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diff --git a/src/wasp-bus.el b/src/wasp-bus.el
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+;;; wasp-bus --- Pub/sub bus client -*- lexical-binding: t; -*-
+;;; Commentary:
+;;; Code:
+
+(require 'dash)
+(require 's)
+(require 'wasp-utils)
+
+(defgroup wasp nil
+  "Pub/sub bus client."
+  :group 'applications)
+
+(defcustom w/bus-process "wasp-bus"
+  "Name of process connected to network bus."
+  :type '(string)
+  :group 'wasp)
+
+(defcustom w/bus-buffer " *wasp-bus*"
+  "Name of buffer used to store intermediate network data."
+  :type '(string)
+  :group 'wasp)
+
+(defcustom w/bus-host "shiro"
+  "Hostname of the bus server."
+  :type '(string)
+  :group 'wasp)
+
+(defcustom w/bus-port 32050
+  "Port of the bus server."
+  :type '(integer)
+  :group 'wasp)
+
+(defvar w/bus-event-handlers nil
+  "List of pairs of events and handler functions.")
+
+(defun w/handle-message (msg)
+  "Handle the message MSG."
+  (let* ((ev (car msg))
+         (body (cdr msg))
+         (handler (alist-get ev w/bus-event-handlers nil nil #'equal)))
+    (if handler
+        (funcall handler body)
+      (w/write-log (format "Unknown incoming event: %S" ev)))))
+
+(defun w/get-complete-line ()
+  "Kill a line followed by a newline if it exists, and nil otherwise."
+  (let ((l (thing-at-point 'line t)))
+    (if (and l (s-contains? "\n" l))
+        (progn
+          (delete-region (line-beginning-position) (line-beginning-position 2))
+          l)
+      nil)))
+(defun w/handle-lines ()
+  "Call `w/handle-message' on every complete line of the current buffer."
+  (let ((l (w/get-complete-line)))
+    (when (and l (not (s-blank? l)))
+      (w/handle-message (read (w/clean-string l)))
+      (w/handle-lines))))
+(defun w/process-filter (proc data)
+  "Process filter for pub/sub bus connection on PROC and DATA."
+  (with-current-buffer (get-buffer-create w/bus-buffer)
+    (when (not (marker-position (process-mark proc)))
+      (set-marker (process-mark proc) (point-max)))
+    (goto-char (process-mark proc))
+    (insert data)
+    (set-marker (process-mark proc) (point))
+    (goto-char (point-min))
+    (w/handle-lines)))
+
+(defun w/sub (ev)
+  "Subscribe to the event EV."
+  (process-send-string
+   w/bus-process
+   (s-concat
+    (format "%S" `(sub ,ev))
+    "\n")))
+
+(defun w/pub (ev &optional d)
+  "Publish the data D to the event EV."
+  (process-send-string
+   w/bus-process
+   (s-concat
+    (format "%S" `(pub ,ev ,@d))
+    "\n")))
+
+(defun w/sub-all ()
+  "Subscribe to all events in `w/bus-event-handlers'."
+  (--each w/bus-event-handlers
+    (w/write-log (format "Subscribing to: %S" (car it)))
+    (w/sub (car it))))
+
+(defun w/disconnect ()
+  "Disconnect from the pub/sub bus."
+  (interactive)
+  (when (process-live-p (get-process w/bus-process))
+    (delete-process w/bus-process)))
+
+(defun w/connect ()
+  "Connect to the pub/sub bus."
+  (interactive)
+  (w/disconnect)
+  (make-network-process
+   :name w/bus-process
+   :buffer nil
+   :host w/bus-host
+   :service w/bus-port
+   :filter #'w/process-filter)
+  (w/sub-all))
+
+(provide 'wasp-network)
+;;; wasp-bus.el ends here