Updated JS dependencies; fixed the problem with pluggable extensions.

project.clj

@@ -54,15 +54,15 @@
             [lein-npm "0.6.2"]
             [lein-ring "0.12.5" :exclusions [org.clojure/clojure]]]
 
-  :npm {:dependencies [[simplemde "1.11.2"]
-                       [vega "5.9.0"]
-                       [vega-embed "6.2.2"]
-                       [vega-lite "4.1.1"]
-                       [mermaid "8.4.6"]
+  :npm {:dependencies [[geocsv-js "simon-brooke/geocsv-js#3a34ba7"]
+                       [mermaid "8.13.8"]
                        [photoswipe "4.1.3"]
+                       [simplemde "1.11.2"]
                        [showdown "1.9.1"]
-                       [tablesort "5.2.0"]
-                       [geocsv-js "simon-brooke/geocsv-js#3a34ba7"]]
+                       [tablesort "5.3.0"]
+                       [vega "5.21.0"]
+                       [vega-embed "6.20.5"]
+                       [vega-lite "5.2.0"]]
         :root "resources/public/vendor"}
 
   :docker {:image-name "simonbrooke/smeagol"

resources/public/content/Extensible Markup.md

@@ -146,7 +146,9 @@ followed by three backticks on a line by themselves. There is an [[Example galle
 
 ## Writing your own custom formatters
 
-A custom formatter is simply a Clojure function which takes a string and an integer as arguments and produces a string as output. The string is the text the user has typed into their markdown; the integer is simply a number you can use to keep track of which addition to the page this is, in order, for example, to fix up some JavaScript to render it.
+A custom formatter is simply a Clojure function which takes a string and an integer as arguments and produces a string as output. The string argument is the text the user has typed into their markdown; the integer is simply a number you can use to keep track of which addition to the page this is, in order, for example, to fix up some JavaScript to render it.
+
+The string returned should just be the necessary HTML text to add to the page to invoke the formatter.
 
 For example, here's the formatter which handles the Vega charts:
 
@@ -166,6 +168,10 @@ For example, here's the formatter which handles the Vega charts:
         index
         ");\n//]]\n</script>"))
 				
+In order to allow pluggable extensions -- that is, extensions which are not compiled as part of Smeagol but are added as additional classes on the classpath at run time -- every extension function must be written in a namespace which has the `(:gen-class)` directive.
+
+In principal it should be possible to write extensions in Java, or in other languages which compile for the JVM, but this has not yet been demonstrated.
+
 ### Configuring Smeagol to use your formatter
 
 To add your own formatter, compile it into a jar file which is on the classpath - it does *not* have to be part of the Smeagol project directly - and then edit the value of the key `:formatters` in the file `config.edn`; whose standard definition is:

src/smeagol/extensions/geocsv.clj

@@ -3,7 +3,8 @@
   smeagol.extensions.geocsv
   (:require [smeagol.configuration :refer [config]]
             [smeagol.extensions.utils :refer [resource-url-or-data->data]]
-            [taoensso.timbre :as log]))
+            [taoensso.timbre :as log])
+  (:gen-class))
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;;;;

src/smeagol/extensions/mermaid.clj

@@ -2,7 +2,8 @@
       :author "Simon Brooke"}
   smeagol.extensions.mermaid
   (:require [smeagol.extensions.utils :refer [resource-url-or-data->data]]
-            [taoensso.timbre :as log]))
+            [taoensso.timbre :as log])
+  (:gen-class))
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;;;;

src/smeagol/extensions/photoswipe.clj

@@ -14,7 +14,8 @@
             [smeagol.configuration :refer [config]]
             [smeagol.extensions.utils :refer [resource-url-or-data->data uploaded?]]
             [smeagol.util :refer [content-dir upload-dir]]
-            [taoensso.timbre :as log]))
+            [taoensso.timbre :as log])
+  (:gen-class))
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;;;;
@@ -155,7 +156,7 @@
        {:slides (map
                  process-simple-slide
                  (simplify (simple-grammar spec)))
-           :options { :timeToIdle 100 }
+        :options {:timeToIdle 100}
         :openImmediately true}) index))))
 
 

src/smeagol/extensions/test.clj

@@ -1,6 +1,7 @@
 (ns ^{:doc "Very simple extension for testing the extension processing flow."
       :author "Simon Brooke"}
-  smeagol.extensions.test)
+  smeagol.extensions.test
+  (:gen-class))
 
 
 (def process-test-return-value "<!-- The test extension has run and this is its output -->")

src/smeagol/extensions/vega.clj

@@ -2,7 +2,8 @@
       :author "Simon Brooke"}
   smeagol.extensions.vega
   (:require [smeagol.extensions.utils :refer [resource-url-or-data->data yaml->json]]
-            [taoensso.timbre :as log]))
+            [taoensso.timbre :as log])
+  (:gen-class))
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;;;;