Ts-node: Susgestion: Add --watch option

[k8w]

Add --watch option

for restarting the process when code changed

[blakeembrey]

No, you should probably be using an actual process manager instead.

[blakeembrey]

Try something like https://github.com/Qard/onchange.

[wclr]

@twoeo you may try to use this version of node-dev + ts-node

[niedzielski]

Thank you for providing this tool! Just curious (and I think the answer is that this functionality is not supported and there are no plans for it) but tsc provides a watch option. When I enabled it via ts-node -O '{ "watch": true }' (or directly in the config file), I was hoping to see the same file monitoring behavior but it seems to have no effect. Is this intentional?

[blakeembrey]

@niedzielski What exactly would a "watch" mode do in your opinion?

[niedzielski]

@blakeembrey, I was thinking watch would allow tsc to recompile files automatically as per usual and ts-node would wait for compilation completion and automatically shutdown and restart the server for each change. For example, an alternative would be: nodemon -e ts -x ts-node. I realize I'm probably naively missing a lot of detail but I don't think the need is uncommon.

[blakeembrey]

Use nodemon or onchange (mentioned above). This isn't really something that should be supported by ts-node as it'll just create more issues (why does it restart the server instead of reloading a single file, etc). I don't really want to deal with those. It would also complicate the project with the need to watch files, when there's better programs out there already (nodemon, pm2, onchange, etc).

[niedzielski]

@blakeembrey, thanks for the follow-up and reasoning!

[blakeembrey]

No problem. I honestly did consider having a flag to enable the behaviour, but unfortunately there's runtime and code overhead (watching the files in the project for changes). If it provided a performance benefit (e.g. possible to reload a single file efficiently in node.js) without significant overhead, I'd be willing to revisit the topic.

[wclr]

@niedzielski you may just try ts-node-dev this is modified version of node-dev (which is the fastest node watcher/reloader) that uses ts-node for compilation and it doesn't reinitialize whole compilation process on each change like nodemon -e ts -x ts-node

[blakeembrey]

@whitecolor You should probably get that in the README somewhere 😄

[niedzielski]

@whitecolor thanks!

[windware-ono]

Good thing about node-dev (ts-node-dev) is that you don't have to specify any files to monitor as any files that were 'require'ed would be automatically monitored but if some are 'require'ed at a later point, it won't be picked up though. You could require them at the start explicitly (assuming they don't do any destructive operations) to just preload them.