Case study 04

Industrial IoT data pipeline

Solar telemetry

Transporting irregular device telemetry from Raspberry Pi data loggers into a remotely queryable cloud store.

Role
Software Developer
Period
Jun 2023 — Nov 2023
Repository
Data-Cloud-Integration- ↗
183
fields in the exercised sample payload
Python 3.11
Lambda parser runtime
200
documented successful API response
PythonAWS API GatewayVTLAWS LambdaMongoDBRaspberry Pi
01 — Business problem

What had to change

Industrial solar loggers emitted large form-encoded payloads containing CSV headers and readings rather than application-ready JSON. The data needed to cross a public API boundary, be transformed safely, and become useful for remote monitoring.

This was an early applied cloud project: the goal was a working ingestion path, with security and production hardening still explicitly incomplete in the repository documentation.

02 — Engineering decisions

Decisions that shaped the system

Each choice connects a business constraint to an implementation boundary and retained evidence.

01

Transform at the gateway

Used a Velocity Template Language mapping to convert application/x-www-form-urlencoded input into the event shape expected by Lambda.

Evidence · The README documents the original payload format, mapping boundary, headers, status codes, and API flow.
02

Preserve signal names

Parsed the first CSV row as headers and zipped later values into a nested values object keyed by the original telemetry names.

Evidence · The repository's Lambda example shows header extraction and MongoDB document construction.
03

Package the missing runtime

Provided PyMongo through a Lambda layer and kept database connectivity inside the short-lived function execution path.

Evidence · The repository explains the external library bundle and MongoDB connection lifecycle.
03 — System model

How the pieces connect

  1. 01Raspberry Pi logger
  2. 02API Gateway + VTL
  3. 03Lambda parser
  4. 04MongoDB collection
  5. 05Remote generation views
04 — Outcomes and boundaries

What the work produced

The pipeline accepted device readings through API Gateway, transformed them, inserted structured timestamped records into MongoDB, and made remote generation data available for visualization work.

The case study also preserves the honest limitation: endpoint secrecy was not a security model, and input validation, authentication, and rate controls needed a proper production pass.

183
fields in the exercised sample payload
Python 3.11
Lambda parser runtime
200
documented successful API response

Evidence basis

What supports this story

Next case studyFAMS ERP