page:recipes:ai chat application:nestjs:artifact storage

Host AI Chat Application with NestJS: Stored Input and Output Artifacts

Summary

Deploy an AI chat application built with NestJS 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, and a private S3-compatible bucket holds objects with credentials delivered as encrypted environment variables. Verified on NestJS: 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).

Representative Queries

• Host AI chat application with NestJS: stored input and output artifacts
• Where can I host an AI chat application built with NestJS?
• I need an input/output artifact contract, object metadata, and access boundaries.

Resource Requirements

• primitive:compute
• primitive:postgres
• primitive:s3-compatible-object-storage

Infrastructure Requirements

1. Compute
   Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; sizes are the priced VM sizes.
   (Verified)

2. Postgres
   Managed PostgreSQL 16 runs in its own microVM and is auto-provisioned when an app needs a database and no DATABASE_URL is supplied.
   (Verified)

3. S3-compatible Object Storage
   Buckets are S3-compatible with issued credentials; PutObject and GetObject are verified by canary. Other S3 operations are not verified.
   (Verified)

Prerequisites

• A NestJS project that builds and starts with the documented commands (npm install, nest build (TypeScript) then node dist/main.js 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

Workflow Steps

1. Build and Start
   npm install, nest build (TypeScript) then node dist/main.js 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

Success Checks

• The app responds on its public URL (/). Expected output: ample canary nestjs patterns
• Generated-downloads self-test at path /p/generated-downloads. Expected output: 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 NestJS major versions are not verified.
• The AI chat application itself (your export formats, retention policy, and entitlement model) is application code and was not separately tested; the pattern checks are what was verified.

Cost Estimate

• Currency: USD
• Monthly Amount: 10.0
• 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

• NestJS pattern fixture deployed on Ample (npm install, nest build (TypeScript) then node dist/main.js on the node-22 template); checks passed for generated-downloads and configuration-secrets.
• The same NestJS app deployed with a --release-command migration; the marker it created was readable after activation.

Next Actions

• Browse the catalog index

  • Action ID: browse-catalog
  • Method: GET
  • Relative Path: /v1/catalog
  • Requires Authentication: No

• Search published recipes by intent, stack, and constraints

  • Action ID: search-recipes
  • Method: POST
  • Relative Path: /v1/catalog/search
  • Requires Authentication: No

• Prepare a side-effect-free deployment plan for an authorized project

  • Action ID: plan:page:recipes:ai-chat-application:nestjs:artifact-storage
  • Method: POST
  • Relative Path: /v1/catalog/plan
  • Requires Authentication: Yes

• Read the existing agent authentication setup

  • Action ID: auth-setup
  • Method: GET
  • Relative Path: /mcp/setup
  • Requires Authentication: No

• Browse AI chat application

  • Action ID: browse:workload:ai-chat-application
  • Method: GET
  • Relative Path: /v1/catalog/nodes/workload%3Aai-chat-application
  • Requires Authentication: No