Image API conformance¶

iiisight can probe an Image API service for conformance: it loads info.json, issues the requests appropriate to the service’s claimed compliance level, and — for requests whose output size is predictable — verifies the server returns an image of the expected pixel dimensions, not merely an HTTP 200.

Dimensions are read straight from the returned image’s header (JPEG / PNG / GIF), so there is no image-decoding dependency — the probe is built in.

Probing a service¶

Pass an image-service base URL, an already-loaded ImageService, or a Canvas (its primary image service is used):

Async

async with iiisight.AsyncClient() as client:
    report = await client.check_compliance("https://example.org/iiif/image")

Sync

with iiisight.Client() as client:
    report = client.check_compliance("https://example.org/iiif/image")

The report¶

check_compliance returns a ConformanceReport:

report.claimed_level        # e.g. "level2"
report.conforms             # did every check at/below the claimed level pass?
report.summary()            # "5/6 checks passed; conforms to level2"
for check in report.failed:  # also .passed / .checks
    print(check.name, check.url, check.detail)

Each Check records a feature (full image, sizeByW, regionByPx, regionByPct, rotationBy90, a listed size), the level it belongs to, the URL requested, whether it passed, and a human detail like got 500x400, expected ~500x400.

The probe only issues requests appropriate to the claimed level (a level0 service is checked against full/max and its advertised sizes; level1/level2 features are checked only when claimed), so conforms answers “does the server honor the level it advertises?”

From the command line¶

$ iiisight probe https://example.org/iiif/image
https://example.org/iiif/image  claimed: level2
  PASS  full image     got 6000x4000, expected ~6000x4000
  PASS  sizeByW        got 3000x2000, expected ~3000x2000
  FAIL  regionByPx     got 6000x4000, expected ~3000x2000
  ...
4/6 checks passed; does NOT conform to level2

Exits 0 when the service conforms, 1 when it doesn’t, 2 on error. --json emits the full report.

Measuring image dimensions directly¶

The header reader is exposed as iiisight.image_size() if you want it:

width_height = iiisight.image_size(jpeg_or_png_or_gif_bytes)   # (w, h) or None