csv imports.md
Host project tracker with ASP.NET Core: CSV imports
Summary
Deploy a project tracker built with ASP.NET Core on Ample using the bulk import staging 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 ASP.NET Core: a CSV staged as an object, row-level validation with per-row errors recorded, and a restart-safe import keyed by import id (imported=2 rejected=1 restart=ok). Not separately tested: your import format, mapping and conflict rules; treat the project tracker-specific behavior as your application code.
Infrastructure requirements
- Compute: verified (Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; sizes are the priced VM sizes.)
- Postgres: verified (Managed PostgreSQL 16 runs in its own microVM and is auto-provisioned when an app needs a database and no DATABASE_URL is supplied.)
- S3-compatible object storage: verified (Buckets are S3-compatible with issued credentials; PutObject and GetObject are verified by canary. Other S3 operations are not verified.)
Prerequisites
- A ASP.NET Core project that builds and starts with the documented commands (dotnet publish -c Release -o out in the builder, then dotnet
.dll on the dotnet-10 template with ASPNETCORE_URLS bound to PORT) - 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
Exact tested configuration
- template:
dotnet-10 - runtime:
dotnet - size:
s-1vcpu-1gb - build:
dotnet publish -c Release -o out - start:
ASPNETCORE_URLS=http://0.0.0.0:$PORT dotnet out/$(basename $(ls out/*.runtimeconfig.json | head -n 1) .runtimeconfig.json).dll
Steps
Build and start. dotnet publish -c Release -o out in the builder, then dotnet
.dll on the dotnet-10 template with ASPNETCORE_URLS bound to PORT. The server must bind 0.0.0.0 on PORT. Implement the pattern on PostgreSQL. The fixture's module implements bulk import staging: a CSV staged as an object, row-level validation with per-row errors recorded, and a restart-safe import keyed by import id (imported=2 rejected=1 restart=ok). 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 <app-name> --public --env S3_ENDPOINT=... --env S3_REGION=... --env S3_BUCKET=... --env S3_ACCESS_KEY_ID=... --env S3_SECRET_ACCESS_KEY=...Verify. Fetch the live URL and the pattern self-test route(s) (/p/bulk-import-staging) from the example; then run your own checks. On failure read
ample logs <deployment_id> --kind buildthen--kind runtime.ample logs <deployment_id> --kind build
Tested examples
- ASP.NET Core pattern fixture (tests/deploy-canaries/asp-net-core-patterns): Multi-pattern ASP.NET Core app whose bulk import staging module was checked live; the module is under tests/deploy-canaries/_pattern-modules.
Success checks
- app responds on its public URL (
/on the live URL, expect ample canary asp net core patterns) - bulk-import-staging self-test (
/p/bulk-import-stagingon the live URL, expect imported=2 rejected=1 restart=ok)
Limitations
- Verified on the dotnet-10 template at s-1vcpu-1gb with the example fixture; other sizes, templates and ASP.NET Core major versions are not verified.
- The project tracker itself (your import format, mapping and conflict rules) 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 verified.
Cost estimate
Estimated 10.00 USD per month (size prices from pricing.toml at build revision a1b8c38919e59cd035ebabaced73cf84ece24371).
- app server x1
s-1vcpu-1gb: 5.00 USD - managed PostgreSQL database x1
s-1vcpu-1gb: 5.00 USD
Always-on monthly price of the tested sizes; apps and databases auto-pause when idle. Buckets are allocation-priced per quota and not included.
Verification evidence
- canary_run on 2026-09-21T01:15:54Z at revision
50dbac567d2c5cc8e55e6c748a646be0025d9cfb-dirty (CLI 0.1.21): ASP.NET Core pattern fixture deployed on Ample (dotnet publish -c Release -o out in the builder, then dotnet.dll on the dotnet-10 template with ASPNETCORE_URLS bound to PORT); checks passed for bulk-import-staging and configuration-secrets. Pattern proof: a CSV staged as an object, row-level validation with per-row errors recorded, and a restart-safe import keyed by import id (imported=2 rejected=1 restart=ok). (expires 2027-03-20T01:15:54Z) - canary_run on 2026-09-20T23:34:47Z at revision
4d1511e574302f3904b75088bd4048a0975218b3-dirty (CLI 0.1.21): The same ASP.NET Core app deployed with a --release-command migration; the marker it created was readable after activation. (expires 2027-03-19T23:34:47Z)
Last verified: 2026-09-21T01:15:54Z
Execution binding
MCP tool ample_deploy (registry mcp:ample_deploy), schema hash 876465fce906da0c observed 2026-09-21T03:19:59.461917+00:00 at revision 49962bcade4f, binding state current, required scopes: servers:write, databases:read, buckets:read.