo 2 weeks ago
* | d90c150 Merge commit 'a21bca6' Richo Healey 3 minutes ago
|\ \
| |/
| * a21bca6 Clean up styling richo 2 weeks ago
| * 2b4753d Give airship the option of a signing key richo 2 weeks ago
| * 1f0e7f3 Use good/bad colours from bootstrap richo 2 weeks ago
* | c1a0c50 Merge commit '1d4e710' Richo Healey 3 minutes ago
|\ \
| |/
| * 1d4e710 Send signature status to the client properly richo 2 weeks ago
| * 10db7fe Show signature status in the UI richo 2 weeks ago
* | 1d88e3a Merge commit 'f46ac6a' Richo Healey 3 minutes ago
|\ \
| |/
| * f46ac6a Squashed commit of the following: richo 2 weeks ago
* | 7e56994 Merge commit '2fa4d54' Richo Healey 4 minutes ago
|\ \
| |/
| * 2fa4d54 Script to sign grefs richo 2 weeks ago
| * 59d2004 Implement lookup of crypto adaptors richo 2 weeks ago
* | d2dede5 Merge commit '70bcce1' Richo Healey 5 minutes ago
|\ \
| |/
| * 70bcce1 Send signatures with responses in airship richo 3 weeks ago
* | 5de2154 Merge commit 'ce2327c' Richo Healey 7 minutes ago
|\ \
| |/
| * ce2327c Load crypto adaptor on station richo 3 weeks ago
* | aa627f0 Merge commit 'f76d976' Richo Healey 8 minutes ago
|\ \
| |/
| * f76d976 Nuke a ton of dead user code richo 3 weeks ago
| * 0e6e9fb Test deals with untrusted signatures richo 3 weeks ago
| * d4f2b35 Sanely marshall and store signatures richo 3 weeks ago
| * dee7b12 Tests for get signature richo 3 weeks ago
* | 2da7487 Merge commit 'ea46f19632003397a64650a4aa755416288dfcf9' Richo Healey 15 minutes ago
|\ \
| |/
| * ea46f19 Represent tips as (tip, signature) tuples richo 3 weeks ago
* | fb531e2 (origin/master, features/integration-testing/master) Test that we can send objects between nodes Richo
* | 11f6f12 (origin/features/integration-testing/master) Clean up after running tests Richo Healey 4 days ago
* | 2a5fb9a Simple test that stations can connect to one another Richo Healey 4 days ago
* | 73e0a7c Cleanup stream_client Richo Healey 4 days ago
* | ba7172a (features/socket_api) Test station init Richo Healey 2 weeks ago
* | 433ffc1 Bootstrap stations from environment richo 2 weeks ago
* | 2048da0 Merge pull request #23 from richo/bugs/ff-rendering Richo Healey 2 weeks ago

Once you’ve done this merge, you just need the name of the tree (Not the commit!) which you can get from git cat-file -p HEAD, which will emit something like:

tree 2efc6dee9eb621a1e95e88294228456d88d7790f
parent 0fbf1f189dd6d6e155d3e6ccd1750533e31c2d11
parent 6e27da1e890adfff452c3a4b6807d48e15614bc6
author Richo Healey 1366797843 +1000
committer Richo Healey 1366797843 +1000

Merge commit ‘6e27da1’

Now it’s time to construct our “real” merge:

echo "Merge branch 'features/tip_signing'" | git commit-tree -p origin/master -p features/tip_signing 2efc6dee9eb621a1e95e88294228456d88d7790f

This will commit the final tree we arrived at, as a new commit that’s a child
of both master and our topic branch (a merge), but without the messy history.

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Natalya is shutting down

Posted on April 5, 2013 by richo

After a few years of faithful service (Can you believe it’s been 5 years? I just renewed the psych0tik.net domain yesterday. 5 years!) it’s natalya’s time to rest. Ongoing issues with the webhosts, and basically a reshuffle of where I want to spend my hosting budget has led to this.

As far as I know, the only live service depending on this machine is syncvid.info, which will probably either shutdown or be moved elsewhere, but no external disruption is planned. On the offchance you have some dependency we don’t know about- feel free to email staff@psych0tik.net

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Bower is fucked

Posted on March 15, 2013 by richo

Or alternately, front end infrastructure is fucked.

I decided to port groundstation to use bower for it’s frontend assets this evening. Technically, the component in question is airship, but that’s irrelevant. I need to pull in bootstrap, jquery, backbone and a few other bits and pieces and:

  1. It’s a pain in the ass to stay up to date
  2. Having all that code vendored screws with all my metrics

So off to bower land I go!

Cool, I can create a bowerrc with the target directory, and a component.json with some dependencies and run bower install and….

bower error 1 not found

There were errors, here's a summary of them:
- 1 not found

What the fuck is this. Oh, right, I can’t pass an array of dependencies in, it has to be a hash of dependency => version pairs. Cool. Pretty obvious from the error message right?

So I fix that, and run bower install and…

There were errors, here's a summary of them:
- jquery ENOENT, lstat '/Users/richo/.bower/cache/jquery/cf68c4c4e7507c8d20fee7b5f26709d9/.git/tags.3799'

At this point I’m fucking positive they’re just dicking with me. I run the same thing with –debug

There were errors, here's a summary of them:
- jquery ENOENT, lstat '/Users/richo/.bower/cache/jquery/cf68c4c4e7507c8d20fee7b5f26709d9/.git/tags.3799'

Obviously. Then you should see my jaw put a three foot divot in the floor when I notice that all of these commands exited 0.

Through trial and error, I manage to get a bit further to see:

There were errors, here's a summary of them:
- jquery ENOENT, lstat '/Users/richo/.bower/cache/jquery/cf68c4c4e7507c8d20fee7b5f26709d9/.git/tags.22124'
- underscore Didn't get expected byte count
expect: 667648
actual: 847834

and then again my jaw meets floor when I notice that It’s installing these assets anyway.

I’ve already opened a Pull request for the most trivial of these issues but seriously.. come on guys. This isn’t cool.

Chances are significant I’m going to roll my own ghetto make(1) based setup, because at least it does what it says on the tin.

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Explicitly testing race conditions

Posted on February 14, 2013 by richo

This post relates to programming in general, but specifically to Python (because that’s where I’m working at the moment).

I’ve been working on groundstation lately, which leverages git as it’s storage backend, but also assumes that all operations are threadsafe and concurrent. As such, I want to write testcases for it’s internal implementation that actually excercise these race conditions to assert their sanity.

Obviously, I can litter my code with optional callbacks, but that’s pretty much awful. I never thought I’d genuinely wish python had macros or a preprocessor. Do you know of a sane way to approach this?

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Another sleeping experiment

Posted on February 1, 2013 by richo

I’d like to discard time for a week.

This year I’ve decide to embark more on a quest to explore sleep, and the way I experience it personally. It’s something I’ve struggled with as long as I remember, and I figure that by gathering more data points I can at least start to unwind this puzzle.

A few days ago I was considering an experiment, and this post serves as a braindump to flesh out the idea, as well as hopefully a place to gather feedback and ideally hear from someone who’s tried something like this before.

The basic premise is that for a week I’d like to lose the circadian rhythm, sleep when I feel like it and until I wake up naturally, and only afterwards inspect the data.

This has some immediately obvious flaws, the first being that if I’m to lose all perception of time I’d have to black out my house and not go outside. I suspect that by not deliberately structuring my life anything specific this can be overcome.

In more detail, I plan to pull the clock off the devices I own and the interface for the software I’m likely to use in that time (my system taskbar, irssi and tmux all show my timestamps), and use my cli twitter client twat to tweet like a madman, giving my timestamped data points to look at afterwards.

There’s some planning to be done and some preliminary research to be done, but I’m hoping that at the very least it’ll be interesting, even if it serves only as a cautionary tale to others.

Posted in psych0tik News | 2 Comments

NAT Traversal, peer discovery and the stark realisation that you’re an idiot

Posted on January 8, 2013 by richo

In my last post I unveiled groundstation, a supremely pre-beta cut of a tool I’m building to automagically sync objects in several git repos with any and all nearby peers. Up until tonight, I had been testing with two laptops, connected to the same wireless network (more or less the usecase I envisage).

This evening, I had only my laptop with me: but “Not to worry,” I thought, “I’ll just light up my dev VM!”. At work we use vagrant to light up ondemand VM’s, bootstrap them with babushka and get on with it. We use some trickery in the vagrant-dns gem to make the VM addressible from the host, with vagrant taking care of NAT for us.

Which is where things got interesting. groundstation uses UDP broadcast to find it’s peers, which WILL penetrate most NAT configurations, but with the caveat that the source address will be rewritten- in this instance rewriting it to my external IP address, causing my daemon to attempt to connect to it’s “peer” and sync it’s objects- with itself.

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