Apify and Crawlee Official Forum

Updated 3 months ago

Output schema

Hi, I'm having 2 issues with output schema definition:
  • I can't make transformations.unwind work, the table only shows undefined values -> Is there a working example I can check somewhere?
  • When instead using transformations.flatten, it seems the table can't show fields with array or object format, it shows undefined instead. Am I missing something here?
For reference, my result is formatted like this, and i want to unwind/flatten the data part:
Plain Text
[
  {
    "metadata": {
      "timestamp": "2024-07-08T09:51:31.942Z",
      "run_id": "lWmckTaBAlbeKTM33"
    },
    "data": {
      "url": "some_url.com",
      "title": "some title",
      "attributes": ["a", "b"]
    }
  },
  {...}
]

And I'd like the table to show the columns:
  • "metadata" as object (this works)
  • "url" as link (works only when using flatten, not unwind)
  • "title" as text (same)
  • "attributes" as array (shows undefined)
Here is the docs I've been using https://docs.apify.com/platform/actors/development/actor-definition/output-schema
O
J
9 comments
Please provide your exact reproduction (JSON with output_schema).

It should be straightforward and shouldn't cause any issues. The documentation is clear and simple, so there might be a mistake in your JSON structure.
Hi , thanks for your answer.
Here is my output definition:
Plain Text
{
    "actorSpecification": 1,
    "fields": {},
    "views": {
        "price_monitor": {
            "title": "Price Monitor",
            "description": "`PriceMonitor` output schema.",
            "transformation": {
                "fields": [
                    "metadata",
                    "data.url",
                    "data.id",
                    "data.title",
                    "data.brand",
                    "data.price"
                ],
                "flatten": [
                    "data"
                ]
            },
            "display": {
                "component": "table",
                "properties": {
                    "metadata": {
                        "format": "object"
                    },
                    "data.url": {
                        "label": "URL",
                        "format": "link"
                    },
                    "data.id": {
                        "label": "ID",
                        "format": "text"
                    },
                    "data.title": {
                        "label": "Title",
                        "format": "text"
                    },
                    "data.brand": {
                        "label": "Brand",
                        "format": "text"
                    },
                    "data.price": {
                        "label": "Price",
                        "format": "object"
                    }
                }
            }
        }
    }
}

As you see (first image) the price should be an object but is instead undefined, even though the price json is present in the full data (second image).
Attachments
Screenshot_2024-07-08_at_22.49.09.png
image.png
If i try using unwind with this config:
Plain Text
{
    "actorSpecification": 1,
    "fields": {},
    "views": {
        "price_monitor": {
            "title": "Price Monitor",
            "description": "`PriceMonitor` output schema.",
            "transformation": {
                "fields": [
                    "metadata",
                    "url",
                    "id",
                    "title",
                    "brand",
                    "price"
                ],
                "flatten": [
                    "unwind"
                ]
            },
            "display": {
                "component": "table",
                "properties": {
                    "metadata": {
                        "format": "object"
                    },
                    "url": {
                        "label": "URL",
                        "format": "link"
                    },
                    "id": {
                        "label": "ID",
                        "format": "text"
                    },
                    "title": {
                        "label": "Title",
                        "format": "text"
                    },
                    "brand": {
                        "label": "Brand",
                        "format": "text"
                    },
                    "price": {
                        "label": "Price",
                        "format": "object"
                    }
                }
            }
        }
    }
}

then it's all undefined
Attachment
image.png
unwind usage should look like this:

Plain Text
 
                 "transformation": {
                      "fields": [
                          "searchQuery",
                          "resultsTotal",
                          "organicResults"
                      ],
                      "unwind": [
                          "organicResults"
                      ]
                  },


And not
Plain Text
                "flatten": [
                    "unwind"
                ]
try to debug it with smaller / simpler output object. and then increase complexity step by step (I mean add nested obj, and so on...).
check this working example for inspiration:

Plain Text
        "views": {
          "overview": {
            "title": "Overview",
            "description": "",
            "transformation": {
              "fields": [
                "thumbnailImage",
                "asin",
                "title",
                "description",
                "brand",
                "stars",
                "reviewsCount",
                "price.value",
                "breadCrumbs",
                "url"
              ],
              "flatten": [
                "price"
              ]
            },
            "display": {
              "component": "table",
              "properties": {
                "thumbnailImage": {
                  "label": "Image",
                  "format": "image"
                },
                "asin": {
                  "label": "ASIN"
                },
                "description": {
                  "format": "text"
                },
                "stars": {
                  "format": "number"
                },
                "reviewsCount": {
                  "format": "number"
                },
                "price.value": {
                  "label": "Price",
                  "format": "number"
                },
                "breadCrumbs": {
                  "label": "Categories"
                },
                "url": {
                  "label": "URL",
                  "format": "link"
                }
              }
            }
          }
        }
Ofc my bad for the typo, I did use "unwind" as a key, but still could not make it work.
If i do "unwing": ["data"], and data contains a url field, what should i list in the fields? I've tried url and data.url adn both end up undefined.

In your example with flatten none of the fields are of type array or object (they are image, text or number only), which are the types I'm having trouble with...
So with unwind I'm able to move children into a parent object as expected, but in the table view it always appears as undefined. What should be in the field list when using unwind?
Attachments
image.png
image.png
image.png
Any insight on this ?
Add a reply
Sign up and join the conversation on Discord