How do I catch/log all exceptions in my Pages Functions? - Cloudflare Developers

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dave

Ddave How do I catch/log all exceptions in my Pages Functions?

James

J

James•8/21/23, 10:11 PM

Sentry Pages Plugin or similar perhaps? https://developers.cloudflare.com/pages/platform/functions/plugins/sentry/

James

J

James•8/21/23, 10:11 PM

These are effectively just middleware

James

J

James•8/21/23, 10:12 PM

In the case of Sentry, it's effectively a

try...catch

try...catch

next()

next()

wrapper: https://github.com/cloudflare/pages-plugins/blob/main/packages/sentry/functions/_middleware.ts

Cretezy

CCretezy Any update on this? `import`ing JSON doesn't seem to work

Cretezy

C

Cretezy•8/22/23, 4:46 AM

Not exactly sure how, but this works now!

Torzak

T

Torzak•8/22/23, 4:31 PM

Hello, Can someone explain to me why this behavior, I'm a beginner in JS ...

export function onRequest(context) {
  return new Response(Object.keys(context.request)) // return Empty output
  return new Response(Object.keys(context.request.cf)) // Return a lot of properties 
}

export function onRequest(context) {
  return new Response(Object.keys(context.request)) // return Empty output
  return new Response(Object.keys(context.request.cf)) // Return a lot of properties 
}

why i can't list properties and methods on context.request object with Object.keys() ? thank you

kian

K

kian•8/22/23, 4:43 PM

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/keys

given object's own enumerable string-keyed property names

kian

K

kian•8/22/23, 4:43 PM

The properties of most Web API types in Cloudflare Workers are not enumerable.

Torzak

T

Torzak•8/22/23, 4:56 PM

Thanks @kian

, So Is there a way/tips to list all the properties and methods of this context object without referring to the documentation here ? https://developers.cloudflare.com/pages/platform/functions/api-reference/#eventcontext I have the same kind of ouput with JSON.stringify method.

API reference · Cloudflare Pages docs

Learn about the APIs used within Pages Functions.

kian

K

kian•8/22/23, 5:06 PM

There aren't really any nice ways.

kian

K

kian•8/22/23, 5:06 PM

Even if you do some awful JSON.stringify workarounds, you still end up needing to handle

headers

headers

specifically amongst others.

Torzak

T

Torzak•8/22/23, 5:09 PM

export function onRequest(context) {
return new Response(JSON.stringify(context.request))
}

JSON.stringify output {} on my local test...

Capture_decran_2023-08-22_a_19.09.31.png

kian

Kkian Even if you do some awful JSON.stringify workarounds, you still end up needing t...

Torzak

T

Torzak•8/22/23, 5:10 PM

how did you output that ?

kian

K

kian•8/22/23, 5:10 PM

JSON.stringify(req, Object.getOwnPropertyNames(Object.getPrototypeOf(req)), '\t')

JSON.stringify(req, Object.getOwnPropertyNames(Object.getPrototypeOf(req)), '\t')

kian

Kkian ```js JSON.stringify(req, Object.getOwnPropertyNames(Object.getPrototypeOf(req))...

Torzak

T

Torzak•8/22/23, 5:10 PM

Thanks, i will try to understand that ....

kian

K

kian•8/22/23, 5:12 PM

You'd be better off creating your own logging accessing each property as necessary

kian

K

kian•8/22/23, 5:12 PM

i.e

console.log({
  url: req.url,
  method: req.method,
  ...
});

console.log({
  url: req.url,
  method: req.method,
  ...
});

Torzak

T

Torzak•8/22/23, 5:20 PM

I am just experimenting with pages, and I wanted to check if there were any undocumented data in the context object. I don't have much experience with JS, and I was surprised that I couldn't list all the properties of this object, as is possible in others programming language like with vardump() in PHP, dir() vars() in python .... for example. Thank you, @kian.

kian

K

kian•8/22/23, 5:25 PM

You can kind of do that like this...

for (const property in req) {
  console.log(`${property}: ${req[property]}`);
}

for (const property in req) {
  console.log(`${property}: ${req[property]}`);
}

kian

K

kian•8/22/23, 5:25 PM

Basically, properties on the Web API types are typically non-enumerable (so not picked up by

Object.keys()

Object.keys()

or

console.log()

console.log()

) and they're also on the prototype (so not picked up by

Object.getOwnPropertyNames()

Object.getOwnPropertyNames()

which looks at the instance) - but there are ways to print out what's on them.

kian

Kkian You can kind of do that like this... ```js for (const property in req) { cons...

kian

K

kian•8/22/23, 5:26 PM

kian

K

kian•8/22/23, 5:27 PM

It's an issue mostly unique to Workers - you can

console.log

console.log

a Web API type in Node/Browsers/etc

Torzak

T

Torzak•8/22/23, 5:28 PM

Very interesting information!

Original message was deleted

Johtozo

J

Johtozo•8/22/23, 6:33 PM

Found my problem. I wasn't running wrangler on the project directory itself and was running above it, since I have a collection of directories... silly me :- P works dandy now

smattmyers

S

smattmyers•8/24/23, 4:13 PM

Do I need to add routes to my project in order to get my functions to deploy? I used wrangler to generate an Angular Universal SSR Pages project and I added /functions directory to my root directory, but it does not seem like it's getting deployed, and the routes are definitely not working.

smattmyers

S

smattmyers•8/24/23, 5:51 PM

that makes sense...thanks!

xdeq

X

xdeq•8/25/23, 11:02 PM

No changes were made to the project, but after a successful build at the very end the following error started to appear. What is it and where did it come from?
(nuxt3, nitro, cloudflare-pages preset)

James

J

James•8/25/23, 11:15 PM

I would guess one of your dependencies got updated

xdeq

X

xdeq•8/25/23, 11:16 PM

@cherryjimbo No packages have been updated / removed / added

James

J

James•8/25/23, 11:17 PM

Are you pinning specific dependency versions and using a lockfile? If you're using versions like

^1.0.0

^1.0.0

(note the

), then any version compatible with

1.0.0

1.0.0

could be installed

James

J

James•8/25/23, 11:17 PM

As far as I know, nothing on the Pages end has changed, so something in your project must have, be in a dependency, or sub-dependency, etc.

James

J

James•8/25/23, 11:17 PM

My first recommenedation would be to try and reproduce locally, doing a completely fresh install of the project

Sam

S

Sam•8/26/23, 6:47 AM

I'm struggling to implement a Pages function on a local repository. I have a repository with the following structure:

|---- public
| index.html
|---- functions
| getFeed.js

My index.html looks like this:

<html>
<head>
    <script src="https://unpkg.com/htmx.org@1.9.4"></script>
    <script src="https://unpkg.com/hyperscript.org@0.9.11"></script>
</head>
<script>
function loadIndex() {
    console.log('test');
    htmx.ajax('GET', '/getFeed', {target: "#swap", headers: {
    }})
}
</script>
<body onload="loadIndex()">
...
</body>
</html>

<html>
<head>
    <script src="https://unpkg.com/htmx.org@1.9.4"></script>
    <script src="https://unpkg.com/hyperscript.org@0.9.11"></script>
</head>
<script>
function loadIndex() {
    console.log('test');
    htmx.ajax('GET', '/getFeed', {target: "#swap", headers: {
    }})
}
</script>
<body onload="loadIndex()">
...
</body>
</html>

When I load the site, I get a 404 error for the /getFeed request. I'm not sure if this is a problem with my directory setup, my routing, loading htmx, or anything else. Can someone help me address this?

Sam

S

Sam•8/26/23, 6:49 AM

The contents of my

functions/getFeed.js

functions/getFeed.js

file are currently

export const onRequestGet = () => {
  return new Response("Hello, world!")
}

export const onRequestGet = () => {
  return new Response("Hello, world!")
}

And it's still returning 404

slagathor

S

slagathor•8/26/23, 7:45 PM

Do functions work with NextJS deployments? Wrangler doesn't seem to be picking up my functions.

slagathor

Sslagathor Do functions work with NextJS deployments? Wrangler doesn't seem to be picking u...

James

J

James•8/26/23, 7:58 PM

If you are using

@cloudflare/next-on-pages

@cloudflare/next-on-pages

, the functions directory will not work as we generate our own

_worker.js

_worker.js

instead, and, as such, you should use Next.js Edge API routes instead.

James

JJames If you are using `@cloudflare/next-on-pages`, the functions directory will not w...

slagathor

S

slagathor•8/26/23, 8:02 PM

got it. ty!

Raindrops

RRaindrops hello there! is there a repo with functions examples? I kinda want to understand...

Fizzy Kombucha

F

Fizzy Kombucha•8/27/23, 3:31 AM

https://developers.cloudflare.com/pages/tutorials/build-an-api-with-pages-functions/
not a repo but detailed instructions for building one

Build an API for your front end using Pages Functions · Cloudflare ...

In this tutorial, you will build a full stack Pages application. Your application will contain:

sakuta

S

sakuta•8/27/23, 4:38 PM

do functions run in front of the cache just as workers?

kian

K

kian•8/27/23, 4:38 PM

Yup

kian

K

kian•8/27/23, 4:39 PM

Well, Pages itself is a Worker so there isn’t really any origin cache in the first place - just the Cache API

Erisa

E

Erisa•8/27/23, 5:56 PM

Static assets have their own internal cache

Erisa

E

Erisa•8/27/23, 5:57 PM

dynamic responses from functions do not, so those need to use cache api

Asatsuki

A

Asatsuki•8/28/23, 5:04 PM

has anyone gotten langchain to work on cloudflare pages? it says

crypto.getHashes has not been implemented yet

crypto.getHashes has not been implemented yet

when i try to deploy

Shivam

S

Shivam•8/29/23, 11:19 AM

hello, can anyone help me with this issue?
functions

Asatsuki

AAsatsuki has anyone gotten langchain to work on cloudflare pages? it says `crypto.getHash...

Vero

V

Vero•8/29/23, 3:24 PM

It should work using fetch()

Vero

VVero It should work using fetch()

Asatsuki

A

Asatsuki•8/29/23, 4:36 PM

Thanks for the reply. Can you specify where I should use fetch()? the error occurs in deployment when i have this inside /server/api/query.ts (using nuxt 3):

import { OpenAI } from 'langchain/llms/openai';

export default defineEventHandler(async e => {
   const model = new OpenAI(); //OPENAI_API_KEY set in env
});

import { OpenAI } from 'langchain/llms/openai';

export default defineEventHandler(async e => {
   const model = new OpenAI(); //OPENAI_API_KEY set in env
});

Unsmart

U

Unsmart•8/29/23, 4:41 PM

I would assume both are exactly the same results just slightly different response

<html>
<head>
    <script src="https://unpkg.com/htmx.org@1.9.4"></script>
    <script src="https://unpkg.com/hyperscript.org@0.9.11"></script>
</head>
<script>
function loadIndex() {
    console.log('test');
    htmx.ajax('GET', '/getFeed', {target: "#swap", headers: {
    }})
}
</script>
<body onload="loadIndex()">
...
</body>
</html>

<html>
<head>
    <script src="https://unpkg.com/htmx.org@1.9.4"></script>
    <script src="https://unpkg.com/hyperscript.org@0.9.11"></script>
</head>
<script>
function loadIndex() {
    console.log('test');
    htmx.ajax('GET', '/getFeed', {target: "#swap", headers: {
    }})
}
</script>
<body onload="loadIndex()">
...
</body>
</html>