Panic when no network

I hadn’t seen this before, so I wanted to check and see if it was normal…or figure out how to keep it from happening.

When I don’t have internet I have the following happening:

thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: reqwest::Error { kind: Request, url: Url { scheme: "https", cannot_be_a_base: false, username: "", password: None, host: Some(Domain("")), port: None, path: "/dfinity/vessel-package-set/releases/download/mo-0.8.1-20230203/package-set.dhall", query: None, fragment: None }, source: hyper::Error(Connect, ConnectError("dns error", Custom { kind: Uncategorized, error: "failed to lookup address information: nodename nor servname provided, or not known" })) }', /Users/runner/.cargo/registry/src/
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

The only sort of odd thing I have going on is that in my vessel.dhall I have:
let upstream =

and usually, I have a sha there, but I couldn’t find where to look for it.

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From ChatGPT

It sounds like you’re encountering an error when using the Dhall programming language. The error message you provided indicates that the program is trying to access a file from the internet using a URL (, but it’s unable to connect to the internet and is failing with a “dns error.”

In this specific case, it appears that the file you’re trying to access is located on GitHub, and you’re trying to download it using the URL However, since you don’t have internet access, this URL is not reachable and you’re encountering the error.

Regarding the missing SHA, it’s possible that the file you’re trying to access is usually identified by a specific SHA (a secure hash of its contents), which provides a unique identifier for a specific version of the file. This is a common practice in software development to ensure that you’re using the correct version of a file.

If you need to work with this file without internet access, you might consider downloading the file and storing it locally, and then updating the Dhall program to reference the local file instead of the URL. This should allow you to continue working with the program even when you don’t have internet access.