[#1544] Don't fallback to SSH by default for remote hosts in case of …

…a failed

direct connection

This behavior was confusing for some users and couldn't be manually configured.
Now the behavior is configurable via the new defcustom
`nrepl-use-ssh-fallback-for-remote-hosts`
and is disabled by default.

CHANGELOG.md

@@ -11,10 +11,12 @@
 * [#1860](https://github.com/clojure-emacs/cider/issues/1860): Add `cider-repl-history` to browse the REPL input history and insert elements from it into the REPL buffer.
 * Add new customization variable `cider-font-lock-reader-conditionals` which toggles syntax highlighting of reader conditional expressions based on the buffer connection.
 * Add new face `cider-reader-conditional-face` which is used to mark unused reader conditional expressions.
+* [#1544](https://github.com/clojure-emacs/cider/issues/1544): Add a new defcustom `nrepl-use-ssh-fallback-for-remote-hosts` to control the behavior of `nrepl-connect` (and in turn that of `cider-connect`) for remote hosts.
 
 ### Changes
 
 * Drop support for Emacs 24.3.
+* Don't try to use ssh automatically when connecting to remote hosts and a direct connection fails. See `nrepl-use-ssh-fallback-for-remote-hosts`.
 
 ### Bugs Fixed
 

nrepl-client.el

@@ -115,6 +115,11 @@ The `nrepl-buffer-name-separator' separates cider-repl from the project name."
   :type 'boolean
   :group 'nrepl)
 
+(defcustom nrepl-use-ssh-fallback-for-remote-hosts nil
+  "If non-nil, attempt to connect via ssh to remote hosts when unable to connect directly."
+  :type 'boolean
+  :group 'nrepl)
+
 (defcustom nrepl-sync-request-timeout 10
   "The number of seconds to wait for a sync response.
 Setting this to nil disables the timeout functionality."
@@ -513,17 +518,22 @@ and kill the process buffer."
 For local hosts use a direct connection.  For remote hosts, if
 `nrepl-force-ssh-for-remote-hosts' is nil, attempt a direct connection
 first.  If `nrepl-force-ssh-for-remote-hosts' is non-nil or the direct
-connection failed, try to start a SSH tunneled connection.  Return a plist
-of the form (:proc PROC :host \"HOST\" :port PORT) that might contain
-additional key-values depending on the connection type."
+connection failed (and `nrepl-use-ssh-fallback-for-remote-hosts' is
+non-nil), try to start a SSH tunneled connection.  Return a plist of the
+form (:proc PROC :host \"HOST\" :port PORT) that might contain additional
+key-values depending on the connection type."
   (let ((localp (if host
                     (nrepl-local-host-p host)
                   (not (file-remote-p default-directory)))))
     (if localp
         (nrepl--direct-connect (or host "localhost") port)
-      (or (and host (not nrepl-force-ssh-for-remote-hosts)
-               (nrepl--direct-connect host port 'no-error))
-          (nrepl--ssh-tunnel-connect host port)))))
+      ;; we're dealing with a remote host
+      (if (and host (not nrepl-force-ssh-for-remote-hosts))
+          (nrepl--direct-connect host port 'no-error)
+        ;; direct connection failed or `nrepl-force-ssh-for-remote-hosts' is non-nil
+        (when (or nrepl-use-ssh-fallback-for-remote-hosts
+                  nrepl-force-ssh-for-remote-hosts)
+          (nrepl--ssh-tunnel-connect host port))))))
 
 (defun nrepl--direct-connect (host port &optional no-error)
   "If HOST and PORT are given, try to `open-network-stream'.