
Show HN: RewindHN - Go back in Hacker News history - kami8845
http://rewindhn.com/?
======
kami8845
Hey. I built RewindHN.

I created this for the HN community and I'm very happy to see so many people
enjoying it :)

If you have any questions about how I built this or if you'd like to suggest
something new, let me know!

~~~
fudged71
Your app is astoundingly fast. What's your secret?

~~~
kami8845
Buffering [0] and Caching [1].

The front-end specifically asks for pages in 200-chunks. So whether you slide
to page 299,300 or 385, it will request 200-400 from the API. This means I can
then very easily serve these requests out of Redis [1] and during usage
spikes, requests never hit the disk :)

[0]
[https://github.com/doda/rewindhn/blob/master/static/rewind/j...](https://github.com/doda/rewindhn/blob/master/static/rewind/js/main.js#L142)

[1] <https://github.com/doda/rewindhn/blob/master/server.py#L25>

~~~
cheapsteak
Mind if I ask who you're hosting with?

~~~
kami8845
hetzner.de

i7 with 16 gig RAM

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sxp
Nice. I'm also a fan of <http://hnrankings.info/> which is useful to see when
a story has been flagged and suddenly drops off the front page.

~~~
tucson
Interesting one.

I would love to see a list of all the Hacker News "meta tools".

I posted my own last week: <http://www.HnEasy.com> sorts hn all posts and
comments by upvotes from the last day... to last 5 years.

~~~
chris_p
Here's how I see it if I don't resize my window:
<http://i.imgur.com/WeV5K.png>

~~~
tucson
Wow. Thanks for the feedback.

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MehdiEG
Very nice. I actually thought of implementing this a few months ago but a
quick Google search brought up <http://hackerslide.com/> (also open source),
which works fine as well.

~~~
petercooper
Yeah, <http://hackerslide.com/> is mine. This new one has a more precise
interface with the keyboard shortcuts though mine continues to run OK two
years on with no changes. Here's the thread from when it launched which also
topped HN: <http://news.ycombinator.com/item?id=1794614> and I wrote a post
about the reason for putting it together and how it works:
[http://peterc.org/blog/2010/334-hacker-slide-anatomy-
of-a-4-...](http://peterc.org/blog/2010/334-hacker-slide-anatomy-of-a-4-hour-
miniapp.html)

Perhaps one minor bonus to HackerSlide for now is anyone can take the data
collected. The URLs for the JSON archives are formatted like:
<http://hackerslide.com/data/2012-11-01-23.json> (YYYY-MM-DD-HH) although even
better long term are the once a day versions, e.g.:
<http://hackerslide.com/data/2012-11-01.json>

I've learnt two things from this project in particular. First, that most
similar projects don't seem to stick around very long (the Reddit one it was
based on disappeared after a few months as have several others -
<http://hckrnews.com/> is an exception I can recall). Second, these tools seem
to be popular at first but then rarely used over time. Luckily I still find it
useful to catch up after vacations, etc ;-)

~~~
recuter
"Perhaps one minor bonus to HackerSlide for now is anyone can take the data
collected."

Indeed, may I make a suggestion here:

1) Why not make a datadump so people wouldn't need to scrape ~800*24 json
files individually?

2) OP ought to load this data into his version so the timeline goes back
further

3) It seems quite a few people get the urge to tinker like this with HN, I'm
sure pg doesn't mind the scraping, but it strikes me as vastly more efficient
if some sort of shared resource was setup and perhaps added to the footer, in
the vain of HNsearch, so people don't waste time get crawling data setup.

I'm sure somebody else has a dataset just like yours that goes back further
still. :)

Also, thank you for making this and OP for making his. Fun.

~~~
petercooper
_1) Why not make a datadump so people wouldn't need to scrape ~800_ 24 json
files individually?*

Publicly available JSON files was just a side effect of the implementation.
But it's easily to tar and gzip it up, so there's now such a file at
[http://secretshenanigans.s3.amazonaws.com/hnfrontpages.tar.g...](http://secretshenanigans.s3.amazonaws.com/hnfrontpages.tar.gz)
(32MB).

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earlyriser
I really like the UX. I implemented something like this some years ago for HN
and other sites, but not as granular, at <http://rrrewind.com>

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Goopplesoft
Nice. I made something like this for reddit called redditrewind:
<http://www.redditrewind.com>

~~~
chris_p
That's awesome, but I don't like the UI. A slider would be nice!

~~~
Goopplesoft
We had a slider at one point, we thought it wasn't as good as this method. Ill
look back into the options soon.

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clockwork_189
This looks amazing! Good job! If I may ask(yes I have taken a look at your
code but unfortunately my python is not too good), whats the "secret" to
grabbing HN's historic data? Also, would it be possible to go back beyond one
month towards maybe a year or even few years back (idk if it is just me but I
can go up until October 9th, 2012)?

Thanks!

~~~
kami8845
<https://github.com/doda/rewindhn/blob/master/scrape.py#L26>

This is where the scraping happens. The code is a little uglier than I'd like,
but that's largely to do with the hard-extract-data from HN markup. I'll look
at adding more data soon.

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klous
There was something very similar to this for reddit that was very handy and
useful. It was at redditsnapshot.sweyla.com but it shut down at some point. I
still think there is an opportunity for someone to index reddit's front page
and have it hour by hour and maybe a premium version of all the subreddits you
subscribe to.

~~~
kahoon
When I saw that sweylas's stuff has disappeared, I asked them in an email if
it will be back again. I didn't get an answer so I implemented my own version:
<http://redditsnapshots.com/> (running since March 2012)

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mannjani
Awesome. One can also use it to analyse various trends on HN. For ex. look at
this story: <http://news.ycombinator.com/item?id=4739649> from November 4th
6:40 pm to 11:00 pm. Shows you how HN'ers are eager to help each other.

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EGreg
Great work! Please try to change control-arrows to something else, as Macs map
it to switching desktops :)

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dotmanish
Loved this. I would love the feature where I could "highlight" (add a glow for
effect) any particular story and watch it move up and down as I play with the
arrows. Right now everything moves, so this would help spot trend for a
particular story.

All in all, Awesome.

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vasco
This is awesome, and really well done. The keyboard bindings are very handy.
Would be great if it had older snapshots.

~~~
kami8845
That's a good idea! I'll look at incorporating some "historic" snapshots from
archive.org

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samwilliams
Great idea! The left and right arrow key functionality doesn't appear to be
working for me though (FF 16, Fedora 17).

~~~
kami8845
Hm. That's weird. I'm using <http://github.com/madrobby/keymaster> to hook up
the keys to the same function also used by the slider itself.

Does the keymaster live demo at <http://madrobby.github.com/keymaster/> work
for you?

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nikunjk
Blown away on how fast this website is. I kept the left arrow key pressed and
it didn't shutter once.

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highace
Awesome. How about animating it so you can see the posts actually moving up
and down?

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d0m
I'm ashamed to say I had _too much_ already visited links in the past months..

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eande
Great work! Typing date/time directly would be a nice extra feature.

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Nux
Doesn't show ANYTHING without javascript....

~~~
kami8845
Ha, you're right. I just put up a notice for <noscripters>

~~~
Nux
lol! Don't do that, show some real content instead. :-)

~~~
d0m
Seems like there's an API if you want to get some datas out of it. Otherwise,
you might want to try to use javascript on trusted websites.. it actually
often enhance the pages.

~~~
Nux
How do I know a web site is trusted?

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egze
This is awesome!

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donebizkit
Good one kami

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celalo
very well done. ux is great.

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levlandau
Very nice

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zapt02
Very cool!

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codegeek
works great. I love it.

