page:recipes:mcp server:flask:artifact storage
Host MCP Server with Flask: Stored Input and Output Artifacts
Summary
Deploy a mcp server built with Flask 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 Flask: 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 mcp server-specific behavior as your application code.
Representative Queries
- Host mcp server with Flask: stored input and output artifacts
- Where can I host MCP server built with Flask?
- 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
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.
- More Info: Compute
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.
- More Info: Postgres
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.
- More Info: S3
Prerequisites
- A Flask project that builds and starts with the documented commands (pip install into .ample/python from requirements.txt, then waitress from app.py reading PORT on the python-3.12 template)
- A PostgreSQL driver reading DATABASE_URL at runtime (auto-provisioned when omitted, or supplied with --env)
- A bucket from
ample bucket createwith its credentials passed as encrypted S3_* environment variables - An Ample account token with servers:write, databases:read, buckets:read
Tested Configuration
- Template: python-3.12
- Runtime: python
- Size: s-1vcpu-1gb
- Install: python3 -m pip install --target .ample/python -r requirements.txt
- Start: PYTHONPATH=.ample/python:${PYTHONPATH:-} python3 app.py
Workflow Steps
Build and start
pip install into .ample/python from requirements.txt, then waitress from app.py reading PORT on the python-3.12 template. The server must bind 0.0.0.0 on PORT.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.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.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.ample deploy . --name <name> --public --start "python3 app.py" --env S3_ENDPOINT=<endpoint> --env S3_REGION=<region> --env S3_BUCKET=<bucket> --env S3_ACCESS_KEY_ID=<access_key> --env S3_SECRET_ACCESS_KEY=<secret_key>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 readample logs --kind buildthen--kind runtime.ample logs --kind build
Success Checks
App Responds
- Kind: http_get
- Path: /
- Expect: ample canary flask patterns
Generated Downloads Self-test
- Kind: http_get
- Path: /p/generated-downloads
- Expect: export=ok rows=3 (with ?token=...; 401 without)
Limitations
- Verified on the python-3.12 template at s-1vcpu-1gb with the example fixture; other sizes, templates and Flask major versions are not verified.
- The mcp server 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
- Basis: size prices from pricing.toml (loaded by the API) at build revision 1ac5595375130d45290090e82ed0f554ccd45405-dirty
Cost Components
App server
- Size: s-1vcpu-1gb
- Quantity: 1.0
- Monthly Amount: 5.0
Managed PostgreSQL database
- Size: s-1vcpu-1gb
- Quantity: 1.0
- Monthly Amount: 5.0
Additional 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
- Canary Run: Flask pattern fixture deployed on Ample (pip install into .ample/python from requirements.txt, then waitress from app.py reading PORT on the python-3.12 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).