fix(translator): shape Anthropic non-stream responses from forced-streaming providers

The non-streaming Anthropic path leaked OpenAI chat.completion bodies to Claude clients when the upstream provider forces streaming (forced SSE->JSON path): parseSSEToOpenAIResponse yields choices[] which Claude Code cannot parse. Convert to Claude Messages shape for sourceFormat CLAUDE in sseToJsonHandler. Shared toClaudeMessageShape/openAICompletionToClaudeMessage moved to translator/concerns/claudeShape.js to avoid circular import between nonStreamingHandler and sseToJsonHandler. 5 new tests: sse-to-json reassembly + Claude guard, plus existing anthropic-nonstream-shape updated to import from the concern.
2026-09-23 15:36:24 +07:00
parent b239b2a8a9
commit 3de32a10f3
5 changed files with 139 additions and 67 deletions
@@ -0,0 +1,74 @@
+import { FORMATS } from "../formats.js";
+import { fromOpenAIFinish } from "./finishReason.js";
+
+// Shared OpenAI-Chat → Claude-Messages shape conversion.
+//
+// Lives in `concerns/` (not chatCore/) because BOTH the non-streaming handler
+// and the forced-SSE→JSON handler need it, and importing it from
+// nonStreamingHandler.js into sseToJsonHandler.js would create a circular
+// import (nonStreamingHandler already imports parseSSEToOpenAIResponse from
+// sseToJsonHandler).
+
+function parseToolArguments(value) {
+  if (!value) return {};
+  if (typeof value === "object") return value;
+  try {
+    return JSON.parse(value);
+  } catch {
+    return {};
+  }
+}
+
+function openAICompletionToClaudeMessage(responseBody) {
+  if (!responseBody?.choices?.[0]) return responseBody;
+  const choice = responseBody.choices[0];
+  const message = choice.message || {};
+  const content = [];
+
+  const reasoning = message.reasoning_content || message.provider_specific_fields?.reasoning_content || "";
+  if (reasoning) {
+    content.push({ type: "thinking", thinking: reasoning });
+  }
+  if (typeof message.content === "string" && message.content.length > 0) {
+    content.push({ type: "text", text: message.content });
+  }
+  for (const toolCall of message.tool_calls || []) {
+    const fn = toolCall.function || {};
+    content.push({
+      type: "tool_use",
+      id: toolCall.id || `toolu_${Date.now()}_${content.length}`,
+      name: fn.name || toolCall.name || "",
+      input: parseToolArguments(fn.arguments || toolCall.arguments),
+    });
+  }
+  if (content.length === 0) content.push({ type: "text", text: "" });
+
+  const usage = responseBody.usage || {};
+  return {
+    id: String(responseBody.id || `msg_${Date.now()}`).replace(/^chatcmpl-/, ""),
+    type: "message",
+    role: "assistant",
+    model: responseBody.model || "unknown",
+    content,
+    stop_reason: fromOpenAIFinish(choice.finish_reason, FORMATS.CLAUDE),
+    stop_sequence: null,
+    usage: {
+      input_tokens: usage.prompt_tokens || usage.input_tokens || 0,
+      output_tokens: usage.completion_tokens || usage.output_tokens || 0,
+    },
+  };
+}
+
+/**
+ * Convert an OpenAI Chat Completions body into the Claude Messages shape when
+ * the client speaks Anthropic (sourceFormat=CLAUDE) but the provider replied
+ * OpenAI JSON. Shape-aware guard: Claude-shaped bodies pass through untouched.
+ */
+export function toClaudeMessageShape(responseBody) {
+  if (!responseBody || responseBody.type === "message") return responseBody;
+  if (responseBody?.choices) return openAICompletionToClaudeMessage(responseBody);
+  return responseBody;
+}
+
+/** Export the raw converter for tests that want it directly. */
+export { openAICompletionToClaudeMessage };