query-node: make Channel.language nullable

query-node/mappings/content-directory/entity/create.ts

@@ -74,7 +74,7 @@ async function createChannel(
 
   channel.happenedIn = await createBlockOrGetFromDatabase(db, block)
   const { language } = p
-  if (language !== undefined) {
+  if (language) {
     channel.language = await getOrCreate.language(
       { db, block, id },
       classEntityMap,

query-node/mappings/content-directory/entity/update.ts

@@ -98,8 +98,8 @@ async function updateChannelEntityPropertyValues(
   const record = await db.get(Channel, where)
   if (record === undefined) throw Error(`Entity not found: ${where.where.id}`)
 
-  let lang: Language | undefined
-  if (props.language !== undefined) {
+  let lang: Language | undefined = record.language
+  if (props.language) {
     const id = getEntityIdFromReferencedField(props.language, entityIdBeforeTransaction)
     lang = await db.get(Language, { where: { id } })
     if (lang === undefined) throw Error(`Language entity not found: ${id}`)
@@ -107,7 +107,7 @@ async function updateChannelEntityPropertyValues(
   }
   Object.assign(record, props)
 
-  record.language = lang || record.language
+  record.language = lang
   await db.save<Channel>(record)
 }
 async function updateVideoMediaEntityPropertyValues(

query-node/schema.graphql

@@ -102,7 +102,7 @@ type Channel @entity {
   isCurated: Boolean!
 
   "The primary langauge of the channel's content"
-  language: Language!
+  language: Language
 
   videos: [Video!] @derivedFrom(field: "channel")