Events API Send-RSVP support (#175)

- Events API Send-RSVP support

# License
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src/main/kotlin/com/nylas/models/RsvpStatus.kt

@@ -0,0 +1,17 @@
+package com.nylas.models
+
+import com.squareup.moshi.Json
+
+/**
+ * Enum representing the allowed RSVP status values.
+ */
+enum class RsvpStatus {
+  @Json(name = "yes")
+  YES,
+
+  @Json(name = "no")
+  NO,
+
+  @Json(name = "maybe")
+  MAYBE,
+}

src/main/kotlin/com/nylas/models/SendRsvpQueryParams.kt

@@ -0,0 +1,28 @@
+package com.nylas.models
+
+import com.squareup.moshi.Json
+
+/**
+ * Class representation of the query parameters for sending RSVP.
+ */
+data class SendRsvpQueryParams(
+  /**
+   * The RSVP status for the event. Must be yes, no, or maybe
+   */
+  @Json(name = "status")
+  val status: RsvpStatus
+) : IQueryParams {
+
+  /**
+   * Builder for [SendRsvpQueryParams].
+   * @param status The RSVP status for the event. Must be yes, no, or maybe
+   */
+  data class Builder(private val status: RsvpStatus) {
+
+    /**
+     * Builds a [SendRsvpQueryParams] instance.
+     * @return The [SendRsvpQueryParams] instance.
+     */
+    fun build() = SendRsvpQueryParams(status)
+  }
+}

src/main/kotlin/com/nylas/models/SendRsvpRequest.kt

@@ -0,0 +1,14 @@
+package com.nylas.models
+
+import com.squareup.moshi.Json
+
+/**
+ * Class representation of a Nylas send-rsvp request
+ */
+data class SendRsvpRequest(
+  /**
+   * RSVP status. must be yes, no, or maybe
+   */
+  @Json(name = "status")
+  val status: RsvpStatus,
+)

src/main/kotlin/com/nylas/resources/Events.kt

@@ -80,4 +80,21 @@ class Events(client: NylasClient) : Resource<Event>(client, Event::class.java) {
     val path = String.format("v3/grants/%s/events/%s", identifier, eventId)
     return destroyResource(path, queryParams)
   }
+
+  /**
+   * Send RSVP. Allows users to respond to events they have been added to as an attendee.
+   * @param identifier The identifier of the grant to act upon
+   * @param eventId The id of the Event to update.
+   * @param requestBody The values to send the RSVP with
+   * @param queryParams The query parameters to include in the request
+   * @return The send-rsvp response
+   */
+  @Throws(NylasApiError::class, NylasSdkTimeoutError::class)
+  fun sendRsvp(identifier: String, requestBody: SendRsvpRequest, queryParams: SendRsvpQueryParams): DeleteResponse{
+    val path = String.format("v3/grants/%s/events/%s/send-rsvp", identifier, eventId)
+    val adapter = JsonHelper.moshi().adapter(SendRsvpRequest::class.java)
+    val serializedRequestBody = adapter.toJson(requestBody)
+    return createResource(path, serializedRequestBody, queryParams)
+  }
+
 }