Add --code-esm support

[willfarrell]

As of ajv@8.9.0, compiling to esm is now supported. This PR allows that functionality to be accessed.

[epoberezkin]

Thank you. It all fails because of some typescript change - the same happened in other places, the code needs to be updated to compile…

[willfarrell]

Note the inclusion of "useUnknownInCatchVariables": false. I tried the other patterns suggested from [1], but they still errored when using err.code (Property 'code' does not exist on type 'Error'.)

[1] https://stackoverflow.com/questions/60151181/object-is-of-type-unknown-typescript-generics

[bitjson]

PR reviewed and tested 👍 (I didn't realize this PR was already open when I sent #203).

@epoberezkin is there anything else that needs to happen before this can be merged? Thanks!

[bitjson]

@epoberezkin could this PR be merged? (Or maybe @jessedc?) It looks like other teams are also having to work around this issue where ajv-cli is missing the esm option from ajv. Or maybe is there some other way you'd prefer that the option be supported by ajv-cli?

[trevorr]

I would like to second the request for merging this. It's not easily usable directly from the fork repo.

Update: In case it helps anyone else, I forked the fork to swap prepublish with prepare, which allows use directly from the source repo: github:trevorr/ajv-cli#code-esm-prepare.

[Creskendoll]

Hey there @epoberezkin can you merge this PR, please? I had to use patch-package to get around this issue.

My diff file ajv-cli+5.0.0.patch

diff --git a/node_modules/ajv-cli/dist/commands/options.js b/node_modules/ajv-cli/dist/commands/options.js
index 23493ad..5d8c8c7 100644
--- a/node_modules/ajv-cli/dist/commands/options.js
+++ b/node_modules/ajv-cli/dist/commands/options.js
@@ -26,6 +26,7 @@ const ajvOptions = {
     multipleOfPrecision: boolOrNat,
     messages: { type: "boolean" },
     [`${CODE}es5`]: { type: "boolean" },
+    [`${CODE}esm`]: { type: "boolean" },
     [`${CODE}lines`]: { type: "boolean" },
     [`${CODE}optimize`]: boolOrNat,
     [`${CODE}formats`]: { type: "string" },

[jonyw4]

Any news on this?

[Creskendoll]

If you're having this issue, I recommend you to either use patch-package as I described above, or do a similar thing without using the cli:

import standaloneCode from 'ajv/dist/standalone/index.js'
import glob from 'glob'
import Ajv from 'ajv'

// Read the .json schemas
const definitions = glob('validations/**/*.json', { sync: true })
const files = await Promise.all(definitions.map(async (f) => JSON.parse((await readFile(f)).toString())))

// Use Ajv with esm set to true 
const ajv = new Ajv({
  schemas: files,
  code: {
    source: true,
    esm: true,
  },
})

// Compile and save the code
writeFileSync('out.js', standaloneCode(ajv))

[sondreb]

Sorry for just 👍🏼 bumping this PR, but what is the holdback for getting the merge done? ESM is getting more and more popular and having to copy and run some code is not optimal solution. Thanks!

[yelper]

Thread bump; this simple change would enable pipelines to generate ESM schema instead of baking generation code into the runtime. It would unlock massive perf gains for us!

[MarcDOLF]

Is there anything preventing the merge of this PR?

[dRoskar]

What's the hold up?

[MatthiasKunnen]

I believe the PR has escaped @epoberezkin's attention since this CLI option is already documented at https://ajv.js.org/standalone.html#two-step-process

... or pass the --code-esm (CLI) flag if you want ESM exported code.

but apparently was forgotten to be added.

Perhaps @jessedc can be of help here?

[jimkang]

It would be great to get this merged for those of us trying to pre-compile validators.

[damienflament]

@epoberezkin Anything new about merging this PR ? Thanks.