.. | ||
dist | ||
client.d.ts | ||
client.js | ||
index.js | ||
LICENSE | ||
package.json | ||
README.md |
The nodemon for TypeScript
tsc-watch
starts the installed TypeScript compiler (tsc
) with --watch
parameter, with the ability to react to compilation status.
tsc-watch
was created to allow an easy dev process with TypeScript. Commonly used to restart a node server, similar to nodemon but for TypeScript.
Anything that you can do with tsc
you can do with tsc-watch
, the only difference is that tsc-watch
can react to compilation status.
Argument | Description |
---|---|
--onSuccess COMMAND |
Executes COMMAND on every successful compilation. |
--onFirstSuccess COMMAND |
Executes COMMAND on the first successful compilation. |
--onEmit COMMAND |
Executes debounced COMMAND on every emitted file, ignoring unchanged files and disregards compilation success or failure. |
--onEmitDebounceMs DELAY |
Delay by which to debounce --onEmit (default: 300). |
--onFailure COMMAND |
Executes COMMAND on every failed compilation. |
--onCompilationStarted COMMAND |
Executes COMMAND on every compilation start event (initial and incremental). |
--onCompilationComplete COMMAND |
Executes COMMAND on every successful or failed compilation. |
--maxNodeMem |
Calls node with a specific memory limit max_old_space_size , to use if your project needs more memory. |
--noColors |
By default tsc-watch adds colors the output with green on success, and in red on failure. Add this argument to prevent that. |
--noClear |
In watch mode the tsc compiler clears the screen before reportingAdd this argument to prevent that. |
--signalEmittedFiles |
Will run tsc compiler with --listEmittedFiles , but hiding TSFILE lines. Use it to enable file_emitted event, while keeping tsc stdout silent. |
--silent |
Do not print any messages on stdout. |
--compiler PATH |
The PATH will be used instead of typescript compiler.Default is typescript/bin/tsc |
Notes:
-
That all the above
COMMAND
s will be killed on process exit. (UsingSIGTERM
) -
A
COMMAND
is a single command and not multi command likescript1.sh && script2.sh
-
Any child process (
COMMAND
) will be terminated before creating a new one.
Install
npm install tsc-watch --save-dev
## for command-line usage
npm install -g typescript tsc-watch
Usage
From Command-Line
## Watching a project (with tsconfig.json)
tsc-watch --onSuccess "node ./dist/server.js"
## Beep on failure
tsc-watch --onFailure "echo Beep! Compilation Failed"
## Watching a single file
tsc-watch server.ts --outDir ./dist --onSuccess "node ./dist/server.js"
## Custom compiler
tsc-watch --onSuccess "node ./dist/server.js" --compiler my-typescript/bin/tsc
From npm script
"dev-server": "tsc-watch --noClear -p ./src/tsconfig.json --onSuccess \"node ./dist/server.js\"",
From javascript
You can see a detailed example here
The client is implemented as an instance of Node.JS
's EventEmitter
, with the following events:
started
- Emitted upon the compilation start (initial or incremental).first_success
- Emitted upon first successful compilation.subsequent_success
- Emitted upon every subsequent successful compilation.compile_errors
- Emitted upon every failing compilation.file_emitted
- Emitted upon every file transpiled if--listEmittedFiles
is used.
Once subscribed to the relevant events, start the client by running watch.start()
To kill the client, run watch.kill()
Example usage:
// Using CommonJS:
const { TscWatchClient } = require('tsc-watch/client');
// Using ES6 import:
import { TscWatchClient } from 'tsc-watch/client';
const watch = new TscWatchClient();
watch.on('started', () => {
console.log('Compilation started');
});
watch.on('first_success', () => {
console.log('First success!');
});
watch.on('success', () => {
// Your code goes here...
});
watch.on('compile_errors', () => {
// Your code goes here...
});
watch.start('--project', '.');
try {
// do something...
} catch (e) {
watch.kill(); // Fatal error, kill the compiler instance.
}
Notes:
- The (
onSuccess
)COMMAND
will not run if the compilation failed. - The (
onEmit
)COMMAND
will not run if the compilation succeeded with no changed files, unless it is the first success. - The (
onEmit
)COMMAND
will run even if the compilation failed, but emitted changed files. - The (
onEmit
)COMMAND
will not run 100 times for 100 files, due to--onEmitDebounce
- The (
onEmit
)COMMAND
is not cancelling theonSuccess
/onFirstSuccess
/onFailure
/onCompilationComplete
/onCompilationStarted
commands and vice versa. tsc-watch
is using the currently installed TypeScript compiler.tsc-watch
is not changing the compiler, just adds the new arguments, compilation is the same, and all other arguments are the same.