Fix file caching in JsonFileInterpreter.

[cancan101]

JSON version of PR #438
Pulled out of #437 (comment)

CC @fashxp

[fashxp]

since this is a bugfix, please rebase to 1.10

[fashxp]

just for the record: the file caching makes sense because methods fileValid and previewData or doInterpretFileAndCallProcessRow are called after each other. to aviod double loading of the data source, this cache was introduced (but never worked properly it seems ;-) )

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

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

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[blankse]

@cancan101 @fashxp I think we should write the cache also in the loadData method and the fileValid should use the loadData method. Now it has redundant loading code. WDYT?

[cancan101]

I think there is more that can be done with the caching and I would also suggest reviewing the control flow for error handing (e.g. pass JSON_THROW_ON_ERROR to json_decode and doing so at both call points).

That said, these changes are becoming too much for me to take on.

[blankse]

Variable exists always. We should compare it with null.

Suggested change

	if ($this->cachedFilePath !== $path || empty($this->cachedContent)) {
	if ($this->cachedFilePath !== $path || $this->cachedContent === null) {

[cancan101]

@blankse the suggestions might be easier after this PR: https://github.com/pimcore/data-importer/pull/437/files#diff-a36a911bb91e74bc3b35f4779ac1a1dd970ab78d93b7df9d4b2df64846259d9fR45-R57 with the load factored out and then can change such that both loads use that function.

[blankse]

@cancan101 But there is also the error handling and the cache writing only in the fileValid method. I think this should be also moved in the loading method.

[cancan101]

yes see my linked PR and comment.