feat: detect wich operating system the user uses (#6)

feat: create an enum of supported language

feat: detect if the user is on linux

feat: read the `/etc/os-releas` file to get the os

refactor: change `Result` type to have `DepotError` be silenced

test: print the os name

test: add bash script to quickly test on all os

.gitignore

@@ -3,7 +3,6 @@
 debug/
 target/
 
-
 # These are backup files generated by rustfmt
 **/*.rs.bk
 

src/lib.rs

@@ -0,0 +1,62 @@
+use std::io::Read;
+
+/// List of errors that the program can return.
+#[derive(Debug)]
+pub enum DepotError {
+    UnknownOperatingSystem,
+}
+
+/// Result type wich wither take a type T or a DepotError.
+pub type DepotResult<T> = std::result::Result<T, DepotError>;
+pub fn unwrap_depot_error<T>(result: DepotResult<T>) -> T {
+    match result {
+        Ok(value) => value,
+        Err(error) => {
+            eprintln!(
+                "{}",
+                match error {
+                    DepotError::UnknownOperatingSystem =>
+                        "Unable to determine your current operating system.",
+                }
+            );
+            std::process::exit(1);
+        }
+    }
+}
+
+/// List of all supported operating systems.
+#[derive(Debug)]
+pub enum OperatingSystem {
+    Arch,
+    Alpine,
+    Debian,
+    Ubuntu,
+    Fedora,
+}
+impl OperatingSystem {
+    /// Get the currently running operating system.
+    pub fn current() -> DepotResult<OperatingSystem> {
+        match std::env::consts::OS {
+            "linux" => {
+                let mut contents = String::new();
+                std::fs::File::open("/etc/os-release")
+                    .unwrap()
+                    .read_to_string(&mut contents)
+                    .unwrap();
+                match contents
+                    .split('\n')
+                    .find(|line| line.starts_with("ID="))
+                    .unwrap()
+                {
+                    "ID=arch" => Ok(OperatingSystem::Arch),
+                    "ID=alpine" => Ok(OperatingSystem::Alpine),
+                    "ID=debian" => Ok(OperatingSystem::Debian),
+                    "ID=ubuntu" => Ok(OperatingSystem::Ubuntu),
+                    "ID=fedora" => Ok(OperatingSystem::Fedora),
+                    _ => Err(DepotError::UnknownOperatingSystem),
+                }
+            }
+            _ => Err(DepotError::UnknownOperatingSystem),
+        }
+    }
+}

src/main.rs

@@ -1,3 +1,12 @@
+use depot::{unwrap_depot_error, OperatingSystem};
+
+/// Main function of the program
+/// Parse the command line arguments
+/// Look for the package manager in
+///  - the command line arguments
+///  - the environment variables
+///  - get the os name and deduce it from there
 fn main() {
-    println!("Hello, world!");
+    let os = unwrap_depot_error(OperatingSystem::current());
+    println!("OS: {:?}", os);
 }

test/Dockerfiles-os/Dockerfile.alpine

@@ -0,0 +1,7 @@
+# bash says that the binary is not found on alpine
+FROM alpine
+
+WORKDIR /app
+COPY ./target/release/depot ./
+CMD ["./depot"]
+

test/Dockerfiles-os/Dockerfile.arch

@@ -0,0 +1,6 @@
+FROM archlinux/archlinux
+
+WORKDIR /app
+COPY ./target/release/depot ./
+CMD ["./depot"]
+

test/Dockerfiles-os/Dockerfile.debian

@@ -0,0 +1,6 @@
+FROM debian
+
+WORKDIR /app
+COPY ./target/release/depot ./
+CMD ["./depot"]
+

test/Dockerfiles-os/Dockerfile.fedora

@@ -0,0 +1,6 @@
+FROM fedora
+
+WORKDIR /app
+COPY ./target/release/depot ./
+CMD ["./depot"]
+

test/Dockerfiles-os/Dockerfile.ubuntu

@@ -0,0 +1,6 @@
+FROM ubuntu
+
+WORKDIR /app
+COPY ./target/release/depot ./
+CMD ["./depot"]
+

test/test_on_all_os.sh

@@ -0,0 +1,36 @@
+#!/bin/bash
+
+# check if the script is executed from the parent directory of where it is located
+script_dir=$(dirname "$(realpath "$0")")
+if [ "$(dirname "$script_dir")" != "$(pwd)" ]; then
+    echo "Please execute the script from the parent directory of where it is located."
+    exit 1
+fi
+
+# get the list of all Dockerfiles from the Dockerfiles directory
+dockerfiles=$(find "$script_dir/Dockerfiles-os" -type f -name "Dockerfile*")
+
+# get the end of each Dockerfile name (e.g., Dockerfile.ubuntu -> ubuntu)
+os_names=$(echo "$dockerfiles" | sed -n 's/.*Dockerfile\.\(.*\)/\1/p')
+
+# build the rust project
+cargo build --release
+
+# build all Docker images
+for os_name in $os_names; do
+    docker build -t "test_on_all_os:$os_name" -f "$script_dir/Dockerfiles-os/Dockerfile.$os_name" .
+done
+
+echo ""
+
+# run all docker containers and say the OS name
+for os_name in $os_names; do
+    echo "test from: $os_name"
+    docker run --rm "test_on_all_os:$os_name"
+done
+
+echo ""
+
+# remove all Docker images
+docker rmi $(docker images -q test_on_all_os)
+