Differences between the mock and the real Vuforia Web Services¶
The mock attempts to be realistic, but it was built without access to the source code of the original API. Please report any issues here.
Image matching¶
Vuforia’s image matching is proprietary and we do not intend to accurately copy it.
Instead, we aim for simple algorithms which are fast and are good enough for testing purposes.
The image matcher is configurable, using match_checker.
Speed and summary accuracy¶
The mock responds much more quickly than the real Vuforia Web Services.
Targets in the mock are set to ‘processing’ for half a second by default.
This is customizable, with the processing_time_seconds parameter.
In the real Vuforia Web Services, the processing stage takes varying lengths of time.
The database summary in the real Vuforia Web Services takes some time to account for images and recognitions. Sometimes the real summary skips image states such as the processing state. The mock is accurate immediately with regards to images. The mock does not count recognitions.
Image quality and ratings¶
Targets are assigned a rating between 0 and 5 of how good they are for tracking purposes.
In the mock this is calculated from the image quality, differently to how Vuforia does this.
This is customizable with the target_tracking_rater parameter.
Image targets which are not suited to detection are given ‘failed’ statuses. The criteria for these images is not defined by the Vuforia documentation. The mock is more forgiving than the real Vuforia Web Services. Therefore, an image given a ‘success’ status by the mock may not be given a ‘success’ status by the real Vuforia Web Services.
Matching recently deleted targets¶
Vuforia may match targets which have been deleted within the last few seconds. In the mock, targets are not matched after they have been deleted.
Accepted date formats for the Query API¶
The Query API documentation is not clear on which date formats are expected exactly in the Date header.
The mock is strict.
That is, it accepts only a few date formats, and rejects all others.
If you find a date format which is accepted by the real Query API but rejected by the mock, please create a GitHub issue.
Targets stuck in processing¶
On the real Vuforia Web Services, targets sometimes get stuck in the processing state.
For example, targets with the name \uffff get stuck in the processing state.
On the mock, no targets get stuck in the processing state.
Database summary quotas¶
The database summary endpoint returns quotas which match the quotas given for a free license.
transfer-encoding headers¶
Sometimes the real Query API sends responses with transfer-encoding: chunked and no Content-Length header.
The mock does not do this.
Content-Encoding headers¶
The real Query API sends some responses with Content-Encoding: gzip.
The mock Query API sends all responses with Content-Encoding: gzip.
NGINX Error cases¶
Vuforia uses NGINX.
This has error handling which is not duplicated in the mock.
For example, Vuforia returns a 400 (BAD REQUEST) response if a header or cookie is given which is larger than 8 KiB.
Result codes¶
Result codes are returned by requests to Vuforia to help with debugging. See VWS API Result Codes for details of the available result codes. There are some result codes which the mock cannot return.
These are:
DateRangeErrorProjectHasNoAPIAccessProjectSuspendedRequestQuotaReachedTargetQuotaReachedTooManyRequests
Content-Length headers¶
When the given Content-Length header does not match the length of the given data, the mock server (written with Flask) will not behave as the real Vuforia Web Services behaves.
Header cases¶
The mock does not necessarily match Vuforia for all header cases.