ATLAS / SYSTEM NOTES
Atlas · System Architecture
Explain modules, request paths and data boundaries with a readable system map.
The system at a glance
Example: the fictional Atlas document service. Connections show calls and data access, not a production deployment.
Relations
- Request: Reader / Web → Entry / API
- Verify identity: Entry / API → Identity & access
- Allowed: Identity & access → Content service
- Read first: Content service → Read cache
- Miss / write: Content service → Document database
- Media reference: Content service → Media storage
How a document is opened
01
01 · Check access
The API checks the session and document permissions first. Unauthorized requests stop here so private content never reaches a shared cache.
02
02 · Read a fixed version
The content service checks the version cache. On a miss, it reads the database and caches only results that may be safely reused.
03
03 · Resolve media references
Documents store resource identifiers. The media service resolves them within the access boundary. Content and media permissions must agree.
04
04 · Respond and observe
Record the request ID, version and elapsed time. Keep full document contents, access tokens and user input out of logs.
Module contracts
| Module | Input | Output | Boundary |
|---|---|---|---|
| Content service | Document ID and permissions | Fixed-version content | Never bypass authorization |
| Media storage | Resource ID | Resource bytes | Do not trust external URLs |
| API entry | Path and session | Request context | No business-data persistence |
| Cache layer | Versioned key | Public or authorized result | No cross-user private cache |
Make failure paths explicit
01
Invalid identity
Return an identity error at the API boundary without querying the document database.
02
Storage unavailable
Return a clear error with a request ID. Do not cache an error as document content.
Adapting this to a real project
Replace the modules with real directories, entry functions and deployment units. Attach a file path, symbol and repository version to each important call. Mark unverified connections and trace a normal request, an access denial and a cache miss.
Using this template
01
Prepare your materials
Repository and version; Entry points; Configuration and call evidence
02
Keep and adapt
Preserve the logical relationships and data bindings. Adapt the sections and visual design to your readers, brand and actual materials.
Brands, projects, interviews and operating data in this template are fictional examples. They do not represent customers, research findings or investment advice. Preview forms do not collect or save answers.