Node.js in Rust: How to do it and what to expect from it

The main goal of this talk is to show that it is possible to embed Node.js runtime in your Rust project and to explain why it can be beneficial.I will guide you through all the crucial steps of embedding Node.js. We will look at the official Node.js C++ embedder API and what we can do with Rust’s FFI despite its lack of C++ support. Much of this is the result of the embedding experiments I did while helping build Orogene - a package manager for Node.js-compatible projects that is written in Rust.

Transcript

1. Node.js in Rust:
   how to do it and what to
   expect from it
   Kirill Vasiltcov @virtualkirill
   

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2. in
   

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3. Why?
   

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4. in
   

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5. in
   

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6. Why
   Node.js?
   

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7. Node.js gives us
    Standard library (networking,
   file system access and so on)
    Module resolution
   and more!
   

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8. Why even bother?
   

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9. Illustration by Icons 8 from Ouch!
   (https://icons8.com/illustrations/)
   Package managers
   benefit from Node.js APIs
   

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11. use node_modules
    

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12. use node_modules
    

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14. node_modules
    

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15. Many tools rely on Node.js APIs like require()
    require() relies on…node_modules!
    

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16. Breaking
    node_modules
    breaks important
    tools
    

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17. Breaking
    node_modules
    breaks important
    tools
    

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18. Illustration by Icons 8 from Ouch!
    (https://icons8.com/illustrations/)
    Can we do better?
    

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19. require()
    fs
    

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20. require()
    fs
    

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21. require()
    fs
    Content-
    addressable
    cache?
    

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22. Why Rust?
    

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25. * Not in active development
    

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26. Medium-sized project
    installation
    memory usage
    ~300MB → ~30MB
    

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27. git push CI
    

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28. git push CI
    npm install tons-of-packages
    💰
    RAM
    CPU
    💰
    

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29. Embedding Node.js
    in orogene
    

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30. • Run JavaScript without "shelling out“
    • Shim module loading (and resolution)
    logic
    

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31. • Run JavaScript without "shelling out“
    • Shim module loading (and resolution)
    logic
    🤔
    🤔
    Content-
    addressable
    cache?
    

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34. Node.js has an embedder API
    

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35. Node.js has an embedder API
    ...but in C++
    

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36. FFI
    Foreign
    Function
    Interface
    

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37. FFI
    

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38. FFI
    Only for C!
    

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39. Fortunately,
    • Node.js can be compiled as a library
    • Node.js embedder API example has an extremely
    simple call signature
    • It is easy to export C functions from C++
    

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40. for rustc
    Building Node.js
    

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42. Simple call signature
    = Easy C wrapper
    

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43. Inside C++ code
    

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44. Inside Rust code
    

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45. Inside Rust code
    C-style string
    

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46. Rust build.rs script
    

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47. Rust build.rs script
    libnode.so.83
    

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48. Use the C wrapper from Rust
    

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49. Use the C wrapper from Rust
    

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54. and type checker…?
    

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55. https://github.com/jlkiri/nodeinrust
    

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56. Special Thanks
     Kat Marchán
     Felipe Seré
     Anna Henningsen
    and many others!
    

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57. Thank you for watching!
    

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