Merge pull request #164 from ivanpesin/static-parameter-warning

Static parameter warning

README.md

@@ -35,8 +35,8 @@ $ go get github.com/adnanh/webhook
 to get the latest version of the [webhook](https://github.com/adnanh/webhook/).
 
 ### Using package manager
-#### Debian "sid"
-If you are using unstable version of Debian linux ("sid"), you can install webhook using `apt-get install webhook` which will install community packaged version (thanks [@freeekanayaka](https://github.com/freeekanayaka)) from https://packages.debian.org/sid/webhook
+#### Debian
+If you are using Debian linux ("stretch" or later), you can install webhook using `apt-get install webhook` which will install community packaged version (thanks [@freeekanayaka](https://github.com/freeekanayaka)) from https://packages.debian.org/sid/webhook
 
 ### Download prebuilt binaries
 Prebuilt binaries for different architectures are available at [GitHub Releases](https://github.com/adnanh/webhook/releases).

webhook.go

@@ -318,7 +318,21 @@ func hookHandler(w http.ResponseWriter, r *http.Request) {
 func handleHook(h *hook.Hook, rid string, headers, query, payload *map[string]interface{}, body *[]byte) (string, error) {
 	var errors []error
 
-	cmd := exec.Command(h.ExecuteCommand)
+	// check the command exists
+	cmdPath, err := exec.LookPath(h.ExecuteCommand)
+	if err != nil {
+		log.Printf("unable to locate command: '%s'", h.ExecuteCommand)
+
+		// check if parameters specified in execute-command by mistake
+		if strings.IndexByte(h.ExecuteCommand, ' ') != -1 {
+			s := strings.Fields(h.ExecuteCommand)[0]
+			log.Printf("use 'pass-arguments-to-command' to specify args for '%s'", s)
+		}
+
+		return "", err
+	}
+
+	cmd := exec.Command(cmdPath)
 	cmd.Dir = h.CommandWorkingDirectory
 
 	cmd.Args, errors = h.ExtractCommandArguments(headers, query, payload)

webhook_test.go

@@ -1,13 +1,16 @@
 package main
 
 import (
+	"bytes"
 	"fmt"
 	"io/ioutil"
+	"log"
 	"net"
 	"net/http"
 	"os"
 	"os/exec"
 	"path/filepath"
+	"regexp"
 	"runtime"
 	"strings"
 	"testing"
@@ -17,6 +20,91 @@ import (
 	"github.com/adnanh/webhook/hook"
 )
 
+func TestStaticParams(t *testing.T) {
+
+	spHeaders := make(map[string]interface{})
+	spHeaders["User-Agent"] = "curl/7.54.0"
+	spHeaders["Accept"] = "*/*"
+
+	// case 1: correct entry
+	spHook := &hook.Hook{
+		ID:                      "static-params-ok",
+		ExecuteCommand:          "/bin/echo",
+		CommandWorkingDirectory: "/tmp",
+		ResponseMessage:         "success",
+		CaptureCommandOutput:    true,
+		PassArgumentsToCommand: []hook.Argument{
+			hook.Argument{Source: "string", Name: "passed"},
+		},
+	}
+
+	b := &bytes.Buffer{}
+	log.SetOutput(b)
+
+	s, err := handleHook(spHook, &spHeaders, &map[string]interface{}{}, &map[string]interface{}{}, &[]byte{})
+	if err != nil {
+		t.Fatalf("Unexpected error: %v\n", err)
+	}
+	matched, _ := regexp.MatchString("(?s).*command output: passed.*static-params-ok", b.String())
+	if !matched {
+		t.Fatalf("Unexpected log output:\n%s", b)
+	}
+
+	// case 2: binary with spaces in its name
+	err = os.Symlink("/usr/bin/true", "/tmp/with space")
+	if err != nil {
+		t.Fatalf("%v", err)
+	}
+	defer os.Remove("/tmp/with space")
+
+	spHook = &hook.Hook{
+		ID:                      "static-params-name-space",
+		ExecuteCommand:          "/tmp/with space",
+		CommandWorkingDirectory: "/tmp",
+		ResponseMessage:         "success",
+		CaptureCommandOutput:    true,
+		PassArgumentsToCommand: []hook.Argument{
+			hook.Argument{Source: "string", Name: "passed"},
+		},
+	}
+
+	b = &bytes.Buffer{}
+	log.SetOutput(b)
+
+	s, err = handleHook(spHook, &spHeaders, &map[string]interface{}{}, &map[string]interface{}{}, &[]byte{})
+	if err != nil {
+		t.Fatalf("Unexpected error: %v\n", err)
+	}
+	matched, _ = regexp.MatchString("(?s)command output: .*static-params-name-space", b.String())
+	if !matched {
+		t.Fatalf("Unexpected log output:\n%sn", b)
+	}
+
+	// case 3: parameters specified in execute-command
+	spHook = &hook.Hook{
+		ID:                      "static-params-bad",
+		ExecuteCommand:          "/bin/echo success",
+		CommandWorkingDirectory: "/tmp",
+		ResponseMessage:         "success",
+		CaptureCommandOutput:    true,
+		PassArgumentsToCommand: []hook.Argument{
+			hook.Argument{Source: "string", Name: "failed"},
+		},
+	}
+
+	b = &bytes.Buffer{}
+	log.SetOutput(b)
+
+	s, err = handleHook(spHook, &spHeaders, &map[string]interface{}{}, &map[string]interface{}{}, &[]byte{})
+	if err == nil {
+		t.Fatalf("Error expected, but none returned: %s\n", s)
+	}
+	matched, _ = regexp.MatchString("(?s)unable to locate command: ..bin.echo success.*use 'pass-arguments-to-command'", b.String())
+	if !matched {
+		t.Fatalf("Unexpected log output:\n%s\n", b)
+	}
+}
+
 func TestWebhook(t *testing.T) {
 	hookecho, cleanupHookecho := buildHookecho(t)
 	defer cleanupHookecho()