| name | spark-lineage |
| description | oleander-specific Spark guidance for connected OpenLineage, collect() pitfalls, and environment variable usage. |
oleander Spark Lineage
Use this skill when Spark lineage in oleander looks disconnected or when rewriting Spark jobs to preserve connected lineage.
Lineage context
Key behavior from oleander Spark/OpenLineage integrations:
collect() is a Spark action that materializes data into driver memory.- After
collect(), execution is regular Python in-memory logic, not distributed Spark DataFrame execution.
- Spark can treat "read + collect" and "write from memory" as separate jobs.
- The OpenLineage Spark integration may not connect those phases as one continuous lineage path.
Recommended lineage-safe pattern
Prefer this shape for connected lineage:
df = spark.table(...)- chain DataFrame transforms (
select, withColumn, join, aggregate)
- finalize with
df.write(...)
If collect() is required, keep it for small side-effects or reporting, not as the core bridge between read and write.
Rewrite checklist
When fixing lineage gaps:
- Find points where data leaves Spark (
collect, toPandas, driver loops).
- Move transformation logic back into DataFrame expressions whenever possible.
- Keep read-transform-write in one Spark flow.
- Ensure final writes are Spark writes (
df.write...), not Python-memory writes.
- Re-run and confirm lineage graph connectivity and Spark job boundaries.
Environment variables
Use env vars for runtime configuration, not transformation logic.
- Provide safe defaults:
os.getenv("VAR", "default")
- Validate required env vars at startup and fail early with clear errors.
- Keep env-driven behavior small and explicit (names, toggles, destinations).
Example pattern:
import os
job_name = os.getenv("NAME", "default-service")
output_catalog = os.getenv("OUTPUT_CATALOG", "oleander.sf")
In this repo, examples/print_name.py uses:
NAME with fallback default-service
