eventcounter-etag-based revalidation for geodata endpoints

Author: brontolosone

lib/model/query/actees.js

@@ -16,5 +16,9 @@ const provision = (species, parent) => ({ one }) =>
   one(sql`insert into actees (id, species, parent) values (${uuid()}, ${species}, ${(parent == null) ? null : parent.acteeId}) returning *`)
     .then(construct(Actee));
 
-module.exports = { provision };
+const getEventCount = (acteeId) => ({ oneFirst }) => oneFirst(sql`
+    SELECT coalesce(sum(evt_count), 0) FROM eventcounters WHERE "acteeId" = ${acteeId}
+`);
+
+module.exports = { provision, getEventCount };
 

lib/resources/geo-extracts.js

@@ -10,7 +10,7 @@
 const { getOrNotFound } = require('../util/promise');
 const { Form } = require('../model/frames');
 const { Sanitize } = require('../util/param-sanitize');
-const { isTrue, json } = require('../util/http');
+const { isTrue, json, withEtag } = require('../util/http');
 const Problem = require('../util/problem');
 
 
@@ -37,13 +37,15 @@ module.exports = (service, endpoint) => {
 
 
   // Bulk endpoints
-  service.get('/projects/:projectId/forms/:xmlFormId/submissions.geojson', endpoint.plain(async ({ Forms, GeoExtracts }, { auth, query, params }) => {
+  service.get('/projects/:projectId/forms/:xmlFormId/submissions.geojson', endpoint.plain(async ({ Forms, GeoExtracts, Actees }, { auth, query, params }) => {
 
     const form = await Forms.getByProjectAndXmlFormId(params.projectId, params.xmlFormId, Form.WithoutDef, Form.WithoutXml)
       .then(getOrNotFound)
       .then((foundForm) => auth.canOrReject('submission.list', foundForm));
 
-    return GeoExtracts.getSubmissionFeatureCollectionGeoJson(
+    const acteeVersion = await Actees.getEventCount(form.acteeId);
+
+    const createResponse = () => GeoExtracts.getSubmissionFeatureCollectionGeoJson(
       form.id,
       Sanitize.queryParamToArray(query.submissionID),
       Sanitize.queryParamToArray(query.fieldpath),
@@ -53,15 +55,21 @@ module.exports = (service, endpoint) => {
       isTrue(query.deleted),
       Number.parseInt(query.limit, 10) || null,
     ).then(json);
+
+    // Weak etag, as the order in the resultset is undefined.
+    return withEtag(acteeVersion, createResponse, true);
   }));
 
-  service.get('/projects/:projectId/datasets/:datasetName/entities.geojson', endpoint.plain(async ({ Datasets, GeoExtracts }, { auth, query, params }) => {
+
+  service.get('/projects/:projectId/datasets/:datasetName/entities.geojson', endpoint.plain(async ({ Datasets, GeoExtracts, Actees }, { auth, query, params }) => {
 
     const foundDataset = await Datasets.get(params.projectId, params.datasetName, true)
       .then(getOrNotFound)
       .then((dataset) => auth.canOrReject('entity.list', dataset));
 
-    return GeoExtracts.getEntityFeatureCollectionGeoJson(
+    const acteeVersion = await Actees.getEventCount(foundDataset.acteeId);
+
+    const createResponse = () => GeoExtracts.getEntityFeatureCollectionGeoJson(
       foundDataset.id,
       Sanitize.queryParamToUuidArray(query.entityUUID, 'entityUUID'),
       Sanitize.queryParamToIntArray(query.creatorId, 'creatorId'),
@@ -70,6 +78,9 @@ module.exports = (service, endpoint) => {
       isTrue(query.deleted),
       Number.parseInt(query.limit, 10) || null,
     ).then(json);
+
+    // Weak etag, as the order in the resultset is undefined.
+    return withEtag(acteeVersion, createResponse, true);
   }));
 
 };