Issue with JSON Decoding? / How can I debug this? - arrays

Question

I'm making an API call and managing the data received, but my call is catching an error. Here's my getData() code:
func getData(from url: String) {
URLSession.shared.dataTask(with: URL(string: url)!, completionHandler: { data, response, error in
guard let data = data, error == nil else {
print("something went wrong.")
return
}
do {
self.instructionsResults = try JSONDecoder().decode([Step].self, from: data)
print("getData() was successful!")
print(self.instructionsResults)
} catch {
print("Decoding error:")
print(String(describing: error)) // <-- this pings
}
}).resume()
}
Here's a pastebin of an example url json data: link
And here's the struct I've defined for this fetch:
struct Step: Codable {
let number: Int
let step: String?
}
This may be extra, but I'm using the call above to populate the array instantiated as var steps: [String] = [] with the step: String data of each step in the JSON Step array.
for n: Int in 0 ..< instructionsResults.count {
if instructionsResults[n].step != nil {
let step = instructionsResults[n].step ?? "n/a"
print("step: \(instructionsResults[n].step)")
print("step: \(step)")
steps.append(step)
}
}
print("Steps: \(steps)")
}
Does anyone have any insight on what's going wrong? My final print statement always returns as empty. I've done a similar type of call formatted a similar way earlier in this project, and that worked completely fine, so I'm stumped as to where I went wrong with this one. Any insight / feedback would be greatly appreciated, thank you.
Edit: Here's the error code:
Steps: []
Decoding error:
keyNotFound(CodingKeys(stringValue: "number", intValue: nil), Swift.DecodingError.Context(codingPath: [_JSONKey(stringValue: "Index 0", intValue: 0)], debugDescription: "No value associated with key CodingKeys(stringValue: \"number\", intValue: nil) (\"number\").", underlyingError: nil))

Answer 1

The error says that there is no key number in the top level object.
Please read the JSON carefully. You are ignoring the object on the root level, the array with the key steps.
You need this
struct Root: Decodable {
let steps: [Step]
}
struct Step: Decodable {
let number: Int
let step : String
}
and decode
.decode([Root].self,