added check for metrics' name suffix similar to the one found in prom…

…etheus-metrics-core (#340)

build.sbt

@@ -34,7 +34,7 @@ lazy val site = project.in(file("site"))
   .dependsOn(core)
 
 
-val prometheusV = "1.1.0"
+val prometheusV = "1.2.1"
 val catsV = "2.9.0"
 val catsEffectV = "3.4.8"
 val shapelessV = "2.3.9"

core/src/main/scala/io/chrisdavenport/epimetheus/NameCommons.scala

@@ -21,8 +21,26 @@ trait NameCommons {
 
   private val reg = "([a-zA-Z_:][a-zA-Z0-9_:]*)".r
 
+  private val forbiddenSuffixes = List(
+    "_total",
+    "_created",
+    "_bucket",
+    "_info",
+    ".total",
+    ".created",
+    ".bucket",
+    ".info"
+  )
+
   def impl(s: String): Either[IllegalArgumentException, Name] = s match {
-    case reg(string) => Either.right(new Name(string))
+    case reg(string) =>
+      if (forbiddenSuffixes.exists(string.endsWith))
+        Left[IllegalArgumentException, Name](
+          new IllegalArgumentException(
+            s"Input String - $s end with one of the forbidden suffixes(${forbiddenSuffixes.mkString(",")})"
+          )
+        )
+      else Either.right(new Name(string))
     case _ => Either.left(
       new IllegalArgumentException(
         s"Input String - $s does not match regex - ([a-zA-Z_:][a-zA-Z0-9_:]*)"

core/src/test/scala/io/chrisdavenport/epimetheus/NameSpec.scala

@@ -22,5 +22,14 @@ class NameSpec extends munit.CatsEffectSuite {
     val goodSuffix = Name.Suffix("0asdfa")
     val errors3 = compileErrors("""Name.Suffix("^")""")
     assert(errors3.nonEmpty)
+
+    assert(compileErrors("""Name("metric_total")""").nonEmpty)
+    assert(compileErrors("""Name("metric_created")""").nonEmpty)
+    assert(compileErrors("""Name("metric_bucket")""").nonEmpty)
+    assert(compileErrors("""Name("metric_info")""").nonEmpty)
+    assert(compileErrors("""Name("metric.total")""").nonEmpty)
+    assert(compileErrors("""Name("metric.created")""").nonEmpty)
+    assert(compileErrors("""Name("metric.bucket")""").nonEmpty)
+    assert(compileErrors("""Name("metric.info")""").nonEmpty)
   }
 }

docs/docs/05-Counter.md

@@ -4,7 +4,7 @@ Counter metric, to track counts, running totals, or events.
 
 If your use case can go up or down consider using a `Gauge` instead.
 Use the `rate()` function in Prometheus to calculate the rate of increase of a Counter.
-By convention, the names of Counters are suffixed by `_total`.
+By convention, the names of Counters are suffixed by `_total`. This suffix is added to metric's name by underlying prometheus-metrics library, do not add it yourself.
 
 A `Counter` is a cumulative metric that represents a single monotonically increasing counter whose value can only increase or be reset to zero on restart. For example, you can use a counter to represent the number of requests served, tasks completed, or errors.
 
@@ -27,12 +27,12 @@ val noLabelsExample = {
     pr <- PrometheusRegistry.build[IO]
     successCounter <- Counter.noLabels(
       pr,
-      Name("example_success_total"),
+      Name("example_success"),
       "Example Counter of Success"
     )
     failureCounter <- Counter.noLabels(
       pr,
-      Name("example_failure_total"),
+      Name("example_failure"),
       "Example Counter of Failure"
     )
     _ <- IO(println("Action Here")).guaranteeCase{
@@ -54,7 +54,7 @@ val labelledExample = {
     pr <- PrometheusRegistry.build[IO]
     counter <- Counter.labelled(
       pr,
-      Name("example_total"),
+      Name("example"),
       "Example Counter",
       Sized(Label("foo")),
       {s: String => Sized(s)}
@@ -95,7 +95,7 @@ val fooAgebraExample = {
     pr <- PrometheusRegistry.build[IO]
     counter <- Counter.labelled(
       pr,
-      Name("example_total"),
+      Name("example"),
       "Example Counter",
       Sized(Label("foo")),
       fooLabel

docs/index.md

@@ -36,7 +36,7 @@ import cats.effect.unsafe.implicits.global
 val noLabelsCounterExample = {
   for {
     pr <- PrometheusRegistry.build[IO]
-    counter <- Counter.noLabels(pr, Name("counter_total"), "Example Counter")
+    counter <- Counter.noLabels(pr, Name("counter"), "Example Counter")
     _ <- counter.inc
     currentMetrics <- pr.write004
   } yield currentMetrics

project/build.properties

@@ -1 +1 @@
-sbt.version=1.6.2
+sbt.version=1.9.9