From 02adc7dcd216eefba9245d69d187de2d4d153630 Mon Sep 17 00:00:00 2001
From: Paul Campbell <pcampbell@kemitix.net>
Date: Sat, 9 Nov 2024 07:52:42 +0000
Subject: [PATCH] docs(example): get and save

---
 Cargo.toml      |  9 ++++--
 examples/get.rs | 82 +++++++++++++++++++++++++++++++++++++++++++++++++
 justfile        |  1 +
 3 files changed, 89 insertions(+), 3 deletions(-)
 create mode 100644 examples/get.rs

diff --git a/Cargo.toml b/Cargo.toml
index 7b2c872..80ab5fc 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -15,9 +15,9 @@ unexpected_cfgs = { level = "warn", check-cfg = ['cfg(tarpaulin_include)'] }
 
 [dependencies]
 derive_more = { version = "1.0", features = [ 
-  "from", 
+  "constructor",
   "display", 
-  "constructor" 
+  "from" 
 ] }
 http = "1.1"
 path-clean = "1.0"
@@ -28,7 +28,10 @@ tempfile = "3.10"
 assert2 = "0.3"
 pretty_assertions = "1.4"
 test-log = "0.2"
-tokio = { version = "1.41", features = ["macros"] }
+tokio = { version = "1.41", features = [
+  "macros",
+  "rt-multi-thread"
+] }
 tokio-test = "0.4"
 
 [package.metadata.bin]
diff --git a/examples/get.rs b/examples/get.rs
new file mode 100644
index 0000000..0186b8a
--- /dev/null
+++ b/examples/get.rs
@@ -0,0 +1,82 @@
+// example to show fetching a URL and saving to a file
+
+use std::path::Path;
+
+#[tokio::main]
+async fn main() -> kxio::Result<()> {
+    let net = kxio::net::new();
+    let fs = kxio::fs::temp()?;
+
+    let url = "https://git.kemitix.net/kemitix/kxio/raw/branch/main/README.md";
+    let file_path = fs.base().join("README.md");
+
+    download_and_save(url, &file_path, &fs, &net).await?;
+
+    print_file(&file_path, &fs)?;
+
+    Ok(())
+}
+
+async fn download_and_save(
+    url: &str,
+    file_path: &Path,
+    fs: &kxio::fs::FileSystem,
+    net: &kxio::net::Net,
+) -> kxio::Result<()> {
+    println!("fetching: {url}");
+    let request = net.client().get(url);
+    let response = net.send(request).await?;
+    let body = response.text().await?;
+    println!("fetched {} bytes", body.bytes().len());
+
+    println!("writing file: {}", file_path.display());
+    let file = fs.file(file_path);
+    file.write(body)?;
+
+    Ok(())
+}
+
+fn print_file(file_path: &Path, fs: &kxio::fs::FileSystem) -> kxio::Result<()> {
+    println!("reading file: {}", file_path.display());
+    let file = fs.file(file_path);
+    let reader = file.reader()?;
+    let contents = reader.as_str();
+    println!("{contents}");
+
+    Ok(())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[tokio::test]
+    async fn should_save_remote_body() {
+        //given
+        let net = kxio::net::mock();
+        let url = "http://localhost:8080";
+        net.on(net.client().get(url).build().expect("request"))
+            .respond(
+                net.response()
+                    .body("contents")
+                    .expect("response body")
+                    .into(),
+            )
+            .expect("mock");
+
+        let fs = kxio::fs::temp().expect("temp fs");
+        let file_path = fs.base().join("foo");
+
+        //when
+        download_and_save(url, &file_path, &fs, &net.into())
+            .await
+            .expect("system under test");
+
+        //then
+        let file = fs.file(&file_path);
+        let reader = file.reader().expect("reader");
+        let contents = reader.as_str();
+
+        assert_eq!(contents, "contents");
+    }
+}
diff --git a/justfile b/justfile
index 235afc2..c1ee93f 100644
--- a/justfile
+++ b/justfile
@@ -7,6 +7,7 @@ build:
   cargo hack build
   cargo hack test
   cargo doc
+  cargo test --example get
 
 install-hooks:
   @echo "Installing git hooks"