From 5a4398f690a688baac0223cfd80d10f199cb4425 Mon Sep 17 00:00:00 2001
From: mike12345567 <me@michaeldrury.co.uk>
Date: Mon, 28 Jun 2021 17:42:39 +0100
Subject: [PATCH] Some work towards supporting many SQL relationships.

---
 .../DataTable/modals/CreateEditColumn.svelte  |  2 +-
 .../src/api/controllers/row/external.js       | 28 +++++++++++--------
 packages/string-templates/src/index.cjs       |  7 +----
 3 files changed, 19 insertions(+), 18 deletions(-)

diff --git a/packages/builder/src/components/backend/DataTable/modals/CreateEditColumn.svelte b/packages/builder/src/components/backend/DataTable/modals/CreateEditColumn.svelte
index 306c1cc90a..35722481db 100644
--- a/packages/builder/src/components/backend/DataTable/modals/CreateEditColumn.svelte
+++ b/packages/builder/src/components/backend/DataTable/modals/CreateEditColumn.svelte
@@ -53,7 +53,7 @@
   let deletion
 
   $: tableOptions = $tables.list.filter(
-    table => table._id !== $tables.draft._id
+    table => table._id !== $tables.draft._id && table.type !== "external"
   )
   $: required = !!field?.constraints?.presence || primaryDisplay
   $: uneditable =
diff --git a/packages/server/src/api/controllers/row/external.js b/packages/server/src/api/controllers/row/external.js
index a5180a1436..879e576746 100644
--- a/packages/server/src/api/controllers/row/external.js
+++ b/packages/server/src/api/controllers/row/external.js
@@ -3,7 +3,6 @@ const {
   DataSourceOperation,
   SortDirection,
   FieldTypes,
-  RelationshipTypes,
 } = require("../../../constants")
 const { getAllExternalTables } = require("../table/utils")
 const {
@@ -137,22 +136,29 @@ function buildFilters(id, filters, table) {
   }
 }
 
-function buildRelationships(table) {
+function buildRelationships(table, allTables) {
   const relationships = []
   for (let [fieldName, field] of Object.entries(table.schema)) {
     if (field.type !== FieldTypes.LINK) {
       continue
     }
-    // TODO: through field
-    if (field.relationshipType === RelationshipTypes.MANY_TO_MANY) {
+    const { tableName: linkTableName } = breakExternalTableId(field.tableId)
+    const linkTable = allTables.find(table => table._id === field.tableId)
+    // no table to link to, this is not a valid relationships
+    if (!linkTable) {
       continue
     }
-    const broken = breakExternalTableId(field.tableId)
-    relationships.push({
-      from: fieldName,
-      to: field.fieldName,
-      tableName: broken.tableName,
-    })
+    const definition = {
+      from: fieldName || table.primary,
+      to: field.fieldName || linkTable.primary,
+      tableName: linkTableName,
+      through: undefined,
+    }
+    if (field.through) {
+      const { tableName: throughTableName } = breakExternalTableId(field.through)
+      definition.through = throughTableName
+    }
+    relationships.push(definition)
   }
   return relationships
 }
@@ -171,7 +177,7 @@ async function handleRequest(
   }
   // clean up row on ingress using schema
   filters = buildFilters(id, filters, table)
-  const relationships = buildRelationships(table)
+  const relationships = buildRelationships(table, tables)
   row = inputProcessing(row, table)
   if (
     operation === DataSourceOperation.DELETE &&
diff --git a/packages/string-templates/src/index.cjs b/packages/string-templates/src/index.cjs
index 7dbd788819..573ea76f12 100644
--- a/packages/string-templates/src/index.cjs
+++ b/packages/string-templates/src/index.cjs
@@ -1,12 +1,7 @@
 const handlebars = require("handlebars")
 const { registerAll } = require("./helpers/index")
 const processors = require("./processors")
-const { cloneDeep } = require("lodash/fp")
-const {
-  removeNull,
-  updateContext,
-  removeHandlebarsStatements,
-} = require("./utilities")
+const { removeHandlebarsStatements } = require("./utilities")
 const manifest = require("../manifest.json")
 
 const hbsInstance = handlebars.create()