Convert fieldFetch

packages/frontend-core/src/fetch/FieldFetch.ts

@@ -1,9 +1,29 @@
+import { Row, TableSchema } from "@budibase/types"
 import DataFetch from "./DataFetch"
 
-export default class FieldFetch extends DataFetch {
+interface FieldDatasource {
-  async getDefinition(datasource) {
+  fieldType: "attachment" | "array"
+  value: string[] | Row[]
+}
+
+function isArrayOfStrings(value: string[] | Row[]): value is string[] {
+  return Array.isArray(value) && !!value[0] && typeof value[0] !== "object"
+}
+
+export default class FieldFetch extends DataFetch<
+  FieldDatasource,
+  { schema?: Record<string, { type: string }> }
+> {
+  getSchema(
+    _datasource: FieldDatasource,
+    definition: { schema?: TableSchema }
+  ) {
+    return definition?.schema
+  }
+
+  async getDefinition(datasource: FieldDatasource) {
     // Field sources have their schema statically defined
-    let schema
+    let schema: Record<string, { type: string }> | undefined
     if (datasource.fieldType === "attachment") {
       schema = {
         url: {
@@ -28,8 +48,8 @@ export default class FieldFetch extends DataFetch {
 
     // These sources will be available directly from context
     const data = datasource?.value || []
-    let rows
+    let rows: Row[]
-    if (Array.isArray(data) && data[0] && typeof data[0] !== "object") {
+    if (isArrayOfStrings(data)) {
       rows = data.map(value => ({ value }))
     } else {
       rows = data

packages/frontend-core/src/fetch/JSONArrayFetch.js

@@ -1,4 +1,4 @@
-import FieldFetch from "./FieldFetch.js"
+import FieldFetch from "./FieldFetch"
 import { getJSONArrayDatasourceSchema } from "../utils/json"
 
 export default class JSONArrayFetch extends FieldFetch {

packages/frontend-core/src/fetch/QueryArrayFetch.js

@@ -1,4 +1,4 @@
-import FieldFetch from "./FieldFetch.js"
+import FieldFetch from "./FieldFetch"
 import {
   getJSONArrayDatasourceSchema,
   generateQueryArraySchemas,

packages/frontend-core/src/fetch/index.ts

@@ -4,7 +4,7 @@ import ViewV2Fetch from "./ViewV2Fetch.js"
 import QueryFetch from "./QueryFetch.js"
 import RelationshipFetch from "./RelationshipFetch.js"
 import NestedProviderFetch from "./NestedProviderFetch.js"
-import FieldFetch from "./FieldFetch.js"
+import FieldFetch from "./FieldFetch"
 import JSONArrayFetch from "./JSONArrayFetch.js"
 import UserFetch from "./UserFetch.js"
 import GroupUserFetch from "./GroupUserFetch.js"