[TS] Schema Types Generation

[Convly]

What does it do?

Add a command to the CLI to automatically generate typings based on the application schemas, then load them in the Strapi.Schemas global interface so that they can be used in the whole application.

Why is it needed?

Develop experience improvement to automatically regenerate typings for local schemas (components and content types) and benefit from better typings everywhere in the application.

It'll also be necessary to have this tool when we'll start writing new types for the Strapi APIs, so that the types inference can be as good as possible.

How to test it?

1. Clone the strapi repository
2. Navigate to the examples/getstarted application
3. Run the following command: yarn strapi ts:generate-types
   • --verbose to trigger the verbose mode
   • --silent or -s to trigger the silent mode
   • -o or --out-dir to specify the out directory in which the file will be created
   • -f or --file to specific the filename that will contain the types declarations
4. A file named schemas.d.ts should have been created
5. Open this file
6. It should contain TypeScript types definition for every content type of the application (defined by the user, plugins or Strapi)
7. It should also contain a declare global expression that extends the Strapi.Schemas interface with all the generated typings

[codecov]

Codecov Report

Merging #13460 (704cdd8) into features/typescript (975d5bf) will decrease coverage by 2.10%.
The diff coverage is 79.06%.

@@                   Coverage Diff                   @@
##           features/typescript   #13460      +/-   ##
=======================================================
- Coverage                56.69%   54.59%   -2.11%     
=======================================================
  Files                      958     1224     +266     
  Lines                    21697    31089    +9392     
  Branches                  3562     5645    +2083     
=======================================================
+ Hits                     12302    16972    +4670     
- Misses                    8395    12289    +3894     
- Partials                  1000     1828     +828     

Flag	Coverage Δ
front	56.69% <ø> (ø)
unit	49.72% <79.06%> (?)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...kages/utils/typescript/lib/utils/resolve-outdir.js	62.50% <ø> (ø)
...s/utils/typescript/lib/generators/schemas/index.js	31.14% <31.14%> (ø)
.../utils/typescript/lib/generators/schemas/schema.js	40.00% <40.00%> (ø)
...s/utils/typescript/lib/generators/schemas/utils.js	97.87% <97.87%> (ø)
packages/utils/typescript/lib/generators/index.js	100.00% <100.00%> (ø)
...ls/typescript/lib/generators/schemas/attributes.js	100.00% <100.00%> (ø)
.../utils/typescript/lib/generators/schemas/global.js	100.00% <100.00%> (ø)
...utils/typescript/lib/generators/schemas/imports.js	100.00% <100.00%> (ø)
packages/utils/typescript/lib/index.js	100.00% <100.00%> (ø)
...itPage/components/GlobalActions/utils/constants.js
... and 262 more

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[alexandrebodin]

A few global comments before digging the code:

• Can you move this logic to the typescript utils so we just call them from the command ?
• Why not use typescript to build an ast and dump it to a file ?
  it would avoid having to do all those string manipulations and would be easier to test & safer :)

[Convly]

A few global comments before digging the code:

• Can you move this logic to the typescript utils so we just call them from the command ?
• Why not use typescript to build an ast and dump it to a file ?
  it would avoid having to do all those string manipulations and would be easier to test & safer :)

Nice insights, it's been implemented in 6c9b500

[strapi-bot]

This pull request has been mentioned on Strapi Community Forum. There might be relevant details there:

https://forum.strapi.io/t/typescript-support-has-been-added-to-4-3-0-beta-1/19517/2

[Convly]

• You will have to update the strapi package versions to be all the same there are still some 4.2.0 in there.

I believe the only package that was still in 4.2.0 was the dependency to @strapi/strapi that have been removed.

• Missing tests

Yep, indeed.

• I didn't see a lot of error handling, do you think we should do something about it?

What kind of errors do you see happening? Since we're getting the list of content types directly from a fully-loaded Strapi instance, I assumed any schema misconfiguration would be handled by Strapi validation steps. At first, I had a status column in the summary table as well as warning logs for things failings to build but I never encountered such scenarios and it ended up polluting the table output 🤷

• If the command is successful it would be good to a least log a few infos

I assumed that the verbose command was here to do that. I imagined that sometimes when piping commands or using it in CI or other tools, you might want to silence completely the command.

[strapi-bot]

This pull request has been mentioned on Strapi Community Forum. There might be relevant details there:

https://forum.strapi.io/t/strapi-second-beta-release-for-v-4-3-0/20170/1

[strapi-bot]

This pull request has been mentioned on Strapi Community Forum. There might be relevant details there:

https://forum.strapi.io/t/typescript-support-has-been-added-to-4-3-0-beta-1/19517/5

[SalahAdDin]

Is there any ETA for this project?

[Convly]

Is there any ETA for this project?

This feature will be released along with the TypeScript support feature whose ETA is the end of July.

In the meantime, you can test it using 4.3.0-beta.2 (and above) version

[alexandrebodin]

• You will have to update the strapi package versions to be all the same there are still some 4.2.0 in there.

I believe the only package that was still in 4.2.0 was the dependency to @strapi/strapi that have been removed.

• Missing tests

Yep, indeed.

• I didn't see a lot of error handling, do you think we should do something about it?

What kind of errors do you see happening? Since we're getting the list of content types directly from a fully-loaded Strapi instance, I assumed any schema misconfiguration would be handled by Strapi validation steps. At first, I had a status column in the summary table as well as warning logs for things failings to build but I never encountered such scenarios and it ended up polluting the table output 🤷

I was more referring to an error in the generation (a usecase we missed for ex) that would break and just display a code error to the user. Would have been nice to wrap som of the generators with try catch to display "We could not generate type because of an unknown errors, please report it to ..."

• If the command is successful it would be good to a least log a few infos

I assumed that the verbose command was here to do that. I imagined that sometimes when piping commands or using it in CI or other tools, you might want to silence completely the command.

We might want to go the other way around and have a -s silent option but display a minimum of info for the user to know what happened

[alexandrebodin]

I tested the Date thing and I'm noticing a diff we might want to address.

If I set default: "date-string"

The attribute will be DefaultAttr<"date-string">
But if I put a date obj it will be DefaultAttr

I'm wondering if we should have DefaultAttr In the other case 🤔 that seems a bit inconsistent don't you think ?

[Convly]

One thing we could do is to extract the actual date value from the date instance and convert it to a string literal. But by doing this, we would lose the fact that we need an actual date instance. Another possible solution to keep consistency is to willingly use "Date" instead of the actual date string for default date-string values?
I personally don't have preferences 🤷