feat: 添加流式支持；教材知识库 Demo

utils/http.ts

@@ -0,0 +1,84 @@
+export const http_stream = async <ReqT>(
+  url: string,
+  params: ReqT,
+  events: {
+    onStart?: (id: string, created_at?: number, messageId?: string | null) => void
+    onTextChunk?: (message: string) => void
+    onComplete?: (id: string | null, finished_at?: number, messageId?: string | null) => void
+  }) => {
+  const { onStart, onTextChunk, onComplete } = events
+
+  const runtimeConfig = useRuntimeConfig()
+
+  const response = await fetch(url, {
+    method: 'POST',
+    headers: {
+      'Content-Type': 'application/json',
+      'Authorization': `Bearer ${runtimeConfig.public.DifyApiKey}`,
+    },
+    body: JSON.stringify(params),
+  })
+
+  if (!response) {
+    throw new Error('Network response was not ok')
+  }
+
+  const reader = response.body?.getReader()
+  const decoder = new TextDecoder('utf-8')
+  let buffer = ''
+
+  while (true) {
+    const { done, value } = await reader?.read() || {}
+    if (done) break
+
+    buffer += decoder.decode(value, { stream: true })
+
+    const parts = buffer.split('\n\n')
+    buffer = parts.pop()!
+
+    for (const part of parts) {
+      if (!part.trim().startsWith('data:')) continue
+      const payload = part.replace(/^data:\s*/, '').trim()
+
+      try {
+        const obj = JSON.parse(payload)
+        if (obj?.event && obj.event === 'workflow_started') {
+          onStart?.(obj?.data?.id || null, obj?.data?.created_at || 0, obj?.message_id || null)
+        }
+        if (obj?.event && obj.event === 'workflow_finished') {
+          onComplete?.(obj?.data?.id || null, obj?.data?.finished_at || 0, obj?.message_id || null)
+          return
+        }
+        // Workflow
+        if (obj?.event && obj.event === 'text_chunk') {
+          let text_chunk = obj.data?.text as string
+          if (text_chunk) {
+            if (text_chunk.startsWith('<') && text_chunk.endsWith('>')) {
+              const endTag = text_chunk.match(/<\/[^>]*>/)
+              if (endTag) {
+                text_chunk = text_chunk.replace(endTag[0], '\n' + endTag[0])
+              }
+            }
+            onTextChunk?.(text_chunk)
+          }
+        }
+        // Chatflow
+        if (obj?.event && obj.event === 'message') {
+          let ans = obj.answer
+          if (ans) {
+            if (ans.startsWith('<') && ans.endsWith('>')) {
+              const endTag = ans.match(/<\/[^>]*>/)
+              if (endTag) {
+                ans = ans.replace(endTag[0], '\n' + endTag[0])
+              }
+            }
+            onTextChunk?.(ans)
+          }
+        }
+      } catch {
+        // ignore
+      }
+    }
+  }
+  onComplete?.(null)
+}