only offer languages that have been marked as substantially complete (#466)

This checks for languages that have a special key translated.
Any that don't have the key translated, are not offered to the
user (unless GRIST_OFFER_ALL_LANGUAGES is set).

Co-authored-by: jarek <jaroslaw.sadzinski@gmail.com>

README.md

@@ -261,6 +261,7 @@ GRIST_LIST_PUBLIC_SITES | if set to true, sites shared with the public will be l
 GRIST_MANAGED_WORKERS | if set, Grist can assume that if a url targeted at a doc worker returns a 404, that worker is gone
 GRIST_MAX_UPLOAD_ATTACHMENT_MB | max allowed size for attachments (0 or empty for unlimited).
 GRIST_MAX_UPLOAD_IMPORT_MB | max allowed size for imports (except .grist files) (0 or empty for unlimited).
+GRIST_OFFER_ALL_LANGUAGES | if set, all translated langauages are offered to the user (by default, only languages with a special 'good enough' key set are offered to user).
 GRIST_ORG_IN_PATH | if true, encode org in path rather than domain
 GRIST_PAGE_TITLE_SUFFIX | a string to append to the end of the `<title>` in HTML documents. Defaults to `" - Grist"`. Set to `_blank` for no suffix at all.
 GRIST_PROXY_AUTH_HEADER | header which will be set by a (reverse) proxy webserver with an authorized users' email. This can be used as an alternative to a SAML service. See also GRIST_FORWARD_AUTH_HEADER.

app/server/localization.ts

@@ -1,3 +1,5 @@
+import {appSettings} from 'app/server/lib/AppSettings';
+import log from 'app/server/lib/log';
 import {lstatSync, readdirSync, readFileSync} from 'fs';
 import {createInstance, i18n} from 'i18next';
 import {LanguageDetector} from 'i18next-http-middleware';
@@ -26,7 +28,7 @@ export function setupLocale(appRoot: string): i18n {
       throw new Error("Unrecognized resource file " + fileName);
     }
     supportedNamespaces.add(namespace);
-    preload.push([lang, namespace, fullPath]);
+    preload.push([namespace, lang, fullPath]);
     supportedLngs.add(lang);
   }
 
@@ -51,15 +53,32 @@ export function setupLocale(appRoot: string): i18n {
   }).catch((err: any) => {
     // This should not happen, the promise should be resolved synchronously, without
     // any errors reported.
-    console.error("i18next failed unexpectedly", err);
+    log.error("i18next failed unexpectedly", err);
   });
   if (errorDuringLoad) {
-    console.error('i18next failed to load', errorDuringLoad);
+    log.error('i18next failed to load', errorDuringLoad);
     throw errorDuringLoad;
   }
   // Load all files synchronously.
-  for(const [lng, ns, fullPath] of preload) {
-    instance.addResourceBundle(lng, ns, JSON.parse(readFileSync(fullPath, 'utf8')));
+  // First sort by ns, which will put "client" first. That lets us check for a
+  // client key which, if absent, means the language should be ignored.
+  preload.sort((a, b) => a[0].localeCompare(b[0]));
+  const offerAll = appSettings.section('locale').flag('offerAllLanguages').readBool({
+    envVar: 'GRIST_OFFER_ALL_LANGUAGES',
+  });
+  const shouldIgnoreLng = new Set<string>();
+  for(const [ns, lng, fullPath] of preload) {
+    const data = JSON.parse(readFileSync(fullPath, 'utf8'));
+    // If the "Translators: please ..." key in "App" has not been translated,
+    // ignore this language for this and later namespaces.
+    if (!offerAll && ns === 'client' &&
+      !Object.keys(data.App || {}).some(key => key.includes('Translators: please'))) {
+      shouldIgnoreLng.add(lng);
+      log.debug(`skipping incomplete language ${lng} (set GRIST_OFFER_ALL_LANGUAGES if you want it)`);
+    }
+    if (!shouldIgnoreLng.has(lng)) {
+      instance.addResourceBundle(lng, ns, data);
+    }
   }
   return instance;
 }