feat: Document subscriptions (#3834)

Co-authored-by: Tom Moor <tom.moor@gmail.com>

server/routes/api/subscriptions.ts

@@ -0,0 +1,141 @@
+import Router from "koa-router";
+import subscriptionCreator from "@server/commands/subscriptionCreator";
+import subscriptionDestroyer from "@server/commands/subscriptionDestroyer";
+import { sequelize } from "@server/database/sequelize";
+import auth from "@server/middlewares/authentication";
+import { Subscription, Document } from "@server/models";
+import { authorize } from "@server/policies";
+import { presentSubscription } from "@server/presenters";
+import { assertIn, assertUuid } from "@server/validation";
+import pagination from "./middlewares/pagination";
+
+const router = new Router();
+
+router.post("subscriptions.list", auth(), pagination(), async (ctx) => {
+  const { user } = ctx.state;
+  const { documentId, event } = ctx.body;
+
+  assertUuid(documentId, "documentId is required");
+
+  assertIn(
+    event,
+    ["documents.update"],
+    `Not a valid subscription event for documents`
+  );
+
+  const document = await Document.findByPk(documentId, { userId: user.id });
+
+  authorize(user, "read", document);
+
+  const subscriptions = await Subscription.findAll({
+    where: {
+      documentId: document.id,
+      userId: user.id,
+      event,
+    },
+    order: [["createdAt", "DESC"]],
+    offset: ctx.state.pagination.offset,
+    limit: ctx.state.pagination.limit,
+  });
+
+  ctx.body = {
+    pagination: ctx.state.pagination,
+    data: subscriptions.map(presentSubscription),
+  };
+});
+
+router.post("subscriptions.info", auth(), async (ctx) => {
+  const { user } = ctx.state;
+  const { documentId, event } = ctx.body;
+
+  assertUuid(documentId, "documentId is required");
+
+  assertIn(
+    event,
+    ["documents.update"],
+    "Not a valid subscription event for documents"
+  );
+
+  const document = await Document.findByPk(documentId, { userId: user.id });
+
+  authorize(user, "read", document);
+
+  // There can be only one subscription with these props.
+  const subscription = await Subscription.findOne({
+    where: {
+      userId: user.id,
+      documentId: document.id,
+      event,
+    },
+    rejectOnEmpty: true,
+  });
+
+  ctx.body = {
+    data: presentSubscription(subscription),
+  };
+});
+
+router.post("subscriptions.create", auth(), async (ctx) => {
+  const { user } = ctx.state;
+  const { documentId, event } = ctx.body;
+
+  assertUuid(documentId, "documentId is required");
+
+  assertIn(
+    event,
+    ["documents.update"],
+    "Not a valid subscription event for documents"
+  );
+
+  const subscription = await sequelize.transaction(async (transaction) => {
+    const document = await Document.findByPk(documentId, {
+      userId: user.id,
+      transaction,
+    });
+
+    authorize(user, "subscribe", document);
+
+    return subscriptionCreator({
+      user,
+      documentId: document.id,
+      event,
+      ip: ctx.request.ip,
+      transaction,
+    });
+  });
+
+  ctx.body = {
+    data: presentSubscription(subscription),
+  };
+});
+
+router.post("subscriptions.delete", auth(), async (ctx) => {
+  const { user } = ctx.state;
+  const { id } = ctx.body;
+
+  assertUuid(id, "id is required");
+
+  await sequelize.transaction(async (transaction) => {
+    const subscription = await Subscription.findByPk(id, {
+      rejectOnEmpty: true,
+      transaction,
+    });
+
+    authorize(user, "delete", subscription);
+
+    await subscriptionDestroyer({
+      user,
+      subscription,
+      ip: ctx.request.ip,
+      transaction,
+    });
+
+    return subscription;
+  });
+
+  ctx.body = {
+    success: true,
+  };
+});
+
+export default router;