Attempt to implement and test setting static ips from instance metadata

rust/lib/common/src/yaml.rs

@@ -8,3 +8,53 @@ pub fn string(str: &str) -> String {
 pub fn to_string<T: ?Sized + Serialize>(value: &T) -> anyhow::Result<String> {
     serde_yml::to_string(value).context("Could not serialize to yaml")
 }
+
+pub fn from_str<D: for<'de> serde::Deserialize<'de>>(s: &str) -> anyhow::Result<D> {
+    serde_yml::from_str(s).map_err(|e| anyhow::format_err!("{e}:\n{}", extract_context(&e, s)))
+}
+
+fn extract_context(serde_error: &serde_yml::Error, s: &str) -> String {
+    let Some(location) = serde_error.location() else {
+        return String::from("Error provided no location information, could not extract context");
+    };
+    let lines: Vec<_> = s.lines().collect();
+    if lines.len() == 1 {
+        let (col_begin, highlight) = if location.column() > 30 {
+            (location.column() - 30, 30)
+        } else {
+            (1, location.column())
+        };
+        let col_end = if lines[0].len() + 31 < location.column() {
+            lines[0].len() + 1
+        } else {
+            location.column() + 30
+        };
+        let mut line: String = lines[0]
+            .chars()
+            .skip(col_begin - 1)
+            .take(col_end - col_begin)
+            .collect();
+        line.push('\n');
+        line.extend(std::iter::repeat_n(' ', highlight - 1));
+        line.push('^');
+        line
+    } else {
+        let error_line = location.line();
+        let mut result = String::new();
+        if error_line > 1 {
+            result.push_str(&format!("{}: {}\n", error_line - 1, lines[error_line - 2]));
+        }
+        result.push_str(&format!("{}: {}\n", error_line, lines[error_line - 1]));
+        result.push_str(&format!(
+            "{}  {}\n",
+            " ".repeat(error_line.to_string().len()),
+            std::iter::repeat_n(' ', location.column() - 1)
+                .chain(['^'].into_iter())
+                .collect::<String>(),
+        ));
+        if lines.len() > error_line {
+            result.push_str(&format!("{}: {}\n", error_line + 1, lines[error_line]));
+        }
+        result
+    }
+}