Test to open images and file information

[zarda]

For #165 and #221, to test requesting the information of files and opening the images.

OPEN_IMAGE_PV will test the image containing pv data.
OPEN_IMAGE_CASA_VARIENTS will test the variant casa images.
FILEINFO_CASA_VARIENTS will check out the file info in the variant casa images.

Use Jest.toMatchSnapshot() to see if the responding message is as exact as expected.

[ajm-ska]

It works on Ubuntu.

I copied over the new /set_casaImageVarients folder to the Mac, but unfortunately there is a problem with these new 'snapshot' files. For example,

-     "date": "1575483289",
+     "date": "1618195790",
      "name": "componentlist.image",
      "size": "1880126",

-     "date": "1575483289",
+     "date": "1618195859",
      "name": "concatenated.image",
      "size": "1134908779",

            "entryType": "FLOAT",
            "name": "OBSDEC",
-           "numericValue": 13.277961108781836,
+           "numericValue": 13.277961108781838,
            "value": "1.327796110878E+01",

Could it be that the image files on the Mac are different (older versions) compared the ones currently on almalustre?

[zarda]

If the header item is trivial, we might skip it. Such as the file 'date' of creation.
The precision of float number would be considered as a test case.

[ajm-ska]

Now the only problem is the float number in OPEN_IMAGE_CASA_VARIENTS.test.ts

-         "numericValue": 13.277961108781836,
+         "numericValue": 13.277961108781838,
          "value": "1.327796110878E+01",

How accurate does it need to be?

[zarda]

Suppose it's enough to set 4 digits here.

[kswang1029]

it is better to use relative error and tolerance.

[zarda]

How about verify its digits after transferring this float number to an exponential float number?
0.001234321 -> 1.234321E-3 -> 1.234E-3
........................................^

[acdo2002]

So far testing with Ubuntu and MacOS, they works fine with ws.
Even generating the snapshots folder at the first run.

[ajm-ska]

Good. Seems fine on Ubuntu and MacOS now.