Post only non-null values in request body for createTree

[asthinasthi]

Description

Github release 2.18+ doesn't accept sha:null in the request body. This change fixes that. More details here: #636

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[bitwiseman]

@asthinasthi
This is really good. Thanks! This is the behavior for GHE. Is it the same for GitHub.com?

[asthinasthi]

Actually I see that we have deprecated this https://github.com/github-api/github-api/blob/d1507f26668950508e0bf242c34cdb599003991a/src/main/java/org/kohsuke/github/GHTreeBuilder.java#L111
in the latest release (I was using 1.93).

So when we use the recommended
https://github.com/github-api/github-api/blob/d1507f26668950508e0bf242c34cdb599003991a/src/main/java/org/kohsuke/github/GHTreeBuilder.java#L129

    public GHTreeBuilder add(String path, byte[] content, boolean executable) {
        try {
            String dataSha = repo.createBlob().binaryContent(content).create().getSha();
            return shaEntry(path, dataSha, executable);
        } catch (IOException e) {
            throw new GHException("Cannot create binary content of '" + path + "'", e);
        }
    }

We create a sha & then use it in the API. We never send a null sha field.

Also, we have deprecated shaEntry(path, dataSha, executable) so I think we are good.

[bitwiseman]

@asthinasthi
Um, so, do you want to close this or still merge it?

[asthinasthi]

We can close this. As long as I stay away from deprecated methods I should be fine.

[Xcelled]

Can this be reopened and merged? I just got bit by this issue in deployed production code after a GH:E upgrade and it took me forever to track it down.

[bitwiseman]

Suggested change

	@JsonInclude(Include.NON_NULL)
	// Issue #636: Create Tree no longer accepts null value in sha field
	@JsonInclude(Include.NON_NULL)