Food details and portions

Finding a food and choosing how much was eaten are separate steps. These examples use the client from Authentication.

Autocomplete ─▶ Search ─▶ foods.get(id:) ─▶ Portion
search text     results    every serving    computed locally

1. Autocomplete suggests search text

Call autocomplete while the user types. A suggestion is text, not a food with servings: when the user picks one, search for its name.

let suggestions = try await client.foods.autocomplete(.init(query: "greek yog", limit: 8))
guard let name = suggestions.items.first?.name else { return }

let results = try await client.foods.search(.init(query: name, category: .branded))

2. Fetch the full food before showing servings

Search results are for choosing a food. When the user picks one, fetch the full food with foods.get(id:); it includes every ServingOption:

guard let selected = results.items.first else { return }
let food = try await client.foods.get(id: selected.id)

3. Compute the portion locally

portion(servingID:quantity:) checks the serving and quantity, scales nutrition, weight, and glycemic load, and returns the FoodSelection that food logs and glucose predictions take:

// One primary serving.
let portion = try food.portion()
print(portion.serving.unit ?? "", portion.nutrition.calories?.value ?? 0)

let selection: FoodSelection = portion.selection

// With a "6 oz" primary serving: 9 oz, one and a half servings.
let larger = try food.portion(quantity: 9)

Without a servingID, it uses the primary serving (or the first one). Changing the serving or quantity needs no network call. portion throws FoodPortionError when the food has no servings, the serving isn't found, or the quantity is invalid.

Quantity and servings

quantity is an amount in the serving's unit, not a number of servings. For a "6 oz" serving (quantity 6, unit "oz"), quantity: 9 means 9 oz, and leaving quantity out means one serving (6 oz). portion.selection sends the number of servings, quantity divided by the serving's own quantity, so 9 oz of a "6 oz" serving is logged as 1.5 servings. Versions before 0.3.2 sent quantity itself as the number of servings, so food logs and glucose predictions got the wrong amount (a default "6 oz" portion was logged as 6 servings); upgrade to 0.3.2.

Next: Foods.