Add support for body_path in HTTP probe config.

config/config.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 	"fmt"
 	"io/ioutil"
+	"os"
 	"runtime"
 	"sync"
 	"time"
@@ -52,19 +53,21 @@ type Module struct {
 
 type HTTPProbe struct {
 	// Defaults to 2xx.
-	ValidStatusCodes       []int                   `yaml:"valid_status_codes,omitempty"`
-	ValidHTTPVersions      []string                `yaml:"valid_http_versions,omitempty"`
-	IPProtocol             string                  `yaml:"preferred_ip_protocol,omitempty"`
-	IPProtocolFallback     bool                    `yaml:"ip_protocol_fallback,omitempty"`
-	NoFollowRedirects      bool                    `yaml:"no_follow_redirects,omitempty"`
-	FailIfSSL              bool                    `yaml:"fail_if_ssl,omitempty"`
-	FailIfNotSSL           bool                    `yaml:"fail_if_not_ssl,omitempty"`
-	Method                 string                  `yaml:"method,omitempty"`
-	Headers                map[string]string       `yaml:"headers,omitempty"`
-	FailIfMatchesRegexp    []string                `yaml:"fail_if_matches_regexp,omitempty"`
-	FailIfNotMatchesRegexp []string                `yaml:"fail_if_not_matches_regexp,omitempty"`
-	Body                   string                  `yaml:"body,omitempty"`
-	HTTPClientConfig       config.HTTPClientConfig `yaml:"http_client_config,inline"`
+	ValidStatusCodes       []int             `yaml:"valid_status_codes,omitempty"`
+	ValidHTTPVersions      []string          `yaml:"valid_http_versions,omitempty"`
+	IPProtocol             string            `yaml:"preferred_ip_protocol,omitempty"`
+	IPProtocolFallback     bool              `yaml:"ip_protocol_fallback,omitempty"`
+	NoFollowRedirects      bool              `yaml:"no_follow_redirects,omitempty"`
+	FailIfSSL              bool              `yaml:"fail_if_ssl,omitempty"`
+	FailIfNotSSL           bool              `yaml:"fail_if_not_ssl,omitempty"`
+	Method                 string            `yaml:"method,omitempty"`
+	Headers                map[string]string `yaml:"headers,omitempty"`
+	FailIfMatchesRegexp    []string          `yaml:"fail_if_matches_regexp,omitempty"`
+	FailIfNotMatchesRegexp []string          `yaml:"fail_if_not_matches_regexp,omitempty"`
+	Body                   string            `yaml:"body,omitempty"`
+	BodyFile               string            `yaml:"body_file,omitempty"`
+
+	HTTPClientConfig config.HTTPClientConfig `yaml:"http_client_config,inline"`
 }
 
 type QueryResponse struct {
@@ -135,6 +138,16 @@ func (s *HTTPProbe) UnmarshalYAML(unmarshal func(interface{}) error) error {
 	if err := s.HTTPClientConfig.Validate(); err != nil {
 		return err
 	}
+	if len(s.Body) > 0 && len(s.BodyFile) > 0 {
+		return errors.New("at most one of body & body_file may be configured")
+	}
+	if s.BodyFile != "" {
+		file, err := os.Open(s.BodyFile)
+		if err != nil {
+			return err
+		}
+		defer file.Close()
+	}
 	return nil
 }
 

prober/http.go

@@ -24,6 +24,7 @@ import (
 	"net/http/cookiejar"
 	"net/http/httptrace"
 	"net/url"
+	"os"
 	"regexp"
 	"strconv"
 	"strings"
@@ -257,10 +258,20 @@ func ProbeHTTP(ctx context.Context, target string, module config.Module, registr
 
 	var body io.Reader
 
-	// If a body is configured, add it to the request.
+	// If a body string is configured, add it to the request.
 	if httpConfig.Body != "" {
 		body = strings.NewReader(httpConfig.Body)
 	}
+	// If a body path is configured, add it to the request.
+	if httpConfig.BodyFile != "" {
+		file, err := os.Open(httpConfig.BodyFile)
+		if err != nil {
+			level.Error(logger).Log("msg", "Error opening body file", "err", err)
+			return
+		}
+		defer file.Close()
+		body = file
+	}
 
 	request, err := http.NewRequest(httpConfig.Method, targetURL.String(), body)
 	request.Host = origHost

prober/http_test.go

@@ -164,6 +164,33 @@ func TestPost(t *testing.T) {
 	}
 }
 
+func TestPostBody(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != "POST" {
+			w.WriteHeader(http.StatusBadRequest)
+		}
+	}))
+	defer ts.Close()
+
+	recorder := httptest.NewRecorder()
+	registry := prometheus.NewRegistry()
+	testCTX, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+	result := ProbeHTTP(testCTX, ts.URL,
+		config.Module{
+			Timeout: time.Second,
+			HTTP: config.HTTPProbe{
+				IPProtocolFallback: true,
+				Method:             "POST",
+				BodyFile:           "./http.go",
+			},
+		}, registry, log.NewNopLogger())
+	body := recorder.Body.String()
+	if !result {
+		t.Fatalf("Post test failed unexpectedly, got %s", body)
+	}
+}
+
 func TestBasicAuth(t *testing.T) {
 	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 	}))