Adding support for setting java system properties (go-tika #15)

tika/server.go

@@ -24,8 +24,8 @@ import (
 	"net/url"
 	"os"
 	"os/exec"
-	"time"
 	"strconv"
+	"time"
 
 	"golang.org/x/net/context/ctxhttp"
 )
@@ -35,21 +35,25 @@ import (
 // from Start.
 // There is no need to create a Server for an already running Tika Server
 // since you can pass its URL directly to a Client.
+// Additional Java system properties can be added to a Taka Server before
+// startup by adding to the JavaProps map
+
 type Server struct {
-	jar  string
-	url  string // url is derived from port.
-	port string
-	cmd  *exec.Cmd
-	child *ChildOptions
+	jar       string
+	url       string // url is derived from port.
+	port      string
+	cmd       *exec.Cmd
+	child     *ChildOptions
+	JavaProps map[string]string
 }
 
 // ChildOptions represent command line parameters that can be used when Tika is run with the -spawnChild option.
 // If a field is less than or equal to 0, the associated flag is not included.
 type ChildOptions struct {
-	MaxFiles int
-	TaskPulseMillis int
+	MaxFiles          int
+	TaskPulseMillis   int
 	TaskTimeoutMillis int
-	PingPulseMillis int
+	PingPulseMillis   int
 	PingTimeoutMillis int
 }
 
@@ -90,9 +94,12 @@ func NewServer(jar, port string) (*Server, error) {
 	if port == "" {
 		port = "9998"
 	}
+	javaProps := make(map[string]string)
+
 	s := &Server{
-		jar:  jar,
-		port: port,
+		jar:       jar,
+		port:      port,
+		JavaProps: javaProps,
 	}
 	urlString := "http://localhost:" + s.port
 	u, err := url.Parse(urlString)
@@ -121,7 +128,15 @@ var command = exec.Command
 // Server. Start will wait for the server to be available or until ctx is
 // cancelled.
 func (s *Server) Start(ctx context.Context) error {
-	cmd := command("java", append([]string{"-jar", s.jar, "-p", s.port}, s.child.args()...)...)
+
+	//create a slice of Java system properties to be passed to the JVM
+	props := []string{}
+	for k, v := range s.JavaProps {
+		props = append(props, fmt.Sprintf("-D%s=\"%s\"", k, v))
+	}
+
+	args := append(append(props, "-jar", s.jar, "-p", s.port), s.child.args()...)
+	cmd := command("java", args...)
 
 	if err := cmd.Start(); err != nil {
 		return err
@@ -180,13 +195,13 @@ func (s *Server) Shutdown(ctx context.Context) error {
 	}
 	errChannel := make(chan error)
 	go func() {
-			select {
-			case errChannel <- s.cmd.Wait():
-			case <-ctx.Done():
-			}
+		select {
+		case errChannel <- s.cmd.Wait():
+		case <-ctx.Done():
+		}
 	}()
 	select {
-	case err := <- errChannel:
+	case err := <-errChannel:
 		if err != nil {
 			return fmt.Errorf("could not wait for server to finish: %v", err)
 		}

tika/server_test.go

@@ -224,3 +224,40 @@ func TestDownloadServerError(t *testing.T) {
 		}
 	}
 }
+
+func TestAddJavaProps(t *testing.T) {
+	path, err := os.Executable() // Use the text executable path as a dummy jar.
+	if err != nil {
+		t.Skip("cannot find current test executable")
+	}
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
+		fmt.Fprint(w, "1.14")
+	}))
+	defer ts.Close()
+	tsURL, err := url.Parse(ts.URL)
+	if err != nil {
+		t.Fatalf("error creating test server: %v", err)
+	}
+
+	s, err := NewServer(path, tsURL.Port())
+	if err != nil {
+		t.Fatalf("NewServer got error: %v", err)
+	}
+
+	want := "/tmp/stuff"
+	want2 := "Bar"
+
+	s.JavaProps["java.io.tmpdir"] = want
+	s.JavaProps["Foo"] = want2
+
+	got := s.JavaProps["java.io.tmpdir"]
+	got2 := s.JavaProps["Foo"]
+
+	if want != got {
+		t.Fatalf("Wanted: %s, Got: %s", want, got)
+	}
+
+	if want2 != got2 {
+		t.Fatalf("Wanted: %s, Got: %s", want2, got2)
+	}
+}