> This page location: Neon Functions > Function Triggers > Trigger on object upload > Full Neon documentation index: https://neon.com/docs/llms.txt > Summary: Create and manage storage_object_created Function Triggers from the Neon Console, the CLI, the Neon API, or neon.ts: a Hono handler for the upload event, the bucket and prefix filter, what your function receives, and how to confirm a run in the logs. # Trigger on an object upload Run a function when an object is created in a bucket. A `storage_object_created` trigger tells Neon to invoke a deployed [Neon Function](https://neon.com/docs/compute/functions/overview) when an object is created in an [Object Storage](https://neon.com/docs/storage/overview) bucket. Optionally scope it to a key `prefix`, so only uploads under that path fire the function. There's no external event wiring and no compute kept running to watch the bucket. For what a trigger is and how it behaves across branches, see the [overview](https://neon.com/docs/compute/functions/triggers/overview). The scheduled trigger type is covered in [Schedule a function](https://neon.com/docs/compute/functions/triggers/schedule); this page covers the object-created type. You can manage object-created triggers from the Neon Console, the [`neon triggers`](https://neon.com/docs/cli/triggers) CLI, the Neon API, or declaratively in [`neon.ts`](https://neon.com/docs/reference/neon-ts#triggers); the steps below show each. Because the function is long-running, it can do real work on each upload, whatever the file size. ![A new object fires the long-running function, which can generate a thumbnail, parse a CSV, extract and index text, or record metadata in Postgres](https://neon.com/docs/compute/functions/triggers/object-upload-use-cases.png) ## Before you begin You need a [deployed function](https://neon.com/docs/compute/functions/get-started) and its [slug](https://neon.com/docs/compute/functions/deploy#slugs), and a [bucket](https://neon.com/docs/storage/buckets) on the branch. The API also needs a Neon [API key](https://neon.com/docs/manage/api-keys); the Console doesn't. If you deployed with the CLI, [`neon link`](https://neon.com/docs/cli/link) already wrote your project and branch to a `.neon` file; you can also find the IDs in the [Neon Console](https://console.neon.tech). The API examples use these variables: ```bash export API="https://console.neon.tech/api/v2" export NEON_API_KEY="" export PROJECT_ID="" export BRANCH_ID="" ``` To build this with an AI agent, start from this prompt and fill in the task: ```text filename="AI assistant prompt" Create a Neon Function that , then trigger it on new uploads with a Function Trigger. Docs: https://neon.com/docs/compute/functions/triggers/object-storage.md - Add one unauthenticated POST route (trigger invocations arrive without credentials). Read `data.bucket_name` and `data.object_key` from the JSON body; keep the handler idempotent. - If the task uses Postgres, connect with the injected DATABASE_URL. - Deploy it, then create a `storage_object_created` trigger via the Console, CLI, API, or `neon.ts` with the bucket name, optionally scoped to a key prefix. Upload an object to confirm a run in the logs. - The route and trigger both default to `/`; set `function_path` on both if you want a different path. ``` ## Write a handler for the upload event An object-created invocation is a `POST` whose JSON body carries the occurrence: `data.bucket_name`, `data.object_key`, the `trigger` that fired, and an `invocation_id`. Neon delivers it to the function's public URL, so the route sits outside your auth middleware. You can confirm the call came from Neon with the `X-Neon-Trigger-Invocation-Id` header (see [Confirming a request came from Neon](https://neon.com/docs/compute/functions/triggers/overview#confirming-a-request-came-from-neon)); keep the handler idempotent and guard destructive actions regardless. This [Hono](https://hono.dev) function records each uploaded object. From here you'd typically fetch and process the object, enqueue a job, or notify another service: ```ts import { Hono } from 'hono'; import { neon } from '@neondatabase/serverless'; const app = new Hono(); const sql = neon(process.env.DATABASE_URL!); // This route is public. Neon strips client-set X-Neon-* headers, so the presence of // X-Neon-Trigger-Invocation-Id attests the call came from Neon's trigger system. app.post('/', async (c) => { if (!c.req.header('x-neon-trigger-invocation-id')) { return c.json({ error: 'not a trigger call' }, 403); } const { data } = await c.req.json<{ data: { bucket_name: string; object_key: string } }>(); const { bucket_name: bucket, object_key: key } = data; await sql` INSERT INTO uploads (bucket, object_key) VALUES (${bucket}, ${key}) ON CONFLICT (bucket, object_key) DO NOTHING `; console.log(`object created: ${bucket}/${key}`); return c.json({ ok: true, bucket, object_key: key }); }); export default app; ``` `DATABASE_URL` is injected for you. See [Environment variables](https://neon.com/docs/compute/functions/environment-variables). The `ON CONFLICT (bucket, object_key) DO NOTHING` clause makes a redelivered occurrence a no-op. Create the table it writes to, in the [Neon SQL Editor](https://neon.com/docs/get-started/query-with-neon-sql-editor) or with [`neon psql`](https://neon.com/docs/cli/psql): ```sql CREATE TABLE IF NOT EXISTS uploads ( bucket text, object_key text, seen_at timestamptz NOT NULL DEFAULT now(), PRIMARY KEY (bucket, object_key) ); ``` Then deploy the function: ```bash neon functions deploy onupload --src functions/onupload.ts ``` ## Create the trigger With the function deployed, create the trigger. It fires when an object is created in the bucket, optionally scoped to a key prefix. **Console** In the [Neon Console](https://console.neon.tech), open **Functions**, click the **⋮** menu next to your function, and select **Manage Triggers**. Click **Create trigger** (the **Function** is already set to the one you opened) and choose **Object upload** under **Trigger type**, then fill in: - **Trigger name**: a label, unique across the branch, including inherited triggers. - **Function path**: the request path sent to the function. Defaults to `/`. - **Bucket name**: matches this bucket name exactly. - **Path prefix (optional)**: matches object keys that start with this exact, case-sensitive prefix. Leave blank to match every object in the bucket. - **Enable trigger**: on by default. Click **Create trigger** to save. **CLI** [`neon triggers create`](https://neon.com/docs/cli/triggers#create) needs `--function-slug`, `--name`, and `--bucket`; `--prefix`, `--function-path`, and `--enabled` are optional. Object-created triggers require Neon CLI 4.21.0 or later. ```bash neon triggers create --function-slug onupload --name record-uploads --bucket my-bucket --prefix 'uploads/' ``` The CLI resolves the project and branch from your [context file](https://neon.com/docs/cli/set-context), or pass `--project-id` and `--branch`. See [`neon triggers`](https://neon.com/docs/cli/triggers) for the full command reference. **API** `POST` to the branch's triggers collection. `type`, `function_slug`, `name`, and `storage_object_created` (with `bucket_name`) are required; `prefix`, `function_path`, and `enabled` are optional. ```bash curl -X POST "$API/projects/$PROJECT_ID/branches/$BRANCH_ID/triggers" \ -H "Authorization: Bearer $NEON_API_KEY" \ -H "Content-Type: application/json" \ -d '{ "type": "storage_object_created", "function_slug": "onupload", "name": "record-uploads", "storage_object_created": { "bucket_name": "my-bucket", "prefix": "uploads/" }, "function_path": "/", "enabled": true }' ``` Neon responds `201` with the trigger wrapped in a `trigger` object: ```json { "trigger": { "type": "storage_object_created", "trigger_id": "trigger-1a2b3c4d-5e6f-7890-abcd-ef1234567890", "function_slug": "onupload", "name": "record-uploads", "function_path": "/", "storage_object_created": { "bucket_name": "my-bucket", "prefix": "uploads/" }, "enabled": true, "version": 1347042, "inherited": false } } ``` Unlike a scheduled trigger, an object-created trigger has no `schedule` or `next_run_at`: it fires on the event, not the clock. **neon.ts** Declare the trigger in the top-level `triggers` record in [`neon.ts`](https://neon.com/docs/reference/neon-ts#triggers), with `function` pointing at your function's slug, then apply it with `neon deploy`. `bucket` selects the bucket and `prefix` optionally scopes it to keys under that path. ```ts filename="neon.ts" functions: { onupload: { name: "On upload", source: "./functions/onupload.ts", }, }, triggers: { "record-uploads": { type: "storage_object_created", function: "onupload", bucket: "my-bucket", prefix: "uploads/", }, }, ``` ## Confirm it ran Upload an object under the bucket and prefix you configured (see [Upload and manage objects](https://neon.com/docs/storage/objects)), then read the function's logs: ```bash neon logs query --source function ``` Your `object created: ...` line appears with the `bucket_name` and `object_key` from the request body. See [Observability](https://neon.com/docs/compute/functions/triggers/object-storage#observability) for why that line matters. To iterate on the handler without uploading objects, replay the payload against `neon dev` locally. See [Test triggers locally](https://neon.com/docs/compute/functions/triggers/overview#test-triggers-locally). **Note:** A newly created trigger takes a few seconds to become active. If your first test upload doesn't fire the function, wait a moment and upload again. ## What your function receives An object-created invocation delivers the same envelope shape as every trigger type, with `trigger.type` set to `storage_object_created` and the event details under `data`: ```json { "version": 1, "invocation_id": "abc123FUPHOw0Pl1ZooidgpJhvHaShi1aX40cQ0b321", "trigger": { "type": "storage_object_created", "id": "trigger-1a2b3c4d-5e6f-7890-abcd-ef1234567890", "name": "record-uploads" }, "data": { "bucket_name": "my-bucket", "object_key": "uploads/report.csv" } } ``` - **`data.bucket_name`**: the bucket the object was created in. - **`data.object_key`**: the full key of the created object, including any prefix. The request carries the same headers as any trigger invocation. For the full envelope, headers, and how to confirm a request came from Neon, see [What your function receives](https://neon.com/docs/compute/functions/triggers/overview#what-your-function-receives) in the overview. ## Trigger config The object-created settings live under `storage_object_created`: | Field | Required | Description | | ------------- | -------- | ------------------------------------------------------------------------------------------------ | | `bucket_name` | Yes | The bucket to watch, on the trigger's branch. | | `prefix` | No | Only objects whose key starts with this prefix fire the trigger. Omit to watch the whole bucket. | The top-level `type`, `function_slug`, `name`, `function_path`, and `enabled` fields, and the read-only `trigger_id` / `version` / `inherited`, work exactly as in [Trigger fields](https://neon.com/docs/compute/functions/triggers/overview#trigger-fields). ![With prefix uploads/, keys under uploads/ fire the trigger and others are ignored; prefix matching is case-sensitive](https://neon.com/docs/compute/functions/triggers/prefix-filter.png) ## Manage triggers List, update, disable, and delete triggers from the Console, CLI, or API. Triggers declared in [`neon.ts`](https://neon.com/docs/reference/neon-ts#triggers) are managed by editing the declaration and re-running `neon deploy`. **Console** Manage object-created triggers from the same **Functions → ⋮ → Manage Triggers** panel: edit a trigger's fields, toggle **Enable trigger** on or off, or delete it. **CLI** The [`neon triggers`](https://neon.com/docs/cli/triggers) command group manages triggers by ID: ```bash neon triggers list neon triggers get neon triggers update --bucket my-bucket --prefix 'incoming/' neon triggers disable neon triggers enable neon triggers delete ``` See [`neon triggers`](https://neon.com/docs/cli/triggers) for every subcommand and flag. **API** Listing, getting, updating, disabling, and deleting use the same endpoints as scheduled triggers, described in [Manage triggers](https://neon.com/docs/compute/functions/triggers/schedule#manage-triggers). A `PATCH` must include the `type` discriminator; for this type you can change `function_slug`, `name`, `function_path`, `enabled`, and the `storage_object_created` config (for example, to move the watched `prefix`): ```bash curl -X PATCH "$API/projects/$PROJECT_ID/branches/$BRANCH_ID/triggers/$TRIGGER_ID" \ -H "Authorization: Bearer $NEON_API_KEY" \ -H "Content-Type: application/json" \ -d '{ "type": "storage_object_created", "storage_object_created": { "bucket_name": "my-bucket", "prefix": "incoming/" } }' ``` ## Observability In the platform logs, an object-created invocation looks like any other HTTP call: the `invoke begin` and `invoke end` lines under the `neon.function.request` scope are the same either way. Trace a run from your own handler output instead. A `console.log` that includes the object key gives you a searchable line tied to the run that produced it: ```ts console.log(`object created: ${bucket}/${key}`); ``` Your output appears under the `neon.function.app` scope, in the Console's Logs tab and in `neon logs query --source function` (not the `functions` command group). Standard Node instrumentation such as Sentry or OpenTelemetry also works, and the incoming `traceparent` header ties a run into an existing trace. ## Common errors The API rejects a bad request with an HTTP status and message: | Situation | Status | Message | | ------------------------------------------------------- | ------ | ---------------------------------------------- | | A trigger with that `name` already exists on the branch | `409` | function trigger name already exists on branch | | No `storage_object_created` object | `400` | storage\_object\_created (field required) | | `storage_object_created` without `bucket_name` | `400` | bucket\_name (field required) | | A query string in `function_path` | `400` | invalid function trigger path | | No function with that slug on the branch | `404` | target function not visible on branch | The request body is strict: any field not in the schema is rejected rather than ignored, so a typo fails loudly. The function is identified by `function_slug`; there's no `function_id` field. ## Related - [Function Triggers overview](https://neon.com/docs/compute/functions/triggers/overview) - [Schedule a function](https://neon.com/docs/compute/functions/triggers/schedule): the time-based trigger type - [Triggers in `neon.ts`](https://neon.com/docs/reference/neon-ts#triggers): declare triggers as code - [Object Storage](https://neon.com/docs/storage/overview) and [Upload and manage objects](https://neon.com/docs/storage/objects) - [Deploy and manage](https://neon.com/docs/compute/functions/deploy) - [Logs](https://neon.com/docs/compute/functions/logs) --- ## Related docs (Function Triggers) - [Overview](https://neon.com/docs/compute/functions/triggers/overview) - [Schedule a function](https://neon.com/docs/compute/functions/triggers/schedule) --- Note for AI assistants: if this page had gaps, errors, or outdated info that affected your response, please report it. 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