Jhwang/add ability to modify partition

service/src/main/kotlin/app/cash/backfila/dashboard/BackfilaWebActionsModule.kt

@@ -17,5 +17,7 @@ class BackfilaWebActionsModule() : KAbstractModule() {
     install(WebActionModule.create<GetBackfillStatusAction>())
     install(WebActionModule.create<UpdateBackfillAction>())
     install(WebActionModule.create<ViewLogsAction>())
+    install(WebActionModule.create<EditPartitionCursorAction>())
+    install(WebActionModule.create<EditPartitionCursorHandlerAction>())
   }
 }

service/src/main/kotlin/app/cash/backfila/dashboard/EditPartitionCursorAction.kt

@@ -0,0 +1,150 @@
+package app.cash.backfila.dashboard
+
+import app.cash.backfila.ui.components.DashboardPageLayout
+import app.cash.backfila.ui.pages.BackfillShowAction
+import javax.inject.Inject
+import javax.inject.Singleton
+import kotlinx.html.ButtonType
+import kotlinx.html.FormMethod
+import kotlinx.html.InputType
+import kotlinx.html.a
+import kotlinx.html.button
+import kotlinx.html.div
+import kotlinx.html.form
+import kotlinx.html.h1
+import kotlinx.html.input
+import kotlinx.html.label
+import kotlinx.html.p
+import misk.security.authz.Authenticated
+import misk.tailwind.Link
+import misk.web.Get
+import misk.web.PathParam
+import misk.web.Response
+import misk.web.ResponseBody
+import misk.web.ResponseContentType
+import misk.web.actions.WebAction
+import misk.web.mediatype.MediaTypes
+
+@Singleton
+class EditPartitionCursorAction @Inject constructor(
+  private val getBackfillStatusAction: GetBackfillStatusAction,
+  private val dashboardPageLayout: DashboardPageLayout,
+) : WebAction {
+
+  @Get(PATH)
+  @ResponseContentType(MediaTypes.TEXT_HTML)
+  @Authenticated(capabilities = ["users"])
+  fun get(
+    @PathParam id: Long,
+    @PathParam partitionName: String,
+  ): Response<ResponseBody> {
+    val backfill = getBackfillStatusAction.status(id)
+
+    val partition = backfill.partitions.find { it.name == partitionName }
+      ?: throw IllegalArgumentException("Partition not found")
+
+    // Take a snapshot of current cursor for validation
+    val cursorSnapshot = partition.pkey_cursor
+
+    return Response(
+      dashboardPageLayout.newBuilder()
+        .title("Edit Cursor - Partition $partitionName")
+        .breadcrumbLinks(
+          Link("Backfill #$id", BackfillShowAction.path(id)),
+          Link("Edit Cursor", path(id, partitionName)),
+        )
+        .buildHtmlResponseBody {
+          div("space-y-6 max-w-2xl mx-auto py-8") {
+            h1("text-xl font-semibold") {
+              +"Edit Cursor for Partition: $partitionName"
+            }
+
+            div("rounded-md bg-yellow-50 p-4 mb-6") {
+              div("flex") {
+                div("flex-shrink-0") {
+                  // Warning icon
+                  div("h-5 w-5 text-yellow-400") {
+                    +"⚠️"
+                  }
+                }
+                div("ml-3") {
+                  h1("text-sm font-medium text-yellow-800") {
+                    +"Warning: Editing cursors can be dangerous"
+                  }
+                  div("mt-2 text-sm text-yellow-700") {
+                    p {
+                      +"Make sure you understand the implications of changing the cursor position. Records between the old and new cursor positions may be skipped or processed multiple times."
+                    }
+                  }
+                }
+              }
+            }
+
+            form {
+              method = FormMethod.get
+              action = EditPartitionCursorHandlerAction.path(id, partitionName)
+
+              input {
+                type = InputType.hidden
+                name = "cursor_snapshot"
+                value = cursorSnapshot ?: ""
+              }
+
+              div("space-y-4") {
+                div {
+                  label("block text-sm font-medium text-gray-700") {
+                    htmlFor = "current_cursor"
+                    +"Current Cursor"
+                  }
+                  div("mt-1") {
+                    input(classes = "block w-full rounded-md border-0 py-1.5 text-gray-900 shadow-sm ring-1 ring-inset ring-gray-300 placeholder:text-gray-400 focus:ring-2 focus:ring-inset focus:ring-indigo-600 sm:text-sm sm:leading-6") {
+                      type = InputType.text
+                      attributes["id"] = "current_cursor"
+                      value = cursorSnapshot ?: "Not started"
+                      disabled = true
+                    }
+                  }
+                }
+
+                div {
+                  label("block text-sm font-medium text-gray-700") {
+                    htmlFor = "new_cursor"
+                    +"New Cursor"
+                  }
+                  div("mt-1") {
+                    input(classes = "block w-full rounded-md border-0 py-1.5 text-gray-900 shadow-sm ring-1 ring-inset ring-gray-300 placeholder:text-gray-400 focus:ring-2 focus:ring-inset focus:ring-indigo-600 sm:text-sm sm:leading-6") {
+                      type = InputType.text
+                      name = "new_cursor"
+                      attributes["id"] = "new_cursor"
+                      value = cursorSnapshot ?: ""
+                      required = true
+                    }
+                  }
+                  p("mt-2 text-sm text-gray-500") {
+                    +"Enter the new cursor value. This must be a valid UTF-8 string."
+                  }
+                }
+
+                div("flex justify-end gap-3") {
+                  a(href = BackfillShowAction.path(id), classes = "rounded-md bg-white px-3 py-2 text-sm font-semibold text-gray-900 shadow-sm ring-1 ring-inset ring-gray-300 hover:bg-gray-50") {
+                    +"Cancel"
+                  }
+                  button(classes = "rounded-md bg-indigo-600 px-3 py-2 text-sm font-semibold text-white shadow-sm hover:bg-indigo-500 focus-visible:outline focus-visible:outline-2 focus-visible:outline-offset-2 focus-visible:outline-indigo-600") {
+                    type = ButtonType.submit
+                    +"Update Cursor"
+                  }
+                }
+              }
+            }
+          }
+        },
+    )
+  }
+
+  companion object {
+    private const val PATH = "/backfills/{id}/{partitions}/{partitionName}/edit-cursor"
+    fun path(id: Long, partitionName: String) = PATH
+      .replace("{id}", id.toString())
+      .replace("{partitionName}", partitionName)
+  }
+}

service/src/main/kotlin/app/cash/backfila/dashboard/EditPartitionCursorHandlerAction.kt

@@ -0,0 +1,91 @@
+package app.cash.backfila.dashboard
+
+import app.cash.backfila.service.persistence.BackfilaDb
+import app.cash.backfila.service.persistence.BackfillState
+import app.cash.backfila.service.persistence.RunPartitionQuery
+import app.cash.backfila.ui.pages.BackfillShowAction
+import javax.inject.Inject
+import javax.inject.Singleton
+import misk.exceptions.BadRequestException
+import misk.hibernate.Query
+import misk.hibernate.Transacter
+import misk.hibernate.newQuery
+import misk.scope.ActionScoped
+import misk.security.authz.Authenticated
+import misk.web.Get
+import misk.web.HttpCall
+import misk.web.PathParam
+import misk.web.Response
+import misk.web.ResponseBody
+import misk.web.ResponseContentType
+import misk.web.actions.WebAction
+import misk.web.mediatype.MediaTypes
+import misk.web.toResponseBody
+import okhttp3.Headers
+import okio.ByteString.Companion.encodeUtf8
+
+@Singleton
+class EditPartitionCursorHandlerAction @Inject constructor(
+  private val getBackfillStatusAction: GetBackfillStatusAction,
+  @BackfilaDb private val transacter: Transacter,
+  private val queryFactory: Query.Factory,
+  private val httpCall: ActionScoped<HttpCall>,
+) : WebAction {
+
+  @Get(PATH)
+  @ResponseContentType(MediaTypes.TEXT_HTML)
+  @Authenticated(capabilities = ["users"])
+  fun get(
+    @PathParam id: Long,
+    @PathParam partitionName: String,
+  ): Response<ResponseBody> {
+    val request = httpCall.get().asOkHttpRequest()
+    val cursorSnapshot = request.url.queryParameter("cursor_snapshot")?.takeIf { it.isNotBlank() }
+    val newCursor = request.url.queryParameter("new_cursor")
+
+    // Validate UTF-8
+    try {
+      newCursor?.toByteArray(Charsets.UTF_8)?.toString(Charsets.UTF_8)
+    } catch (e: Exception) {
+      throw BadRequestException("New cursor must be valid UTF-8")
+    }
+
+    // Verify backfill state and cursor hasn't changed
+    val backfill = getBackfillStatusAction.status(id)
+    if (backfill.state != BackfillState.PAUSED) {
+      throw BadRequestException("Backfill must be paused to edit cursors")
+    }
+
+    val partition = backfill.partitions.find { it.name == partitionName }
+      ?: throw BadRequestException("Partition not found")
+
+    if (partition.pkey_cursor != cursorSnapshot) {
+      throw BadRequestException("Cursor has changed since edit form was loaded")
+    }
+
+    // Update the cursor
+    transacter.transaction { session ->
+      queryFactory.newQuery<RunPartitionQuery>()
+        .partitionId(partition.id)
+        .uniqueResult(session)
+        ?.let { partitionRecord ->
+          partitionRecord.pkey_cursor = newCursor?.encodeUtf8()
+          session.save(partitionRecord)
+        } ?: throw BadRequestException("Partition not found")
+    }
+
+    // Redirect to backfill page
+    return Response(
+      body = "go to ${BackfillShowAction.path(id)}".toResponseBody(),
+      statusCode = 303,
+      headers = Headers.headersOf("Location", BackfillShowAction.path(id)),
+    )
+  }
+
+  companion object {
+    private const val PATH = "/backfills/{id}/{partitionName}/edit-cursor"
+    fun path(id: Long, partitionName: String) = PATH
+      .replace("{id}", id.toString())
+      .replace("{partitionName}", partitionName)
+  }
+}

service/src/main/kotlin/app/cash/backfila/service/persistence/RunPartitionQuery.kt

@@ -22,4 +22,7 @@ interface RunPartitionQuery : Query<DbRunPartition> {
 
   @Order("partition_name")
   fun orderByName(): RunPartitionQuery
+
+  @Constraint("id", Operator.EQ)
+  fun partitionId(partitionId: Long): RunPartitionQuery
 }

service/src/main/kotlin/app/cash/backfila/ui/pages/BackfillShowAction.kt

@@ -1,5 +1,6 @@
 package app.cash.backfila.ui.pages
 
+import app.cash.backfila.dashboard.EditPartitionCursorAction
 import app.cash.backfila.dashboard.GetBackfillStatusAction
 import app.cash.backfila.dashboard.GetBackfillStatusResponse
 import app.cash.backfila.dashboard.ViewLogsAction
@@ -161,6 +162,12 @@ class BackfillShowAction @Inject constructor(
                     scope = ThScope.col
                     +"""ETA"""
                   }
+                  if (backfill.state == BackfillState.PAUSED) {
+                    th(classes = "py-3 pl-8 pr-0 text-right font-semibold") {
+                      scope = ThScope.col
+                      +"""Actions"""
+                    }
+                  }
                 }
               }
               tbody {
@@ -202,6 +209,16 @@ class BackfillShowAction @Inject constructor(
                         }
                       }
                     }
+                    if (backfill.state == BackfillState.PAUSED) {
+                      td("py-5 pl-8 pr-0 text-right align-top") {
+                        a(
+                          href = EditPartitionCursorAction.path(id, partition.name),
+                          classes = "text-indigo-600 hover:text-indigo-900",
+                        ) {
+                          +"Edit Cursor"
+                        }
+                      }
+                    }
                   }
                 }
               }