Major restructuring of extension processors, not yet complete

resources/config.edn

@@ -33,7 +33,7 @@
   :default-locale       "en-GB"         ;; default language used for messages
   :formatters           {"vega"         smeagol.formatting/process-vega
                          "vis"          smeagol.formatting/process-vega
-                         "mermaid"      smeagol.formatting/process-mermaid
+                         "mermaid"      smeagol.extensions.mermaid/process-mermaid
                          "backticks"    smeagol.formatting/process-backticks}
   :log-level            :info           ;; the minimum logging level; one of
                                         ;; :trace :debug :info :warn :error :fatal

resources/public/content/Extensible Markup.md

@@ -36,7 +36,7 @@ Data files can be uploaded in the same way as images, by using the **upload a fi
 
 Graphs can now be embedded in a page using the [Mermaid](https://mermaid-js.github.io/mermaid/#/) graph description language. The graph description should start with a line comprising three back-ticks and then the word `mermaid`, and end with a line comprising just three backticks.
 
-Here's an example culled from the Mermaid documentation.
+Here's an example culled from the Mermaid documentation. Edit this page to see the specification.
 
 ### GANTT Chart
 
@@ -58,6 +58,14 @@ gantt
         Add to mermaid                      :1d
 ```
 
+Mermaid graph specifications can also be loaded from URLs. Here's another example; again, edit this page to see how the trick is done.
+
+### Class Diagram
+
+```mermaid
+data/classes.mermaid
+```
+
 ## 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.

resources/public/data/classes.mermaid

@@ -0,0 +1,14 @@
+classDiagram
+Class01 <|-- AveryLongClass : Cool
+Class03 *-- Class04
+Class05 o-- Class06
+Class07 .. Class08
+Class09 --> C2 : Where am i?
+Class09 --* C3
+Class09 --|> Class07
+Class07 : equals()
+Class07 : Object[] elementData
+Class01 : size()
+Class01 : int chimp
+Class01 : int gorilla
+Class08 <--> C2: Cool label

resources/templates/wiki.html

@@ -9,7 +9,7 @@
   <!-- else -->
     <!-- TODO: currently `lein npm install` fails to build packages on all platforms, and
       fails SILENTLY. Consequently setting js-from to local is not advised. Investigting. -->
-    <!-- script "vendor/mermaid/dist/mermaid.js" %}
+    <!-- script "vendor/mermaid/dist/mermaid.js" %} -->
   <!-- endifequal -->
 {% endblock %}
 

src/smeagol/extensions/mermaid.clj

@@ -0,0 +1,85 @@
+(ns ^{:doc "Format Semagol's extended markdown format."
+      :author "Simon Brooke"}
+  smeagol.extensions.mermaid
+  (:require [smeagol.extensions.utils :refer :all]
+            [taoensso.timbre :as log]))
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;;;;
+;;;; Smeagol: a very simple Wiki engine.
+;;;;
+;;;; This program is free software; you can redistribute it and/or
+;;;; modify it under the terms of the GNU General Public License
+;;;; as published by the Free Software Foundation; either version 2
+;;;; of the License, or (at your option) any later version.
+;;;;
+;;;; This program is distributed in the hope that it will be useful,
+;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;;; GNU General Public License for more details.
+;;;;
+;;;; You should have received a copy of the GNU General Public License
+;;;; along with this program; if not, write to the Free Software
+;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
+;;;; USA.
+;;;;
+;;;; Copyright (C) 2017 Simon Brooke
+;;;;
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;;;;
+;;;; Graphs can now be embedded in a page using the
+;;;; [Mermaid](https://mermaid-js.github.io/mermaid/#/) graph description
+;;;; language. The graph description should start with a line comprising three
+;;;; back-ticks and then the word `mermaid`, and end with a line comprising just
+;;;; three backticks.
+;;;;
+;;;; Here's an example culled from the Mermaid documentation.
+;;;;
+;;;; ### GANTT Chart
+;;;;
+;;;; ```mermaid
+;;;; gantt
+;;;;         dateFormat  YYYY-MM-DD
+;;;;         title Adding GANTT diagram functionality to mermaid
+;;;;         section A section
+;;;;         Completed task            :done,    des1, 2014-01-06,2014-01-08
+;;;;         Active task               :active,  des2, 2014-01-09, 3d
+;;;;         Future task               :         des3, after des2, 5d
+;;;;         Future task2               :         des4, after des3, 5d
+;;;;         section Critical tasks
+;;;;         Completed task in the critical line :crit, done, 2014-01-06,24h
+;;;;         Implement parser and jison          :crit, done, after des1, 2d
+;;;;         Create tests for parser             :crit, active, 3d
+;;;;         Future task in critical line        :crit, 5d
+;;;;         Create tests for renderer           :2d
+;;;;         Add to mermaid                      :1d
+;;;; ```
+;;;;
+;;;; Mermaid graph specifications can also be loaded from URLs. Here's another
+;;;; example.
+;;;;
+;;;; ### Class Diagram
+;;;;
+;;;; ```mermaid
+;;;; http://localhost:3000/data/classes.mermaid
+;;;; ```
+;;;;
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+
+(defn process-mermaid
+  "If this `url-or-graph-spec` is a valid URL, it is assumed to point to a plain
+  text file pointing to a valid `graph-spec`; otherwise, it is expected to BE a
+  valid `graph-spec`.
+
+  Lightly mung this `graph-spec`, assumed to be a mermaid specification."
+  [^String url-or-graph-spec ^Integer index]
+  (let [data (resource-url-or-data->data url-or-graph-spec)
+        graph-spec (:data data)]
+    (log/info "Retrieved graph-spec from " (:from data) " `" ((:from data) data) "`")
+    (str "<div class=\"mermaid data-visualisation\" id=\"mermaid" index "\">\n"
+         graph-spec
+         "\n</div>")))
+
+;; (fs/file? (str (nio/resource-path) "data/classes.mermaid"))
+;;  (slurp (str (nio/resource-path) "data/classes.mermaid"))

src/smeagol/extensions/utils.clj

@@ -0,0 +1,72 @@
+(ns ^{:doc "Utility functions useful to extension processors."
+      :author "Simon Brooke"}
+  smeagol.extensions.utils
+  (:require [cemerick.url :refer (url url-encode url-decode)]
+            [clojure.string :as cs]
+            [me.raynes.fs :as fs]
+            [noir.io :as io]
+            [taoensso.timbre :as log]))
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;;;;
+;;;; Smeagol: a very simple Wiki engine.
+;;;;
+;;;; This program is free software; you can redistribute it and/or
+;;;; modify it under the terms of the GNU General Public License
+;;;; as published by the Free Software Foundation; either version 2
+;;;; of the License, or (at your option) any later version.
+;;;;
+;;;; This program is distributed in the hope that it will be useful,
+;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;;; GNU General Public License for more details.
+;;;;
+;;;; You should have received a copy of the GNU General Public License
+;;;; along with this program; if not, write to the Free Software
+;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
+;;;; USA.
+;;;;
+;;;; Copyright (C) 2017 Simon Brooke
+;;;;
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+(defn resource-url-or-data->data
+  "Interpret this `resource-url-or-data` string as data to be digested by a
+  `process-extension` function. It may be a URL or the pathname of a local
+  resource, in which case the content should be fetched; or it may just be
+  the data itself.
+
+  Returns a map with a key `:from` whose value may be `:url`, `:resource` or
+  `:text`, and a key `:data` whose value is the data. There will be an
+  additional key being the value of the `:from` key, whose value will be the
+  source of the data."
+  [^String resource-url-or-data]
+  (let [default {:from :text
+                 :text resource-url-or-data
+                 :data resource-url-or-data}]
+    (try
+      (try
+        ;; is it a URL?
+        (let [url (str (url resource-url-or-data))
+              result (slurp url)]
+          {:from :url
+           :url url
+           :data result})
+        (catch java.net.MalformedURLException _
+          ;; no. So is it a path to a local resource?
+          (let [t (cs/trim resource-url-or-data)
+                r (str (io/resource-path) t)]
+            (if
+              (fs/file? r)
+              {:from :resource
+               :resource t
+               :data (slurp r)}
+              default))))
+      (catch Exception x
+        (log/error
+          "Could not read mermaid graph specification from `"
+          (cs/trim resource-url-or-data)
+          "` because "
+          (.getName (.getClass x))
+          (.getMessage x) )
+        default))))

src/smeagol/formatting.clj

@@ -1,4 +1,4 @@
-(ns ^{:doc "Format Semagol's enhanced markdown format."
+(ns ^{:doc "Format Semagol's extended markdown format."
       :author "Simon Brooke"}
   smeagol.formatting
   (:require [clojure.data.json :as json]
@@ -6,7 +6,8 @@
             [cemerick.url :refer (url url-encode url-decode)]
             [clj-yaml.core :as yaml]
             [markdown.core :as md]
-            [smeagol.configuration :refer [config]]))
+            [smeagol.configuration :refer [config]]
+            [smeagol.extensions.mermaid :refer [process-mermaid]]))
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;;;;
@@ -85,12 +86,6 @@
     ");\n//]]\n</script>"))
 
 
-(defn process-mermaid
-  "Lightly mung this `graph-spec`, assumed to be a mermaid specification."
-  [^String graph-spec ^Integer index]
-  (str "<div class=\"mermaid data-visualisation\">\n"
-       graph-spec
-       "\n</div>"))
 
 
 (defn process-backticks