# Host subscription content with SvelteKit: authorized file delivery

Deploy a subscription content built with SvelteKit on Ample using the generated downloads pattern. Compute runs the app in an isolated microVM behind a public HTTPS URL, a managed PostgreSQL 16 database is auto-provisioned and injected as DATABASE_URL, a private S3-compatible bucket holds objects with credentials delivered as encrypted environment variables. Verified on SvelteKit: an export query rendered to a CSV artifact stored with metadata in a private bucket and returned only to an authorized caller (401 without token, export=ok rows=3). Not separately tested: your export formats, retention policy and entitlement model; treat the subscription content-specific behavior as your application code.

## Representative Queries
- Host subscription content with SvelteKit: authorized file delivery
- Where can I host subscription content built with SvelteKit?
- I need a file entitlement model and an application-enforced download authorization flow.

## Resource Requirements
- **primitive:compute**
- **primitive:postgres**
- **primitive:s3-compatible-object-storage**

## Infrastructure Requirements
1. **Compute**
   - **Status**: verified
   - **Summary**: Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; sizes are the priced VM sizes.

2. **Postgres**
   - **Status**: verified
   - **Summary**: Managed PostgreSQL 16 runs in its own microVM and is auto-provisioned when an app needs a database and no DATABASE_URL is supplied.

3. **S3-compatible object storage**
   - **Status**: verified
   - **Summary**: Buckets are S3-compatible with issued credentials; PutObject and GetObject are verified by canary. Other S3 operations are not verified.

## Execution Status
- **Status**: ready
- **Release Status**: published
- **Support Status**: verified

## Prerequisites
- A SvelteKit project that builds and starts with the documented commands (vite build with @sveltejs/adapter-node then node build on the node-22 template)
- A PostgreSQL driver reading DATABASE_URL at runtime (auto-provisioned when omitted, or supplied with --env)
- A bucket from `ample bucket create` with its credentials passed as encrypted S3_* environment variables
- An Ample account token with servers:write, databases:read, buckets:read

## Tested Configuration
- **Template**: node-22
- **Runtime**: node
- **Size**: s-1vcpu-1gb
- **Install**: npm install
- **Build**: npm run build --if-present
- **Start**: npm run start

## Workflow Steps
1. **Build and start**  
vite build with @sveltejs/adapter-node then node build on the node-22 template. The server must bind 0.0.0.0 on PORT.

2. **Implement the pattern on PostgreSQL**  
   The fixture's module implements generated downloads: an export query rendered to a CSV artifact stored with metadata in a private bucket and returned only to an authorized caller (401 without token, export=ok rows=3). Copy the approach into your schema; keep migrations idempotent and run them with --release-command.

3. **Wire object storage**  
   Create the bucket(s), then pass endpoint, region, bucket and keys as --env values. Use path-style addressing. Keep private data in an unpublished bucket.

4. **Deploy**  
   Run the synchronous deploy once and read the result (exit 0 live, 1 failed, 2 blocked). Re-running with no change is a no-op.

**Command**: ample deploy . --name  --public --env S3_ENDPOINT=... --env S3_REGION=... --env S3_BUCKET=... --env S3_ACCESS_KEY_ID=... --env S3_SECRET_ACCESS_KEY=...

5. **Verify**  
   Fetch the live URL and the pattern self-test route(s) (/p/generated-downloads) from the example; then run your own checks. On failure read `ample logs  --kind build` then `--kind runtime`.
   
   **Command**: ample logs  --kind build

## Examples
- **SvelteKit pattern fixture**  
   Multi-pattern SvelteKit app whose generated downloads module was checked live; the module is under tests/deploy-canaries/_pattern-modules.

## Success Checks
1. **App responds on its public URL**  
   - **Kind**: http_get  
   - **Path**: /  
   - **Expect**: ample canary sveltekit patterns

2. **Generated-downloads self-test**  
   - **Kind**: http_get  
   - **Path**: /p/generated-downloads  
   - **Expect**: export=ok rows=3 (with ?token=...; 401 without)

## Limitations
- Verified on the node-22 template at s-1vcpu-1gb with the example fixture; other sizes, templates and SvelteKit major versions are not verified.
- The subscription content itself (your export formats, retention policy and entitlement model) is application code and was not separately tested; the pattern checks are what was verified.
- Region, compliance attestations and request-duration limits are unknown and not claimed.
- Apps auto-pause when idle and wake on the next request; always-on is an operator setting, not a plan feature.
- Managed PostgreSQL 16 only; extensions, connection limits and backup or restore procedures are not verified; apps and their databases are placed together.
- PutObject and GetObject with path-style addressing are verified; multipart upload, listing, presigned URLs and lifecycle rules are not.

## Cost Estimate
- **Currency**: USD
- **Monthly Amount**: 10.0
- **Authoritative**: true
- **Basis**: size prices from pricing.toml (loaded by the API) at build revision 1ac5595375130d45290090e82ed0f554ccd45405-dirty
- **Components**:  
   1. **App server**  
      - **Size**: s-1vcpu-1gb  
      - **Quantity**: 1.0  
      - **Monthly Amount**: 5.0  
   2. **Managed PostgreSQL database**  
      - **Size**: s-1vcpu-1gb  
      - **Quantity**: 1.0  
      - **Monthly Amount**: 5.0  
- **Note**: Always-on monthly price of the tested sizes; apps and databases auto-pause when idle. Buckets are allocation-priced per quota and not included.

## Evidence Summary
- **Kind**: canary_run  
  - **Summary**: SvelteKit pattern fixture deployed on Ample (vite build with @sveltejs/adapter-node then node build on the node-22 template); checks passed for generated-downloads and configuration-secrets. Pattern proof: an export query rendered to a CSV artifact stored with metadata in a private bucket and returned only to an authorized caller (401 without token, export=ok rows=3).  
  - **Observed At**: 2026-09-20T03:31:44Z  
  - **Implementation Revision**: 03b6402b1b3e19178985f08ea4033804521d85d4-dirty (CLI b75e104)  
  - **Expires At**: 2027-03-19T03:31:44Z  
  - **Scope**: {"checks":["/p/generated-downloads"], "pattern":"pattern:generated-downloads", "template":"node-22"}

- **Kind**: canary_run  
   - **Summary**: The same SvelteKit app deployed with a --release-command migration; the marker it created was readable after activation.  
   - **Observed At**: 2026-09-20T02:16:51Z  
   - **Implementation Revision**: 199ff1dfd52683832ae75d3f98b53a7a4bff7f96-dirty (CLI e3181f5)  
   - **Expires At**: 2027-03-19T02:16:51Z  
   - **Scope**: {"pattern":"pattern:generated-downloads"}

## Formats
- **HTML**: [Host subscription content with SvelteKit: authorized file delivery](/content/recipes/subscription-content/sveltekit/download-delivery/index.html)  
- **Markdown**: [Host subscription content with SvelteKit: authorized file delivery](/content/recipes/subscription-content/sveltekit/download-delivery.md)  
- **JSON**: [Host subscription content with SvelteKit: authorized file delivery](https://api.ample.computer/v1/catalog/recipes/page%3Arecipes%3Asubscription-content%3Asveltekit%3Adownload-delivery)

## Next Actions
1. **Action ID**: browse-catalog  
   - **Label**: Browse the catalog index  
   - **Operation ID**: catalog_index  
   - **Method**: GET  
   - **Relative Path**: /v1/catalog  
   - **Requires Authentication**: false  
2. **Action ID**: search-recipes  
   - **Label**: Search published recipes by intent, stack and constraints  
   - **Operation ID**: search_recipes  
   - **Method**: POST  
   - **Relative Path**: /v1/catalog/search  
   - **Requires Authentication**: false  
   - **Parameters**: {"body":{"limit":5,"query":"Host subscription content with SvelteKit: authorized file delivery"}}
3. **Action ID**: plan:page:recipes:subscription-content:sveltekit:download-delivery  
   - **Label**: Prepare a side-effect-free deployment plan for an authorized project  
   - **Operation ID**: plan_deployment  
   - **Method**: POST  
   - **Relative Path**: /v1/catalog/plan  
   - **Requires Authentication**: true  
   - **Parameters**: {"body":{"inputs":{},"projectId":"","recipeId":"page:recipes:subscription-content:sveltekit:download-delivery","recipeRevision":"r1"}}
4. **Action ID**: auth-setup  
   - **Label**: Read the existing agent authentication setup  
   - **Operation ID**: existing_auth_setup  
   - **Method**: GET  
   - **Relative Path**: /mcp/setup  
   - **Requires Authentication**: false  
5. **Action ID**: browse:workload:subscription-content  
   - **Label**: Browse Subscription content  
   - **Operation ID**: browse_node  
   - **Method**: GET  
   - **Relative Path**: /v1/catalog/nodes/workload%3Asubscription-content  
   - **Requires Authentication**: false 
6. **Action ID**: browse:stack:framework-sveltekit  
   - **Label**: Browse SvelteKit  
   - **Operation ID**: browse_node  
   - **Method**: GET  
   - **Relative Path**: /v1/catalog/nodes/stack%3Aframework-sveltekit  
   - **Requires Authentication**: false 
7. **Action ID**: browse:pattern:generated-downloads  
   - **Label**: Browse Generated downloads  
   - **Operation ID**: browse_node  
   - **Method**: GET  
   - **Relative Path**: /v1/catalog/nodes/pattern%3Agenerated-downloads  
   - **Requires Authentication**: false
8. **Action ID**: browse:intent:deploy-web-app  
   - **Label**: Browse Deploy web app  
   - **Operation ID**: browse_node  
   - **Method**: GET  
   - **Relative Path**: /v1/catalog/nodes/intent%3Adeploy-web-app  
   - **Requires Authentication**: false