Various documentation fixes.

rocicorp · Jul 2, 2021 · 0c1525f · 0c1525f
1 parent 470cb2e
commit 0c1525f
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Showing 5 changed files with 26 additions and 22 deletions.
diff --git a/doc/docs/guide-database-setup.md b/doc/docs/guide-database-setup.md
@@ -42,7 +42,7 @@ export default async (_, res) => {
     await t.none('DROP SEQUENCE IF EXISTS version');
     // Stores chat messages
     await t.none(`CREATE TABLE message (
-      id VARCHAR(20) PRIMARY KEY NOT NULL,
+      id VARCHAR(21) PRIMARY KEY NOT NULL,
       sender VARCHAR(255) NOT NULL,
       content TEXT NOT NULL,
       ord BIGINT NOT NULL,

diff --git a/doc/docs/guide-install-replicache.md b/doc/docs/guide-install-replicache.md
@@ -6,7 +6,7 @@ slug: /guide/install
 Nothing to it...
 
 ```bash
-npm install replicache replicache-react
+npm install replicache replicache-react nanoid
 ```
 
 ... well, _almost_ nothing.

diff --git a/doc/docs/guide-local-mutations.md b/doc/docs/guide-local-mutations.md
@@ -42,7 +42,7 @@ const onSubmit = e => {
   const last = messages.length && messages[messages.length - 1][1];
   const order = (last?.order ?? 0) + 1;
   rep.mutate.createMessage({
-    id: nanoid(), // From https://www.npmjs.com/package/nanoid
+    id: nanoid(),
     from: usernameRef.current.value,
     content: contentRef.current.value,
     order,

diff --git a/doc/docs/guide-remote-mutations.md b/doc/docs/guide-remote-mutations.md
@@ -15,22 +15,9 @@ export default async (req, res) => {
   const t0 = Date.now();
   try {
     await db.tx(async t => {
-      const {nextval: version} = await db.one("SELECT nextval('version')");
-      let lastMutationID = parseInt(
-        (
-          await db.oneOrNone(
-            'SELECT last_mutation_id FROM replicache_client WHERE id = $1',
-            push.clientID,
-          )
-        )?.last_mutation_id ?? '0',
-      );
+      const {nextval: version} = await t.one("SELECT nextval('version')");
+      let lastMutationID = await getLastMutationID(t, push.clientID);
 
-      if (!lastMutationID) {
-        await db.none(
-          'INSERT INTO replicache_client (id, last_mutation_id) VALUES ($1, $2)',
-          [push.clientID, lastMutationID],
-        );
-      }
       console.log('version', version, 'lastMutationID:', lastMutationID);
 
       for (const mutation of push.mutations) {
@@ -53,7 +40,7 @@ export default async (req, res) => {
 
         switch (mutation.name) {
           case 'createMessage':
-            await createMessage(db, mutation.args, version);
+            await createMessage(t, mutation.args, version);
             break;
           default:
             throw new Error(`Unknown mutation: ${mutation.name}`);
@@ -71,7 +58,7 @@ export default async (req, res) => {
         'last_mutation_id to',
         lastMutationID,
       );
-      await db.none(
+      await t.none(
         'UPDATE replicache_client SET last_mutation_id = $2 WHERE id = $1',
         [push.clientID, lastMutationID],
       );
@@ -85,8 +72,24 @@ export default async (req, res) => {
   }
 };
 
-async function createMessage(db, {id, from, content, order}, version) {
-  await db.none(
+async function getLastMutationID(t, clientID) {
+  const clientRow = await t.oneOrNone(
+    'SELECT last_mutation_id FROM replicache_client WHERE id = $1', clientID,
+  );
+  if (clientRow) {
+    return parseInt(clientRow.last_mutation_id);
+  }
+
+  console.log('Creating new client', clientID);
+  await t.none(
+    'INSERT INTO replicache_client (id, last_mutation_id) VALUES ($1, 0)',
+    clientID,
+  );
+  return 0;
+}
+
+async function createMessage(t, {id, from, content, order}, version) {
+  await t.none(
     `INSERT INTO message (
     id, sender, content, ord, version) values 
     ($1, $2, $3, $4, $5)`,

diff --git a/doc/docs/guide-render-ui.md b/doc/docs/guide-render-ui.md
@@ -17,6 +17,7 @@ Let's use a subscription to implement our chat UI. Replace `index.js` with this:
 import React, {useEffect, useRef, useState} from 'react';
 import {Replicache} from 'replicache';
 import {useSubscribe} from 'replicache-react';
+import {nanoid} from 'nanoid';
 
 export default function Home() {
   const [rep, setRep] = useState(null);