Standardise fetching schema from client apps to fix issues with determing schema for certain data sources

packages/client/src/api/datasources.js

@@ -1,8 +1,8 @@
 import { cloneDeep } from "lodash/fp"
-import { fetchTableData } from "./tables"
+import { fetchTableData, fetchTableDefinition } from "./tables"
 import { fetchViewData } from "./views"
 import { fetchRelationshipData } from "./relationships"
-import { executeQuery } from "./queries"
+import { executeQuery, fetchQueryDefinition } from "./queries"
 
 /**
  * Fetches all rows for a particular Budibase data source.
@@ -39,3 +39,35 @@ export const fetchDatasource = async dataSource => {
   // Enrich the result is always an array
   return Array.isArray(rows) ? rows : []
 }
+
+/**
+ * Fetches the schema of any kind of datasource.
+ */
+export const fetchDatasourceSchema = async dataSource => {
+  if (!dataSource) {
+    return null
+  }
+  const { type } = dataSource
+
+  // Nested providers should already have exposed their own schema
+  if (type === "provider") {
+    return dataSource.value?.schema
+  }
+
+  // Tables, views and links can be fetched by table ID
+  if (
+    (type === "table" || type === "view" || type === "link") &&
+    dataSource.tableId
+  ) {
+    const table = await fetchTableDefinition(dataSource.tableId)
+    return table?.schema
+  }
+
+  // Queries can be fetched by query ID
+  if (type === "query" && dataSource._id) {
+    const definition = await fetchQueryDefinition(dataSource._id)
+    return definition?.schema
+  }
+
+  return null
+}

packages/client/src/api/queries.js

@@ -5,7 +5,7 @@ import API from "./api"
  * Executes a query against an external data connector.
  */
 export const executeQuery = async ({ queryId, parameters }) => {
-  const query = await API.get({ url: `/api/queries/${queryId}` })
+  const query = await fetchQueryDefinition(queryId)
   if (query?.datasourceId == null) {
     notificationStore.actions.error("That query couldn't be found")
     return
@@ -24,3 +24,10 @@ export const executeQuery = async ({ queryId, parameters }) => {
   }
   return res
 }
+
+/**
+ * Fetches the definition of an external query.
+ */
+export const fetchQueryDefinition = async queryId => {
+  return await API.get({ url: `/api/queries/${queryId}`, cache: true })
+}

packages/client/src/components/app/DataProvider.svelte

@@ -156,34 +156,24 @@
   }
 
   const getSchema = async dataSource => {
-    if (dataSource?.schema) {
-      schema = dataSource.schema
-    } else if (dataSource?.tableId) {
-      const definition = await API.fetchTableDefinition(dataSource.tableId)
-      schema = definition?.schema ?? {}
-    } else if (dataSource?.type === "provider") {
-      schema = dataSource.value?.schema ?? {}
-    } else {
-      schema = {}
-    }
+    let newSchema = (await API.fetchDatasourceSchema(dataSource)) || {}
 
     // Ensure there are "name" properties for all fields and that field schema
     // are objects
-    let fixedSchema = {}
-    Object.entries(schema || {}).forEach(([fieldName, fieldSchema]) => {
+    Object.entries(newSchema).forEach(([fieldName, fieldSchema]) => {
       if (typeof fieldSchema === "string") {
-        fixedSchema[fieldName] = {
+        newSchema[fieldName] = {
           type: fieldSchema,
           name: fieldName,
         }
       } else {
-        fixedSchema[fieldName] = {
+        newSchema[fieldName] = {
           ...fieldSchema,
           name: fieldName,
         }
       }
     })
-    schema = fixedSchema
+    schema = newSchema
     schemaLoaded = true
   }
 

packages/client/src/components/app/forms/Form.svelte

@@ -34,25 +34,34 @@
     return closestContext || {}
   }
 
-  // Fetches the form schema from this form's dataSource, if one exists
+  // Fetches the form schema from this form's dataSource
   const fetchSchema = async () => {
-    if (!dataSource?.tableId) {
+    if (!dataSource) {
       schema = {}
-      table = null
-    } else {
-      table = await API.fetchTableDefinition(dataSource?.tableId)
-      if (table) {
-        if (dataSource?.type === "query") {
-          schema = {}
-          const params = table.parameters || []
+    }
+
+    // If the datasource is a query, then we instead use a schema of the query
+    // parameters rather than the output schema
+    else if (
+      dataSource.type === "query" &&
+      dataSource._id &&
+      actionType === "Create"
+    ) {
+      const query = await API.fetchQueryDefinition(dataSource._id)
+      let paramSchema = {}
+      const params = query.parameters || []
       params.forEach(param => {
-            schema[param.name] = { ...param, type: "string" }
+        paramSchema[param.name] = { ...param, type: "string" }
       })
-        } else {
-          schema = table.schema || {}
-        }
+      schema = paramSchema
     }
+
+    // For all other cases, just grab the normal schema
+    else {
+      const dataSourceSchema = await API.fetchDatasourceSchema(dataSource)
+      schema = dataSourceSchema || {}
     }
+
     loaded = true
   }