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name: vector-io description: "Guides Fiona Python workflows for reading, writing, appending, inspecting, and safely round-tripping vector datasets, features, schemas, layers, memory files, and local virtual files." disable-model-invocation: true metadata: disco-role: operating license: BSD 3-Clause

Fiona vector I/O

Use this route when the task is about Fiona's Python API for vector data: open a file, stream features, inspect metadata, create or append a layer, validate a schema, use Feature/Geometry/Properties, or work with bytes and local archive paths. Fiona is a GDAL/OGR-backed feature I/O library; it is not a geometry-analysis or CRS-transformation engine.

Route

1. Read API reference for signatures and object behavior.
2. Read workflows for read, write, append, conversion, and memory-file recipes.
3. Read data model and schema when creating a layer or diagnosing field/geometry mismatches.
4. Read troubleshooting before changing a driver, CRS, encoding, or schema after an error.
5. For CRS construction or coordinate transformation, continue to crs-transform. For GDAL configuration, driver discovery, or cloud sessions, use environment-cloud. For shell pipelines, use cli.

Core decision points

• Reading normally needs only a dataset path and optional layer; writing needs a driver, schema, and usually a CRS.
• Prefer with fiona.open(...) so external GDAL resources are closed even when feature processing raises.
• Use src.profile as a starting point for a compatible output, then change driver, schema, layer, or CRS deliberately and validate the result.
• Treat a Collection as a stream. Iterating consumes the current cursor; reopen it instead of assuming seeking to the beginning is supported.
• Use MemoryFile for bounded byte-backed or temporary datasets. Use a normal path when the result must persist beyond the process.
• Use include_fields or ignore_fields, but never both in one open call.

The generated references contain the operational detail; they are designed to work when the original Fiona checkout is unavailable.