node-api: add napi_create_buffer_from_arraybuffer method

[mertcanaltin]

introduces a new N-API method napi_create_buffer_from_arraybuffer that allows the creation of a Buffer from an ArrayBuffer. This new method provides functionality similar to napi_create_typedarray, enabling developers to specify a byte offset and length to create a Buffer from a portion of the ArrayBuffer. This feature addresses the limitation where it was previously not possible to create a Buffer directly from an ArrayBuffer using N-API.

Closes: #54440

[nodejs-github-bot]

Review requested:

• @nodejs/node-api

[mertcanaltin]

I made make in my local environment and ran the make only-tesy command and saw that it passed the build and tests, I will check the places that give errors again.

[ronag]

I'm not sure this is actually creating a node buffer.

[ronag]

LGTM but would like another review from someone more familiar with this part of the code.

[codecov]

Codecov Report

Attention: Patch coverage is 50.00000% with 8 lines in your changes missing coverage. Please review.

Project coverage is 88.41%. Comparing base (aac8ba7) to head (6c4e386).
Report is 137 commits behind head on main.

Files with missing lines	Patch %	Lines
src/node_api.cc	50.00%	3 Missing and 5 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #54505      +/-   ##
==========================================
+ Coverage   88.24%   88.41%   +0.16%     
==========================================
  Files         651      652       +1     
  Lines      183856   186628    +2772     
  Branches    35853    36065     +212     
==========================================
+ Hits       162251   165001    +2750     
+ Misses      14896    14885      -11     
- Partials     6709     6742      +33     

Files with missing lines	Coverage Δ
src/node_api.cc	76.26% <50.00%> (-0.53%)	⬇️

... and 135 files with indirect coverage changes

[legendecas]

@ronag would you mind sharing a use case for this method? Does https://nodejs.org/api/n-api.html#napi_create_typedarray work for the use case?

We talked about this in Node-API meeting, a new node-api can not be easily changed or deprecated, a concrete use case would really help us understand the necessity to add the new API and if the API interface sufficient.

[ronag]

@ronag would you mind sharing a use case for this method? Does https://nodejs.org/api/n-api.html#napi_create_typedarray work for the use case?

We talked about this in Node-API meeting, a new node-api can not be easily changed or deprecated, a concrete use case would really help us understand the necessity to add the new API and if the API interface sufficient.

It doesn't work if I need to return node buffers in the js api. I guess I could change the prototype in js but that seems a bit ugly.

[ronag]

@nodejs/node-api

[mertcanaltin]

I set napi signature but get call to undeclared function error, I wonder if anyone has a comment on this

gyp info spawn args [ 'BUILDTYPE=Release', '-C', 'build' ]

  CC(target) Release/obj.target/test_buffer/test_buffer.o

../test_buffer.c:148:12: error: call to undeclared function 'node_api_create_buffer_from_arraybuffer'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]

  status = node_api_create_buffer_from_arraybuffer(

           ^

../test_buffer.c:148:12: note: did you mean 'napi_create_external_arraybuffer'?

/Users/mert/Library/Caches/node-gyp/20.17.0/include/node/js_native_api.h:433:1: note: 'napi_create_external_arraybuffer' declared here

napi_create_external_arraybuffer(napi_env env,

^

1 error generated.

make: *** [Release/obj.target/test_buffer/test_buffer.o] Error 1

hmm I'm getting errors on my local, but here the tests seem to have passed 🤔

[vmoroz]

hmm I'm getting errors on my local, but here the tests seem to have passed 🤔

I suspect you are running gyp for the installed Node.js instance instead of the one built on your machine. This is why it cannot find the new function that is added in your PR.

I typically build the tests on Windows with vcbuild.bat and then iterate on them inside of Visual Studio. To run them using the built Node.js instance I usually do out\Debug\node.exe test\node-api\test_buffer\test.js. I.e. the key here is to use the Node.js instance from the out folder. I guess on Mac it can be done in a similar way.

[mertcanaltin]

I suspect you are running gyp for the installed Node.js instance instead of the one built on your machine. This is why it cannot find the new function that is added in your PR.

I typically build the tests on Windows with vcbuild.bat and then iterate on them inside of Visual Studio. To run them using the built Node.js instance I usually do out\Debug\node.exe test\node-api\test_buffer\test.js. I.e. the key here is to use the Node.js instance from the out folder. I guess on Mac it can be done in a similar way.

this worked very well thank you very much

[vmoroz]

LGTM

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/62964/

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/62999/

[legendecas]

The CI is passed and we have two approvals. @gabrielschulhof would you mind taking a last review? thanks

[nodejs-github-bot]

Landed in fdf838a