Connect or Create-and-Connect, FaunaDB UDF body definition

function-up_nect.js

{
  name: "up_nect",
  body: Query(
    Lambda(
      ["commitSha", "filesMeta"],
      Let(
        {
          createdGitRefDoc: Create(Collection("GitRef"), {
            data: { commitSha: Var("commitSha") }
          }),
          createdGitRefRef: Select(["ref"], Var("createdGitRefDoc")),
          filesMetaShas: Map(
            Var("filesMeta"),
            Lambda("fileMeta", Select(["sha"], Var("fileMeta")))
          ),
          filesMetaMatches: Filter(
            Map(
              Var("filesMetaShas"),
              Lambda(
                "sha",
                Let(
                  {
                    match: Match(
                      Index("shaAndRef_of_FileMeta_by_sha"),
                      Var("sha")
                    )
                  },
                  If(
                    Exists(Var("match")),
                    Select(["data", 0], Paginate(Var("match"))),
                    null
                  )
                )
              )
            ),
            Lambda("match", Not(IsNull(Var("match"))))
          ),
          existingFilesMetaShas: Map(
            Var("filesMetaMatches"),
            Lambda("match", Select(0, Var("match")))
          ),
          existingFilesMetaRefs: Map(
            Var("filesMetaMatches"),
            Lambda("match", Select(1, Var("match")))
          ),
          newFilesMetaShas: Difference(
            Var("filesMetaShas"),
            Var("existingFilesMetaShas")
          ),
          newFilesMeta: Filter(
            Var("filesMeta"),
            Lambda(
              "fileMeta",
              IsNonEmpty(
                Intersection(
                  [Select("sha", Var("fileMeta"))],
                  Var("newFilesMetaShas")
                )
              )
            )
          ),
          createdFilesMeta: Map(
            Var("newFilesMeta"),
            Lambda(
              "fileMeta",
              Create(Collection("FileMeta"), { data: Var("fileMeta") })
            )
          ),
          createdLinksOnNew: Map(
            Var("createdFilesMeta"),
            Lambda(
              "fileMeta",
              Create(Collection("fileMeta_gitRefs"), {
                data: {
                  gitRefID: Var("createdGitRefRef"),
                  fileMetaID: Select(["ref"], Var("fileMeta"))
                }
              })
            )
          ),
          createdLinksOnExisting: Map(
            Var("existingFilesMetaRefs"),
            Lambda(
              "fileMetaRef",
              Create(Collection("fileMeta_gitRefs"), {
                data: {
                  gitRefID: Var("createdGitRefRef"),
                  fileMetaID: Var("fileMetaRef")
                }
              })
            )
          )
        },
        {
          gitRef: Var("createdGitRefDoc"),
          newFiles: Var("createdFilesMeta"),
          newLinks: Union(
            Var("createdLinksOnNew"),
            Var("createdLinksOnExisting")
          )
        }
      )
    )
  )
}

index-shaAndRef_of_FileMeta_by_sha.js

{
  name: "shaAndRef_of_FileMeta_by_sha",
  unique: false,
  serialized: true,
  source: "FileMeta",
  terms: [
    {
      field: ["data", "sha"]
    }
  ],
  values: [
    {
      field: ["data", "sha"]
    },
    {
      field: ["ref"]
    }
  ]
}