Swift Decoder, trying to decode file with layers - swift

Question

How would I decode this json file with JSONDecoder().decode
{
"text": "pear",
"parsed": [
{
"food": {
"foodId": "food_bq6stkiaxkwhxia9q4v7wanjnew0",
"label": "Pear",
"nutrients": {
"ENERC_KCAL": 57,
"PROCNT": 0.36,
"FAT": 0.14,
"CHOCDF": 15.23,
"FIBTG": 3.1
},
"category": "Generic foods",
"categoryLabel": "food",
"image": "https://www.edamam.com/food-img/65a/65aec51d264db28bbe27117c9fdaaca7.jpg"
}
}
],
"hints": [
{
"food": {
"foodId": "food_bq6stkiaxkwhxia9q4v7wanjnew0",
"label": "Pear",
"nutrients": {
"ENERC_KCAL": 57,
"PROCNT": 0.36,
"FAT": 0.14,
"CHOCDF": 15.23,
"FIBTG": 3.1
},
"category": "Generic foods",
"categoryLabel": "food",
"image": "https://www.edamam.com/food-img/65a/65aec51d264db28bbe27117c9fdaaca7.jpg"
},
"measures": [
{
"uri": "http://www.edamam.com/ontologies/edamam.owl#Measure_unit",
"label": "Whole",
"qualified": [
{
"qualifiers": [
{
"uri": "http://www.edamam.com/ontologies/edamam.owl#Qualifier_large",
"label": "large"
}
]
},
{
"qualifiers": [
{
"uri": "http://www.edamam.com/ontologies/edamam.owl#Qualifier_small",
"label": "small"
}
]
},
{
"qualifiers": [
{
"uri": "http://www.edamam.com/ontologies/edamam.owl#Qualifier_medium",
"label": "medium"
}
]
}
]
},
{
"uri": "http://www.edamam.com/ontologies/edamam.owl#Measure_serving",
"label": "Serving"
},
{
"uri": "http://www.edamam.com/ontologies/edamam.owl#Measure_half",
"label": "Half"
},
{
"uri": "http://www.edamam.com/ontologies/edamam.owl#Measure_slice",
"label": "Slice"
},
{
"uri": "http://www.edamam.com/ontologies/edamam.owl#Measure_gram",
"label": "Gram"
},
{
"uri": "http://www.edamam.com/ontologies/edamam.owl#Measure_ounce",
"label": "Ounce"
},
{
"uri": "http://www.edamam.com/ontologies/edamam.owl#Measure_pound",
"label": "Pound"
},
{
"uri": "http://www.edamam.com/ontologies/edamam.owl#Measure_kilogram",
"label": "Kilogram"
},
{
"uri": "http://www.edamam.com/ontologies/edamam.owl#Measure_cup",
"label": "Cup"
}
The file goes on and on.
I try to do [String] but it says it expects a dictionary,
So I put in a dictionary, then it says it expects another dictionary,
This repeats until I have this:
let posts = try! JSONDecoder().decode([String: [String: [String: String]]].self, from: data!)
Then I get the error
"Expected to decode Dictionary<String, Any> but found a string/data instead.", underlyingError: nil))
Though when I go back one to do a string/data I get this error
"Expected to decode String but found a dictionary instead.", underlyingError: nil))
Help?

Answer 1

As mentioned in the comments you can use a quick parser, however
you need to understand why is this happening, the issue here is that you're passing [String: [String: [String: String]]] which is not valid skeleton for this key you can start breaking down each layer alone to understand first level for example [String, Any] and then start exporting each key and decode that stand alone, using the above link your models should be something like that.
// MARK: - Foo
struct Foo: Codable {
let text: String
let parsed: [Parsed]
let hints: [Hint]
}
// MARK: - Hint
struct Hint: Codable {
let food: Food
let measures: [Measure]
}
// MARK: - Food
struct Food: Codable {
let foodID, label: String
let nutrients: Nutrients
let category, categoryLabel: String
let image: String
enum CodingKeys: String, CodingKey {
case foodID = "foodId"
case label, nutrients, category, categoryLabel, image
}
}
// MARK: - Nutrients
struct Nutrients: Codable {
let enercKcal: Int
let procnt, fat, chocdf, fibtg: Double
enum CodingKeys: String, CodingKey {
case enercKcal = "ENERC_KCAL"
case procnt = "PROCNT"
case fat = "FAT"
case chocdf = "CHOCDF"
case fibtg = "FIBTG"
}
}
// MARK: - Measure
struct Measure: Codable {
let uri: String
let label: String
let qualified: [Qualified]?
}
// MARK: - Qualified
struct Qualified: Codable {
let qualifiers: [Qualifier]
}
// MARK: - Qualifier
struct Qualifier: Codable {
let uri: String
let label: String
}
// MARK: - Parsed
struct Parsed: Codable {
let food: Food
}
And you can use it simply like this:
let foo = try? newJSONDecoder().decode(Foo.self, from: jsonData)