incrementalPatch does not work as expected for documents with nested fields. #7430
Description
Given a document structure like
{
"foo": "bar",
"data": {
"field1": 1,
"field2": 2,
}
}a call to incrementalPatch like
doc.incrementalPatch({
data: {
field1: 3
}
})will result in a new object state like
{
"foo": "bar",
"data": {
"field1": 3,
// "field2": 2, This field was removed
}
}After looking at the implementation https://github.com/pubkey/rxdb/blob/master/src/rx-document.ts#L316
It appears that incrementalPatch simply does a "one level" shallow patch instead of a "deep merge" operation so the output would be
{
"foo": "bar",
"data": {
"field1": 3, // The field was changed, but other fields not interfered with
"field2": 2,
}
}A simple potential solution would be to leverage a package like https://www.npmjs.com/package/object-deep-merge (I cannot personally vouch for this library, it was what I found when searching) or to implement that functionality manually in RxDB.
That would mean updating the current implementation from
incrementalPatch<RxDocumentType = any>(
this: RxDocument<RxDocumentType>,
patch: Partial<RxDocumentType>
): Promise<RxDocument<RxDocumentType>> {
return this.incrementalModify((docData) => {
Object
.entries(patch)
.forEach(([k, v]) => {
(docData as any)[k] = v;
});
return docData;
});
},to something like
incrementalPatch<RxDocumentType = any>(
this: RxDocument<RxDocumentType>,
patch: Partial<RxDocumentType>
): Promise<RxDocument<RxDocumentType>> {
return this.incrementalModify((docData) => {
return merge(docData, patch);
});
},I would be happy to provide further context to help prove the existence of the problem, and write a PR with the proposed change if this seems acceptable.