Class WebhookRequestParser

Namespace

Line.OpenApi.Messaging.Webhook

Assembly

Line.OpenApi.Messaging.Webhook.dll

Entry point for receiving LINE webhooks. A thin helper that bundles x-line-signature signature validation (WebhookSignatureValidator) and deserialization of the body into Line.OpenApi.Messaging.Webhook.Generated.Models.CallbackRequest into a single call.

Deserialization is done by instantiating Microsoft.Kiota.Serialization.Json.JsonParseNodeFactory directly and does not depend at all on Kiota's global default serializer registry (ParseNodeFactoryRegistry.DefaultInstance / ApiClientBuilder.RegisterDefaultDeserializer). (KiotaJsonSerializer internally consults that default registry, so it fails in a clean process where no JSON factory has been registered. Using the factory directly does not carry that assumption.) As a result it works standalone even in an app that has not constructed the Messaging client, and has no side effects (the regression is guarded by the standalone assembly Line.OpenApi.Messaging.Webhook.IsolationTests).

Polymorphic reconstruction of the event array (dispatch to Line.OpenApi.Messaging.Webhook.Generated.Models.MessageEvent etc. by the type discriminator, with a fallback to the base Line.OpenApi.Messaging.Webhook.Generated.Models.Event for unknown types) is handled by the generated code. This helper only returns the Line.OpenApi.Messaging.Webhook.Generated.Models.CallbackRequest; the subsequent event branching is done on the caller side (see README).

Example usage with ASP.NET Core (obtaining the raw body and signature header is the caller's responsibility):

var body = await ReadRawBodyBytesAsync(Request);          // raw bytes (same as what is signed)
var sig  = Request.Headers["x-line-signature"];
CallbackRequest callback = await parser.ParseAsync(body, sig);  // throws on invalid signature

public sealed class WebhookRequestParser

Inheritance

object

WebhookRequestParser

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.ReferenceEquals(object, object)

object.ToString()

Constructors

WebhookRequestParser(string)

public WebhookRequestParser(string channelSecret)

Parameters

channelSecret string

The channel secret (the key for signature validation).

Exceptions

ArgumentException

channelSecret is empty or whitespace only.

Methods

ParseAsync(byte[], string?, CancellationToken)

Validates the signature with the channel secret supplied at construction and deserializes the body into Line.OpenApi.Messaging.Webhook.Generated.Models.CallbackRequest.

public Task<CallbackRequest> ParseAsync(byte[] body, string? signatureHeader, CancellationToken cancellationToken = default)

Parameters

body byte[]

The raw request body (both signature validation and deserialization operate on these same bytes).

signatureHeader string

The x-line-signature header value.

cancellationToken CancellationToken

Cancellation token.

Returns

Task<CallbackRequest>

Exceptions

ArgumentNullException

body is null.

WebhookSignatureException

Signature validation failed.

WebhookPayloadException

The signature was valid but the body could not be deserialized.

ParseAsync(string, byte[], string?, CancellationToken)

Validates the signature and deserializes the body, specifying the channel secret per call (for multi-tenant scenarios).

public static Task<CallbackRequest> ParseAsync(string channelSecret, byte[] body, string? signatureHeader, CancellationToken cancellationToken = default)

Parameters

channelSecret string

body byte[]

signatureHeader string

cancellationToken CancellationToken

Returns

Task<CallbackRequest>

Exceptions

ArgumentNullException

body is null.

ArgumentException

channelSecret is empty or whitespace only.

WebhookSignatureException

Signature validation failed.

WebhookPayloadException

The signature was valid but the body could not be deserialized.