Fix custom endpoint, 3rd time's the charm (#117)

Author: martin-helmich

config/structs.go

@@ -69,3 +69,13 @@ func (c *Config) StabilityWarnings() error {
 
 	return nil
 }
+
+// MetricsEndpointOrDefault returns the configured metrics endpoint or the
+// default value if no configuration was provided.
+func (l *ListenConfig) MetricsEndpointOrDefault() string {
+	if l.MetricsEndpoint == "" {
+		return "/metrics"
+	}
+
+	return l.MetricsEndpoint
+}

features/custom_endpoint.feature

@@ -0,0 +1,9 @@
+Feature: Custom endpoint
+
+  Scenario: Custom endpoint can be used
+    Given a running exporter listening with configuration file "test-config-custom-endpoint.yaml"
+    When the following HTTP request is logged to "access.log"
+      """
+      172.17.0.1 - - [23/Jun/2016:16:04:20 +0000] "GET / HTTP/1.1" 200 612 "-" "curl/7.29.0" "-"
+      """
+    Then the exporter should on "/custom" report value 1 for metric nginx_http_response_count_total{method="GET",status="200"}

features/steps/steps.py

@@ -72,15 +72,20 @@ def step_impl(context, port):
 
 
 @then(u'the exporter should report value {val} for metric {metric}')
-def step_impl(context, val, metric):
+@then(u'the exporter should on "{endpoint}" report value {val} for metric {metric}')
+def step_impl(context, val, metric, endpoint = '/metrics'):
+    endpoint = endpoint.lstrip("/")
     while True:
         try:
-            response = requests.get('http://localhost:4040/metrics')
+            url = 'http://localhost:4040/%s' % endpoint
+            print(url)
+            response = requests.get(url)
             text = response.text
             break
         except requests.ConnectionError:
             continue
 
     lines = [l.strip("\n") for l in text.split("\n")]
     if not "%s %s" % (metric, val) in lines:
-        raise AssertionError('expected metric "%s" could not be verified. Actual metrics:\n%s' % (context.text, text))
+        raise AssertionError('expected metric "%s" could not be verified. Actual metrics:\n%s' % (metric, text))
+

features/test-config-custom-endpoint.yaml

@@ -0,0 +1,11 @@
+listen:
+  port: 4040
+  metrics_endpoint: /custom
+
+namespaces:
+  - name: nginx
+    source:
+      files:
+        - .behave-sandbox/access.log
+    format: "$remote_addr - $remote_user [$time_local] \"$request\" $status $body_bytes_sent \"$http_referer\" \"$http_user_agent\" \"$http_x_forwarded_for\""
+    histogram_buckets: [.005, .01, .025, .05, .1, .25, .5, 1, 2.5, 5, 10]

go.mod

@@ -16,8 +16,6 @@ require (
 	github.com/konsorten/go-windows-terminal-sequences v1.0.2 // indirect
 	github.com/kr/pretty v0.2.0 // indirect
 	github.com/kr/pty v1.1.8 // indirect
-	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
-	github.com/modern-go/reflect2 v1.0.1 // indirect
 	github.com/mwitkow/go-conntrack v0.0.0-20190716064945-2f068394615f // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/prometheus/client_golang v1.6.0

go.sum

@@ -37,6 +37,7 @@ github.com/golang/protobuf v1.4.0-rc.1/go.mod h1:ceaxUfeHdC40wWswd/P6IGgMaK3YpKi
 github.com/golang/protobuf v1.4.0-rc.1.0.20200221234624-67d41d38c208/go.mod h1:xKAWHe0F5eneWXFV3EuXVDTCmh+JuBKY0li0aMyXATA=
 github.com/golang/protobuf v1.4.0-rc.2/go.mod h1:LlEzMj4AhA7rCAGe4KMBDvJI+AwstrUpVNzEA03Pprs=
 github.com/golang/protobuf v1.4.0-rc.4.0.20200313231945-b860323f09d0/go.mod h1:WU3c8KckQ9AFe+yFwt9sWVRKCVIyN9cPHBJSNnbL67w=
+github.com/golang/protobuf v1.4.0 h1:oOuy+ugB+P/kBdUnG5QaMXSIyJ1q38wWSojYCb3z5VQ=
 github.com/golang/protobuf v1.4.0/go.mod h1:jodUvKwWbYaEsadDk5Fwe5c77LiNKVO9IDvqG2KuDX0=
 github.com/google/go-cmp v0.3.0/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
 github.com/google/go-cmp v0.3.1/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
@@ -105,6 +106,7 @@ github.com/prometheus/procfs v0.0.0-20181005140218-185b4288413d/go.mod h1:c3At6R
 github.com/prometheus/procfs v0.0.2/go.mod h1:TjEm7ze935MbeOT/UhFTIMYKhuLP4wbCsTZCD3I8kEA=
 github.com/prometheus/procfs v0.0.8 h1:+fpWZdT24pJBiqJdAwYBjPSk+5YmQzYNPYzQsdzLkt8=
 github.com/prometheus/procfs v0.0.8/go.mod h1:7Qr8sr6344vo1JqZ6HhLceV9o3AJ1Ff+GxbHq6oeK9A=
+github.com/prometheus/procfs v0.0.11 h1:DhHlBtkHWPYi8O2y31JkK0TF+DGM+51OopZjH/Ia5qI=
 github.com/prometheus/procfs v0.0.11/go.mod h1:lV6e/gmhEcM9IjHGsFOCxxuZ+z1YqCvr4OA4YeYWdaU=
 github.com/satyrius/gonx v1.3.1-0.20180709120835-47c52b995fe5 h1:nIAK+9DnhpSebWeiIqvPr0rqSDC3j9r1I2bp0OJAYVE=
 github.com/satyrius/gonx v1.3.1-0.20180709120835-47c52b995fe5/go.mod h1:+r8KNe5d2tjkZU+DfhERo0G6KxkGih+1qYF6tqLHwvk=
@@ -151,6 +153,7 @@ golang.org/x/sys v0.0.0-20200106162015-b016eb3dc98e/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20200122134326-e047566fdf82/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200202164722-d101bd2416d5 h1:LfCXLvNmTYH9kEmVgqbnsWfruoXZIrh4YBgqVHtDvw0=
 golang.org/x/sys v0.0.0-20200202164722-d101bd2416d5/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20200420163511-1957bb5e6d1f h1:gWF768j/LaZugp8dyS4UwsslYCYz9XgFxvlgsn0n9H8=
 golang.org/x/sys v0.0.0-20200420163511-1957bb5e6d1f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
@@ -165,6 +168,7 @@ google.golang.org/protobuf v0.0.0-20200109180630-ec00e32a8dfd/go.mod h1:DFci5gLY
 google.golang.org/protobuf v0.0.0-20200221191635-4d8936d0db64/go.mod h1:kwYJMbMJ01Woi6D6+Kah6886xMZcty6N08ah7+eCXa0=
 google.golang.org/protobuf v0.0.0-20200228230310-ab0ca4ff8a60/go.mod h1:cfTl7dwQJ+fmap5saPgwCLgHXTUD7jkjRqWcaiX5VyM=
 google.golang.org/protobuf v1.20.1-0.20200309200217-e05f789c0967/go.mod h1:A+miEFZTKqfCUM6K7xSMQL9OKL/b6hQv+e19PK+JZNE=
+google.golang.org/protobuf v1.21.0 h1:qdOKuR/EIArgaWNjetjgTzgVTAZ+S/WXVrq9HW9zimw=
 google.golang.org/protobuf v1.21.0/go.mod h1:47Nbq4nVaFHyn7ilMalzfO3qCViNmqZ2kzikPIcrTAo=
 gopkg.in/alecthomas/kingpin.v2 v2.2.6/go.mod h1:FMv+mEhP44yOT+4EoQTLFTRgOQ1FBLkstjWtayDeSgw=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=

main.go

@@ -199,9 +199,11 @@ func main() {
 	}
 
 	listenAddr := fmt.Sprintf("%s:%d", cfg.Listen.Address, cfg.Listen.Port)
-	fmt.Printf("running HTTP server on address %s\n", listenAddr)
+	endpoint := cfg.Listen.MetricsEndpointOrDefault()
 
-	http.Handle(opts.MetricsEndpoint, promhttp.Handler())
+	fmt.Printf("running HTTP server on address %s, serving metrics at %s\n", listenAddr, endpoint)
+
+	http.Handle(endpoint, promhttp.Handler())
 
 	if err := http.ListenAndServe(listenAddr, nil); err != nil {
 		fmt.Printf("error while starting HTTP server: %s", err.Error())