HN Explorer

Show HN: Daylight – track sunrise / sunset times in your terminal (github.com)

79 points by jbreckmckye ↗ HN
I love the sunlight and dread the long, dark winter evenings of Northern Europe. I often look up sunrise / sunset times and count off the days until the darkness is gone.

Now I've written a terminal app for this (Mac/Linux)

Features: a colorful summary of daylight times for your location; projected change over the coming days; handles NO_COLOR and a ---short flag if you dislike the output format.

The location is IP-based but you can override this if you're on a VPN. Just create a terminal alias with the --loc flag. The app supports areas in the arctic / antarctic circle too.

Check our the repository for a preview and instructions on how you can install it with Homebrew.

(There is a Windows build but it's not yet tested)

20 comments

[ 4.7 ms ] story [ 65.0 ms ] thread
[deleted]
(comment deleted)
japaget
Windows build works fine (Windows 10 Professional x64 22H2).
jbreckmckye
Thanks! (Don't have a Windows machine right now so that's very helpful)
rrr_oh_man
Great looking app!!

I immediately checked how you do location lookups:

> IP lookup is powered by https://ipinfo.io. They provide a good service so please don't spam requests.

There was a thread about them recently — the scale of their operation was very surprising.

jbreckmckye
It _is_ possible to use native OS APIs for location lookup, but these all seem to rely on cgo. Which was a bit intimidating for a "let's learn Golang" project

(Probably not the nicest code and no doubt I've broken a lot of Go idioms, but it was a good learning exercise)

IPInfo is a good service and their developer relations were surprisingly relaxed about me (mis)using their API this way

reincoder
"Surprisingly relaxed," you say. Let me tell you about the time our users reverse-engineered our apps, submitted 2.2 million IPs, and broke our systems for our hackathon.

https://ipinfo.io/blog/ipinfos-ip-hunt-2-2-million-ips-submi...

This is just our user base, to be honest and we like them for their mindset. We are happy to see users try our service in different ways and we learn a ton from them in that process. I certainly learned from you :)

reincoder
Thank you very much! I appreciate talking with you in the other thread! I told the repo owner not to worry about "spamming" our service. We are happy to support as many requests as people can throw at us.

Internally, when it comes to API requests, we are doing our best to reach an "unlimited" level of API requests. On the operational side, we are just getting started. The distributed network of a thousand servers we operate only runs a handful of diagnostic tests (ping, traceroute, etc.).

We have a lot of plans, and I hope you will find us providing more fun stuff as we continue to grow!

thenthenthen
Cool! Can we use the sky hue as Terminal background or overal “theme”?
ndegruchy
Of course, you can get this information in Emacs, too. You'll need to get your lat and long, first:

    (setq calendar-latitude  12.3456
          calendar-longitude -98.7654)
Then, you can `M-x sunrise-sunset` and see the times (and total daylight hours) in the echo area.
jrootabega
Is the noon color scheme supposed to look like Finn from Adventure Time?
voidUpdate
Does this pull the times from an online service or are they calculated locally? I tried to read the code to work it out but I don't program in Go so I got a little lost
jbreckmckye
It gets your latitude/longitude from an IP lookup service, then does a geometric calculation locally
jmholla
Is there a configuration file or command line option to provide location information manually?
jbreckmckye
Yes, you can use `--loc="12.34,56.78"` where the values are longitude and latitude.

You can also override the Timezone with `--timezone` (passing an IANA timezone e.g. America/New_York).

kseistrup
This is nice, I like it!

Is there a way to make it use 24h time, rather than AM/PM?

kseistrup
If I use e.g. `daylight --timezone=Europe/Copenhagen` it does actually show the 24h times, which is nice. But til still appends AM/PM, which is kind of weird. :)
JimmyDeep
I live in a place where it often rains, and I really love sunny weather. It makes me feel a bit down when I see that it's already dark by the time I get off work. I was wondering, since the Earth's revolution is taken into account, the time you get should be different every day, right?