apache / apache/iceberg-python
`Table.scan(options=...)` silently ignores S3 properties for FileIO during data materialization (`to_pandas` / `to_arrow`)
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Description
### Apache Iceberg version
0.11.0 (latest release)
### Please describe the bug 🐞
**Description:**
When passing an `options` dictionary to `Table.scan(options=...)`, the properties (such as `s3.connect-timeout` or `s3.request-timeout`) are accepted by the `DataScan` object but are never propagated to the underlying `FileIO` (e.g., `PyArrowFileIO`) when actual data materialization occurs via methods like `to_pandas()` or `to_arrow()`.
Because `ArrowScan` is initialized with the `FileIO` that was created during catalog instantiation (`table.io`), any S3-specific configurations provided at the scan level are completely bypassed. This causes operations reading numerous manifest files to fall back to the AWS C++ SDK default timeouts (often 10s-30s), leading to unexpected `curlCode: 28 (Timeout was reached)` errors even when generous timeouts are explicitly requested in the scan options.
**Steps to Reproduce:**
```
# 1. Load catalog with default (or no) S3 timeout properties
from pyiceberg.catalog import load_catalog
catalog = load_catalog("my_catalog", **{
"uri": "...",
"s3.endpoint": "..."
})
table = catalog.load_table("my_namespace.my_table")
# 2. Attempt to scan with explicit S3 timeout options
scan_options = {
"s3.connect-timeout": "600.0",
"s3.request-timeout": "600.0"
}
# The options are accepted by DataScan...
scan = table.scan(options=scan_options)
# 3. ...but completely ignored during S3 I/O operations (ArrowScan)
# This may throw a timeout error if RGW/S3 latency spikes, ignoring the 600s setting above.
df = scan.to_pandas()
```
### Expected Behavior:
Properties passed via options in Table.scan() should cascade down and either update or override the table.io.properties for the duration of the scan. Specifically, s3.* configurations should be respected by the underlying FileIO (e.g., PyArrowFileIO) when downloading manifest lists or data files.
### Actual Behavior:
The options passed to Table.scan() are stored in the DataScan instance but are never passed to the ArrowScan class or the FileIO instance during to_arrow() / to_pandas().
The ArrowScan relies entirely on the unmodified self.io object originally initialized by the catalog:
```
# In pyiceberg/table/__init__.py -> DataScan.to_arrow()
return ArrowScan(
self.table_metadata,
self.io, # <--- options are missing here!
self.projection(),
self.row_filter,
self.case_sensitive,
self.limit
).to_table(self.plan_files())
```
Environment:
- PyIceberg Version: 0.11.1 (and earlier)
- PyArrow Version: 18.0.0
- Storage: Ceph S3 / Rados Gateway (RGW)
### Suggested Fix:
Ideally, DataScan should merge its options with self.io.properties and instantiate a new FileIO, or ArrowScan should be modified to accept the scan-level options and apply them dynamically to the FileSystem instance before reading files.
### Willingness to contribute
- [x] I can contribute a fix for this bug independently
- [x] I would be willing to contribute a fix for this bug with guidance from the Iceberg community
- [ ] I cannot contribute a fix for this bug at this time
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