NowAPIService class- iOS

The NowAPIService class provides functions that enable you to perform requests to a specified ServiceNow REST API.

Name Type Description configuration NowServiceConfiguration Service configuration to associate with the protocol.

Parent Topic:Mobile SDK - iOS

NowAPIService - data(for endpoint: NowAPIEndpoint, queryItems: [String: String], httpHeaders: [String: String], body: Data, completion: @escaping (Result<DataResponse, NowDataError>)

Requests data from the specified ServiceNow REST API and then executes the completion handler.

<table id=“table_jck_kyp_5pb” class=“parameters”><thead><tr><th>

Name

</th><th>

Type

</th><th>

Description

</th></tr></thead><tbody><tr><td>

for endpoint

</td><td>

NowAPIEndpoint

</td><td>

Object containing the ServiceNow REST API endpoint to access, including the HTTP method, relative path to the endpoint, path parameters, and whether authentication is required.

</td></tr><tr><td>

queryItems

</td><td>

Array

</td><td>

Optional. Query parameters for the endpoint as key/value pairs.Default: nil

</td></tr><tr><td>

httpHeaders

</td><td>

Array

</td><td>

Optional. Request HTTP headers required by the endpoint as key/value pairs. Default: nil

</td></tr><tr><td>

body

</td><td>

String

</td><td>

Optional. Request body parameters.Default: nil

</td></tr><tr id=“mobilesdkiOS-completion_data_dataerror-row”><td>

completion

</td><td>

@escaping (Result<DataResponse, NowDataError>)

</td><td>

Completion handler to execute after the REST API call completes. Return values for the completion handler:

• Success: DataResponse that contains the returned data from the REST API call.

• Failure: NowDataError

  • accessToken(AccessTokenProviderError)

  • accessToken(AccessTokenProviderError)

    • AccessTokenProviderError: The access token provider’s error code or message.

      • accessTokenRetrievalFailed

      • userSessionError(_ error: Error) Thrown when there is an error in the access token.

  • attachmentValidation

Thrown when an attachment fails validation.

-   `badResponse(statusCode: HTTPStatusCode)`

    -   **HTTPStatusCode**: Status code received from the instance.

Thrown when a request returns an unexpected response

-   `cannotDecodeModel(DecodingError)`

    -   **DecodingError**: Decoding error detected.

Thrown when a Codable model cannot be decoded from JSON.

-   `cannotDecodeProperty(type: Any, from: String)`

    -   **type**: Wrapped type to decode from a string.
    -   **from**: String to decode to the specified type.

Thrown when a string-wrapped value cannot be decoded from JSON.

-   `cannotEncodeModel(EncodingError)`

    -   **EncodingError**: Encoding error detected.

Thrown when a Codable model cannot be encoded to JSON.

-   `cannotParseResponse`

Thrown when a response from the instance cannot be parsed into its expected format.

-   `invalidURL`

Thrown when a URL cannot be formed. For example, if the string contains characters that are illegal in a URL or is an empty string.

-   `missingAttachmentMetadata`

Thrown when the attachment metadata header is missing.

-   `missingServiceConfiguration`

Thrown when an expected service configuration is missing.

-   `missingSysID`

Thrown when an expected sys_id parameter is missing.

-   `network(NetworkServiceError)`

    -   genericError\(String\)
    -   operationCanceled
    -   service​Disabled
    -   serverError\(Error\)
    -   systemError\(Error\)

Thrown when a network service encountered an error.

</td></tr></tbody> </table>|Type|Description| |—-|———–| |None| |

The following code example shows how to call this function.

struct Endpoint: NowAPIEndpoint {
  let httpMethod: HTTPMethod
  let relativePath: String
  let requiresAuthentication: Bool
}

/// HTTP request method
public enum HTTPMethod: CaseIterable {
    case options, get, head, post, put, patch, delete, trace, connect
}
let relativePath = “/api/now/account”
let endPoint = Endpoint(httpMethod: HTTPMethod.get, relativePath: relativePath, requiresAuthentication: true)

apiService.data(for: endPoint, queryItems: [“name”: “abel”], httpHeaders: httpHeaders, body: body.data(using: .utf8)) { [weak self] (result) in
  switch result {
    case .success(let response):
    // Data request successful
    case .failure(let error):
    // Data request failed, return NowDataError
    // .failure(error)
  }
}

NowAPIService - data(for endpoint: NowAPIEndpoint, queryItems: [String: String], httpHeaders: [String: String], body: Data) async throws

Requests data from the specified ServiceNow REST API.

<table id=“table_jck_kyp_5pb” class=“parameters”><thead><tr><th>

Name

</th><th>

Type

</th><th>

Description

</th></tr></thead><tbody><tr><td>

for endpoint

</td><td>

NowAPIEndpoint

</td><td>

Object containing the ServiceNow REST API endpoint to access, including the HTTP method, relative path to the endpoint, path parameters, and whether authentication is required.

</td></tr><tr><td>

queryItems

</td><td>

Array

</td><td>

Optional. Query parameters for the endpoint as key/value pairs.Default: nil

</td></tr><tr><td>

httpHeaders

</td><td>

Array

</td><td>

Optional. Request HTTP headers required by the endpoint as key/value pairs. Default: nil

</td></tr><tr><td>

body

</td><td>

String

</td><td>

Optional. Request body parameters.Default: nil

</td></tr></tbody> </table><table id=“table_kck_kyp_5pb” class=“returns”><thead><tr><th>

Type

</th><th>

Description

</th></tr></thead><tbody><tr><td>

DataResponse

</td><td>

Returned when the method is successful. Data from the REST API call.

</td></tr><tr><td>

NowDataError

</td><td>

Thrown when the method fails. - accessToken(AccessTokenProviderError)

-   **AccessTokenProviderError**: The access token provider's error code or message.
    -   accessTokenRetrievalFailed
    -   userSessionError\(\_ error: Error\)

Thrown when there is an error in the access token.

• attachmentValidation

Thrown when an attachment fails validation.

• badResponse(statusCode: HTTPStatusCode)

  • HTTPStatusCode: Status code received from the instance. Thrown when a request returns an unexpected response

• cannotDecodeModel(DecodingError)

  • DecodingError: Decoding error detected. Thrown when a Codable model cannot be decoded from JSON.

• cannotDecodeProperty(type: Any, from: String)

  • type: Wrapped type to decode from a string.

  • from: String to decode to the specified type. Thrown when a string-wrapped value cannot be decoded from JSON.

• cannotEncodeModel(EncodingError)

  • EncodingError: Encoding error detected. Thrown when a Codable model cannot be encoded to JSON.

• cannotParseResponse

Thrown when a response from the instance cannot be parsed into its expected format.

• invalidURL

Thrown when a URL cannot be formed. For example, if the string contains characters that are illegal in a URL or is an empty string.

• missingAttachmentMetadata

Thrown when the attachment metadata header is missing.

• missingServiceConfiguration

Thrown when an expected service configuration is missing.

• missingSysID

Thrown when an expected sys_id parameter is missing.

• network(NetworkServiceError)

  • genericError(String)

  • operationCanceled

  • service​Disabled

  • serverError(Error)

  • systemError(Error) Thrown when a network service encountered an error.

</td></tr></tbody> </table>The following code examples shows how to call this method.

do {
    let dataResponse = try await apiService.data(for: endpoint, queryItems: queryItems, httpHeaders: httpHeaders, body: body)
    // Data request successful
} catch {
    // Data request failed, NowDataError thrown
}

NowAPIService - data(for endpoint: NowAPIEndpoint, queryItems: [String: String]? = nil, httpHeaders: [String: String]? = nil, body: Data? = nil)

Requests data from the specified ServiceNow REST API.

Note: This method has been deprecated. You should use the async/await implementation of the method instead.

<table id=“table_sfb_5tp_5pb” class=“parameters”><thead><tr><th>

Name

</th><th>

Type

</th><th>

Description

</th></tr></thead><tbody><tr><td>

for endpoint

</td><td>

NowAPIEndpoint

</td><td>

Object containing the ServiceNow REST API endpoint to access, including the HTTP method, relative path to the endpoint, path parameters, and whether authentication is required.

</td></tr><tr><td>

queryItems

</td><td>

Array

</td><td>

Optional. Query parameters for the endpoint as key/value pairs.Default: nil

</td></tr><tr><td>

httpHeaders

</td><td>

Array

</td><td>

Optional. Request HTTP headers required by the endpoint as key/value pairs.Default: nil

</td></tr><tr><td>

body

</td><td>

Data

</td><td>

Optional. Request body parameters. Default: nil

</td></tr></tbody> </table><table id=“table_tfb_5tp_5pb” class=“returns”><thead><tr><th>

Type

</th><th>

Description

</th></tr></thead><tbody><tr><td>

AnyPublisher<DataResponse, NowDataError>

</td><td>

Success: Data returned by the REST API.Failure: NowDataError

• accessToken(AccessTokenProviderError)

  • AccessTokenProviderError: The access token provider’s error code or message.

    • accessTokenRetrievalFailed

    • userSessionError(_ error: Error) Thrown when there is an error in the access token.

• attachmentValidation

Thrown when an attachment fails validation.

• badResponse(statusCode: HTTPStatusCode)

  • HTTPStatusCode: Status code received from the instance. Thrown when a request returns an unexpected response

• cannotDecodeModel(DecodingError)

  • DecodingError: Decoding error detected. Thrown when a Codable model cannot be decoded from JSON.

• cannotDecodeProperty(type: Any, from: String)

  • type: Wrapped type to decode from a string.

  • from: String to decode to the specified type. Thrown when a string-wrapped value cannot be decoded from JSON.

• cannotEncodeModel(EncodingError)

  • EncodingError: Encoding error detected. Thrown when a Codable model cannot be encoded to JSON.

• cannotParseResponse

Thrown when a response from the instance cannot be parsed into its expected format.

• invalidURL

Thrown when a URL cannot be formed. For example, if the string contains characters that are illegal in a URL or is an empty string.

• missingAttachmentMetadata

Thrown when the attachment metadata header is missing.

• missingServiceConfiguration

Thrown when an expected service configuration is missing.

• missingSysID

Thrown when an expected sys_id parameter is missing.

• network(NetworkServiceError)

  • genericError(String)

  • operationCanceled

  • service​Disabled

  • serverError(Error)

  • systemError(Error) Thrown when a network service encountered an error.

</td></tr></tbody> </table>The following code example shows how to call this function.

struct Endpoint: NowAPIEndpoint {
    let httpMethod: HTTPMethod
    let relativePath: String
    let requiresAuthentication: Bool
}

/// HTTP request method
public enum HTTPMethod: CaseIterable {
    case options, get, head, post, put, patch, delete, trace, connect
}
let relativePath = "/api/now/account"
let endPoint = Endpoint(httpMethod: HTTPMethod.get, relativePath: relativePath, requiresAuthentication: true)

// Using Combine
apiService.data(for: Endpoint(httpMethod: httpMethod, relativePath: endpointPath, requiresAuthentication: requiresAuthentication), queryItems: queryItems, httpHeaders: httpHeaders, body: body.data(using: .utf8))
  .receive(on: DispatchQueue.main)
  .sink { [weak self] (comp) in
    if case let .failure(error) = comp {
      // Data request failed, return NowDataError
    }
  } receiveValue: { [weak self] (response) in
    // Data request successful
    self?.publish(data: response.data)
  }
  .store(in: &self.subscriptions)
}