Move templates and plugins shared data dir methods to common crate

Signed-off-by: Kate Goldenring <kate.goldenring@fermyon.com>

crates/common/Cargo.toml

@@ -6,6 +6,7 @@ edition = { workspace = true }
 
 [dependencies]
 anyhow = "1.0"
+dirs = "4.0"
 sha2 = "0.10"
 tokio = { version = "1", features = ["rt", "time"] }
 

crates/common/src/data_dir.rs

@@ -0,0 +1,29 @@
+//! Resolves Spin's default data directory paths
+
+use anyhow::{anyhow, Result};
+use std::path::{Path, PathBuf};
+
+/// Return the default data directory for Spin
+pub fn default_data_dir() -> Result<PathBuf> {
+    if let Some(pkg_mgr_dir) = package_manager_data_dir() {
+        return Ok(pkg_mgr_dir);
+    }
+
+    let data_dir = dirs::data_local_dir()
+        .or_else(|| dirs::home_dir().map(|p| p.join(".spin")))
+        .ok_or_else(|| anyhow!("Unable to get local data directory or home directory"))?;
+    Ok(data_dir.join("spin"))
+}
+
+/// Get the package manager specific data directory
+fn package_manager_data_dir() -> Option<PathBuf> {
+    if let Ok(brew_prefix) = std::env::var("HOMEBREW_PREFIX") {
+        let data_dir = Path::new(&brew_prefix).join("var").join("spin");
+
+        if data_dir.is_dir() {
+            return Some(data_dir);
+            // TODO: check if they also have plugins in non-brew default dir and warn
+        }
+    }
+    None
+}

crates/common/src/lib.rs

@@ -9,5 +9,6 @@
 // - Code should have at least 2 dependents
 
 pub mod arg_parser;
+pub mod data_dir;
 pub mod sha256;
 pub mod sloth;

crates/plugins/src/store.rs

@@ -1,5 +1,6 @@
-use anyhow::{anyhow, Context, Result};
+use anyhow::{Context, Result};
 use flate2::read::GzDecoder;
+use spin_common::data_dir::default_data_dir;
 use std::{
     ffi::OsStr,
     fs::{self, File},
@@ -24,25 +25,10 @@ impl PluginStore {
     }
 
     pub fn try_default() -> Result<Self> {
-        if let Ok(brew_prefix) = std::env::var("HOMEBREW_PREFIX") {
-            let plugins_dir = Path::new(&brew_prefix)
-                .join("var")
-                .join("spin")
-                .join("plugins");
-
-            if plugins_dir.is_dir() {
-                return Ok(Self::new(plugins_dir));
-                // TODO: check if they also have plugins in non-brew default dir and warn
-            }
+        if let Ok(test_dir) = std::env::var("TEST_PLUGINS_DIRECTORY") {
+            return Ok(Self::new(PathBuf::from(test_dir)));
         }
-        let data_dir = match std::env::var("TEST_PLUGINS_DIRECTORY") {
-            Ok(test_dir) => PathBuf::from(test_dir),
-            Err(_) => dirs::data_local_dir()
-                .or_else(|| dirs::home_dir().map(|p| p.join(".spin")))
-                .ok_or_else(|| anyhow!("Unable to get local data directory or home directory"))?,
-        };
-        let plugins_dir = data_dir.join("spin").join("plugins");
-        Ok(Self::new(plugins_dir))
+        Ok(Self::new(default_data_dir()?.join("plugins")))
     }
 
     /// Gets the path to where Spin plugin are installed.

crates/templates/src/store.rs

@@ -1,7 +1,7 @@
+use anyhow::Context;
+use spin_common::data_dir::default_data_dir;
 use std::path::{Path, PathBuf};
 
-use anyhow::{anyhow, Context};
-
 use crate::directory::subdirectories;
 
 pub(crate) struct TemplateStore {
@@ -20,23 +20,7 @@ impl TemplateStore {
     }
 
     pub(crate) fn try_default() -> anyhow::Result<Self> {
-        if let Ok(brew_prefix) = std::env::var("HOMEBREW_PREFIX") {
-            let templates_dir = Path::new(&brew_prefix)
-                .join("var")
-                .join("spin")
-                .join("templates");
-
-            if templates_dir.is_dir() {
-                return Ok(Self::new(templates_dir));
-                // TODO: check if they also have templates in non-brew default dir and warn
-            }
-        }
-
-        let data_dir = dirs::data_local_dir()
-            .or_else(|| dirs::home_dir().map(|p| p.join(".spin")))
-            .ok_or_else(|| anyhow!("Unable to get local data directory or home directory"))?;
-        let templates_dir = data_dir.join("spin").join("templates");
-        Ok(Self::new(templates_dir))
+        Ok(Self::new(default_data_dir()?.join("templates")))
     }
 
     pub(crate) fn get_directory(&self, id: impl AsRef<str>) -> PathBuf {