prometheus-wai 0.0.0.1 → 0.1.0.0

raw patch · 3 files changed

+46/−28 lines, 3 filesPVP ok

version bump matches the API change (PVP)

API changes (from Hackage documentation)

Files

• CHANGELOG.md +7/−0
• prometheus-wai.cabal +1/−3
• src/System/Metrics/Prometheus/Wai/Middleware.hs +38/−25

@@ -1,5 +1,12 @@ # Changelog +## [0.1.0.0] - 2025-07-14++### Changed++* Changed the metricsEndpointMiddleware API to support more bells and whistles+  without breaking the API in the future.+ ## [0.0.0.1] - 2025-07-14  ### Added

@@ -5,7 +5,7 @@ -- see: https://github.com/sol/hpack  name:           prometheus-wai-version:        0.0.0.1+version:        0.1.0.0 description:    Prometheus metrics for WAI applications homepage:       https://github.com/NorfairKing/prometheus-wai#readme bug-reports:    https://github.com/NorfairKing/prometheus-wai/issues@@ -28,8 +28,6 @@       Paths_prometheus_wai   hs-source-dirs:       src-  build-tool-depends:-      autoexporter:autoexporter   build-depends:       base >=4.7 && <5     , bytestring

@@ -6,9 +6,10 @@   ( registerWaiMetrics,     WaiMetrics (..),     instrumentWaiMiddleware,+    combineRegistrySample,+    MetricsEndpoint (..),+    defaultMetricsEndpoint,     metricsEndpointMiddleware,-    metricsEndpointAtMiddleware,-    metricsEndpointAtMiddlewareWithHook,   ) where @@ -32,6 +33,7 @@ import qualified System.Metrics.Prometheus.Metric.Histogram as Prometheus (Histogram) import qualified System.Metrics.Prometheus.MetricId as Labels import qualified System.Metrics.Prometheus.MetricId as Prometheus (Labels (..))+import qualified System.Metrics.Prometheus.Registry as Prometheus (RegistrySample (..))  data WaiMetrics = WaiMetrics   { waiMetricsStatusCode :: !(Map Int Prometheus.Counter),@@ -64,9 +66,9 @@   let durationBounds =         concat           [ [1, 2, 3, 5],-            [10, 20, 30, 40, 50],-            [100, 200, 300, 400, 500],-            [1_000, 2_000, 3_000, 4_000, 5_000],+            [10, 20 .. 100],+            [100, 200 .. 900],+            [1_000, 2_000 .. 9_000],             [10_000]           ]   waiMetricsDuration <- Prometheus.registerHistogram "http_request_duration_milliseconds" labels durationBounds registry@@ -101,31 +103,42 @@             sendResponse response         else application request sendResponse --- | Add a metrics endpoint using the given registry.-metricsEndpointMiddleware :: Registry -> Wai.Middleware-metricsEndpointMiddleware = metricsEndpointAtMiddleware "/metrics"+combineRegistrySample :: Prometheus.RegistrySample -> Prometheus.RegistrySample -> Prometheus.RegistrySample+combineRegistrySample (Prometheus.RegistrySample a) (Prometheus.RegistrySample b) =+  Prometheus.RegistrySample (M.union a b) --- | Add a metrics endpoint at a given path using the given registry.-metricsEndpointAtMiddleware :: ByteString -> Registry -> Wai.Middleware-metricsEndpointAtMiddleware =-  metricsEndpointAtMiddlewareWithHook (pure ())+data MetricsEndpoint = MetricsEndpoint+  { -- | Path to serve metrics on, e.g. @"/metrics"@+    metricsEndpointPath :: ByteString,+    -- | Registry to sample from+    metricsEndpointRegistry :: Registry,+    -- | Extra samples to be collected 'at the last second', to be combined+    -- with the main registry samples+    metricsEndpointLastSecond :: Maybe (IO Prometheus.RegistrySample)+  } --- | Add a metrics endpoint at a given path and last-minute hook using the given registry.------ This lets you set metrics that are evaluated when the /metrics endpoint is hit.-metricsEndpointAtMiddlewareWithHook ::-  IO () ->-  ByteString ->-  Registry ->-  Wai.Middleware-metricsEndpointAtMiddlewareWithHook lastMinuteHook path registry application request sendResponse =-  if Request.rawPathInfo request == path+defaultMetricsEndpoint :: Registry -> MetricsEndpoint+defaultMetricsEndpoint registry =+  MetricsEndpoint+    { metricsEndpointPath = "/metrics",+      metricsEndpointRegistry = registry,+      metricsEndpointLastSecond = Nothing+    }++metricsEndpointMiddleware :: MetricsEndpoint -> Wai.Middleware+metricsEndpointMiddleware MetricsEndpoint {..} application request sendResponse =+  if Request.rawPathInfo request == metricsEndpointPath     then do-      lastMinuteHook-      s <- Registry.sample registry+      let sampleRegistry = Registry.sample metricsEndpointRegistry+      finalSamples <- case metricsEndpointLastSecond of+        Nothing -> sampleRegistry+        Just lastSecondSample ->+          combineRegistrySample+            <$> sampleRegistry+            <*> lastSecondSample       sendResponse         $ Wai.responseBuilder           HTTP.ok200           [(HTTP.hContentType, "text/plain; version=0.0.4; charset=utf-8")]-        $ Prometheus.encodeMetrics s+        $ Prometheus.encodeMetrics finalSamples     else application request sendResponse