Support for "create or update" and/or "find or create" logic with the atomic extension #1628
Description
When dealing with related/dependent resources, I think it would be useful to "create or update" and/or "find or create" certain records.
Say for example you have some type of post resource that can have tag resources associated with it.
If I know that all the tags in the request exist, I can do this
POST /api/posts
{
"data": {
"type": "post",
"attributes": {
"title": "foo",
"body": "bar"
},
"relationships": {
"tags": {
"data": [
{ "id": "tech", "type": "tag" },
{ "id": "api", "type": "tag" }
]
}
}
}
}If I know that all the tags are new, I can do this
{
"atomic:operations": [
{
"op": "add",
"data": {
"type": "tag",
"lid": "tech",
"attributes": {
"text": "tech"
}
}
},
{
"op": "add",
"data": {
"type": "tag",
"lid": "api",
"attributes": {
"text": "api"
}
}
},
{
"op": "add",
"data": {
"type": "post",
"lid": "new-post-1",
"attributes": {
"title": "foo",
"body": "bar"
},
"relationships": {
"tags": {
"data": [
{ "lid": "tech", "type": "tag" },
{ "lid": "api", "type": "tag" }
]
}
}
}
}
]
}But if I don't know about the existence of these tags prior the creation of the post, I would need to first do a GET and attempt to fetch these tags. However, since there's pretty logical/predictable defaults for this tag resource, it doesn't seem like this GET should be necessary.
My thought would be to add find_or_create and create_or_update operations and add a find_by member.
{
"op": "find_or_create",
"find_by": ["text"],
"data": {
"lid": "tech",
"type": "tag",
"attributes": { "text": "tech" }
}
}find_by would accept an array of attributes that define a composite key and use the values specified in attributes to make that query. before attempting to create the record.
May also be reasonable to also accept lid instead of an array of attributes and attempt to match an existing resource id to the specified lid
{
"op": "find_or_create",
"find_by": "lid",
"data": {
"lid": "tech",
"type": "tag",
"attributes": { "text": "tech" }
}:
}