Creating a request
Use GraphRequest to build a request with a graph path and an optional parameters dictionary. The fields parameter controls which fields the API returns.
import FacebookCore
let request = GraphRequest(
graphPath: "me",
parameters: ["fields": "id,name,email"]
)
Starting with Graph API v2.4, GET requests must include an explicit fields parameter. The SDK logs a developer warning if you omit it.
Starting the request
Call start(_:) to fire the request. The completion closure receives a connection, a result, and an error.
request.start { connection, result, error in
if let error = error {
print("Request failed:", error.localizedDescription)
return
}
guard let result = result as? [String: Any] else { return }
let name = result["name"] as? String ?? ""
print("Hello, \(name)")
}
start(_:) returns an object conforming to GraphRequestConnecting that you can use to cancel the request before it completes.
HTTP methods
The SDK defines three HTTP methods:
| Constant | Value |
|---|
FBSDKHTTPMethodGET | "GET" |
FBSDKHTTPMethodPOST | "POST" |
FBSDKHTTPMethodDELETE | "DELETE" |
// POST request — e.g. publish a comment
let post = GraphRequest(
graphPath: "me/feed",
parameters: ["message": "Hello from my app!"],
httpMethod: .post
)
post.start { _, result, error in
// handle result
}
// DELETE request — e.g. remove a post
let delete = GraphRequest(
graphPath: "<post_id>",
parameters: [:],
httpMethod: .delete
)
delete.start { _, result, error in
// handle result
}
Using a specific access token
By default, GraphRequest reads the token string from AccessToken.current. To supply a different token, use the full initialiser:
let request = GraphRequest(
graphPath: "me",
parameters: ["fields": "id,name"],
tokenString: customTokenString,
version: nil,
httpMethod: .get
)
nil for tokenString causes the SDK to fall back to AccessToken.current.
Error handling
The error parameter in the completion handler is an NSError. Check error.userInfo for Graph API-specific details:
request.start { _, result, error in
if let error = error as NSError? {
let graphCode = error.userInfo[FBSDKGraphRequestErrorGraphErrorCodeKey]
let message = error.localizedDescription
print("Graph error \(graphCode ?? "unknown"): \(message)")
return
}
// process result
}
| Key | Description |
|---|
FBSDKGraphRequestErrorKey | Error category (transient, recoverable, non-recoverable) |
FBSDKGraphRequestErrorGraphErrorCodeKey | Graph API error code |
FBSDKGraphRequestErrorGraphErrorSubcodeKey | Graph API error subcode |
FBSDKGraphRequestErrorHTTPStatusCodeKey | HTTP status code |
The SDK automatically attempts error recovery for transient errors when Settings.shared.isGraphErrorRecoveryEnabled is true (the default). You can disable recovery on a per-request basis by setting request.isGraphErrorRecoveryDisabled = true.
