firestore-repl

Interactive Firestore REPL using the JS SDK. `index.js` has one example per CRUD op, and `repl.js` gives you a shell so you can try queries without touching files every time.

TOC

• Before you run anything
• Scripts
• index.js
• repl.js
  • Using the REPL
• simple tutorial

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Before you run anything

1. Clone / open the project, then install deps:

   pnpm install

2. Copy .env.example to .env and fill the FIREBASE_* env vars. Same values as the Firebase web app config in the console. firebase.js reads them at startup so without them you’ll get a clear error listing what’s missing.

3. Create a Firestore database in the console if you haven’t...

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Scripts

pnpm start runs node index.js: by default the full all flow.

pnpm repl opens the interactive Firestore shell.

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index.js

Each op is a function (createExample, readExample, etc.) on the users collection.

# default: same as "all"
node index.js       

node index.js create

node index.js read

# first doc if you omit id
node index.js update

node index.js update <docId>

# first doc if you omit id
node index.js delete

node index.js delete <docId>

node index.js all

If you typo the mode, it prints usage and exits with code 1.

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repl.js

Run pnpm repl or node repl.js. You get a firestore> prompt. Type normal async JS that uses the Firestore helpers (db, collection, addDoc, getDocs, query, where, etc.) are already there, so you can paste stuff straight from the Firebase docs.

Using the REPL

On launch it clears the terminal and shows a small header plus hint lines, nothing fancy.

Built in words (not JavaScript, the repl catches these before it tries to run code):

• help or ? redraws that screen and adds an examples section underneath with a few snippets and short # comments above each one so you know what they’re for.
• clear, cls, clc, or the two words clear screen wipe the screen.
• exit, quit, or .exit quit the repl and close the Firestore connection.

Actual JS: your input runs inside an async function, so await getDocs(collection(db, "users")) and other Firestore calls work the way you’d expect. Paste from the docs and you’re usually fine. If you squash two statements onto one line, use a semicolon between them. Stuff like cls only works as the built in command above, it isn’t a global in Node.

Multiline: end a line with \, press enter, keep typing on the next line.

Seeing results: use console.log(...) when you care about printing, or make sure the last expression returns something, because the repl prints the return value with util.inspect when it isn’t undefined.

It's basically eval behind the scenes, so only run code you trust. Fine for your machine, bad for untrusted input!

That's it. If something breaks, check network, Firebase rules, and that .env matches the project you think you’re using.

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simple tutorial

Simple example you can paste in pnpm repl (all await because the repl runs your input as async code). Swap users / ids for whatever you use.

What	Example
Add a doc, id generated by Firestore	await addDoc(collection(db, "users"), { name: "tester" })
Set or overwrite one doc with a fixed id	await setDoc(doc(db, "users", "somekey"), { name: "tester" })
Read one doc	console.log((await getDoc(doc(db, "users", "somekey"))).data())
List every doc in a collection	;(await getDocs(collection(db, "users"))).forEach((d) => console.log(d.id, d.data()))
Update fields on a doc	await updateDoc(doc(db, "users", "somekey"), { name: "renamed" })
Delete a doc	await deleteDoc(doc(db, "users", "somekey"))
Query with a filter	;(await getDocs(query(collection(db, "users"), where("name", "==", "tester"), limit(10)))).forEach((d) => console.log(d.id, d.data()))

If a line starts with ( you may need a leading ; so JavaScript doesn’t treat it as a call on the previous line. Same idea as in the browser console.