docs: add prototype sphinx extension for online help

goes through the sections in the documents and creates the
OnlineHelpInfo.js file from the explicitly defined section labels which
are used in the js files with 'onlineHelp' variable.

docs/Makefile

@@ -28,7 +28,6 @@ COMPILEDIR := ../target/debug
 SPHINXOPTS    += -t devbuild
 endif
 
-
 # Sphinx internal variables.
 ALLSPHINXOPTS   = -d $(BUILDDIR)/doctrees $(SPHINXOPTS) .
 
@@ -68,6 +67,12 @@ proxmox-backup-manager.1: proxmox-backup-manager/man1.rst  proxmox-backup-manage
 proxmox-backup-proxy.1: proxmox-backup-proxy/man1.rst  proxmox-backup-proxy/description.rst
 	rst2man $< >$@
 
+.PHONY: onlinehelpinfo
+onlinehelpinfo:
+	@echo "Generating OnlineHelpInfo.js..."
+	$(SPHINXBUILD) -b proxmox-scanrefs $(ALLSPHINXOPTS) $(BUILDDIR)/scanrefs
+	@echo "Build finished. OnlineHelpInfo.js is in $(BUILDDIR)/scanrefs."
+
 .PHONY: html
 html: ${GENERATED_SYNOPSIS}
 	$(SPHINXBUILD) -b html $(ALLSPHINXOPTS) $(BUILDDIR)/html

docs/_ext/proxmox-scanrefs.py

@@ -0,0 +1,133 @@
+#!/usr/bin/env python3
+
+# debugging stuff
+from pprint import pprint
+
+from typing import cast
+
+import json
+import re
+
+import os
+import io
+from docutils import nodes
+
+from sphinx.builders import Builder
+from sphinx.util import logging
+
+logger = logging.getLogger(__name__)
+
+# refs are added in the following manner before the title of a section (note underscore and newline before title):
+# .. _my-label:
+#
+# Section to ref
+# --------------
+#
+#
+# then referred to like (note missing underscore):
+# "see :ref:`my-label`"
+#
+# the benefit of using this is if a label is explicitly set for a section,
+# we can refer to it with this anchor #my-label in the html,
+# even if the section name changes.
+#
+# see https://www.sphinx-doc.org/en/master/usage/restructuredtext/roles.html#role-ref
+
+def scan_extjs_files(wwwdir="../www"): # a bit rough i know, but we can optimize later
+    js_files = []
+    used_anchors = []
+    logger.info("scanning extjs files for onlineHelp definitions")
+    for root, dirs, files in os.walk("{}".format(wwwdir)):
+        #print(root, dirs, files)
+        for filename in files:
+            if filename.endswith('.js'):
+                js_files.append(os.path.join(root, filename))
+    for js_file in js_files:
+        fd = open(js_file).read()
+        match = re.search("onlineHelp:\s*[\'\"](.*?)[\'\"]", fd) # match object is tuple
+        if match:
+            anchor = match.groups()[0]
+            anchor = re.sub('_', '-', anchor) # normalize labels
+            logger.info("found onlineHelp: {} in {}".format(anchor, js_file))
+            used_anchors.append(anchor)
+    return used_anchors
+
+
+def setup(app):
+    logger.info('Mapping reference labels...')
+    app.add_builder(ReflabelMapper)
+    return {
+        'version': '0.1',
+        'parallel_read_safe': True,
+        'parallel_write_safe': True,
+    }
+
+class ReflabelMapper(Builder):
+    name = 'proxmox-scanrefs'
+
+    def init(self):
+        self.docnames = []
+        self.env.online_help = {}
+        self.env.online_help['pbs_documentation_index'] = {
+            'link': '/docs/index.html',
+            'title': 'Proxmox Backup Server Documentation Index',
+        }
+        self.env.used_anchors = scan_extjs_files()
+
+        if not os.path.isdir(self.outdir):
+            os.mkdir(self.outdir)
+
+        self.output_filename = os.path.join(self.outdir, 'OnlineHelpInfo.js')
+        self.output = io.open(self.output_filename, 'w', encoding='UTF-8')
+
+    def write_doc(self, docname, doctree):
+            for node in doctree.traverse(nodes.section):
+                #pprint(vars(node))
+
+                if hasattr(node, 'expect_referenced_by_id') and len(node['ids']) > 1: # explicit labels
+                    filename = self.env.doc2path(docname)
+                    filename_html = re.sub('.rst', '.html', filename)
+                    labelid = node['ids'][1] # [0] is predefined by sphinx, we need [1] for explicit ones
+                    title = cast(nodes.title, node[0])
+                    logger.info('traversing section {}'.format(title.astext()))
+                    ref_name = getattr(title, 'rawsource', title.astext())
+
+                    self.env.online_help[labelid] = {'link': '', 'title': ''}
+                    self.env.online_help[labelid]['link'] = "/docs/" + os.path.basename(filename_html) + "#{}".format(labelid)
+                    self.env.online_help[labelid]['title'] = ref_name
+
+            return
+
+
+    def get_outdated_docs(self):
+        return 'all documents'
+
+    def prepare_writing(self, docnames):
+        return
+
+    def get_target_uri(self, docname, typ=None):
+        return ''
+
+    def validate_anchors(self):
+        #pprint(self.env.online_help)
+        to_remove = []
+        for anchor in self.env.used_anchors:
+            if anchor not in self.env.online_help:
+                logger.info("[-] anchor {} is missing from onlinehelp!".format(anchor))
+        for anchor in self.env.online_help:
+            if anchor not in self.env.used_anchors and anchor != 'pbs_documentation_index':
+                logger.info("[*] anchor {} not used! deleting...".format(anchor))
+                to_remove.append(anchor)
+        for anchor in to_remove:
+            self.env.online_help.pop(anchor, None)
+        return
+
+    def finish(self):
+        # generate OnlineHelpInfo.js output
+        self.validate_anchors()
+
+        self.output.write("const proxmoxOnlineHelpInfo = ")
+        self.output.write(json.dumps(self.env.online_help, indent=2))
+        self.output.write(";\n")
+        self.output.close()
+        return

docs/conf.py

@@ -18,9 +18,12 @@
 # documentation root, use os.path.abspath to make it absolute, like shown here.
 #
 import os
-# import sys
+import sys
 # sys.path.insert(0, os.path.abspath('.'))
 
+# custom extensions
+sys.path.append(os.path.abspath("./_ext"))
+
 # -- Implement custom formatter for code-blocks ---------------------------
 #
 # * use smaller font
@@ -46,7 +49,7 @@ PygmentsBridge.latex_formatter = CustomLatexFormatter
 # extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
 # ones.
 
-extensions = ["sphinx.ext.graphviz", "sphinx.ext.todo"]
+extensions = ["sphinx.ext.graphviz", "sphinx.ext.todo", "proxmox-scanrefs"]
 
 todo_link_only = True
 

docs/local-zfs.rst

@@ -1,3 +1,6 @@
+
+.. _chapter-zfs:
+
 ZFS on Linux
 ------------
 

www/Makefile

@@ -54,6 +54,10 @@ all: js/proxmox-backup-gui.js css/ext6-pbs.css
 js:
 	mkdir js
 
+OnlineHelpInfo.js:
+	$(MAKE) -C ../docs onlinehelpinfo
+	mv ../docs/output/scanrefs/OnlineHelpInfo.js .
+
 js/proxmox-backup-gui.js: js OnlineHelpInfo.js ${JSSRC}
 	cat OnlineHelpInfo.js ${JSSRC} >$@.tmp
 	mv $@.tmp $@

www/OnlineHelpInfo.js

@@ -1,6 +1,10 @@
-var proxmoxOnlineHelpInfo = {
-    "pbs_documentation_index" : {
-	"link" : "/pbs-docs/index.html",
-	"title" : "Proxmox Backup Server Documentation Index"
-    }
+const proxmoxOnlineHelpInfo = {
+  "pbs_documentation_index": {
+    "link": "/pbs-docs/index.html",
+    "title": "Proxmox Backup Server Documentation Index"
+  },
+  "chapter-zfs": {
+    "link": "/docs/sysadmin.html#chapter-zfs",
+    "title": "ZFS on Linux"
+  }
 };