It restarts target node process when any of required files changes (as standard
node-dev) but shares Typescript compilation process between restarts. This significantly increases speed of restarting comparing to
node-dev -r ts-node/register ...,
nodemon -x ts-node ... variations because there is no need to instantiate
ts-node compilation each time.
yarn add ts-node-dev --dev
npm i ts-node-dev --save-dev
ts-node dependency version is not fixed, so it will install the latest version by default.
ts-node-dev [node-dev|ts-node flags] [ts-node-dev flags] [node cli flags] [--] [script] [script arguments]
ts-node-dev --respawn --transpileOnly server.ts
There is also short alias
tsnd for running
tsnd --respawn server.ts
Also there are additional options specific to
--prefer-ts(default: false) - for each
.jsfile (that is not in
node_modules) will try to check if corresponding
.tsversion exists and require it.
--ignore-watch(default: ) - files/folders to be ignored by
node-dev. But also this behaviour enhanced: it will also make up
new RegExpof passed ignore string and check absolute paths of required files for match. So, to ignore everything in
node_modules, just pass
--debug- some additional debug output.
--intervalPolling interval (ms)
--debounceDebounce file change events (ms, non-polling mode)
Caveats and points of notice:
Especially for large code bases always consider running with
--transpile-onlyflag which is normal for dev workflow and will speed up things greatly. Note, that
ts-node-devwill not put watch handlers on TS files that contain only types/interfaces (used only for type checking) - this is current limitation by design.
--ignore-watchwill NOT affect files ignored by TS compilation. Use
TS_NODE_IGNOREenv variable) to pass RegExp strings for filtering files that should not be compiled, by default
Unknown flags (
nodecli flags are considered to be so) are treated like string value flags by default. The right solution to avoid ambiguity is to separate script name from option flags with
--, for example:
ts-node-dev --inspect -- my-script.ts
The good thing is that
tsconfig.jsonfile, and will reinitialize compilation on its change, but you have to restart the process manually when you update used version of
typescriptor make any other changes that may effect compilation results.
In some rare cases
ts-node-devmay fail to terminate an application by sending
SIGTERMsignal, this maybe be caused by the app having running heavy child process or something. But the app should get the signal anyway and it can be explicitly processed there:
process.on('SIGTERM', () => process.exit()).