zing Posts - Deno

zing

•Created by zing on 2/15/2025 in #help

Deno Kv: "Database is locked" on enqueue

I'm running 2 Deno services. Service 1 gathers info and posts it to service 2 via HTTP post, where 2 immediately offloads the request to a Deno.kv queue and returns. There are a lot of posts being made, and once a couple thousand events are queued I'm noticing that inconsistently service 2 will throw the following error:

[uncaught application error]: TypeError - database is locked

request: {
  url: "http://localhost:8080/api/events",
  method: "POST",
  hasBody: true
}
response: { status: 500, type: "text", hasBody: true, writable: true }

    at async doAtomicWriteInPlace (ext:deno_kv/01_db.ts:629:10)
    at async Kv.enqueue (ext:deno_kv/01_db.ts:163:26)
    at async file:///<my_filepath>/src/api/events.controller.ts:13:5
    at async dispatch (https://jsr.io/@oak/oak/17.0.0/middleware.ts:90:7)
    at async dispatch (https://jsr.io/@oak/oak/17.0.0/middleware.ts:90:7)
    at async dispatch (https://jsr.io/@oak/oak/17.0.0/middleware.ts:90:7)
    at async default (file:///<my_filepath>/src/middleware/errorhandling.middleware.ts:9:9)
    at async dispatch (https://jsr.io/@oak/oak/17.0.0/middleware.ts:90:7)
    at async Application.#handleRequest (https://jsr.io/@oak/oak/17.0.0/application.ts:605:9)

[uncaught application error]: TypeError - database is locked

request: {
  url: "http://localhost:8080/api/events",
  method: "POST",
  hasBody: true
}
response: { status: 500, type: "text", hasBody: true, writable: true }

    at async doAtomicWriteInPlace (ext:deno_kv/01_db.ts:629:10)
    at async Kv.enqueue (ext:deno_kv/01_db.ts:163:26)
    at async file:///<my_filepath>/src/api/events.controller.ts:13:5
    at async dispatch (https://jsr.io/@oak/oak/17.0.0/middleware.ts:90:7)
    at async dispatch (https://jsr.io/@oak/oak/17.0.0/middleware.ts:90:7)
    at async dispatch (https://jsr.io/@oak/oak/17.0.0/middleware.ts:90:7)
    at async default (file:///<my_filepath>/src/middleware/errorhandling.middleware.ts:9:9)
    at async dispatch (https://jsr.io/@oak/oak/17.0.0/middleware.ts:90:7)
    at async Application.#handleRequest (https://jsr.io/@oak/oak/17.0.0/application.ts:605:9)

the controller handling these calls looks like the following:

eventsRouter.post("/", async (ctx) => {
    const data: Dto = await ctx.request.body.json();

    await kv.enqueue({ type: "handle_event", details: data }, cfg.KV_OPTIONS);

    ctx.response.status = 200;
});

eventsRouter.post("/", async (ctx) => {
    const data: Dto = await ctx.request.body.json();

    await kv.enqueue({ type: "handle_event", details: data }, cfg.KV_OPTIONS);

    ctx.response.status = 200;
});

It doesn't seem to be breaking consistently after 'x amount of queued items' or anything like that, from what I can see. I'm not quite sure what is causing it, perhaps anyone else has some experience with this? Thanks for any help

3 replies

DDeno

•Created by zing on 1/23/2025 in #help

Different behaviour between Node and Deno with npm package

I'd like to use deno for a project that requires packages which are only available on npm. The issue I'm having is that executing the same script on deno and node is producing different results. - on node, the execution produces the expected results(some

"forward" logs)
- on

deno

, the execution pauses for a second at startup and then exits with no logs

The script I'm working on is as follows:
```ts
import { createChainSynchronizationClient, createInteractionContext } from 'npm:@cardano-ogmios/client'

export const createContext = () => createInteractionContext(
    err => console.error(err),
    () => console.log("Connection closed."),
    { connection: { host: "<url>" , port: 443, tls: true } }
);

export async function runExample() {
    const context = await createContext();
    // console.log('here')
    const client = await createChainSynchronizationClient(context, {
        rollForward: async () => { console.log("forward") },
        rollBackward: async () => { console.log("backward") }
    });
    await client.resume();
}

runExample()
```
uncommenting the

console.log('here') and running with deno reveals the script isn't getting there, so presumably something is being held up inside createContext, which is calling createInteractoinContext(..)`. Obviously this is a function in the lib so I'm not expecting anyone to know whats wrong, but I was hoping someone with knowledge about the way deno interacts with npm packages might suggest what I should look for within the lib that could cause this 'silent exit'? thanks

2 replies

DDeno

•Created by zing on 1/14/2025 in #help

Relative import path "oak/router" not prefixed with / or ./ or ../ and not in import map

I get the above message when attempting to deploy to Deno Deploy via github actions. The same does not occur when running locally with deno run -A src/main.ts. deploy.yaml:

      # ...
      - name: Upload to Deno Deploy
        uses: denoland/deployctl@v1
        with:
          project: "<proj name>"
          entrypoint: "./src/main.ts"
          root: ""
          import-map: "./deno.json"

      # ...
      - name: Upload to Deno Deploy
        uses: denoland/deployctl@v1
        with:
          project: "<proj name>"
          entrypoint: "./src/main.ts"
          root: ""
          import-map: "./deno.json"

deno.json:

  // ...
  "imports": {
    "@std/assert": "jsr:@std/assert@1",
    "@std/dotenv": "jsr:@std/dotenv",
    "@std/path": "jsr:@std/path",
    "@types/pg": "npm:@types/pg@^8.11.10",
    "drizzle-kit": "npm:drizzle-kit@^0.30.1",
    "drizzle-orm": "npm:drizzle-orm@^0.38.3",
    "oak": "jsr:@oak/oak@17.0.0",
    "dotenv": "https://deno.land/x/dotenv@v3.2.2/mod.ts",
    "deno-postgres": "https://deno.land/x/postgres@v0.19.3/mod.ts",
    "joi": "npm:joi@17.13.3",
    "pg": "npm:pg@^8.13.1"
  }

  // ...
  "imports": {
    "@std/assert": "jsr:@std/assert@1",
    "@std/dotenv": "jsr:@std/dotenv",
    "@std/path": "jsr:@std/path",
    "@types/pg": "npm:@types/pg@^8.11.10",
    "drizzle-kit": "npm:drizzle-kit@^0.30.1",
    "drizzle-orm": "npm:drizzle-orm@^0.38.3",
    "oak": "jsr:@oak/oak@17.0.0",
    "dotenv": "https://deno.land/x/dotenv@v3.2.2/mod.ts",
    "deno-postgres": "https://deno.land/x/postgres@v0.19.3/mod.ts",
    "joi": "npm:joi@17.13.3",
    "pg": "npm:pg@^8.13.1"
  }

src/main.ts

import { Router } from "oak/router";
// ...

import { Router } from "oak/router";
// ...

I know what the error means and I've fixed it before in other cases. From what I can see my configuration is correct, so I'm trying to figure out why I might be getting it only in the action execution. Could anyone lend an eye? thanks

5 replies

DDeno

•Created by zing on 11/17/2024 in #help

Sequential queue processing with Deno KV listenQueue?

I'm working on an API endpoint that needs to process lots of calls every second. I want to make this call asynchronous so that the API returns fast and I can offload the data to be processed in the background, so I thought of using Deno.kv queues(https://docs.deno.com/deploy/kv/manual/queue_overview/). The only issue is that there is a lot of async code inside the processing jobs, and when I queue up a lot of them they seem to overlap in processing, which causes issues when accessing shared resources(db connections specifically). Is there a way to make kv.listenQueue process each entry in sequence? This is effectively my queue code:

const kv = await Deno.openKv();

kv.listenQueue(async (msg: EvaluateRequest) => { await service.evaluate(msg) })

const kv = await Deno.openKv();

kv.listenQueue(async (msg: EvaluateRequest) => { await service.evaluate(msg) })

3 replies

DDeno

•Created by zing on 7/11/2023 in #help

Fresh pattern help

Could anyone possibly help guide me to understand the 'freshest' pattern for the following, please? When a user hits / I load a login page, and once he submits the form, the server generates some session data in the POST handler for /, and then redirects(send back a 303) to /chat. There is an island on /chat which needs to contain the session data. How would I redirect from the form POST handler, to the /chat page and make sure that my state is passed to the island? In react or similar I would handle the 'form submission' in javascript and cache the returned session data before redirecting to /chat. Since fresh seems to promote the use of native forms I'm trying to learn how I would handle this situation. I'm thinking of setting a cookie in the redirect, to then be sent with the /chat GET, which I can use to return the page with session data inside. Is that common? Thanks!

7 replies