1 files changed, 70 insertions, 0 deletions
diff --git a/src/metric.rs b/src/metric.rs
new file mode 100644
index 0000000..97c649a
--- /dev/null
+++ b/src/metric.rs
@@ -0,0 +1,70 @@
+use std::fmt::Debug;
+use std::fmt::Display;
+use std::convert::TryInto;
+
+use anyhow::Result;
+use anyhow::Error;
+use num_traits::Num;
+use prometheus_exporter_base::prelude::*;
+
+pub trait IntoNumMetric {
+    type Output: Num + Display + Debug;
+
+    fn into_num_metric(self) -> Self::Output;
+}
+
+impl IntoNumMetric for std::time::Duration {
+    type Output = u64;
+    fn into_num_metric(self) -> Self::Output {
+        self.as_secs()
+    }
+}
+
+impl IntoNumMetric for u8 {
+    type Output = u8;
+    fn into_num_metric(self) -> Self::Output {
+        self
+    }
+}
+
+impl IntoNumMetric for u32 {
+    type Output = u32;
+    fn into_num_metric(self) -> Self::Output {
+        self
+    }
+}
+
+impl IntoNumMetric for i32 {
+    type Output = i32;
+    fn into_num_metric(self) -> Self::Output {
+        self
+    }
+}
+
+
+pub struct Metric<'a, T: IntoNumMetric> {
+    name: &'static str,
+    value: T,
+    description: &'static str,
+    instance: &'a str,
+}
+
+impl<'a, T: IntoNumMetric + Debug> Metric<'a, T> {
+    pub fn new(name: &'static str, value: T, description: &'static str, instance: &'a str) -> Self {
+        log::trace!("New metric: {} = {:?}", name, value);
+        Metric { name, value, description, instance }
+    }
+
+    pub fn into_metric<'b>(self) -> Result<PrometheusMetric<'b>> {
+        let instance = PrometheusInstance::new()
+            .with_label("instance", self.instance)
+            .with_value(self.value.into_num_metric())
+            .with_current_timestamp()
+            .map_err(Error::from)?;
+
+        let mut m = PrometheusMetric::new(self.name, MetricType::Counter, self.description);
+        m.render_and_append_instance(&instance);
+        Ok(m)
+    }
+}
+