feat: create a bundled build of wasm

[jeswr]

Follows up on the discussion SWI-Prolog/npm-swipl-wasm#8 to produce a swipl-bundle.js build which inlines the .wasm and .data files.

[jeswr]

Another useful build is the swipl-bundle without any data file inlined. This is because that file is not used when there is another pre-loaded image being used such as eyereasoner/eye-js#21.

Would you accept another build of this nature? It would require the change in #1088 (comment); but the result is a 2.5M bundle (as opposed to 11M with the --embed-file ${WASM_PRELOAD_DIR}@swipl flag enabled).

[jeswr]

Suggested change

	set(WASM_BUNDLE_LINK_FLAGS
	-s SINGLE_FILE
	--embed-file ${WASM_PRELOAD_DIR}@swipl)
	join_list(WASM_BUNDLE_LINK_FLAGS_STRING " " ${WASM_BUNDLE_LINK_FLAGS} " " ${WASM_SHARED_LINK_FLAGS})
	add_executable(swipl-bundle ${SWIPL_SRC})
	set_target_properties(swipl-bundle PROPERTIES
	LINK_FLAGS "${WASM_BUNDLE_LINK_FLAGS_STRING}")
	target_link_libraries(swipl-bundle libswipl)
	add_dependencies(swipl-bundle wasm_preload)
	set_property(TARGET swipl-bundle PROPERTY LINK_DEPENDS
	${POSTJS} ${PREJS})
	set(WASM_BUNDLE_EMBEDDED_LINK_FLAGS
	-s SINGLE_FILE
	--embed-file ${WASM_PRELOAD_DIR}@swipl)
	set(WASM_BUNDLE_LINK_FLAGS
	-s SINGLE_FILE)
	join_list(WASM_BUNDLE_LINK_FLAGS_STRING " " ${WASM_BUNDLE_LINK_FLAGS} " " ${WASM_SHARED_LINK_FLAGS})
	join_list(WASM_BUNDLE_EMBEDDED_LINK_FLAGS_STRING " " ${WASM_BUNDLE_EMBEDDED_LINK_FLAGS} " " ${WASM_SHARED_LINK_FLAGS})
	add_executable(swipl-bundle ${SWIPL_SRC})
	set_target_properties(swipl-bundle PROPERTIES
	LINK_FLAGS "${WASM_BUNDLE_LINK_FLAGS_STRING}")
	target_link_libraries(swipl-bundle libswipl)
	add_dependencies(swipl-bundle wasm_preload)
	set_property(TARGET swipl-bundle PROPERTY LINK_DEPENDS
	${POSTJS} ${PREJS})
	add_executable(swipl-bundle-embedded ${SWIPL_SRC})
	set_target_properties(swipl-bundle-embedded PROPERTIES
	LINK_FLAGS "${WASM_BUNDLE_EMBEDDED_LINK_FLAGS_STRING}")
	target_link_libraries(swipl-bundle-embedded libswipl)
	add_dependencies(swipl-bundle-embedded wasm_preload)
	set_property(TARGET swipl-bundle-embedded PROPERTY LINK_DEPENDS
	${POSTJS} ${PREJS})

[jeswr]

@JanWielemaker - This is ready for review

[JanWielemaker]

This is ready for review

Hope to take care of this shortly. I've a bit of a backlog on issues though 😢

[JanWielemaker]

The bundle builds fine, but trying to use it in shell.html results in

TypeError: Module.preRun is undefined

What does this change to how it is supposed to be used?

[jeswr]

preRun is used to perform operations before initializing SWIPL (for instance here https://github.com/eyereasoner/eye-js/blob/0cc5e11f44a042f322c6e77e3370d8b6b5d30011/scripts/generate-pvm.ts#L36-L39 it loads eye.pl before swipl -q -f eye.pl is run).

It should be able to be left undefined and in those cases just do nothing. I'm unsure why this is a new error - I don't think it would be caused by the new configuration file. In particular I did not get any errors of the sorts when using the output of this build file on commit b089616 (i.e. the commit that npm-swipl-wasm is using in the DockerFile). Have you made any changes to any other code since then that may be the culprit?

[jeswr]

I tried having a quick look at this diff but could not identify anything that might be the cause on first parse.

[jeswr]

I've tried (unsucessfully) to reproduce this error on this branch of npm-swipl-wasm. To test simply clone the branch and then run

yarn install
yarn run build
yarn run serve

For me the website appears to run without problem

---

In addition, I've tested these changes on the latest version of swipl-devel in the same branch. The npm-swipl-wasm tests run fine after the changes in #1102 are made.

However if I add a new test

it(`[${name}] ` + "should be able to preload files and generate images", async () => {
        const eye = await eyePlString();

        const Module = await SWIPL({ 
          arguments: ['-q', '-f', 'eye.pl'],
          preRun: (Module) => Module.FS.writeFile('eye.pl', eye) });
        
        queryOnce(Module, 'main', ['--image', 'eye.pvm']);

        assert.strictEqual(Module.FS.readFile('eye.pvm').length > 500, true);
      });

then it fails with

  1) SWI-Prolog WebAssembly on Node.js
       [node] should be able to preload files and generate images:
     TypeError: Module.preRun.push is not a function
      at loadPackage (dist/swipl/swipl.js:9:6290)
      at /home/jesse/Documents/github/npm-swipl-wasm/dist/swipl/swipl.js:9:6308
      at /home/jesse/Documents/github/npm-swipl-wasm/dist/swipl/swipl.js:9:30567
      at module.exports (dist/swipl-node.js:8:10)
      at Context.<anonymous> (tests/node.js:83:30)
      at process.processTicksAndRejections (node:internal/process/task_queues:95:5)

  2) SWI-Prolog WebAssembly on Node.js
       [web] should be able to preload files and generate images:
     TypeError: Module.preRun.push is not a function
      at loadPackage (dist/swipl/swipl-web.js:9:6290)
      at /home/jesse/Documents/github/npm-swipl-wasm/dist/swipl/swipl-web.js:9:6308
      at /home/jesse/Documents/github/npm-swipl-wasm/dist/swipl/swipl-web.js:9:30567
      at Context.<anonymous> (tests/node.js:83:30)
      at process.processTicksAndRejections (node:internal/process/task_queues:95:5)

but this test runs fine on the bundled build.

NOTE These errors come from

swipl-devel/src/wasm/pre.js

Lines 128 to 130 in 4a83822

	if ( Module.on_output )
	{ Module.preRun.push(bind_std_streams);
	}

NOTE: These errors also occur with the original CMAKE file on commit b089616

NOTE: #1103 Resolves this error