TRACT runs two rounds of validation on every GeoJSON file:
• File Check (static validation) — run immediately when you upload the file and validate GeoJSON format, geometry type, coordinate ranges, and NodeID formatting.
• System Check (second-stage validation) — run after static validation passes and verify that referenced NodeIDs exist in Master Data, along with additional geometry and business rules.
GeoJSON errors are different from Master Data and Traceability errors. They are geometry issues that typically cannot be fixed by editing a spreadsheet.
To view and correct affected polygons, you will need QGIS. We also recommend installing the TRACT Geolocation Formatter plugin.
The plugin works with both QGIS 3.x and QGIS 4 and helps you prepare and validate geolocation data before uploading to TRACT.
Before you upload: what TRACT checks
Every GeoJSON file must:
• Be in valid .geojson format
• Contain a NodeID property for every feature
• Reference NodeIDs that exist in Master Data
• Have valid polygon geometry — closed rings, no self-intersections, no duplicate vertices, and no holes
1. Boundary Has Self-Intersections
Occurs during: File Check
Occurs during: Static Validation
The boundary of one or more polygons crosses itself. The edges of the shape intersect at a point other than a vertex, making the geometry invalid.
What it looks like
A figure-eight or bow-tie shape where the polygon outline crosses over itself.
How to fix it
• Open the file in QGIS with the TRACT Geolocation Formatter plugin
• The plugin reports the exact longitude and latitude of the self-intersection point
• Use QGIS's coordinate widget to navigate directly to the location and fix the geometry
2. Missing NodeID Property
Occurs during: File Check
Every feature in your GeoJSON file must include a NodeID property. If this property is missing, TRACT cannot identify which farm or location the geometry belongs to.
How to fix it
• Open your GeoJSON file in QGIS and check the attribute table for each feature
• Add the NodeID field to all affected features
• Ensure each NodeID value matches the corresponding record in Master Data
3. NodeID Not Found in Master Data
Occurs during: System Check
The NodeID value exists in the GeoJSON file but does not match any record in your uploaded Master Data.
TRACT cannot attach geometry to a location that does not exist in the system.
How to fix it
• Confirm the NodeID exists in Master Data
• Check for typos, extra spaces, or formatting differences
• Upload or correct the Master Data record before re-uploading the GeoJSON file
• Copy NodeIDs directly from Master Data whenever possible
4. Duplicate Vertices Detected and Automatically Fixed
Occurs during: File Check
TRACT automatically removes consecutive duplicate vertices during upload. Uploads are no longer rejected for this issue.
For full details, see the Auto-removal of Duplicate Vertices article.
What this means
Duplicate vertices occur when the same coordinate appears multiple times consecutively in a polygon ring.
TRACT detects and removes these duplicates automatically before saving your data.
How to fix it
No action is required.
5. Polygon Ring Has Too Few Points or Unique Coordinates
Occurs during: File Check
A valid polygon ring must have at least four points (three unique coordinates plus a closing point that repeats the first coordinate).
If a ring has fewer points than this minimum, the shape cannot be processed.
How to fix it
• Open the file in QGIS and identify the affected polygons
• Invalid polygons will typically appear as lines or points rather than areas
• Delete or redraw any degenerate polygons that cannot form a valid closed shape
6. Polygon or Multipolygon Contains Holes
Occurs during: System Check
TRACT does not accept polygons with interior rings (holes).
A polygon with a hole is one where a smaller polygon is cut out from the interior of a larger one.
How to fix it
• Open the file in QGIS and identify polygons with interior rings
• Remove the interior ring to create a simple polygon
• If the hole represents a genuine exclusion area, split it into separate polygons instead
7. Polygon Ring Is Not Closed
Occurs during: File Check
A polygon ring must be closed. The last coordinate must be identical to the first coordinate.
If the ring is left open, the shape is incomplete and will be rejected.
How to fix it
• Open the file in QGIS
• Most geometry repair tools will close open rings automatically
• Re-export the file after fixing the geometry to ensure all rings are properly closed
8. Invalid or Corrupted GeoJSON File
Occurs during: File Check
The file cannot be parsed as valid GeoJSON.
This usually means the file contains a structural error, such as a missing bracket, comma, quotation mark, or other formatting issue.
How to fix it
• Try opening the file in QGIS — if it cannot be loaded, the file is likely corrupted
• Re-export the GeoJSON from the source system that generated it
• If the file was exported from QGIS, use the TRACT Geolocation Formatter plugin to validate it before uploading
Tip
Before uploading, confirm that:
• Your GeoJSON file is valid and can be opened in QGIS
• Every feature contains a NodeID property
• Every NodeID exists in Master Data
• Polygon boundaries are valid and contain no self-intersections or holes
Most GeoJSON upload failures are caused by invalid geometry, missing NodeIDs, or NodeIDs that do not exist in Master Data.