CLI

This reference lists common fireemu commands and options. Run npx fireemu --help, or npx fireemu help <command>, for the help of the version you have installed.

Command	What it does
init	Create fireemu.toml in the current directory
up	Start the emulators and keep them running until Ctrl+C (alias: emulators:start)
exec	Start the emulators, run a command, stop them (alias: emulators:exec)
emulators:export	Export the state of a running suite to a directory
doctor	Check the installation: binary, UI, Functions runner, Node.js
capabilities	Print the capability manifest of the resolved profile as JSON

init

fireemu init - create fireemu.toml in the current directory

usage:
  fireemu init [options]

Creates fireemu.toml in the current directory and prints the command to start with it. It never overwrites an existing file unless --force is given. An existing fireemu.json must be removed before creating fireemu.toml.

options:
  --reference
        Also write fireemu.reference.toml, which fireemu does not load. With an existing fireemu.toml or fireemu.json and no --profile or --firebase-json, write only the reference. Copying a key into fireemu.toml makes it explicit and stops productionExact from switching it.
  --profile strict|emulator
        Compatibility profile. strict follows production Firebase and is recommended, including when migrating from the official emulator; emulator is only for checking alignment with the pinned official emulator and is not needed when migrating. Default: strict (asked interactively).
  --firebase-json <file>
        Reference this firebase.json from fireemu.toml, so rules, indexes, Functions and ports are read from it on every start. Default: ./firebase.json when it exists (asked interactively).
  --interactive
        Ask for the missing choices. Default: only when stdin and stdout are terminals.
  --yes, --no-interactive
        Never ask; use the defaults for what is not given.
  --force
        Replace existing output files. Default: an existing file is an error.
  -h, --help
        Print this help and exit.

up

fireemu up - start the emulators and keep them running until Ctrl-C (alias: emulators:start)

usage:
  fireemu up [options]
  fireemu emulators:start [options]

Serves the selected emulators (Firestore, Auth, Storage and App Check; Functions when a codebase is configured, and with it Eventarc and Cloud Tasks; Pub/Sub when configured; the Realtime Database when configured) plus the control API, the Emulator Hub and the UI on loopback until Ctrl-C.

options:
  --config <file>
        Configuration file: TOML (.toml) or JSON (any other extension), with schemaVersion 1, or a firebase.json. Default: ./fireemu.toml or ./fireemu.json when neither --config nor --firebase-json is given (both present is an error; remove one), else the nearest firebase.json (see --no-config-discovery), else the built-in defaults.
  --firebase-json <file>
        Read ports, rules, indexes and Functions codebases from this firebase.json. Takes precedence over one referenced by --config. Default: the one ./fireemu.toml or ./fireemu.json names, else, without either, the nearest firebase.json in the current directory or a parent.
  --no-config-discovery
        Do not search for ./fireemu.toml, ./fireemu.json or the nearest firebase.json when neither --config nor --firebase-json is given; use the built-in defaults. Also silences the warning for a discovered file that was skipped because of its owner or permissions. Default: the search is on.
  -P, --project <id|alias>
        Project ID, or an alias from the .firebaserc next to the firebase.json (else the current directory). Default: the .firebaserc default, else daemon.authProject from --config, else demo-app.
  --only <list>
        Comma-separated services to start: auth, firestore, storage, functions (or functions:<codebase>), eventarc, tasks, pubsub, database, appcheck. Default: Firestore, Auth, Storage and App Check; Functions when a codebase is configured (firebase.json or --functions), and with it Eventarc and Cloud Tasks; Pub/Sub when configured (emulators.pubsub, daemon.pubsubPort or --pubsub-port); the Realtime Database when configured (emulators.database, daemon.databasePort or --database-port).
  --firestore-port <n>
        Firestore port. Default: 8080 (0 picks a free port).
  --http-port <n>
        Auth (Identity Toolkit) port. Default: 9099 (0 picks a free port).
  --storage-port <n>
        Storage port. Default: 9199 (0 picks a free port).
  --functions-port <n>
        Functions port, used when a codebase is loaded. Default: 5001 (0 picks a free port).
  --eventarc-port <n>
        Eventarc port. Eventarc starts exactly when a Functions backend is loaded; this option only sets the port. Default: 9299.
  --tasks-port <n>
        Cloud Tasks port. Cloud Tasks starts exactly when a Functions backend is loaded; this option only sets the port. Default: 9499.
  --pubsub-port <n>
        Pub/Sub port. Without --only, giving it also starts Pub/Sub; with --only, Pub/Sub starts only when the list names pubsub. Default: 8085.
  --database-port <n>
        Realtime Database port. Without --only, giving it also starts the Realtime Database; with --only, it starts only when the list names database. Default: 9000.
  --functions <dir>
        Load exactly one Functions codebase from this directory, whatever firebase.json declares. Default: the codebases firebase.json declares.
  --ui-port <n|auto>
        UI port; auto assigns an available port, 0 disables the UI. Default: 4000 for up (the UI is skipped if that port is busy), off for exec.
  --hub-port <n|auto>
        Emulator Hub port; auto assigns an available port, 0 disables it. Default: 4400.
  --logging-port <n>
        Logging emulator port; 0 disables it. Default: 4500.
  --inspect-functions [port]
        Run the Functions runner under the Node inspector on this port (1024-65535); without a port, or with `true`, a free port. Refused when functions.runner is not node. Default: off.
  --log-verbosity quiet|silent|info|debug
        quiet and silent print errors only; info adds the banner and notices; debug also prints the resolved configuration. Case-insensitive. Default: info.
  --import <dir>
        Import an export directory (from --export-on-exit or emulators:export) at start; it must exist. Default: start empty.
  --export-on-exit [dir]
        Export all state to this directory when the emulators stop; without a directory, the --import directory. Refused for the working directory or a parent of it, and unavailable on Windows. Default: no export.
  --ready-file <file>
        Publish endpoint discovery, including a control capability, to this private file once every listener is bound, and remove it on graceful shutdown. For tooling such as fireemu/testing. Default: none.
  --owner-stdin
        Shut down when standard input is closed. For tooling such as fireemu/testing. Default: off.
  -h, --help
        Print this help and exit.

exec

fireemu exec - start the emulators, run a command, stop them (alias: emulators:exec)

usage:
  fireemu exec [options] "shell script"
  fireemu exec [options] -- <command...>
  fireemu emulators:exec [options] "shell script"
  fireemu emulators:exec [options] -- <command...>

Starts the same emulators as `up`, runs the command with the emulator host environment variables (FIRESTORE_EMULATOR_HOST, FIREBASE_AUTH_EMULATOR_HOST, and so on) once every listener is bound, stops everything when the command exits, and exits with the command's status. On Unix, a command ended by signal n gives 128 + n, and SIGINT and SIGTERM are forwarded to it.

With "shell script" (the official form) the script is run by the system shell. With `--` the command is run as exactly that program and argv, without a shell. Everything after `--` belongs to the command, including --help; a `--help` inside the script text is script text.

options:
  --config <file>
        Configuration file: TOML (.toml) or JSON (any other extension), with schemaVersion 1, or a firebase.json. Default: ./fireemu.toml or ./fireemu.json when neither --config nor --firebase-json is given (both present is an error; remove one), else the nearest firebase.json (see --no-config-discovery), else the built-in defaults.
  --firebase-json <file>
        Read ports, rules, indexes and Functions codebases from this firebase.json. Takes precedence over one referenced by --config. Default: the one ./fireemu.toml or ./fireemu.json names, else, without either, the nearest firebase.json in the current directory or a parent.
  --no-config-discovery
        Do not search for ./fireemu.toml, ./fireemu.json or the nearest firebase.json when neither --config nor --firebase-json is given; use the built-in defaults. Also silences the warning for a discovered file that was skipped because of its owner or permissions. Default: the search is on.
  -P, --project <id|alias>
        Project ID, or an alias from the .firebaserc next to the firebase.json (else the current directory). Default: the .firebaserc default, else daemon.authProject from --config, else demo-app.
  --only <list>
        Comma-separated services to start: auth, firestore, storage, functions (or functions:<codebase>), eventarc, tasks, pubsub, database, appcheck. Default: Firestore, Auth, Storage and App Check; Functions when a codebase is configured (firebase.json or --functions), and with it Eventarc and Cloud Tasks; Pub/Sub when configured (emulators.pubsub, daemon.pubsubPort or --pubsub-port); the Realtime Database when configured (emulators.database, daemon.databasePort or --database-port).
  --firestore-port <n>
        Firestore port. Default: 8080 (0 picks a free port).
  --http-port <n>
        Auth (Identity Toolkit) port. Default: 9099 (0 picks a free port).
  --storage-port <n>
        Storage port. Default: 9199 (0 picks a free port).
  --functions-port <n>
        Functions port, used when a codebase is loaded. Default: 5001 (0 picks a free port).
  --eventarc-port <n>
        Eventarc port. Eventarc starts exactly when a Functions backend is loaded; this option only sets the port. Default: 9299.
  --tasks-port <n>
        Cloud Tasks port. Cloud Tasks starts exactly when a Functions backend is loaded; this option only sets the port. Default: 9499.
  --pubsub-port <n>
        Pub/Sub port. Without --only, giving it also starts Pub/Sub; with --only, Pub/Sub starts only when the list names pubsub. Default: 8085.
  --database-port <n>
        Realtime Database port. Without --only, giving it also starts the Realtime Database; with --only, it starts only when the list names database. Default: 9000.
  --functions <dir>
        Load exactly one Functions codebase from this directory, whatever firebase.json declares. Default: the codebases firebase.json declares.
  --ui
        Start the UI while the command runs (exec does not start it otherwise, as in `firebase emulators:exec`). --ui-port overrides.
  --ui-port <n|auto>
        UI port; auto assigns an available port, 0 disables the UI. Default: 4000 for up (the UI is skipped if that port is busy), off for exec.
  --hub-port <n|auto>
        Emulator Hub port; auto assigns an available port, 0 disables it. Default: 4400.
  --logging-port <n>
        Logging emulator port; 0 disables it. Default: 4500.
  --inspect-functions [port]
        Run the Functions runner under the Node inspector on this port (1024-65535); without a port, or with `true`, a free port. Refused when functions.runner is not node. Default: off.
  --log-verbosity quiet|silent|info|debug
        quiet and silent print errors only; info adds the banner and notices; debug also prints the resolved configuration. Case-insensitive. Default: info.
  --import <dir>
        Import an export directory (from --export-on-exit or emulators:export) at start; it must exist. Default: start empty.
  --export-on-exit [dir]
        Export all state to this directory when the emulators stop; without a directory, the --import directory. Refused for the working directory or a parent of it, and unavailable on Windows. Default: no export.
  --ready-file <file>
        Publish endpoint discovery, including a control capability, to this private file once every listener is bound, and remove it on graceful shutdown. For tooling such as fireemu/testing. Default: none.
  --owner-stdin
        Shut down when standard input is closed. For tooling such as fireemu/testing. Default: off.
  -h, --help
        Print this help and exit.

emulators:export

fireemu emulators:export - export the state of a running suite to a directory

usage:
  fireemu emulators:export <dir> [options]

Asks the suite that is already running for the project (found through its Emulator Hub locator file) to write its state to <dir>, in the format --import reads. Not available on Windows.

options:
  -P, --project <id>
        Project of the running suite. Default: the .firebaserc default in the current directory, else demo-app.
  -f, --force
        Overwrite a non-empty destination. Default: refused.
  -h, --help
        Print this help and exit.

doctor

fireemu doctor - check the installation: binary, UI, Functions runner, Node.js

usage:
  fireemu doctor [--connect <control url> | --export-dir <path>]

Reports the Fireemu binary, UI, Functions runner and Node.js that this installation finds, and suggests a remedy for each problem.

options:
  --export-dir path
        Inspect an export destination and its ancestors without starting a daemon or changing files. Export checks again when it writes. Cannot be combined with --connect.
  --connect http://127.0.0.1:<port>
        Also report what a running suite says, through its control URL (the control port is printed at startup). Default: only the offline report.
  -h, --help
        Print this help and exit.

capabilities

fireemu capabilities - print the capability manifest of the resolved profile as JSON

usage:
  fireemu capabilities [options]

Prints the capability manifest for the profile the options resolve to. It accepts the same options as `up` and validates them the same way, but only --config (the profile it names) changes the result.

options:
  --config <file>
        Configuration file: TOML (.toml) or JSON (any other extension), with schemaVersion 1, or a firebase.json. Default: ./fireemu.toml or ./fireemu.json when neither --config nor --firebase-json is given (both present is an error; remove one), else the nearest firebase.json (see --no-config-discovery), else the built-in defaults.
  --firebase-json <file>
        Read ports, rules, indexes and Functions codebases from this firebase.json. Takes precedence over one referenced by --config. Default: the one ./fireemu.toml or ./fireemu.json names, else, without either, the nearest firebase.json in the current directory or a parent.
  --no-config-discovery
        Do not search for ./fireemu.toml, ./fireemu.json or the nearest firebase.json when neither --config nor --firebase-json is given; use the built-in defaults. Also silences the warning for a discovered file that was skipped because of its owner or permissions. Default: the search is on.
  -P, --project <id|alias>
        Project ID, or an alias from the .firebaserc next to the firebase.json (else the current directory). Default: the .firebaserc default, else daemon.authProject from --config, else demo-app.
  --only <list>
        Comma-separated services to start: auth, firestore, storage, functions (or functions:<codebase>), eventarc, tasks, pubsub, database, appcheck. Default: Firestore, Auth, Storage and App Check; Functions when a codebase is configured (firebase.json or --functions), and with it Eventarc and Cloud Tasks; Pub/Sub when configured (emulators.pubsub, daemon.pubsubPort or --pubsub-port); the Realtime Database when configured (emulators.database, daemon.databasePort or --database-port).
  --firestore-port <n>
        Firestore port. Default: 8080 (0 picks a free port).
  --http-port <n>
        Auth (Identity Toolkit) port. Default: 9099 (0 picks a free port).
  --storage-port <n>
        Storage port. Default: 9199 (0 picks a free port).
  --functions-port <n>
        Functions port, used when a codebase is loaded. Default: 5001 (0 picks a free port).
  --eventarc-port <n>
        Eventarc port. Eventarc starts exactly when a Functions backend is loaded; this option only sets the port. Default: 9299.
  --tasks-port <n>
        Cloud Tasks port. Cloud Tasks starts exactly when a Functions backend is loaded; this option only sets the port. Default: 9499.
  --pubsub-port <n>
        Pub/Sub port. Without --only, giving it also starts Pub/Sub; with --only, Pub/Sub starts only when the list names pubsub. Default: 8085.
  --database-port <n>
        Realtime Database port. Without --only, giving it also starts the Realtime Database; with --only, it starts only when the list names database. Default: 9000.
  --functions <dir>
        Load exactly one Functions codebase from this directory, whatever firebase.json declares. Default: the codebases firebase.json declares.
  --ui-port <n|auto>
        UI port; auto assigns an available port, 0 disables the UI. Default: 4000 for up (the UI is skipped if that port is busy), off for exec.
  --hub-port <n|auto>
        Emulator Hub port; auto assigns an available port, 0 disables it. Default: 4400.
  --logging-port <n>
        Logging emulator port; 0 disables it. Default: 4500.
  --inspect-functions [port]
        Run the Functions runner under the Node inspector on this port (1024-65535); without a port, or with `true`, a free port. Refused when functions.runner is not node. Default: off.
  --log-verbosity quiet|silent|info|debug
        quiet and silent print errors only; info adds the banner and notices; debug also prints the resolved configuration. Case-insensitive. Default: info.
  --import <dir>
        Import an export directory (from --export-on-exit or emulators:export) at start; it must exist. Default: start empty.
  --export-on-exit [dir]
        Export all state to this directory when the emulators stop; without a directory, the --import directory. Refused for the working directory or a parent of it, and unavailable on Windows. Default: no export.
  --ready-file <file>
        Publish endpoint discovery, including a control capability, to this private file once every listener is bound, and remove it on graceful shutdown. For tooling such as fireemu/testing. Default: none.
  --owner-stdin
        Shut down when standard input is closed. For tooling such as fireemu/testing. Default: off.
  -h, --help
        Print this help and exit.