The are several reasons

• One configuration for all Http calls

For now we need to implement a simple class that sends data to user's email (mailinator for now). Email other configurations will be added later

Currently the app sends only names and magnitudes as HTML list. This should be revised.

Heavens-Above allows to send additional query parameters to specify user's geo data. Here is an example

https://www.heavens-above.com/Comets.aspx?lat=56.8666&lng=53.2094&loc=Izhevsk&alt=0&tz=SAMT

It should be adapted in the client too

If there are a lot of subscribers, it can take a big amount of time to send them in scope of one method call. Probably it should be done asynchronously.

The main goal is to try the k8s stack

• Kubernetes
• Helm

Now settings for subscribers are stored in memory as a Map. It should be stored in persistent NoSQL storage.

Subscribers are grouped by geo position. If two subscribers have different coordinates, one comet will be requested twice. A cache will reduce network traffic

Minor Planet center provides a catalog with data e.g. declination, right accession, etc.
Data is updated once per month (?) and provided as a txt file or json.

I suppose the application can download it periodically and store in a kind of cache.

Links

• https://www.minorplanetcenter.net/data
• https://www.minorplanetcenter.net/iau/MPCORB/CometEls.txt
• https://www.minorplanetcenter.net/Extended_Files/cometels.json.gz

Example of JSON document

{
   "Orbit_type":"C",
   "Provisional_packed_desig":"J95O010",
   "Year_of_perihelion":1997,
   "Month_of_perihelion":3,
   "Day_of_perihelion":29.6731,
   "Perihelion_dist":0.912926,
   "e":0.994933,
   "Peri":130.6132,
   "Node":283.3721,
   "i":88.9848,
   "Epoch_year":2020,
   "Epoch_month":5,
   "Epoch_day":31,
   "H":-2.0,
   "G":4.0,
   "Designation_and_name":"C/1995 O1 (Hale-Bopp)",
   "Ref":"MPC106342"
}

The idea was to save perihelion date in calendar (Google or something different). But for it seems redundant to me, so I am closing this issue

Think about

• Move from Heroku to Google Cloud
• Get rid of Vault

There is a library called Testcontainers. It allows to run docker containers during unit tests. I would like to test how it works with Quarkus.

So we need to implement a couple of integration tests

POST https://www.heavens-above.com/comet.aspx?cid=C%2F2020%20F3&lat=0&lng=0&loc=Unspecified&alt=0&tz=GMT&cul=en

Form Data

utcOffset | "3600000"
-- | --
ctl00$ddlCulture | "ru"
ctl00$cph1$TimeSelectionControl1$comboYear | "2020"
ctl00$cph1$TimeSelectionControl1$comboMonth | "7"
ctl00$cph1$TimeSelectionControl1$comboDay | "9"
ctl00$cph1$TimeSelectionControl1$txtTime | "19:49:29"

When application is started, it tries to retrieve credentials for mail server. However, Vault server cannot be started yet (e. g. with Heroku free plan).

There is no ability to unsubscribe in the application, but only through API.
Email message should include a link that deletes a user from the system. When #7 is done, there will be a dedicated page for that

Heroku does not work well with Couch DB, so let's use Mongo DB instead

Quarkus mailing extension tries to initialize mailer eagerly at startup time. It also requests Vault for credentials. Sometimes it is a problem.

• Set up keystore for application
• Set up policies
• Set up key generation for Mongo
• Deal with unsealing at startup in docker

https://eclipse.gsfc.nasa.gov/solar.html

• Add maven profile that builds fat jar
• Add docker file for building and packaging the application
• Set up an account on Heroku
• Set up a github action that deploys the app on Heroku

• Weather
• Sunset/Sunrise time - https://sunrise-sunset.org/api
• Constellation visibility

Currently if I try to send email message to gmail address from docker container, a error message appears

smtp_1  |   278   SMTP<< 550-5.7.1 [78.85.154.29] The IP you're using to send mail is not authorized to
smtp_1  |   278          550-5.7.1 send email directly to our servers. Please use the SMTP relay at your
smtp_1  |   278          550-5.7.1 service provider instead. Learn more at
smtp_1  |   278          550 5.7.1  https://support.google.com/mail/?p=NotAuthorizedError j21si9015166lfg.108 - gsmtp
smtp_1  |   278   SMTP>> QUIT
smtp_1  |   278   SMTP(close)>>

In this project I want to use Quarkus instead of Spring Boot. For now it would be an application that periodically pull data from Heavens-above and prints it.

A simple CRUD for current subscriptions

• Get all emails subscribed to the service
• Ability to add new email
• Ability to delete email from mailing list

The class should take data from https://www.heavens-above.com/Comets.aspx and return a list of Java objects.