11 Commits

Author SHA1 Message Date
Ben Busby
8ce5b04f51
Install crontab w/ script
This adds a couple of new scripts: install-crontab.sh and update.sh. The
install-crontab script does exactly that -- it installs a new crontab
that runs the update script every 5 minutes. An update script was added
to simplify the crontab a bit and to ensure the Elixir update script is
executed from the correct directory.
2021-11-15 16:44:26 -07:00
Ben Busby
8ee4f308a4
Prevent same instance from being selected twice in a row
Introduces a new db key "<service>-previous" to track which instance was
last selected for a particular service. This allows for filtering the
list of available instances to exclude the instance that was last
picked, to ensure a (slightly) more even distribution of traffic.
There's still the possiblity of the following scenario, however:

:service instances > 2

/:service request #1 -> instance #1
/:service request #2 -> instance #2
/:service request #3 -> instance #1
/:service request #4 -> instance #2

where there are many ignored instances for a particular service. One
possible solution would be to implement the "<service>-previous" value
to be a list, rather than a single value, and push to that list until
only one element is left in the original "instance" array after
filtering, and then delete the "<service>-previous" key.
2021-11-10 12:19:37 -07:00
Ben Busby
d334fc7695
Move Service struct def to its own module
Service struct now defined in lib/service.ex

This makes a bit more sense now that its a shared resource, rather than
just defining it only in the update.exs script.
2021-11-10 11:48:39 -07:00
Ben Busby
39c244d970
Skip querying all instances w/ "test mode"
Now allows setting FARSIDE_TEST to skip individually fetching each
instance, and instead just adds all of them to redis instantly. This
allows for an easier time in CI builds, for both the sake of speed and
to prevent a scenario where many simultaneous builds have a noticeable
impact on actual instances.
2021-11-09 15:12:58 -07:00
Ben Busby
56b9c52528
Display list of available instances on home page
This introduces a number of new changes:
- Services are now inserted into redis with a prefix prepended to the
key name. This allows for easier filtering to get only live instances.
- The home page now uses an eex template for displaying all live
instances for every service, determined by the last update
- A "last_updated" field was added
- farside.ex was added to contain all functionality related to querying
for instances (WIP)
- Other improvements
2021-11-08 17:08:19 -07:00
Ben Busby
8042dcad0c
Refactor project to new name
The name of the project is being refactored from Privacy Revolver to
Farside. The reasoning behind this is:
1. A shorter name is easier to remember
2. It can stand for "FOSS alternative redirecting service" (which I know
doesn't encapsulate all letters from "farside", but it's close enough).

This commit also includes improvements to the update script for
determining how far along the script is.
2021-11-07 12:29:06 -07:00
Ben Busby
76faebd234
Move constants to config, update string formatting
Not sure if this is the Elixir-y way to do this, but seems more logical
than hardcoding values such as redis connection.

Also went through and improved how string formatting was performed
throughout the app. Rather than "combining" <> "strings" this way, I'm
now just doing "#${variable}#{formatting}", which looks a lot cleaner.
2021-10-22 20:07:07 -06:00
Ben Busby
edcab37c7d
Write results of update script to file for debugging
The update script now writes the available instances to a
.update-results* file (where previous runs have "-prev" appended to the
file name). This helps to see how instance availability changes between
runs of the script when debugging overall functionality of the app.
2021-10-22 18:07:59 -06:00
Ben Busby
4949ae22bb
Output available instances and fallback URL to redis
Once a list of available URLs has been determined for a particular
service, the list is written as "service -> [list of instances]" to a
local redis connection. These can then be used in the greater routing
logic to pick a random instance from the list, or use a fallback
instance if none are determined to be available.
2021-10-22 17:15:40 -06:00
Ben Busby
b0953f0777
Validate status code for all service instances
Updated to filter out all instances that either time out (I believe
default timeout for HTTPoison is 5s) or return a non-200 status code.
2021-10-21 21:15:58 -06:00
Ben Busby
cf8dfc5a85
Initialize update script
My initial thought for this: create a simple redis db for storing key
value pairs of instance -> list of live instances for each privacy front
end (libreddit, bibliogram, etc). A script executed on a certain
schedule would (in the background) check each instance to make sure it
isn't down or unreasonably slow. If the instance is available, add it to
a list of available instances in the db.

When a user navigates to the revolver url (something like
<url>/<service>/<...>), the app would pick a random value from the list
returned by redis.get('<service>') and forward the user to that
instance.

As a side note, this could instead load the instances json from a remote
source (like github or something) so that changes to instances don't
need to involve a redeploy of the entire app.
2021-10-21 17:07:43 -06:00