Revert "Add GET endpoints for getting the state of the finder"

This reverts commit 750b2a6313.

This can cause a deadlock if the endpoints are accessed in the core event
loop via execute action.

  fzf --listen 6266 --bind 'space:execute:curl localhost:6266'

Technically, there's no reason to use the API because the information is
already available via `{}` and `{q}`, but I'd like to completely remove
the risk of misuse.

CHANGELOG.md

@@ -4,20 +4,13 @@ CHANGELOG
 0.36.0
 ------
 - Added `--listen=HTTP_PORT` option to start HTTP server. It allows external
-  processes to send actions to perform via POST method, or retrieve the
-  current state of the finder.
+  processes to send actions to perform via POST method.
   ```sh
   # Start HTTP server on port 6266
   fzf --listen 6266
 
-  # Send action to the server via POST method
-  curl localhost:6266 -d 'reload(seq 100)+change-prompt(hundred> )'
-
-  # Retrieve the current item
-  curl localhost:6266
-
-  # Retrieve the query string
-  curl localhost:6266/query
+  # Send actions to the server
+  curl -XPOST localhost:6266 -d 'reload(seq 100)+change-prompt(hundred> )'
   ```
 - Added `next-selected` and `prev-selected` actions to move between selected
   items

man/man1/fzf.1

@@ -723,21 +723,14 @@ e.g. \fBfzf --multi | fzf --sync\fR
 .TP
 .B "--listen=HTTP_PORT"
 Start HTTP server on the given port. It allows external processes to send
-actions to perform via POST method, or retrieve the current state of the
-finder.
+actions to perform via POST method.
 
 e.g.
      \fB# Start HTTP server on port 6266
      fzf --listen 6266
 
-     # Send action to the server via POST method
-     curl localhost:6266 -d 'reload(seq 100)+change-prompt(hundred> )'
-
-     # Retrieve the current item
-     curl localhost:6266
-
-     # Retrieve the query string
-     curl localhost:6266/query
+     # Send action to the server
+     curl -XPOST localhost:6266 -d 'reload(seq 100)+change-prompt(hundred> )'
      \fR
 
 The port number is exported as \fB$FZF_LISTEN_PORT\fR on the child processes.

src/options.go

@@ -113,7 +113,7 @@ const usage = `usage: fzf [options]
     --read0                Read input delimited by ASCII NUL characters
     --print0               Print output delimited by ASCII NUL characters
     --sync                 Synchronous search for multi-staged filtering
-    --listen=HTTP_PORT     Start HTTP server to receive actions
+    --listen=HTTP_PORT     Start HTTP server to receive actions (POST /)
     --version              Display version information and exit
 
   Environment variables

src/server.go

@@ -6,7 +6,6 @@ import (
 	"errors"
 	"fmt"
 	"net"
-	"regexp"
 	"strconv"
 	"strings"
 	"time"
@@ -14,18 +13,13 @@ import (
 
 const (
 	crlf             = "\r\n"
-	httpPattern      = "^(GET|POST) (/[^ ]*) HTTP"
 	httpOk           = "HTTP/1.1 200 OK" + crlf
 	httpBadRequest   = "HTTP/1.1 400 Bad Request" + crlf
 	httpReadTimeout  = 10 * time.Second
 	maxContentLength = 1024 * 1024
 )
 
-var (
-	httpRegexp *regexp.Regexp
-)
-
-func startHttpServer(port int, requestChan chan []*action, responseChan chan string) error {
+func startHttpServer(port int, channel chan []*action) error {
 	if port == 0 {
 		return nil
 	}
@@ -35,7 +29,6 @@ func startHttpServer(port int, requestChan chan []*action, responseChan chan str
 		return fmt.Errorf("port not available: %d", port)
 	}
 
-	httpRegexp = regexp.MustCompile(httpPattern)
 	go func() {
 		for {
 			conn, err := listener.Accept()
@@ -46,7 +39,7 @@ func startHttpServer(port int, requestChan chan []*action, responseChan chan str
 					continue
 				}
 			}
-			conn.Write([]byte(handleHttpRequest(conn, requestChan, responseChan)))
+			conn.Write([]byte(handleHttpRequest(conn, channel)))
 			conn.Close()
 		}
 		listener.Close()
@@ -61,14 +54,12 @@ func startHttpServer(port int, requestChan chan []*action, responseChan chan str
 // * No --listen:            2.8MB
 // * --listen with net/http: 5.7MB
 // * --listen w/o net/http:  3.3MB
-func handleHttpRequest(conn net.Conn, requestChan chan []*action, responseChan chan string) string {
+func handleHttpRequest(conn net.Conn, channel chan []*action) string {
 	contentLength := 0
 	body := ""
-	response := func(header string, message string) string {
-		return header + fmt.Sprintf("Content-Length: %d%s", len(message), crlf+crlf+message)
-	}
 	bad := func(message string) string {
-		return response(httpBadRequest, strings.TrimSpace(message)+"\n")
+		message += "\n"
+		return httpBadRequest + fmt.Sprintf("Content-Length: %d%s", len(message), crlf+crlf+message)
 	}
 	conn.SetReadDeadline(time.Now().Add(httpReadTimeout))
 	scanner := bufio.NewScanner(conn)
@@ -89,13 +80,8 @@ func handleHttpRequest(conn net.Conn, requestChan chan []*action, responseChan c
 		text := scanner.Text()
 		switch section {
 		case 0:
-			httpMatch := httpRegexp.FindStringSubmatch(text)
-			if len(httpMatch) != 3 {
-				return bad("invalid HTTP request: " + text)
-			}
-			if httpMatch[1] == "GET" {
-				requestChan <- []*action{{t: actEvaluate, a: httpMatch[2][1:]}}
-				return response(httpOk, <-responseChan)
+			if !strings.HasPrefix(text, "POST / HTTP") {
+				return bad("invalid request method")
 			}
 			section++
 		case 1:
@@ -134,6 +120,7 @@ func handleHttpRequest(conn net.Conn, requestChan chan []*action, responseChan c
 	if len(actions) == 0 {
 		return bad("no action specified")
 	}
-	requestChan <- actions
+
+	channel <- actions
 	return httpOk
 }

src/terminal.go

@@ -201,8 +201,7 @@ type Terminal struct {
 	sigstop            bool
 	startChan          chan fitpad
 	killChan           chan int
-	serverRequestChan  chan []*action
-	serverResponseChan chan string
+	serverChan         chan []*action
 	slab               *util.Slab
 	theme              *tui.ColorTheme
 	tui                tui.Renderer
@@ -277,7 +276,6 @@ const (
 	actDeleteChar
 	actDeleteCharEOF
 	actEndOfLine
-	actEvaluate
 	actForwardChar
 	actForwardWord
 	actKillLine
@@ -601,8 +599,7 @@ func NewTerminal(opts *Options, eventBox *util.EventBox) *Terminal {
 		theme:              opts.Theme,
 		startChan:          make(chan fitpad, 1),
 		killChan:           make(chan int),
-		serverRequestChan:  make(chan []*action),
-		serverResponseChan: make(chan string),
+		serverChan:         make(chan []*action),
 		tui:                renderer,
 		initFunc:           func() { renderer.Init() },
 		executing:          util.NewAtomicBool(false)}
@@ -624,7 +621,7 @@ func NewTerminal(opts *Options, eventBox *util.EventBox) *Terminal {
 		t.separator, t.separatorLen = t.ansiLabelPrinter(bar, &tui.ColSeparator, true)
 	}
 
-	if err := startHttpServer(t.listenPort, t.serverRequestChan, t.serverResponseChan); err != nil {
+	if err := startHttpServer(t.listenPort, t.serverChan); err != nil {
 		errorExit(err.Error())
 	}
 
@@ -2534,7 +2531,7 @@ func (t *Terminal) Loop() {
 			select {
 			case event = <-eventChan:
 				needBarrier = true
-			case actions = <-t.serverRequestChan:
+			case actions = <-t.serverChan:
 				event = tui.Invalid.AsEvent()
 				needBarrier = false
 			}
@@ -2617,15 +2614,6 @@ func (t *Terminal) Loop() {
 				t.executeCommand(a.a, false, a.t == actExecuteSilent)
 			case actExecuteMulti:
 				t.executeCommand(a.a, true, false)
-			case actEvaluate:
-				response := ""
-				switch a.a {
-				case "", "current":
-					response = t.currentItem().AsString(t.ansi)
-				case "query":
-					response = string(t.input)
-				}
-				t.serverResponseChan <- response
 			case actInvalid:
 				t.mutex.Unlock()
 				return false

test/test_go.rb

@@ -2440,12 +2440,9 @@ class TestGoFZF < TestBase
   def test_listen
     tmux.send_keys 'seq 10 | fzf --listen 6266', :Enter
     tmux.until { |lines| assert_equal 10, lines.item_count }
-    Net::HTTP.post(URI('http://localhost:6266'), 'change-query(00)+reload(seq 100)+change-prompt:hundred> ')
+    Net::HTTP.post(URI('http://localhost:6266'), 'change-query(yo)+reload(seq 100)+change-prompt:hundred> ')
     tmux.until { |lines| assert_equal 100, lines.item_count }
-    tmux.until { |lines| assert_equal 'hundred> 00', lines[-1] }
-    assert_equal '100', Net::HTTP.get(URI('http://localhost:6266'))
-    assert_equal '100', Net::HTTP.get(URI('http://localhost:6266/current'))
-    assert_equal '00', Net::HTTP.get(URI('http://localhost:6266/query'))
+    tmux.until { |lines| assert_equal 'hundred> yo', lines[-1] }
   end
 end