add --force option to raco pollen render

pollen/private/command.rkt

@@ -104,6 +104,7 @@ version                print the version" (current-server-port) (make-publish-di
   (define render-with-subdirs? (make-parameter #f))
   (define render-parallel? (make-parameter #f))
   (define special-output? (make-parameter #f))
+  (define force-render? (make-parameter #f))
   (define parsed-args
     (command-line #:program "raco pollen render"
                   #:argv (vector-drop (current-command-line-arguments) 1) ; snip the 'render' from the front
@@ -113,6 +114,7 @@ version                print the version" (current-server-port) (make-publish-di
                   [("-r" "--recursive") "Render subdirectories recursively"
                                         (render-with-subdirs? 'recursive)]
                   [("-s" "--subdir") "Render subdirectories nonrecursively" (render-with-subdirs? 'include)]
+                  [("-f" "--force") "Force render" (force-render? #true)]
                   #:once-any
                   [("-d" "--dry-run") "Print paths that would be rendered" (special-output? 'dry-run)]
                   [("-n" "--null") "Suppress file output" (special-output? 'null)]
@@ -123,7 +125,9 @@ version                print the version" (current-server-port) (make-publish-di
                   other-args))
 
   (define (handle-batch-render paths)
-    (apply render-batch (map very-nice-path paths) #:parallel (render-parallel?) #:special (special-output?)))
+    (apply render-batch (map very-nice-path paths) #:parallel (render-parallel?)
+           #:special (special-output?)
+           #:force (force-render?)))
   
   (parameterize ([current-poly-target (render-target-wanted)]) ;; applies to both cases
     (let loop ([args parsed-args])

pollen/private/ts.rktd

@@ -1 +1 @@
-1588261516
+1588447067

pollen/render.rkt

@@ -161,8 +161,10 @@
 (define current-null-output? (make-parameter #f))
 
 (define+provide/contract (render-batch #:parallel [wants-parallel-render? #false]
-                                       #:special [special-output #false] . paths-in)
-  ((#:parallel any/c) (#:special (or/c boolean? symbol?)) #:rest (listof pathish?) . ->* . void?)
+                                       #:special [special-output #false]
+                                       #:force [force-render? #false]. paths-in)
+  ((#:parallel any/c) (#:special (or/c boolean? symbol?)
+                       #:force boolean?) #:rest (listof pathish?) . ->* . void?)
   ;; Why not just (for-each render ...)?
   ;; Because certain files will pass through multiple times (e.g., templates)
   ;; And with render, they would be rendered repeatedly.
@@ -183,10 +185,10 @@
     [(null? expanded-source-paths) (message "[no paths to render]")]
     [(eq? special-output 'dry-run) (for-each message expanded-source-paths)]
     [else (parameterize ([current-null-output? (eq? special-output 'null)])
-            (for-each render-to-file-if-needed
+            (for-each (λ (sp) (render-to-file-if-needed sp #:force force-render?))
                       (match wants-parallel-render?
-                        ;; returns crashed jobs for serial rendering
                         [#false expanded-source-paths]
+                        ;; `parallel-render` returns crashed jobs for serial rendering
                         [jobs-arg (parallel-render expanded-source-paths jobs-arg)])))]))
 
 (define (pagetree->paths pagetree-or-path)    
@@ -238,7 +240,7 @@
     (define render-thunk (or maybe-render-thunk (λ () (render source-path template-path output-path)))) ; returns either string or bytes
     (define render-result
       (cond
-        [render-cache-activated?
+        [(and render-cache-activated? (not force?))
          (define key (paths->key 'output source-path template-path output-path))
          (hash-ref! ram-cache
                     ;; within a session, this will prevent repeat players like "template.html.p"
@@ -258,9 +260,9 @@
                        #:exists 'replace
                        #:mode (if (string? render-result) 'text 'binary)))))
 
-(define+provide/contract (render-to-file-if-needed source-path [maybe-template-path #f] [maybe-output-path #f] [maybe-render-thunk #f])
-  ((complete-path?) ((or/c #f complete-path?) (or/c #f complete-path?) (or/c #f procedure?)) . ->* . void?)
-  (render-to-file-base 'render-to-file-if-needed #f source-path maybe-output-path maybe-template-path maybe-render-thunk))
+(define+provide/contract (render-to-file-if-needed source-path [maybe-template-path #f] [maybe-output-path #f] [maybe-render-thunk #f] #:force [force-render? #false])
+  ((complete-path?) ((or/c #f complete-path?) (or/c #f complete-path?) (or/c #f procedure?) #:force boolean?) . ->* . void?)
+  (render-to-file-base 'render-to-file-if-needed force-render? source-path maybe-output-path maybe-template-path maybe-render-thunk))
 
 (define+provide/contract (render-to-file source-path [maybe-template-path #f] [maybe-output-path #f] [maybe-render-thunk #f])
   ((complete-path?) ((or/c #f complete-path?) (or/c #f complete-path?) (or/c #f procedure?)) . ->* . void?)

pollen/scribblings/raco.scrbl

@@ -83,6 +83,8 @@ This command can be invoked two ways: in source mode or directory mode.
 
 In both modes, the optional @exec{--dry-run} or @exec{-d} switch prints the paths that would be rendered by this command without actually doing so. 
 
+In both modes, the optional @exec{--force} or @exec{-f} switch forces a fresh render from source, even if the file is already cached.
+
 In both modes, the optional @exec{--null} or @exec{-n} switch renders as usual, but doesn't write any files. (Convenient if you're arranging special render behavior, for instance writing to a database or network server.)