feat(i18n) Custom i18n strings (#4000)

* Custom i18n strings (and some code formatting)

* Documentation for per-instance l10n overwrites

doc/localization.md

@@ -92,3 +92,23 @@ For example, if you want to replace `Chat` with `Notes`, simply add...
 , "pad.chat": "Notes"
 }
 ```
+
+## Customization for Administrators
+
+As an Etherpad administrator, it is possible to overwrite core mesages as well as messages in plugins. These include error messages, labels, and user instructions. Whereas the localization in the source code is in separate files separated by locale, an administrator's custom localizations are in `settings.json` under the `customLocaleStrigns` key, with each locale separated by a sub-key underneath.
+
+For example, let's say you want to change the text on the "New Pad" button on Etherpad's home page. If you look in `locales/en.json` (or `locales/en-gb.json`) you'll see the key for this text is `"index.newPad"`. You could add the following to `settings.json`:
+
+```
+  "customLocaleStrings": {
+    "fr": {
+      "index.newPad": "Créer un document"
+    },
+    "en-gb": {
+      "index.newPad": "Create a document"
+    },
+    "en": {
+      "index.newPad": "Create a document"
+    }
+  }
+```

settings.json.docker

@@ -551,5 +551,8 @@
       */
 
       ]
-    } // logconfig
+    }, // logconfig
+
+  /* Override any strings found in locale directories */
+  "customLocaleStrings": {}
 }

settings.json.template

@@ -556,5 +556,8 @@
       */
 
       ]
-    } // logconfig
+    }, // logconfig
+
+  /* Override any strings found in locale directories */
+  "customLocaleStrings": {}
 }

src/node/hooks/express/adminsettings.js

@@ -29,9 +29,9 @@ exports.socketio = function (hook_name, args, cb) {
           return console.log(err);
         }
 
-        //if showSettingsInAdminPage is set to false, then return NOT_ALLOWED in the result
+        // if showSettingsInAdminPage is set to false, then return NOT_ALLOWED in the result
         if(settings.showSettingsInAdminPage === false) {
-          socket.emit("settings", {results:'NOT_ALLOWED'});
+          socket.emit("settings", {results: 'NOT_ALLOWED'});
         }
         else {
           socket.emit("settings", {results: data});

src/node/hooks/i18n.js

@@ -6,6 +6,7 @@ var languages = require('languages4translatewiki')
   , plugins = require('ep_etherpad-lite/static/js/pluginfw/plugins.js').plugins
   , semver = require('semver')
   , existsSync = require('../utils/path_exists')
+  , settings = require('../utils/Settings');
 ;
 
 
@@ -43,7 +44,7 @@ function getAllLocales() {
   //add plugins languages (if any)
   for(var pluginName in plugins) extractLangs(path.join(npm.root, pluginName, 'locales'));
 
-  // Build a locale index (merge all locale data)
+  // Build a locale index (merge all locale data other than user-supplied overrides)
   var locales = {}
   _.each (locales2paths, function(files, langcode) {
     locales[langcode]={};
@@ -54,6 +55,22 @@ function getAllLocales() {
     });
   });
 
+  // Add custom strings from settings.json
+  // Since this is user-supplied, we'll do some extra sanity checks
+  const wrongFormatErr = Error(
+    "customLocaleStrings in wrong format. See documentation " +
+    "for Customization for Administrators, under Localization.")
+  if (settings.customLocaleStrings) {
+    if (typeof settings.customLocaleStrings !== "object") throw wrongFormatErr
+    _.each(settings.customLocaleStrings, function(overrides, langcode) {
+      if (typeof overrides !== "object") throw wrongFormatErr
+      _.each(overrides, function(localeString, key) {
+        if (typeof localeString !== "string") throw wrongFormatErr
+        locales[langcode][key] = localeString
+      })
+    })
+  }
+
   return locales;
 }
 

src/node/utils/Settings.js

@@ -321,6 +321,11 @@ exports.scrollWhenFocusLineIsOutOfViewport = {
  */
 exports.exposeVersion = false;
 
+/*
+ * Override any strings found in locale directories
+ */
+exports.customLocaleStrings = {};
+
 /*
  * From Etherpad 1.8.3 onwards, import and export of pads is always rate
  * limited.