Import/Add history and comments for existing issues through JSON

[M_S_]

I am trying to import and add history entries and comments for existing issues through JSON. I know how to properly write JSON for history and comments, but struggle with referencing the existing issues. 

I thought, the JSON file would simply reference the existing issue's key:

{
	"projects": [
		{
			"key": "PRJ",
			"issues": [
				{
					"key": "PRJ-222",
					"history": [ ... ],
					"comments": [ ... ]
				}
			]
		}
	]
}

However, importing this fails claiming that no summary is set. If I provide the existing summary in the JSON file, then the import succeeds, but clears all other fields in the issues (such as fixVersion, components, etc.).

How do I correctly import and add the elements without overwriting the issue?

[Marc Minten _EVS_]

Hi, I use JSON import regularly to add comments to existing issues, and it works fine, leaving the other fields unchanged (using the JSON structure as you describe). I did not try to add history items yet.

I think even that if you add the summary field, it will simply overwrite the summary field but never clear the other fields ??? (to be clear: I never tried this)

I did a quick test: here's my JSON file

{"projects": [{"issues": [{"comments": [{"body": "This is my test comment"}],
                           "key": "MUL-2128"}
                         ],
                "key": "MUL"}
            ]
}

It says : No errors, "no Issues and projects imported". But the comment was added correctly to my issue.

I am using JIRA 6.3.12 (know there are improvements in this area in the different 6.x versions)