fix: avoid long channel pagination urls

Author: Priveetee

openapi.yaml

@@ -21,6 +21,8 @@ paths:
     $ref: ./openapi/paths/search.yaml#/Search
   /channel:
     $ref: ./openapi/paths/channel.yaml#/Channel
+  /channel/page:
+    $ref: ./openapi/paths/channel.yaml#/ChannelPage
   /podcasts:
     $ref: ./openapi/paths/podcasts.yaml#/Podcasts
   /podcasts/episodes:
@@ -55,6 +57,8 @@ components:
       $ref: ./openapi/components/media.yaml#/SearchPageResponse
     ChannelResponse:
       $ref: ./openapi/components/media.yaml#/ChannelResponse
+    ChannelPageRequest:
+      $ref: ./openapi/components/media.yaml#/ChannelPageRequest
     PodcastPageResponse:
       $ref: ./openapi/components/media.yaml#/PodcastPageResponse
     PodcastEpisodesResponse:

openapi/components/media.yaml

@@ -38,6 +38,16 @@ ChannelResponse:
     isVerified: { type: boolean }
     videos: { type: array, items: { $ref: '#/VideoItem' } }
     nextpage: { type: string, nullable: true }
+ChannelPageRequest:
+  type: object
+  required: [url]
+  properties:
+    url: { type: string }
+    nextpage: { type: string, nullable: true }
+    sort:
+      type: string
+      nullable: true
+      enum: [latest, popular, oldest]
 PodcastItem:
   type: object
   required: [id, title, url, thumbnailUrl, uploaderName, streamCount, playlistType]

openapi/paths/channel.yaml

@@ -31,3 +31,27 @@ Channel:
         $ref: ../components/common.yaml#/JsonError
       '422':
         $ref: ../components/common.yaml#/JsonError
+ChannelPage:
+  post:
+    tags: [extraction]
+    summary: Get channel metadata and videos with pagination cursor in JSON body
+    requestBody:
+      required: true
+      content:
+        application/json:
+          schema:
+            $ref: ../components/media.yaml#/ChannelPageRequest
+    responses:
+      '200':
+        description: Channel metadata and video page.
+        headers:
+          X-Request-ID:
+            $ref: ../components/common.yaml#/RequestIdHeader
+        content:
+          application/json:
+            schema:
+              $ref: ../components/media.yaml#/ChannelResponse
+      '400':
+        $ref: ../components/common.yaml#/JsonError
+      '422':
+        $ref: ../components/common.yaml#/JsonError

src/main/kotlin/dev/typetype/server/models/ChannelPageRequest.kt

@@ -0,0 +1,10 @@
+package dev.typetype.server.models
+
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class ChannelPageRequest(
+    val url: String? = null,
+    val nextpage: String? = null,
+    val sort: String? = null,
+)

src/main/kotlin/dev/typetype/server/routes/ChannelRoutes.kt

@@ -1,12 +1,17 @@
 package dev.typetype.server.routes
 
+import dev.typetype.server.models.ChannelPageRequest
+import dev.typetype.server.models.ChannelResponse
 import dev.typetype.server.models.ErrorResponse
 import dev.typetype.server.models.ExtractionResult
 import dev.typetype.server.services.ChannelService
 import io.ktor.http.HttpStatusCode
+import io.ktor.server.application.ApplicationCall
+import io.ktor.server.request.receive
 import io.ktor.server.response.respond
 import io.ktor.server.routing.Route
 import io.ktor.server.routing.get
+import io.ktor.server.routing.post
 
 fun Route.channelRoutes(channelService: ChannelService) {
     get("/channel") {
@@ -21,4 +26,25 @@ fun Route.channelRoutes(channelService: ChannelService) {
             is ExtractionResult.Failure -> call.respond(HttpStatusCode.UnprocessableEntity, ErrorResponse(result.message))
         }
     }
+    post("/channel/page") {
+        val request = call.receive<ChannelPageRequest>()
+        val url = request.url?.takeIf { it.isNotBlank() }
+            ?: return@post call.respond(HttpStatusCode.BadRequest, ErrorResponse("Missing 'url' parameter"))
+
+        call.respondChannelResult(
+            channelService.getChannel(
+                url = url,
+                nextpage = request.nextpage?.takeIf { it.isNotBlank() },
+                sort = request.sort?.takeIf { it.isNotBlank() },
+            )
+        )
+    }
+}
+
+private suspend fun ApplicationCall.respondChannelResult(result: ExtractionResult<ChannelResponse>) {
+    when (result) {
+        is ExtractionResult.Success -> respond(result.data)
+        is ExtractionResult.BadRequest -> respond(HttpStatusCode.BadRequest, ErrorResponse(result.message))
+        is ExtractionResult.Failure -> respond(HttpStatusCode.UnprocessableEntity, ErrorResponse(result.message))
+    }
 }

src/test/kotlin/dev/typetype/server/ChannelRoutesTest.kt

@@ -5,7 +5,11 @@ import dev.typetype.server.models.ExtractionResult
 import dev.typetype.server.routes.channelRoutes
 import dev.typetype.server.services.ChannelService
 import io.ktor.client.request.get
+import io.ktor.client.request.header
+import io.ktor.client.request.post
+import io.ktor.client.request.setBody
 import io.ktor.http.HttpStatusCode
+import io.ktor.http.HttpHeaders
 import io.ktor.serialization.kotlinx.json.json
 import io.ktor.server.application.install
 import io.ktor.server.plugins.contentnegotiation.ContentNegotiation
@@ -80,4 +84,29 @@ class ChannelRoutesTest {
         assertEquals(HttpStatusCode.OK, response.status)
         coVerify { channelService.getChannel("https://www.youtube.com/@test/search?query=typing", null, null) }
     }
+
+    @Test
+    fun `POST channel page accepts long nextpage in body`() = withApp {
+        val nextpage = "x".repeat(9_000)
+        coEvery { channelService.getChannel(any(), any(), any()) } returns
+            ExtractionResult.Success(testChannelResponse())
+
+        val response = client.post("/channel/page") {
+            header(HttpHeaders.ContentType, "application/json")
+            setBody("""{"url":"https://youtube.com/channel/test","nextpage":"$nextpage","sort":"latest"}""")
+        }
+
+        assertEquals(HttpStatusCode.OK, response.status)
+        coVerify { channelService.getChannel("https://youtube.com/channel/test", nextpage, "latest") }
+    }
+
+    @Test
+    fun `POST channel page without url returns 400`() = withApp {
+        val response = client.post("/channel/page") {
+            header(HttpHeaders.ContentType, "application/json")
+            setBody("""{"nextpage":"cursor"}""")
+        }
+
+        assertEquals(HttpStatusCode.BadRequest, response.status)
+    }
 }