Get database records with custom JSON structure about headless HOT 9 CLOSED

fields {
        content {
            fields {
                boxes = COA
                boxes {
                    stdWrap.innerWrap = [|]
                    10 = RECORDS
                    10 {
                        source.field = tx_extension_box_item
                        tables = tx_extension_box_item
                        conf.tx_extension_box_item.stdWrap.wrap = |###BREAK###
                    }
                    stdWrap.split {
                        token = ###BREAK###
                        cObjNum = 1 |*|2|*| 3
                        1.current = 1
                        1.stdWrap.wrap = |

                        2.current = 1
                        2.stdWrap.wrap = ,|

                        3.current = 1
                        3.stdWrap.wrap = |
                    }
                }
            }
        }
    }

fields {
    content {
        fields {
            pages = COA
            pages {
                stdWrap.innerWrap = [|]
                10 = CONTENT
                10 {
                    table = pages
                    select {
                        pidInList.field = pages
                        orderBy = sorting
                        recursive.field = recursive
                    }
                    renderObj =< lib.page
                    renderObj.stdWrap.wrap = |###BREAK###
                }

                stdWrap.split {
                    token = ###BREAK###
                    cObjNum = 1 |*|2|*| 3
                    1.current = 1
                    1.stdWrap.wrap = |

                    2.current = 1
                    2.stdWrap.wrap = ,|

                    3.current = 1
                    3.stdWrap.wrap = |
                }
            }
        }
    }
}

tx_extension_box_item =< lib.contentElement
tx_extension_box_item {
    fields {
        content {
            fields {
                header = TEXT
                header {
                    field = header
                }
                bodytext = TEXT
                bodytext {
                    field = bodytext
                    parseFunc =< lib.parseFunc_links
                }
                link = TEXT
                link {
                    field = link
                    typolink {
                        parameter {
                            field = link
                        }
                        returnLast = url
                    }
                }
            }
        }
    }
}

fields {
    myRecords {
        dataProcessing {
            10 = FriendsOfTYPO3\Headless\DataProcessing\JsonRecordsProcessor
            10 {
                pidInList =
                recursive =
                selectFields =
                languageField =
                where = 
                ...

                # fields with stdWrap applied (without defining Content Object)
                fields {
                    myCustomLink {
                        field = link
                        typolink {
                            parameter {
                                field = link
                            }
                            returnLast = url
                        }
                    }

                    myCustomId.field = uid

                    myCustomText.field = bodytext
                }
            }
        }
    }
}

{
    "myRecords": [
        {
            "myCustomLink": "/target/page",
            "myCustomId": 2,
            "myCustomText": "my bodytext"
        },
        {...},
        {...}
    ]
}