Add autofill backend

app/src/api/api.ts

@@ -1,6 +1,7 @@
 import bodyParser from 'body-parser';
 import express from 'express';
 
+import autofillController from './controllers/autofillController';
 import * as editHistoryController from './controllers/editHistoryController';
 import buildingsRouter from './routes/buildingsRouter';
 import extractsRouter from './routes/extractsRouter';
@@ -19,6 +20,7 @@ server.use('/users', usersRouter);
 server.use('/extracts', extractsRouter);
 
 server.get('/history', editHistoryController.getGlobalEditHistory);
+server.get('/autofill', autofillController.getAutofillOptions);
 
 // POST user auth
 server.post('/login', function (req, res) {

app/src/api/controllers/autofillController.ts

@@ -0,0 +1,14 @@
+import asyncController from '../routes/asyncController';
+import * as autofillService from '../services/autofill';
+
+const getAutofillOptions = asyncController(async (req, res) => {
+    const { field_name, field_value } = req.query;
+
+    const options = await autofillService.getAutofillOptions(field_name, field_value);
+
+    res.send(options);
+});
+
+export default {
+    getAutofillOptions
+};

app/src/api/services/autofill.ts

@@ -0,0 +1,25 @@
+import db from '../../db';
+
+const autofillFunctionMap = {
+    current_landuse_class: getLanduseClassOptions
+};
+
+function getLanduseClassOptions(value: string) {
+    return db.manyOrNone(`
+        SELECT landuse_id AS id, description as value, similarity(description, $1) AS similarity
+        FROM reference_tables.building_landuse_class
+        WHERE description % $1
+        ORDER BY similarity DESC, description
+        `, [value]
+    );
+}
+
+export function getAutofillOptions(fieldName: string, fieldValue: any) {
+    const optionsFn = autofillFunctionMap[fieldName];
+
+    if (optionsFn == undefined) {
+        throw new Error(`Autofill options not available for field '${fieldName}'`);
+    }
+
+    return optionsFn(fieldValue);
+}