fix: create previews from first page on multi-page documents

[DeepDiver1975]

Description

Previews are now generated from the first page and no longer from the last page.

Related Issue

• Fixes PDF Preview only shows last section of pdf #41042

Motivation and Context

How Has This Been Tested?

• test environment:
• test case 1:
• test case 2:
• ...

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Database schema changes (next release will require increase of minor version instead of patch)
• Breaking change (fix or feature that would cause existing functionality to change)
• Technical debt
• Tests only (no source changes)

Checklist:

• Code changes
• Unit tests added
• Acceptance tests added
• Documentation ticket raised:
• Changelog item, see TEMPLATE

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

100.0% Coverage
0.0% Duplication

[phil-davis]

@DeepDiver1975 this seems like a good thing - merge?

[DeepDiver1975]

this need some more testing - as per #41042 it is not working ...... no idea if the code has issues or there have been issues in applying the patch.

[pako81]

Confirmed current code is not properly working. It seems setIteratorIndex should be used in this case, so:

$bp->readImageFile($stream);
$bp->setIteratorIndex(0);

this way previews are correctly generated from the first page of the document.

[phil-davis]

works for me. This PR is quite old, so I will rebase to get up-to-date CI with current master. Then I will try to add an acceptance test - we already have thumbnail tests, so I should be able provide a multi-page PDF as a fixture along with the expected thumbnail of the first page.

[phil-davis]

    When user "Alice" downloads the preview of "/Preview-test.pdf" with width "612" and height "792" using the WebDAV API # FeatureContext::downloadPreviewOfFiles()
    Then the HTTP status code should be "200"                                                                             # FeatureContext::thenTheHTTPStatusCodeShouldBe()
      HTTP status code 404 is not the expected value 200
      Failed asserting that 404 matches expected '200'.

Hmm, this passed for me locally. I suppose there is some setting of the max preview size or something that needs to be done to get a "large" preview like in this test.

[phil-davis]

Hmm, this passed for me locally. I suppose there is some setting of the max preview size or something that needs to be done to get a "large" preview like in this test.

Preview of PDFs is not enabled by default. I had to set it in system config enabledPreviewProviders

[sonarcloud]

Quality Gate passed

Issues
0 New issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud