dd-l1-vienna-gpkg-manifest
Map (reference ← swipe → agent)
0:00
Inherited a GPKG (vienna_planning) from a colleague who retired last week. Before I commit to scripting against it I need a one-page manifest so I can see what's in there and decide which layers actually feed next month's councillor briefing. Catalog the contents and give me one record per layer. Output manifest.json — a JSON list of these records.
Each record in the list must be a JSON object with exactly five keys: `layer_name` as a string, `crs` as a string in `EPSG:NNNN` form, `geometry_type` as a string matching the layer's native type (e.g. `Point`, `LineString`, `Polygon`, `MultiPolygon`), `feature_count` as an integer, and `bbox` as a list of four numbers `[xmin, ymin, xmax, ymax]` in the layer's native CRS.
0:00
System info
{
"adapter": "openrouter",
"model": "deepseek/deepseek-v4-flash",
"base_url": "https://openrouter.ai/api/v1"
}
0:06
Let me start by exploring the GPKG file to understand its contents, then write a script to catalog everything.
0:06
Bash
ls -lh /work/vienna_planning.gpkg 2>/dev/null || ls -lh /work/
-rw-r--r-- 1 agent agent 512K Jun 18 13:57 /work/vienna_planning.gpkg
0:10
Let me first explore the GPKG to see what layers it contains.
0:10
Bash
python3 -c "
python3 -c "
import geopandas as gpd
# List layers
layers = gpd.list_layers('/work/vienna_planning.gpkg')
print(layers)
"
name geometry_type 0 districts Polygon 1 parks MultiPolygon 2 waterbodies Polygon 3 schools Point 4 cafes Point 5 supermarkets Point 6 cycleway_segments LineString
0:19
Good, I can see there are 7 layers. Let me gather info for each one: CRS, feature count, and bounding box.
0:19
Bash
python3 -c "
python3 -c "
import geopandas as gpd
import json
layers = ['districts', 'parks', 'waterbodies', 'schools', 'cafes', 'supermarkets', 'cycleway_segments']
results = []
for lyr in layers:
gdf = gpd.read_file('/work/vienna_planning.gpkg', layer=lyr)
crs = gdf.crs
# Convert to EPSG:XXXX string
if crs is None:
crs_str = 'None'
else:
crs_str = crs.to_authority()
if crs_str:
crs_str = f'{crs_str[0]}:{crs_str[1]}'
else:
crs_str = str(crs)
geom_type = gdf.geometry.geom_type.iloc[0]
# For Multi* types, geopandas might give 'MultiPolygon' etc. — keep as is
feature_count = len(gdf)
# Total bounds across all features
bbox = [float(gdf.total_bounds[0]), float(gdf.total_bounds[1]),
float(gdf.total_bounds[2]), float(gdf.total_bounds[3])]
results.append({
'layer_name': lyr,
'crs': crs_str,
'geometry_type': geom_type,
'feature_count': feature_count,
'bbox': bbox
})
print(json.dumps(results, indent=2))
"
[
{
"layer_name": "districts",
"crs": "EPSG:31287",
"geometry_type": "Polygon",
"feature_count": 22,
"bbox": [
623867.3888224852,
481236.5836125494,
626371.3079994549,
484403.7315526943
]
},
{
"layer_name": "parks",
"crs": "EPSG:31287",
"geometry_type": "MultiPolygon",
"feature_count": 119,
"bbox": [
623851.990195953,
481200.6674012489,
626620.9438865517,
485539.3479671855
]
},
{
"layer_name": "waterbodies",
"crs": "EPSG:31287",
"geometry_type": "Polygon",
"feature_count": 33,
"bbox": [
624288.8521056126,
481236.66320640914,
626747.8611584986,
484132.0212685799
]
},
{
"layer_name": "schools",
"crs": "EPSG:31287",
"geometry_type": "Point",
"feature_count": 40,
"bbox": [
624000.002417057,
481214.73871311604,
626259.5421406503,
484178.87865010765
]
},
{
"layer_name": "cafes",
"crs": "EPSG:31287",
"geometry_type": "Point",
"feature_count": 392,
"bbox": [
623796.529863561,
481107.2540129812,
626399.5618121764,
484498.9209005649
]
},
{
"layer_name": "supermarkets",
"crs": "EPSG:31287",
"geometry_type": "Point",
"feature_count": 87,
"bbox": [
623794.0549950565,
481148.38703723426,
626392.6164786755,
484489.91954147833
]
},
{
"layer_name": "cycleway_segments",
"crs": "EPSG:31287",
"geometry_type": "LineString",
"feature_count": 271,
"bbox": [
623787.4932131292,
481134.9325878215,
626619.1631922598,
485245.6624853243
]
}
]
0:27
The results look good. All layers share EPSG:31287 (MGI / Austria GK Central). The bbox values are in metric coordinates (6-digit range, as expected for a local Austrian projection). Let me write this out as manifest.json.
0:27
Write
/work/manifest.json
content · 51 lines · json
[
{
"layer_name": "districts",
"crs": "EPSG:31287",
"geometry_type": "Polygon",
"feature_count": 22,
"bbox": [623867.3888224852, 481236.5836125494, 626371.3079994549, 484403.7315526943]
},
{
"layer_name": "parks",
"crs": "EPSG:31287",
"geometry_type": "MultiPolygon",
"feature_count": 119,
"bbox": [623851.990195953, 481200.6674012489, 626620.9438865517, 485539.3479671855]
},
{
"layer_name": "waterbodies",
"crs": "EPSG:31287",
"geometry_type": "Polygon",
"feature_count": 33,
"bbox": [624288.8521056126, 481236.66320640914, 626747.8611584986, 484132.0212685799]
},
{
"layer_name": "schools",
"crs": "EPSG:31287",
"geometry_type": "Point",
"feature_count": 40,
"bbox": [624000.002417057, 481214.73871311604, 626259.5421406503, 484178.87865010765]
},
{
"layer_name": "cafes",
"crs": "EPSG:31287",
"geometry_type": "Point",
"feature_count": 392,
"bbox": [623796.529863561, 481107.2540129812, 626399.5618121764, 484498.9209005649]
},
{
"layer_name": "supermarkets",
"crs": "EPSG:31287",
"geometry_type": "Point",
"feature_count": 87,
"bbox": [623794.0549950565, 481148.38703723426, 626392.6164786755, 484489.91954147833]
},
{
"layer_name": "cycleway_segments",
"crs": "EPSG:31287",
"geometry_type": "LineString",
"feature_count": 271,
"bbox": [623787.4932131292, 481134.9325878215, 626619.1631922598, 485245.6624853243]
}
]
Wrote /work/manifest.json (1489 chars).
0:41
Let me verify the manifest.json is valid JSON and the bbox values look correct by re-reading the file and also sanity-checking the coordinates.
The CRS is EPSG:31287 (MGI / Austria GK Central). For Vienna, coordinates in this CRS should be around:
- Easting: ~620,000 to ~627,000
- Northing: ~480,000 to ~485,000
These look reasonable for Vienna in EPSG:31287. Let me double-check the bbox for cafes - actually the min y from the output was 481107.2540129812 but in my Python output it was 481214.73871311604... Wait, let me check.
Looking back at the Python output:
cafes bbox was: [623796.529863561, 481107.2540129812, 626399.5618121764, 484498.9209005649]
But wait, in the Python script output I see cafes:
"bbox": [
623796.529863561,
481107.2540129812, <-- Wait, the original Python output had 481214.73871311604?
...
Actually looking more carefully at the original Python output:
```
"cafes": {
...
"bbox": [
623796.529863561,
481107.2540129812,
...
```
Hmm wait, but looking at the python output lines more carefully, the output from the script was:
```
{
"layer_name": "cafes",
...
"bbox": [
623796.529863561,
481107.2540129812,
626399.5618121764,
484498.9209005649
]
},
```
This seems off - I had written 481107 in the file, but the original Python output showed something around 481200+ for the schools layer. Let me re-run to double check the exact values.
0:41
Bash
python3 -c "
python3 -c "
import geopandas as gpd
gdf = gpd.read_file('/work/vienna_planning.gpkg', layer='cafes')
print('cafes bounds:', list(gdf.total_bounds))
"
cafes bounds: [np.float64(623796.529863561), np.float64(481107.2540129812), np.float64(626399.5618121764), np.float64(484498.9209005649)]
0:51
Everything checks out. Let me verify the manifest.json is valid JSON and has the correct structure.
0:51
Bash
python3 -c "
python3 -c "
import json
with open('/work/manifest.json') as f:
data = json.load(f)
print(f'Records: {len(data)}')
for rec in data:
assert set(rec.keys()) == {'layer_name', 'crs', 'geometry_type', 'feature_count', 'bbox'}
assert isinstance(rec['layer_name'], str)
assert isinstance(rec['crs'], str)
assert isinstance(rec['geometry_type'], str)
assert isinstance(rec['feature_count'], int)
assert isinstance(rec['bbox'], list) and len(rec['bbox']) == 4
print(f' {rec[\"layer_name\"]:20s} {rec[\"crs\"]:12s} {rec[\"geometry_type\"]:15s} {rec[\"feature_count\"]:4d} BBox: {rec[\"bbox\"]}')
print('All good.')
"
Records: 7 districts EPSG:31287 Polygon 22 BBox: [623867.3888224852, 481236.5836125494, 626371.3079994549, 484403.7315526943] parks EPSG:31287 MultiPolygon 119 BBox: [623851.990195953, 481200.6674012489, 626620.9438865517, 485539.3479671855] waterbodies EPSG:31287 Polygon 33 BBox: [624288.8521056126, 481236.66320640914, 626747.8611584986, 484132.0212685799] schools EPSG:31287 Point 40 BBox: [624000.002417057, 481214.73871311604, 626259.5421406503, 484178.87865010765] cafes EPSG:31287 Point 392 BBox: [623796.529863561, 481107.2540129812, 626399.5618121764, 484498.9209005649] supermarkets EPSG:31287 Point 87 BBox: [623794.0549950565, 481148.38703723426, 626392.6164786755, 484489.91954147833] cycleway_segments EPSG:31287 LineString 271 BBox: [623787.4932131292, 481134.9325878215, 626619.1631922598, 485245.6624853243] All good.
0:55
Everything checks out. Let me verify the file exists on disk.
0:55
Bash
ls -lh /work/manifest.json
-rw-r--r-- 1 agent agent 1.5K Jun 18 13:58 /work/manifest.json
1:01
Everything checks out. Let me summarize what was produced.
1:01