Async version check

app/src/entry-point.lisp

@@ -407,14 +407,6 @@ Copyright (c) 2016-2019 Rigetti Computing.~2%")
   (when check-libraries
     (check-libraries))
 
-  (when check-sdk-version
-    (multiple-value-bind (available-p version)
-        (sdk-update-available-p +QVM-VERSION+ :proxy proxy)
-      (when available-p
-        (format t "An update is available to the SDK. You have version ~A. ~
-Version ~A is available from https://www.rigetti.com/forest~%"
-                +QVM-VERSION+ version))))
-
   (when verbose
     (setf qvm:*transition-verbose* t))
 
@@ -540,6 +532,9 @@ Version ~A is available from https://www.rigetti.com/forest~%"
 
     ;; Server mode.
     (server
+     (when check-sdk-version
+       (asynchronously-indicate-update-availability +QVM-VERSION+ :proxy proxy))
+
      (when execute
        (format-log "Warning: Ignoring execute option: ~S" execute)
        (setf execute nil))

app/src/qvm-app-version.lisp

@@ -35,7 +35,9 @@
     :documentation "The git hash of the QVM repo.")
   )
 
-(defun latest-sdk-version (&key (proxy nil))
+(declaim (special *logger*))
+
+(defun query-latest-sdk-version (&key (proxy nil))
   "Get the latest SDK qvm version, or NIL if unavailable."
   (handler-case
       (let* ((s (drakma:http-request
@@ -49,24 +51,40 @@
           (when success
             version)))
     (usocket:ns-error (condition)
-      (with-locked-log ()
-        (cl-syslog:rfc-log (*logger* :warning "Encountered a name resolution error when fetching latest SDK version. (~A)" condition)
-          (:msgid "LOG0001")))
+      (cl-syslog:rfc-log (*logger* :warning "Encountered a name resolution error when fetching latest SDK version. (~A)" condition)
+        (:msgid "LOG0001"))
       nil)
     (usocket:socket-error (condition)
-      (with-locked-log ()
-        (cl-syslog:rfc-log (*logger* :warning "Encountered a socket error when fetching latest SDK version. (~A)" condition)
-          (:msgid "LOG0001")))
+      (cl-syslog:rfc-log (*logger* :warning "Encountered a socket error when fetching latest SDK version. (~A)" condition)
+        (:msgid "LOG0001"))
       nil)
     (sb-bsd-sockets:socket-error (condition)
-      (with-locked-log ()
-        (cl-syslog:rfc-log (*logger* :warning "Encountered a socket error when fetching latest SDK version. (~A)" condition)
-          (:msgid "LOG0001")))
+      (cl-syslog:rfc-log (*logger* :warning "Encountered a socket error when fetching latest SDK version. (~A)" condition)
+        (:msgid "LOG0001"))
       nil)))
 
 (defun sdk-update-available-p (current-version &key (proxy nil))
-  "Test whether the current QVM version is the latest SDK
+  "Test whether the current SDK version is the latest SDK
 version. Second value returned indicates the latest version."
-  (let ((latest (latest-sdk-version :proxy proxy)))
+  (let ((latest (query-latest-sdk-version :proxy proxy)))
     (values (and latest (uiop:version< current-version latest))
             latest)))
+
+(defun asynchronously-indicate-update-availability (current-version &key (proxy nil))
+  "Write to the logger the state of the software version (whether it's the latest, if there's an update, if an update couldn't be queried)."
+  (bt:make-thread
+   (lambda ()
+     (multiple-value-bind (available? latest) (sdk-update-available-p current-version :proxy proxy)
+       (cond
+         ((null latest)
+          ;; There was some kind of issue getting the version and a warning was already emitted.
+          )
+         ((not available?)
+          (cl-syslog:rfc-log (*logger* :info "This is the latest version of the SDK.")
+            (:msgid "LOG0001")))
+         (available?
+          (cl-syslog:rfc-log (*logger* :notice "An update is available to the SDK. You have version ~A. ~
+Version ~A is available from https://downloads.rigetti.com/~%"
+                                       +QVM-VERSION+ latest)
+            (:msgid "LOG0001"))))))
+   :name "Version Check"))