# Host community forum with Phoenix: private documents

## Summary
Deploy a community forum built with Phoenix on Ample using the private document library 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 Phoenix: a role-to-document access model with negative tests (401 without identity, 403 for the wrong role) and a private-bucket round-trip for the allowed role (private=ok). Not separately tested: your identity integration and role assignments; treat the community forum-specific behavior as your application code.

## Representative Queries
- Host community forum with Phoenix: private documents
- Where can I host Community forum built with Phoenix?
- I need a role-to-document access model and negative authorization tests.

## 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.

## Prerequisites
- A Phoenix project that builds and starts with the documented commands (mix deps.get, MIX_ENV=prod mix compile and mix release in the builder, then the release bin script with PHX_SERVER=true on the elixir-1.18 template; PORT, DATABASE_URL and SECRET_KEY_BASE read in config/runtime.exs)
- 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**: elixir-1.18  
- **Runtime**: elixir  
- **Size**: s-1vcpu-1gb  
- **Install**: mix local.hex --force && mix local.rebar --force && MIX_ENV=prod mix deps.get --only prod  
- **Build**: MIX_ENV=prod mix compile && MIX_ENV=prod mix release --overwrite  
- **Start**: PHX_SERVER=true _build/prod/rel/$(ls _build/prod/rel | head -n 1)/bin/$(ls _build/prod/rel | head -n 1) start

## Workflow Steps
1. **Build and start**  
   mix deps.get, MIX_ENV=prod mix compile and mix release in the builder, then the release bin script with PHX_SERVER=true on the elixir-1.18 template; PORT, DATABASE_URL and SECRET_KEY_BASE read in config/runtime.exs. The server must bind 0.0.0.0 on PORT.

2. **Implement the pattern on PostgreSQL**  
   The fixture's module implements private document library: a role-to-document access model with negative tests (401 without identity, 403 for the wrong role) and a private-bucket round-trip for the allowed role (private=ok). 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/private-document-library) 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
- **App responds on its public URL**  
   - **Kind**: http_get  
   - **Path**: /  
   - **Expect**: ample canary phoenix patterns

- **Private-document-library self-test**  
   - **Kind**: http_get  
   - **Path**: /p/private-document-library  
   - **Expect**: private=ok (with ?role=owner; 401 without, 403 for viewer)

## Limitations
- Verified on the elixir-1.18 template at s-1vcpu-1gb with the example fixture; other sizes, templates and Phoenix major versions are not verified.
- The community forum itself (your identity integration and role assignments) 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
- **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
1. **Kind**: canary_run  
   - **Summary**: Phoenix pattern fixture deployed on Ample (mix deps.get, MIX_ENV=prod mix compile and mix release in the builder, then the release bin script with PHX_SERVER=true on the elixir-1.18 template; PORT, DATABASE_URL and SECRET_KEY_BASE read in config/runtime.exs); checks passed for private-document-library and configuration-secrets. Pattern proof: a role-to-document access model with negative tests (401 without identity, 403 for the wrong role) and a private-bucket round-trip for the allowed role (private=ok).  
   - **Observed At**: 2026-09-20T23:45:31Z  
   - **Implementation Revision**: 4d1511e574302f3904b75088bd4048a0975218b3-dirty (CLI 0.1.21)  
   - **Expires At**: 2027-03-19T23:45:31Z  
   - **Scope**:  
     - **Checks**: [/p/private-document-library]  
     - **Pattern**: pattern:private-document-library  
     - **Template**: elixir-1.18

2. **Kind**: canary_run  
   - **Summary**: The same Phoenix app deployed with a --release-command migration; the marker it created was readable after activation.  
   - **Observed At**: 2026-09-20T23:45:31Z  
   - **Implementation Revision**: 4d1511e574302f3904b75088bd4048a0975218b3-dirty (CLI 0.1.21)  
   - **Expires At**: 2027-03-19T23:45:31Z  
   - **Scope**:  
     - **Pattern**: pattern:private-document-library

## Last Verified At
2026-09-20T23:45:31Z

## Formats
- **HTML**: [Host community forum with Phoenix: private documents](/content/recipes/community-forum/phoenix/private-documents/index.html)
- **Markdown**: [Host community forum with Phoenix: private documents](/content/recipes/community-forum/phoenix/private-documents.md)
- **JSON**: [Host community forum with Phoenix: private documents](https://api.ample.computer/v1/catalog/recipes/page%3Arecipes%3Acommunity-forum%3Aphoenix%3Aprivate-documents)

## Next Actions
1. **Browse the catalog index**  
   - **Action ID**: browse-catalog  
   - **Operation ID**: catalog_index  
   - **Method**: GET  
   - **Relative Path**: /v1/catalog  
   - **Requires Authentication**: false  
   - **Requires Approval**: false

2. **Search published recipes by intent, stack and constraints**  
   - **Action ID**: search-recipes  
   - **Operation ID**: search_recipes  
   - **Method**: POST  
   - **Relative Path**: /v1/catalog/search  
   - **Parameters**: {"body":{"limit":5,"query":"Host community forum with Phoenix: private documents"}}  
   - **Requires Authentication**: false  
   - **Requires Approval**: false

3. **Prepare a side-effect-free deployment plan for an authorized project**  
   - **Action ID**: plan:page:recipes:community-forum:phoenix:private-documents  
   - **Operation ID**: plan_deployment  
   - **Method**: POST  
   - **Relative Path**: /v1/catalog/plan  
   - **Parameters**: {"body":{"inputs":{},"projectId":"","recipeId":"page:recipes:community-forum:phoenix:private-documents","recipeRevision":"r1"}}  
   - **Requires Authentication**: true  
   - **Requires Approval**: false

4. **Read the existing agent authentication setup**  
   - **Action ID**: auth-setup  
   - **Operation ID**: existing_auth_setup  
   - **Method**: GET  
   - **Relative Path**: /mcp/setup  
   - **Requires Authentication**: false  
   - **Requires Approval**: false

5. **Browse Community forum**  
   - **Action ID**: browse:workload:community-forum  
   - **Operation ID**: browse_node  
   - **Method**: GET  
   - **Relative Path**: /v1/catalog/nodes/workload%3Acommunity-forum  
   - **Parameters**: {"nodeId":"workload:community-forum"}  
   - **Requires Authentication**: false  
   - **Requires Approval**: false

6. **Browse Phoenix**  
   - **Action ID**: browse:stack:framework-phoenix  
   - **Operation ID**: browse_node  
   - **Method**: GET  
   - **Relative Path**: /v1/catalog/nodes/stack%3Aframework-phoenix  
   - **Parameters**: {"nodeId":"stack:framework-phoenix"}  
   - **Requires Authentication**: false  
   - **Requires Approval**: false

7. **Browse Private document library**  
   - **Action ID**: browse:pattern:private-document-library  
   - **Operation ID**: browse_node  
   - **Method**: GET  
   - **Relative Path**: /v1/catalog/nodes/pattern%3Aprivate-document-library  
   - **Parameters**: {"nodeId":"pattern:private-document-library"}  
   - **Requires Authentication**: false  
   - **Requires Approval**: false

8. **Browse Deploy web app**  
   - **Action ID**: browse:intent:deploy-web-app  
   - **Operation ID**: browse_node  
   - **Method**: GET  
   - **Relative Path**: /v1/catalog/nodes/intent%3Adeploy-web-app  
   - **Parameters**: {"nodeId":"intent:deploy-web-app"}  
   - **Requires Authentication**: false  
   - **Requires Approval**: false