How Can I Efficiently Fetch and Display the User's Location-Based Zip Code in an Elixir Application?

Questions / Help
1

I’ve been exploring Elixir and Phoenix for a while now and recently came across a use case where I need to retrieve a user’s zip code based on their GPS location. The concept is somewhat similar to various ‘Find my zip code’ tools, which leverages a device’s GPS to determine and display the zip code of the user’s current location.

Given Elixir’s strengths in handling concurrent processes and its robust ecosystem, I’m curious about the most efficient way to implement this functionality in an Elixir-based application. Here’s what I’m particularly interested in:

  1. Best Approach for Accessing GPS Data: What would be the recommended method for accessing the user’s GPS data in Elixir? Since this involves interacting with the user’s device, I assume that this would require some sort of integration with front-end technologies or libraries. How should I approach this in a Phoenix application, or is there a more straightforward method within Elixir?
  2. Handling Location-Based Data: Once the GPS coordinates are obtained, how should I go about converting these into a zip code? Is there an existing library or API in the Elixir ecosystem that can facilitate this, or would I need to interact with an external API? If external APIs are the way to go, which ones would you recommend that are both reliable and easy to integrate with Elixir?
  3. Displaying the Zip Code Efficiently: After retrieving the zip code, what’s the best practice for displaying it to the user? Are there any built-in tools or libraries within Phoenix or Elixir that can help in rendering this data quickly and efficiently on the front end? Should I be considering real-time updates, and if so, what’s the most efficient way to implement this using Elixir’s strengths?
  4. Security and Privacy Concerns: Given that this feature would involve accessing potentially sensitive information like the user’s location, what are the best practices in Elixir/Phoenix for ensuring this data is handled securely? How should I manage permissions and user consent to avoid any privacy issues?
  5. Handling Edge Cases: Are there any specific challenges or edge cases I should be aware of when working with GPS data and location-based services in Elixir? For instance, how should I handle situations where the user denies access to their location, or where GPS data is inaccurate or unavailable? What are some strategies to ensure the user experience remains smooth even in such cases?
    thanks!
2

Hey there.

I’ve not had to fetch GPS data but I do believe that this would involve GPX files, here is a project in which someone uses GPX and PostGIS (this is a postgres extension for dealing with geospatial data) to build an app that tracks one’s bicycle routes.

It is from 4 years ago, so the elixir used may need one or two tweaks, but the main point of providing that link was to address your “get the location data” objective.

Once you have the ordinances you should be able to generate a list of other ordinances within a 1 mile radius (PostGIS allows track distance measurements). Depending on the country in which you are living, you can get a dataset that contains post/zip codes and their respective ordinances, usually as a csv file.

With the ordinances and the dataset you can determine the person’s zip code, or whether the person is within 1 mile of a zip code.

I have not implemented the objectives you have outlined, however, ordinance and postcode data can be obtained from public datasets, and even the Google Places API (but in the case of google this would be if you already have the zip code, place-name, or ordinance already).

You could then query the local data from the most recent ordinance to check if the person has moved a 100m or so from the last code/ordinance pair, and then send a request to the db for an updated code.

Hope that helps somewhat.

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