feat: add new method on Request class

[shinspiegel]

This is a starting point for the discussion to this method.

In this way even if the JSON information is broken or it is a invalid will return null. What do you think?

I can reduce the code the code to a single line or anything like that, but I think it's cleaner to see the intend in this way.

What I can to to improve it?

[ije]

hey @shinspiegel , i'm thinking maybe it should be decodeBody or parseBody, so we can decode the body for different content types, like form-data.

interface FormDataBody {
  get(key:string): string
  getFile(key:string): FormFile
}

interface FormFile {
  filename: string
  contentType: string
  content: Uint8Array
}

interface Request {
  ...
  decodeBody(type: 'text'): Promise<string>
  decodeBody(type: 'json'): Promise<any>
  decodeBody(type: 'form-data'): Promise<FormDataBody>
}

what do you think?

[ije]

or useBody?

[shadowtime2000]

@ije I think it would be best to only use the use- prefix for React hooks to make it easier for people to distinguish functions and hooks.

[ije]

@shadowtime2000 yes you are right!

[shinspiegel]

Hi,

I was trying to overload the method, but the intellisense keeps getting a error.

This is the right way of doing this in typescript?

async decodeBody(type: "text" | "json" | "form-data"): Promise<string | any | FormDataBody> {
...
}

Or this is the right way?

async decodeBody(type: "text"): Promise<string>
async decodeBody(type: "json"): Promise<any>
async decodeBody(type: "form-data"): Promise<FormDataBody> {
...
}

Or there is other way of doing?
I did try to find the right way in the docs but I totally lost my way on this subject in TS docs.

I was reading the Deno.Land docs to parse the form data, but I didn't find how to properly use it. I'll keep digging tomorrow.

Ps.: decodeBody is a totally better name than jsonBody 😄

[ije]

@shinspiegel well done! thank you!

• to overload the method you can do like below code:

  class Request {
      ...
      decodeBody(type: 'text'): Promise<string>
      decodeBody(type: 'json'): Promise<any>
      decodeBody(type: 'form-data'): Promise<FormDataBody>
      async decodeBody(type: string): Promise<any> {
          // decode
      }
      ...
  }

• to parse multipart/form-data body please ref https://deno.land/x/oak@v6.3.2/multipart.ts

[shinspiegel]

Hi, sorry for late response (couple of busy days)

I did try to use the TS the way show below, and for some reason the Deno compiler just doesn't get it. I'm doing something wrong? (I'm new to TS, trying to catch up)

class Request {
    ...
    decodeBody(type: 'text'): Promise<string>
    decodeBody(type: 'json'): Promise<any>
    decodeBody(type: 'form-data'): Promise<FormDataBody>
    async decodeBody(type: string): Promise<any> {
        // decode
    }
    ...
}

The VSCode still gives me error on this one.

Can I use the code from other source like multipart/form-data body please ref deno.land/x/oak@v6.3.2/multipart.ts?

Or should I create a complete separated file with the complete (and a little bit changed) version of theirs?

[ije]

hi @shinspiegel thanks for your great work, it's ok with oak, maybe we can implement the multipart module in the future.

[ije]

LGTM

[ije]

here should be:

    decodeBody(type: 'text'): Promise<string>
    decodeBody(type: 'json'): Promise<any>
    decodeBody(type: 'form-data'): Promise< FormDataBody >
    async decodeBody(type: string): Promise<any> {
       if (type === "text") {
          ...
       }
    }

[shinspiegel]

Ok, now the Deno compiler and the VSCode intellisense aren't angry with me 😄

[shinspiegel]

I guess it's done...
Or should I change something?

[ije]

@shinspiegel it looks amazing, thanks

[alfredosalzillo]

decodeBody(type: 'json'): Promise<any> could be

decodeBody<T = any>(type: 'json'): Promise<T>

so no need for a cast to have the right type.

[alfredosalzillo]

@shinspiegel

In this way even if the JSON information is broken or it is a invalid will return null. What do you think?

I think if the JSON is invalid should not return null but throw an exception because it's to the developer using it handle this case.

[shinspiegel]

@alfredosalzillo

I think if the JSON is invalid should not return null but throw an exception because it's to the developer using it handle this case.

A unhandle exception would broke the application, stopping from working, right?

@alfredosalzillo

decodeBody<T = any>(type: 'json'): Promise<T>

This looks like a great idea!
I'll make it soon!

[alfredosalzillo]

A unhandle exception would broke the application, stopping from working, right?

Yes, but how I know if the response body is null or if it's an invalid JSON, without exception?
For example, the json in the response object of the fetch doesn't handle the exception.

[ije]

@shinspiegel sorry, you can not validate the types by

decodeBody<T = any>(type: 'json'): Promise<T>

you should create your own validate function:

type User = {
  id: number
  name: string
}

function isUser(v: any): v is User {
  return typeof v === 'object' && v !== null && typeof v.id === 'number' && typeof v.name === 'string' 
}

const body = await req.decodeBody('json')
if (isUser(body)) {
  // body type is User
} else {
  req.status(400).send("bad request")
}

[shinspiegel]

@ije what about the thowing exception on the JSON parse, should I improve it?
In this case I should make another pull request with this change?

[ije]

@shinspiegel i think we should remove the try catch, let user catch errors themselves:

try {
  const data = await req.decodeBody('json')
  req.status(200).send("hello " + data.name)
} catch(e) {
  req.status(400).send("bad request")
}

[ije]

@shinspiegel do you have time to implement a multipart mod as alephjs part? i saw the oak/multipart imported some deps alephjs never used. or i can add it later, thanks for your great work!

[shinspiegel]

@ije
@shinspiegel do you have time to implement a multipart mod as alephjs part? i saw the oak/multipart imported some deps alephjs never used. or i can add it later, thanks for your great work!

Sure I'll make a new branch and start my next free night. That will be a excellent opportunity to learn a thing or two.

@ije
@shinspiegel i think we should remove the try catch, let user catch errors themselves:

try {
  const data = await req.decodeBody('json')
  req.status(200).send("hello " + data.name)
} catch(e) {
  req.status(400).send("bad request")
}

I'll change the try/catch block on the same branch/issue.