Isolate Hasher behind typed installer adapter

1 files changed, 91 insertions, 0 deletions

diff --git a/src/package_installer.rs b/src/package_installer.rs
new file mode 100644
index 0000000..b08c469
--- /dev/null
+++ b/src/package_installer.rs
@@ -0,0 +1,91 @@
+use std::path::{Path, PathBuf};
+
+use anyhow::{bail, Result};
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct AptConfig(PathBuf);
+
+impl AptConfig {
+    pub fn new(path: impl AsRef<Path>) -> Result<Self> {
+        let path = path.as_ref();
+        if path.as_os_str().is_empty() || path.is_dir() {
+            bail!("APT configuration must be a file path: {}", path.display());
+        }
+        Ok(Self(path.to_path_buf()))
+    }
+
+    pub fn as_path(&self) -> &Path {
+        &self.0
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct PackageRequest {
+    workdir: PathBuf,
+    apt_config: AptConfig,
+    packages: Vec<String>,
+    selectors: Vec<String>,
+}
+
+impl PackageRequest {
+    pub fn new(
+        workdir: impl AsRef<Path>,
+        apt_config: AptConfig,
+        packages: impl IntoIterator<Item = impl Into<String>>,
+        selectors: impl IntoIterator<Item = impl Into<String>>,
+    ) -> Result<Self> {
+        let workdir = workdir.as_ref();
+        if workdir.as_os_str().is_empty() {
+            bail!("Hasher workdir cannot be empty");
+        }
+
+        let mut packages = normalize("package", packages)?;
+        let mut selectors = normalize("package selector", selectors)?;
+        packages.sort();
+        packages.dedup();
+        selectors.sort();
+        selectors.dedup();
+        Ok(Self {
+            workdir: workdir.to_path_buf(),
+            apt_config,
+            packages,
+            selectors,
+        })
+    }
+
+    pub fn workdir(&self) -> &Path {
+        &self.workdir
+    }
+
+    pub fn apt_config(&self) -> &AptConfig {
+        &self.apt_config
+    }
+
+    pub fn packages(&self) -> &[String] {
+        &self.packages
+    }
+
+    pub fn selectors(&self) -> &[String] {
+        &self.selectors
+    }
+}
+
+fn normalize(
+    kind: &str,
+    values: impl IntoIterator<Item = impl Into<String>>,
+) -> Result<Vec<String>> {
+    values
+        .into_iter()
+        .map(Into::into)
+        .map(|value: String| {
+            if value.trim().is_empty() {
+                bail!("{kind} cannot be empty");
+            }
+            Ok(value)
+        })
+        .collect()
+}
+
+pub trait PackageInstaller {
+    fn install(&self, request: &PackageRequest) -> Result<()>;
+}