inital upload

node_modules/eventsource-parser/src/stream.ts

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+import {createParser} from './parse.ts'
+import type {EventSourceMessage, EventSourceParser} from './types.ts'
+
+/**
+ * Options for the EventSourceParserStream.
+ *
+ * @public
+ */
+export interface StreamOptions {
+  /**
+   * Behavior when a parsing error occurs.
+   *
+   * - A custom function can be provided to handle the error.
+   * - `'terminate'` will error the stream and stop parsing.
+   * - Any other value will ignore the error and continue parsing.
+   *
+   * @defaultValue `undefined`
+   */
+  onError?: 'terminate' | ((error: Error) => void)
+
+  /**
+   * Callback for when a reconnection interval is sent from the server.
+   *
+   * @param retry - The number of milliseconds to wait before reconnecting.
+   */
+  onRetry?: (retry: number) => void
+
+  /**
+   * Callback for when a comment is encountered in the stream.
+   *
+   * @param comment - The comment encountered in the stream.
+   */
+  onComment?: (comment: string) => void
+}
+
+/**
+ * A TransformStream that ingests a stream of strings and produces a stream of `EventSourceMessage`.
+ *
+ * @example Basic usage
+ * ```
+ * const eventStream =
+ *   response.body
+ *     .pipeThrough(new TextDecoderStream())
+ *     .pipeThrough(new EventSourceParserStream())
+ * ```
+ *
+ * @example Terminate stream on parsing errors
+ * ```
+ * const eventStream =
+ *  response.body
+ *   .pipeThrough(new TextDecoderStream())
+ *   .pipeThrough(new EventSourceParserStream({terminateOnError: true}))
+ * ```
+ *
+ * @public
+ */
+export class EventSourceParserStream extends TransformStream<string, EventSourceMessage> {
+  constructor({onError, onRetry, onComment}: StreamOptions = {}) {
+    let parser!: EventSourceParser
+
+    super({
+      start(controller) {
+        parser = createParser({
+          onEvent: (event) => {
+            controller.enqueue(event)
+          },
+          onError(error) {
+            if (onError === 'terminate') {
+              controller.error(error)
+            } else if (typeof onError === 'function') {
+              onError(error)
+            }
+
+            // Ignore by default
+          },
+          onRetry,
+          onComment,
+        })
+      },
+      transform(chunk) {
+        parser.feed(chunk)
+      },
+    })
+  }
+}
+
+export {type ErrorType, ParseError} from './errors.ts'
+export type {EventSourceMessage} from './types.ts'