从IntegrationFlows返回ObjectNode时的奇怪行为

Question

 @Bean
public IntegrationFlow extractFramesFlow() {
    return IntegrationFlows.from(extractFramesChannel())
            .handle(ObjectNode.class, (payload, headers) -> {
        payload = validateFields(payload);
        String path = payload.get("path").asText();
        try {
            File moviePath = new File(path);
            ArrayNode arrayNode = mapper.createArrayNode();
            String imageType = payload.path("image_type").asText("JPG");
            String prefix = payload.path("prefix").asText();
            Tools.thumbnails(moviePath, payload.get("slice").asInt(), payload.get("scale").asInt(),
                    imageType, prefix, file -> arrayNode.add(file.toString()));
            payload.set("files", arrayNode);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return payload;
    }).enrichHeaders(h-> h.header("errorChannel", "asyncErrorChannel", true))
            .<ObjectNode, Boolean>route(p-> !p.hasNonNull("id"),
            m->m.channelMapping("true","httpCallbackFlow.input")
                    .channelMapping("false","uploadToS3Channel")).get();
}

@Bean
public IntegrationFlow httpCallbackFlow() {
    return f->f.handle(Http.<JsonNode>outboundChannelAdapter(m->m.getPayload().get("call_back").asText()));
}

但是，当从handleAsyncErrors（）流链接ObjectNode并到达相同的httpCallbackFlow（）时，我们会得到一个异常，该异常由

restClientException：无法写入请求：在org.springframework.web.client.restTemplate$HttpEntityRequestCallback.dowithRequest(restTemplate.java:811)在org.springframework.web.client.restTemplate.doExecute(restTemplate.java:594)在org.springframework.web.client.restTemplate.execute(restTemplate.java:572)在Java:493)在org.springframework.integration.http.outbound.HttpRequestExecutingMessageHandler.HandleRequestMessage(HttpRequestExecutingMessageHandler.java:382)...24多

@Bean
public IntegrationFlow handleAsyncErrors() {
    return IntegrationFlows.from(asyncErrorChannel())
            .<MessagingException>handle((p, h) -> {
                ObjectNode objectNode = mapper.createObjectNode();
                objectNode.put("call_back", "http://some.test.uri");
                return objectNode;
            }).channel("httpCallbackFlow.input").get();
}

我不知道为什么这个异常会被完全相同的IntegrationFlow处理。

Answer 1

错误流上的消息没有ContentType标头。

它是带有MessagingException有效负载的错误消息；具有2个性质；原因和失败消息。

大概您在主流消息上有一个内容类型。您可以使用标题enricher设置内容类型，或添加

.<MessagingException, Message<?>>transform(p -> p.getFailedMessage())