49 lines
1.3 KiB
Markdown
49 lines
1.3 KiB
Markdown
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---
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tags: [node-js]
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created: Friday, April 26, 2024
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---
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# NodeJS scripts
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If we want to use NodeJS as a scripting language without going to the trouble of
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setting up an NPM-based development environment, we can use the following
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architecture.
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```js
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#!/usr/bin/env node
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const process = require("process");
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const actualScript = (firstParam, secondParam) => {
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// Do something
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};
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if (require.main === module) {
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const [, param1, param2] = process.argv;
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actualScript(param1, param2).catch(console.error);
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}
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```
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Basically we have a function that contains the main actions of the script. This
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is then invoked within `main` in the manner of a Bash or
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This obviously requires the Node binary to be in your path and the script must
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be run with executable privileges.
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If you use any module not in the Node core, you will need to have this installed
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globally for it to work. (There are
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[ways around this](https://thom4.net/2014/self-contained-node-scripts/) for Node
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scripts you publish but for personal scripts this doesn't matter.)
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## `require.main`
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This construction checks that the script is being directy invoked via the 'node'
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command in the terminal rather than called by another module.
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This is equivalent to the [following construct]() in Python:
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```py
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if __name__ == "__main__":
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```
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