Band object is not iterable
MaxDragonheart opened this issue · comments
Hi guys! Probably this is not a bug but my misunderstanding about how is possible to create the assets.
Whit the function below, I create a dictionary with all bands of Sentinel 2 platform:
def create_band() -> Dict:
"""Create bands for STAC Catalog.
Returns:
List
"""
bands = {}
for key, value in SENTINEL2_BANDS.items():
name = value["name"]
description = value["description"]
common_name = key
bands[name] = Band.create(
name=name,
description=description,
common_name=common_name,
)
return bands
SENTINEL2_BANDS is a simple dictionary with values useful for me:
SENTINEL2_BANDS = {
'coastal': {
'name': 'B01',
'wavelength': {
'min': 412,
'max': 456,
'central': 442.45,
'unit': 'nanometers'
},
'resolution': {
'size': 60,
'unit': 'meter',
},
'description': 'Coastal aerosol',
},
'blue': {
'name': 'B02',
'wavelength': {
'min': 456,
'max': 533,
'central': 492.25,
'unit': 'nanometers'
},
'resolution': {
'size': 10,
'unit': 'meter',
},
'description': 'Visible blue',
},
'green': {
'name': 'B03',
'wavelength': {
'min': 538,
'max': 583,
'central': 559.4,
'unit': 'nanometers'
},
'resolution': {
'size': 10,
'unit': 'meter',
},
'description': 'Visible green',
},
'red': {
'name': 'B04',
'wavelength': {
'min': 646,
'max': 684,
'central': 664.75,
'unit': 'nanometers'
},
'resolution': {
'size': 10,
'unit': 'meter',
},
'description': 'Visible red',
},
'rededge1': {
'name': 'B05',
'wavelength': {
'min': 695,
'max': 714,
'central': 703.95,
'unit': 'nanometers'
},
'resolution': {
'size': 20,
'unit': 'meter',
},
'description': 'Vegetation classification red edge',
},
'rededge2': {
'name': 'B06',
'wavelength': {
'min': 731,
'max': 749,
'central': 739.8,
'unit': 'nanometers'
},
'resolution': {
'size': 20,
'unit': 'meter',
},
'description': 'Vegetation classification red edge',
},
'rededge3': {
'name': 'B07',
'wavelength': {
'min': 769,
'max': 797,
'central': 781.25,
'unit': 'nanometers'
},
'resolution': {
'size': 20,
'unit': 'meter',
},
'description': 'Vegetation classification red edge',
},
'nir': {
'name': 'B08',
'wavelength': {
'min': 760,
'max': 907,
'central': 832.85,
'unit': 'nanometers'
},
'resolution': {
'size': 10,
'unit': 'meter',
},
'description': 'Near infrared',
},
'nir08': {
'name': 'B8A',
'wavelength': {
'min': 837,
'max': 881,
'central': 864.35,
'unit': 'nanometers'
},
'resolution': {
'size': 20,
'unit': 'meter',
},
'description': 'Vegetation classification red edge',
},
'nir09': {
'name': 'B09',
'wavelength': {
'min': 932,
'max': 958,
'central': 944.15,
'unit': 'nanometers'
},
'resolution': {
'size': 60,
'unit': 'meter',
},
'description': 'Water vapor',
},
'cirrus': {
'name': 'B10',
'wavelength': {
'min': 1337,
'max': 1412,
'central': 1375.2,
'unit': 'nanometers'
},
'resolution': {
'size': 60,
'unit': 'meter',
},
'description': 'Used for atmospheric correction only, not present in L2A products',
},
'swir16': {
'name': 'B11',
'wavelength': {
'min': 1539,
'max': 1682,
'central': 1612.05,
'unit': 'nanometers'
},
'resolution': {
'size': 20,
'unit': 'meter',
},
'description': 'Short-wave infrared, snow/ice/cloud classification',
},
'swir22': {
'name': 'B12',
'wavelength': {
'min': 2078,
'max': 2320,
'central': 2194.05,
'unit': 'nanometers'
},
'resolution': {
'size': 20,
'unit': 'meter',
},
'description': 'Short-wave infrared, snow/ice/cloud classification',
},
'aot': {
'name': 'AOT',
'wavelength': None,
'resolution': {
'size': 10,
'unit': 'meter',
},
'description': 'Aerosol optical thickness',
},
'scl': {
'name': 'SCL',
'wavelength': None,
'resolution': {
'size': 20,
'unit': 'meter',
},
'description': 'Scene classfication map',
},
'wvp': {
'name': 'WVP',
'wavelength': None,
'resolution': {
'size': 20,
'unit': 'meter',
},
'description': 'Water vapour',
},
'tci': {
'name': 'visual',
'wavelength': None,
'resolution': {
'size': 20,
'unit': 'meter',
},
'description': 'True color image; B04 (red), B03 (green), B02 (blue)',
},
}
Later, I try to create the asset from each band. E.g. using B04:
# Create asset
asset = pystac.Asset(
href=band_path,
title=band_name,
description=band_description
)
print(asset.to_dict())
{'href': './S2B_MSIL2A_20230601T094549_R079_T33TVF_20230601T163334/T33TVF_20230601T094549_B04_10m.tif', 'title': 'B04', 'description': 'Band description.'}
# Get STAC band information
band_info = create_band()[band_name]
print(band_info)
<Band name=B04>
# Add Electro-Optical Extension
asset_eo_ext = EOExtension.ext(asset)
print(asset_eo_ext)
<AssetEOExtension Asset href=./S2B_MSIL2A_20230601T094549_R079_T33TVF_20230601T163334/T33TVF_20230601T094549_B04_10m.tif>
Problems come when I try to apply band_info to asset_eo_ext:
asset_eo_ext.apply(bands=band_info)
Here the error message:
../../eo_drako/stac/stac.py:145: in sentinel2_band
asset_eo_ext.apply(bands=band_info)
/home/max/.cache/pypoetry/virtualenvs/eo-drako-nSMVjevg-py3.10/lib/python3.10/site-packages/pystac/extensions/eo.py:311: in apply
self.bands = bands
/home/max/.cache/pypoetry/virtualenvs/eo-drako-nSMVjevg-py3.10/lib/python3.10/site-packages/pystac/extensions/eo.py:325: in bands
BANDS_PROP, map_opt(lambda bands: [b.to_dict() for b in bands], v)
/home/max/.cache/pypoetry/virtualenvs/eo-drako-nSMVjevg-py3.10/lib/python3.10/site-packages/pystac/utils.py:435: in map_opt
return v if v is None else fn(v)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
bands = <Band name=B04>
> BANDS_PROP, map_opt(lambda bands: [b.to_dict() for b in bands], v)
)
E TypeError: 'Band' object is not iterable
/home/max/.cache/pypoetry/virtualenvs/eo-drako-nSMVjevg-py3.10/lib/python3.10/site-packages/pystac/extensions/eo.py:325: TypeError
What I'm doing wrong?
I'm using Python 3.10 with pystac 1.7.3
In this line:
asset_eo_ext.apply(bands=band_info)bands should be a list[Band] -- in your case, it's just a Band. If your asset only has one band, all you need to do is wrap your band_info in a list, e.g.:
asset_eo_ext.apply(bands=[band_info])Closing as answered. @MaxDragonheart please re-open if that resolution is incorrect.
Sorry for the late response. Thank for your support, this asset_eo_ext.apply(bands=[band_info]) solved the trouble 😄