Adding upstream version 1.34.4.

Signed-off-by: Daniel Baumann <daniel@debian.org>

plugins/outputs/prometheus_client/prometheus_client_test.go

@@ -0,0 +1,123 @@
+package prometheus_client
+
+import (
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/influxdata/telegraf/testutil"
+)
+
+func TestLandingPage(t *testing.T) {
+	output := PrometheusClient{
+		Listen:            ":0",
+		CollectorsExclude: []string{"process"},
+		MetricVersion:     1,
+		Log:               &testutil.Logger{Name: "outputs.prometheus_client"},
+	}
+	expected := "Telegraf Output Plugin: Prometheus Client"
+
+	require.NoError(t, output.Init())
+	require.NoError(t, output.Connect())
+
+	u, err := url.Parse(fmt.Sprintf("http://%s/", output.url.Host))
+	require.NoError(t, err)
+
+	resp, err := http.Get(u.String())
+	require.NoError(t, err)
+	defer resp.Body.Close()
+
+	actual, err := io.ReadAll(resp.Body)
+	require.NoError(t, err)
+	require.Equal(t, expected, strings.TrimSpace(string(actual)))
+}
+
+func TestFormatHeader(t *testing.T) {
+	tests := []struct {
+		name     string
+		accept   string
+		expected string
+	}{
+		{
+			name:     "invalid accept ",
+			accept:   "applications/json",
+			expected: "text/plain; version=0.0.4; charset=utf-8; escaping=underscores",
+		},
+		{
+			name:     "no accept header",
+			expected: "text/plain; version=0.0.4; charset=utf-8; escaping=underscores",
+		},
+		{
+			name:     "text no version",
+			accept:   "text/plain",
+			expected: "text/plain; version=0.0.4; charset=utf-8; escaping=underscores",
+		},
+		{
+			name:     "text with version 0.0.4",
+			accept:   "text/plain; version=0.0.4",
+			expected: "text/plain; version=0.0.4; charset=utf-8; escaping=underscores",
+		},
+		{
+			name:     "protobuf text format",
+			accept:   "application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=text",
+			expected: "application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=text; escaping=underscores",
+		},
+		{
+			name:     "protobuf compact text format",
+			accept:   "application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=compact-text",
+			expected: "application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=compact-text; escaping=underscores",
+		},
+		{
+			name:     "protobuf delimited format",
+			accept:   "application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=delimited",
+			expected: "application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=delimited; escaping=underscores",
+		},
+		{
+			name:     "multiple accept preferring protobuf",
+			accept:   "application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=delimited, text/plain",
+			expected: "application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=delimited; escaping=underscores",
+		},
+		{
+			name:     "multiple accept preferring text",
+			accept:   "text/plain, application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=delimited",
+			expected: "text/plain; version=0.0.4; charset=utf-8; escaping=underscores",
+		},
+	}
+
+	// Setup the plugin
+	plugin := PrometheusClient{
+		Listen: ":0",
+		Log:    testutil.Logger{Name: "outputs.prometheus_client"},
+	}
+	require.NoError(t, plugin.Init())
+	require.NoError(t, plugin.Connect())
+
+	// Get the plugin's address so we can send data to it
+	addr := fmt.Sprintf("http://%s/metrics", plugin.url.Host)
+
+	// Run the actual tests
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			// Construct a request with the given "Accept" header
+			req, err := http.NewRequest("GET", addr, nil)
+			require.NoError(t, err)
+			if tt.accept != "" {
+				req.Header.Add("Accept", tt.accept)
+			}
+
+			// Get the metrics
+			resp, err := http.DefaultClient.Do(req)
+			require.NoError(t, err)
+			defer resp.Body.Close()
+
+			// Test the result
+			require.NotEmpty(t, resp.Body)
+			require.Equal(t, tt.expected, resp.Header.Get("Content-Type"))
+		})
+	}
+}