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kian

Kkian What's your code?

Socal

S

Socal•1/12/24, 12:18 AM

export default {
    async fetch(request: Request, env: Env, ctx: ExecutionContext): Promise<Response> {
        const results: string[] = [];


        const options = {
            header: true,
            dynamicTyping: true,
        };


        const req = await request.formData();
        console.log(req);
        const result = papa.parse(req.get('blob'), options);
        console.log(result);

    
        return new Response('Hello World!');
    },
};

export default {
    async fetch(request: Request, env: Env, ctx: ExecutionContext): Promise<Response> {
        const results: string[] = [];


        const options = {
            header: true,
            dynamicTyping: true,
        };


        const req = await request.formData();
        console.log(req);
        const result = papa.parse(req.get('blob'), options);
        console.log(result);

    
        return new Response('Hello World!');
    },
};

kian

Kkian What's your code?

Socal

S

Socal•1/12/24, 12:19 AM

console.log(req) gives

FormData(1) {
  'blob' => File {
    lastModified: 1705018748508,
    name: 'csv_filename.csv',
    type: 'text/csv',
    size: 2007
  }
}

FormData(1) {
  'blob' => File {
    lastModified: 1705018748508,
    name: 'csv_filename.csv',
    type: 'text/csv',
    size: 2007
  }
}

kian

K

kianOP•1/12/24, 12:20 AM

What makes you think there isn't a get() method though? Does the

papa.parse()

papa.parse()

call fail?

kian

Kkian What makes you think there isn't a get() method though? Does the `papa.parse()` ...

Socal

S

Socal•1/12/24, 12:23 AM

ok, i did double check. it does have a get method that returns

File {
  lastModified: 1705018963031,
  name: 'csv_filename.csv',
  type: 'text/csv',
  size: 2007
}

File {
  lastModified: 1705018963031,
  name: 'csv_filename.csv',
  type: 'text/csv',
  size: 2007
}

. How do I access the file?

Socal

S

Socal•1/12/24, 12:24 AM

or what do i need to be sending into papaparse

kian

K

kianOP•1/12/24, 12:25 AM

It's a

File

File

, which extends

Blob

Blob

, so there's methods like

arrayBuffer()

arrayBuffer()

,

stream()

stream()

and

text()

text()

kian

K

kianOP•1/12/24, 12:26 AM

https://developer.mozilla.org/en-US/docs/Web/API/Blob

kian

Kkian It's a `File`, which extends `Blob`, so there's methods like `arrayBuffer()`, `s...

Socal

S

Socal•1/12/24, 12:58 AM

thank you. I got it working. Apparently i needed to use text() text and then pass it into papaparse as papaparse tries to use FileReaderSync otherwise

Ranjan Mangla

R

Ranjan Mangla•1/12/24, 9:54 AM

How to setup. Cors in workers?

Ranjan Mangla

R

Ranjan Mangla•1/12/24, 9:55 AM

On doing a put request to my worker from react front end (store data in R2), I am getting cors error,

Ranjan Mangla

R

Ranjan Mangla•1/12/24, 9:55 AM

Tried setting up. Cors headers, still not working

Ranjan Mangla

RRanjan Mangla Tried setting up. Cors headers, still not working

Hello, I’m Allie!

H

Hello, I’m Allie!•1/12/24, 9:55 AM

Can you give us a code example to show what you are doing right now?

Ranjan Mangla

R

Ranjan Mangla•1/12/24, 9:59 AM

this is what i am doing:

export default {
  async fetch(request, env, ctx) {

    if (request.method == 'GET') {
        return new Response('Hello');
    }
 
    if (request.method === 'PUT') {
        // Note that you could require authentication for all requests
        // by moving this code to the top of the fetch function.
        const auth = request.headers.get('Authorization');
        const expectedAuth = `Bearer ${env.AUTH_SECRET}`;
  
        if (!auth || auth !== expectedAuth) {
          return new Response('Unauthorized', { status: 401 });
        }

        const corsHeaders = {
            "Access-Control-Allow-Origin": "*",
            "Access-Control-Allow-Methods": "GET,HEAD,POST,OPTIONS",
            "Access-Control-Max-Age": "86400",
        };
        
        const url = new URL(request.url);
        const key = url.pathname.slice(1);
        await env.MY_BUCKET.put(key, request.body);
        const data = `Object ${key} uploaded successfully!`;
        // return new Response(`Object ${key} uploaded successfully!`);
        return new Response(JSON.stringify(data), {
            headers: {
                ...corsHeaders,
                'Content-Type': 'application/json;charset=UTF-8'
            }
        })
    }
   },
};

export default {
  async fetch(request, env, ctx) {

    if (request.method == 'GET') {
        return new Response('Hello');
    }
 
    if (request.method === 'PUT') {
        // Note that you could require authentication for all requests
        // by moving this code to the top of the fetch function.
        const auth = request.headers.get('Authorization');
        const expectedAuth = `Bearer ${env.AUTH_SECRET}`;
  
        if (!auth || auth !== expectedAuth) {
          return new Response('Unauthorized', { status: 401 });
        }

        const corsHeaders = {
            "Access-Control-Allow-Origin": "*",
            "Access-Control-Allow-Methods": "GET,HEAD,POST,OPTIONS",
            "Access-Control-Max-Age": "86400",
        };
        
        const url = new URL(request.url);
        const key = url.pathname.slice(1);
        await env.MY_BUCKET.put(key, request.body);
        const data = `Object ${key} uploaded successfully!`;
        // return new Response(`Object ${key} uploaded successfully!`);
        return new Response(JSON.stringify(data), {
            headers: {
                ...corsHeaders,
                'Content-Type': 'application/json;charset=UTF-8'
            }
        })
    }
   },
};

Ranjan Mangla

RRanjan Mangla this is what i am doing: ``` export default { async fetch(request, env, ctx) {...

Hello, I’m Allie!

H

Hello, I’m Allie!•1/12/24, 10:01 AM

Oh, I see. Your browser is probably sending a

OPTIONS

OPTIONS

request to check for CORS headers, which you aren't handling, so it errors. Try adding an

if

if

statement for

OPTIONS

OPTIONS

requests that

return new Response(null, {
  headers: {
    "Access-Control-Allow-Origin": "*",
    "Access-Control-Allow-Methods": "GET,HEAD,POST,OPTIONS",
    "Access-Control-Max-Age": "86400",
  }
});

return new Response(null, {
  headers: {
    "Access-Control-Allow-Origin": "*",
    "Access-Control-Allow-Methods": "GET,HEAD,POST,OPTIONS",
    "Access-Control-Max-Age": "86400",
  }
});

and then see if it works.

Original message was deleted

Hello, I’m Allie!

H

Hello, I’m Allie!•1/12/24, 10:05 AM

https://tenor.com/view/wow-gif-20411229

Tenor

Original message was deleted

Hello, I’m Allie!

H

Hello, I’m Allie!•1/12/24, 10:06 AM

Thanks for the save!

Ranjan Mangla

R

Ranjan Mangla•1/12/24, 10:12 AM

still getting it , here is my code:

/**
 * Welcome to Cloudflare Workers! This is your first worker.
 *
 * - Run `npm run dev` in your terminal to start a development server
 * - Open a browser tab at http://localhost:8787/ to see your worker in action
 * - Run `npm run deploy` to publish your worker
 *
 * Learn more at https://developers.cloudflare.com/workers/
 */


export default {
  async fetch(request, env, ctx) {


    if (request.method === 'OPTIONS') {
        return new Response(null, {
          headers: {
            "Access-Control-Allow-Origin": "*",
            "Access-Control-Allow-Methods": "GET,HEAD,POST,OPTIONS",
            "Access-Control-Max-Age": "86400",
          }
        });
    }

    if (request.method == 'GET') {
        return new Response('Hello');
    }
 
    if (request.method === 'PUT') {
        // Note that you could require authentication for all requests
        // by moving this code to the top of the fetch function.
        const auth = request.headers.get('Authorization');
        const expectedAuth = `Bearer ${env.AUTH_SECRET}`;
  
        if (!auth || auth !== expectedAuth) {
          return new Response('Unauthorized', { status: 401 });
        }

        const corsHeaders = {
            "Access-Control-Allow-Origin": "*",
            "Access-Control-Allow-Methods": "GET,HEAD,POST,OPTIONS",
            "Access-Control-Max-Age": "86400",
        };
        
        const url = new URL(request.url);
        const key = url.pathname.slice(1);
        await env.MY_BUCKET.put(key, request.body);
        const data = `Object ${key} uploaded successfully!`;
        // return new Response(`Object ${key} uploaded successfully!`);
        return new Response(JSON.stringify(data), {
            headers: {
                ...corsHeaders,
                'Content-Type': 'application/json;charset=UTF-8'
            }
        })
    }
   },
};

/**
 * Welcome to Cloudflare Workers! This is your first worker.
 *
 * - Run `npm run dev` in your terminal to start a development server
 * - Open a browser tab at http://localhost:8787/ to see your worker in action
 * - Run `npm run deploy` to publish your worker
 *
 * Learn more at https://developers.cloudflare.com/workers/
 */


export default {
  async fetch(request, env, ctx) {


    if (request.method === 'OPTIONS') {
        return new Response(null, {
          headers: {
            "Access-Control-Allow-Origin": "*",
            "Access-Control-Allow-Methods": "GET,HEAD,POST,OPTIONS",
            "Access-Control-Max-Age": "86400",
          }
        });
    }

    if (request.method == 'GET') {
        return new Response('Hello');
    }
 
    if (request.method === 'PUT') {
        // Note that you could require authentication for all requests
        // by moving this code to the top of the fetch function.
        const auth = request.headers.get('Authorization');
        const expectedAuth = `Bearer ${env.AUTH_SECRET}`;
  
        if (!auth || auth !== expectedAuth) {
          return new Response('Unauthorized', { status: 401 });
        }

        const corsHeaders = {
            "Access-Control-Allow-Origin": "*",
            "Access-Control-Allow-Methods": "GET,HEAD,POST,OPTIONS",
            "Access-Control-Max-Age": "86400",
        };
        
        const url = new URL(request.url);
        const key = url.pathname.slice(1);
        await env.MY_BUCKET.put(key, request.body);
        const data = `Object ${key} uploaded successfully!`;
        // return new Response(`Object ${key} uploaded successfully!`);
        return new Response(JSON.stringify(data), {
            headers: {
                ...corsHeaders,
                'Content-Type': 'application/json;charset=UTF-8'
            }
        })
    }
   },
};

Ranjan Mangla

R

Ranjan Mangla•1/12/24, 11:20 AM

now it is solved, added PUT method in OPTIONS request as allowed methods

Ranjan Mangla

R

Ranjan Mangla•1/12/24, 11:20 AM

Thank you very much @HardlyHolidayin’ ,was stuck on it for past one day

Ranjan Mangla

R

Ranjan Mangla•1/12/24, 11:20 AM

and got know about pre-flight requests today facehappy

facehappy

Deo Kumar

D

Deo Kumar•1/12/24, 12:43 PM

If anyone want to use photon-rs library which is available for node environment can try this fork. It works on Cloudflare Workers, Pages, Next js, node:
https://www.npmjs.com/package/@cf-wasm/photon

npm

@cf-wasm/photon

Photon library for Cloudflare workers. Latest version: 0.1.6, last published: an hour ago. Start using @cf-wasm/photon in your project by running

npm i @cf-wasm/photon

npm i @cf-wasm/photon

. There are no other projects in the npm registry using @cf-wasm/photon.

crossbeau

C

crossbeau•1/12/24, 10:07 PM

Is there a way to log out compatibility date and compatibility flags?

crossbeau

C

crossbeau•1/12/24, 10:08 PM

I manually created one worker a while ago and now trying to terraform it, and the code works on the manually created one and not the terraformed one. And i am thinking i need to match compatibility date

crossbeau

C

crossbeau•1/12/24, 10:08 PM

But unsure how to find

kian

K

kianOP•1/12/24, 10:10 PM

what's the code that doesn't work/the error

kian

K

kianOP•1/12/24, 10:11 PM

otherwise just open devtools & look at the scripts request

kian

K

kianOP•1/12/24, 10:11 PM

Ranjan Mangla

R

Ranjan Mangla•1/13/24, 6:04 AM

I have links to files on my ftp server, I can't ssh into server

Ranjan Mangla

R

Ranjan Mangla•1/13/24, 6:04 AM

Is there any way I can download those files in workers

Ranjan Mangla

R

Ranjan Mangla•1/13/24, 6:05 AM

If I only pass the link as a post request and it then downloads it and then transfer to R2

Ranjan Mangla

R

Ranjan Mangla•1/13/24, 6:05 AM

Fetch is not working

Ranjan Mangla

R

Ranjan Mangla•1/13/24, 6:05 AM

In this regard

Arma

A

Arma•1/13/24, 7:21 AM

Fetch only does HTTP so you can’t do FTP with that

Arma

A

Arma•1/13/24, 7:22 AM

Maybe there is a serverless package that lets you do ftp ?

Arma

A

Arma•1/13/24, 7:27 AM

There is a TCP api for workers so it’s definitely possible https://developers.cloudflare.com/workers/runtime-apis/tcp-sockets

TCP sockets · Cloudflare Workers docs

Use the

connect()

connect()

API to create outbound TCP connections from Workers.

Arma

A

Arma•1/13/24, 7:36 AM

Btw if you download each file to memory on the worker, it will only work for files up to 128 MB

Arma

A

Arma•1/13/24, 7:37 AM

Since your use case is a one time operation, I would simply download the FTP contents on my machine and upload them with the wrangler cli

Ranjan Mangla

R

Ranjan Mangla•1/13/24, 7:43 AM

Actually it's not, we are migrating data from our ftp server to R2

Ranjan Mangla

RRanjan Mangla Actually it's not, we are migrating data from our ftp server to R2

Hello, I’m Allie!

H

Hello, I’m Allie!•1/13/24, 8:03 AM

You can use rclone to move from FTP to R2 too

Hello, I’m Allie!

H

Hello, I’m Allie!•1/13/24, 8:03 AM

You can’t run it on a Worker, but it can be a tad faster

Hello, I’m Allie!

H

Hello, I’m Allie!•1/13/24, 8:03 AM

And less complex

Arma

A

Arma•1/13/24, 8:04 AM

My thinking is, you can either

implement FTP minimally over the workers TCP api and use that to connect to your existing file server, then stream the response to R2
use your existing file server’s HTTP api (if it has any) via fetch then put the response on R2

Ranjan Mangla

R

Ranjan Mangla•1/13/24, 8:06 AM

Thanks @HardlyHolidayin’ & @Arma

Ranjan Mangla

R

Ranjan Mangla•1/13/24, 8:06 AM

Will explore rclone one

Ranjan Mangla

R

Ranjan Mangla•1/13/24, 8:07 AM

@Arma can you shed more light on the TCP method, didn't understand properly

Arma

A

Arma•1/13/24, 8:16 AM

Most unsecured protocols like FTP, SMTP and HTTP run over TCP. There isn’t a standard api to use TCP with JavaScript because the browsers don’t allow it. But Workers do allow it so Cloudflare added a non standard api to use TCP directly. See the link above.

If you care enough to run your workload on Workers, this is a complicated but possible way to do it. You would look at the FTP spec online, and implement the minimum that you need, using the TCP stuff that Workers let you do. If you’re not comfortable with this endeavour there may be more sensible ways to solve your problem though

Arma

A

Arma•1/13/24, 8:17 AM

But this is the Workers channel so I’ll provide you with the Workers solution ahah

alen

A

alen•1/13/24, 8:52 AM

how do i use download from R2 in my website?

alen

A

alen•1/13/24, 8:53 AM

what link do i need to use?

export default {
    async fetch(request: Request, env: Env, ctx: ExecutionContext): Promise<Response> {
        const results: string[] = [];


        const options = {
            header: true,
            dynamicTyping: true,
        };


        const req = await request.formData();
        console.log(req);
        const result = papa.parse(req.get('blob'), options);
        console.log(result);

    
        return new Response('Hello World!');
    },
};

export default {
    async fetch(request: Request, env: Env, ctx: ExecutionContext): Promise<Response> {
        const results: string[] = [];


        const options = {
            header: true,
            dynamicTyping: true,
        };


        const req = await request.formData();
        console.log(req);
        const result = papa.parse(req.get('blob'), options);
        console.log(result);

    
        return new Response('Hello World!');
    },
};

export default {
  async fetch(request, env, ctx) {

    if (request.method == 'GET') {
        return new Response('Hello');
    }
 
    if (request.method === 'PUT') {
        // Note that you could require authentication for all requests
        // by moving this code to the top of the fetch function.
        const auth = request.headers.get('Authorization');
        const expectedAuth = `Bearer ${env.AUTH_SECRET}`;
  
        if (!auth || auth !== expectedAuth) {
          return new Response('Unauthorized', { status: 401 });
        }

        const corsHeaders = {
            "Access-Control-Allow-Origin": "*",
            "Access-Control-Allow-Methods": "GET,HEAD,POST,OPTIONS",
            "Access-Control-Max-Age": "86400",
        };
        
        const url = new URL(request.url);
        const key = url.pathname.slice(1);
        await env.MY_BUCKET.put(key, request.body);
        const data = `Object ${key} uploaded successfully!`;
        // return new Response(`Object ${key} uploaded successfully!`);
        return new Response(JSON.stringify(data), {
            headers: {
                ...corsHeaders,
                'Content-Type': 'application/json;charset=UTF-8'
            }
        })
    }
   },
};

export default {
  async fetch(request, env, ctx) {

    if (request.method == 'GET') {
        return new Response('Hello');
    }
 
    if (request.method === 'PUT') {
        // Note that you could require authentication for all requests
        // by moving this code to the top of the fetch function.
        const auth = request.headers.get('Authorization');
        const expectedAuth = `Bearer ${env.AUTH_SECRET}`;
  
        if (!auth || auth !== expectedAuth) {
          return new Response('Unauthorized', { status: 401 });
        }

        const corsHeaders = {
            "Access-Control-Allow-Origin": "*",
            "Access-Control-Allow-Methods": "GET,HEAD,POST,OPTIONS",
            "Access-Control-Max-Age": "86400",
        };
        
        const url = new URL(request.url);
        const key = url.pathname.slice(1);
        await env.MY_BUCKET.put(key, request.body);
        const data = `Object ${key} uploaded successfully!`;
        // return new Response(`Object ${key} uploaded successfully!`);
        return new Response(JSON.stringify(data), {
            headers: {
                ...corsHeaders,
                'Content-Type': 'application/json;charset=UTF-8'
            }
        })
    }
   },
};

/**
 * Welcome to Cloudflare Workers! This is your first worker.
 *
 * - Run `npm run dev` in your terminal to start a development server
 * - Open a browser tab at http://localhost:8787/ to see your worker in action
 * - Run `npm run deploy` to publish your worker
 *
 * Learn more at https://developers.cloudflare.com/workers/
 */


export default {
  async fetch(request, env, ctx) {


    if (request.method === 'OPTIONS') {
        return new Response(null, {
          headers: {
            "Access-Control-Allow-Origin": "*",
            "Access-Control-Allow-Methods": "GET,HEAD,POST,OPTIONS",
            "Access-Control-Max-Age": "86400",
          }
        });
    }

    if (request.method == 'GET') {
        return new Response('Hello');
    }
 
    if (request.method === 'PUT') {
        // Note that you could require authentication for all requests
        // by moving this code to the top of the fetch function.
        const auth = request.headers.get('Authorization');
        const expectedAuth = `Bearer ${env.AUTH_SECRET}`;
  
        if (!auth || auth !== expectedAuth) {
          return new Response('Unauthorized', { status: 401 });
        }

        const corsHeaders = {
            "Access-Control-Allow-Origin": "*",
            "Access-Control-Allow-Methods": "GET,HEAD,POST,OPTIONS",
            "Access-Control-Max-Age": "86400",
        };
        
        const url = new URL(request.url);
        const key = url.pathname.slice(1);
        await env.MY_BUCKET.put(key, request.body);
        const data = `Object ${key} uploaded successfully!`;
        // return new Response(`Object ${key} uploaded successfully!`);
        return new Response(JSON.stringify(data), {
            headers: {
                ...corsHeaders,
                'Content-Type': 'application/json;charset=UTF-8'
            }
        })
    }
   },
};

/**
 * Welcome to Cloudflare Workers! This is your first worker.
 *
 * - Run `npm run dev` in your terminal to start a development server
 * - Open a browser tab at http://localhost:8787/ to see your worker in action
 * - Run `npm run deploy` to publish your worker
 *
 * Learn more at https://developers.cloudflare.com/workers/
 */


export default {
  async fetch(request, env, ctx) {


    if (request.method === 'OPTIONS') {
        return new Response(null, {
          headers: {
            "Access-Control-Allow-Origin": "*",
            "Access-Control-Allow-Methods": "GET,HEAD,POST,OPTIONS",
            "Access-Control-Max-Age": "86400",
          }
        });
    }

    if (request.method == 'GET') {
        return new Response('Hello');
    }
 
    if (request.method === 'PUT') {
        // Note that you could require authentication for all requests
        // by moving this code to the top of the fetch function.
        const auth = request.headers.get('Authorization');
        const expectedAuth = `Bearer ${env.AUTH_SECRET}`;
  
        if (!auth || auth !== expectedAuth) {
          return new Response('Unauthorized', { status: 401 });
        }

        const corsHeaders = {
            "Access-Control-Allow-Origin": "*",
            "Access-Control-Allow-Methods": "GET,HEAD,POST,OPTIONS",
            "Access-Control-Max-Age": "86400",
        };
        
        const url = new URL(request.url);
        const key = url.pathname.slice(1);
        await env.MY_BUCKET.put(key, request.body);
        const data = `Object ${key} uploaded successfully!`;
        // return new Response(`Object ${key} uploaded successfully!`);
        return new Response(JSON.stringify(data), {
            headers: {
                ...corsHeaders,
                'Content-Type': 'application/json;charset=UTF-8'
            }
        })
    }
   },
};