javascript - Ditto.asByteBuffer(bytePayload) 抛出异常

Question

在eclipse-ditto mappingcontext 我放置在 incomingScript 之后:

function mapToDittoProtocolMsg(headers, textPayload, bytePayload, contentType) {
switch (contentType) {
    case "application/json":
        var jsonData = JSON.parse(textPayload);
        var temperature = jsonData.temp;
        var humidity = jsonData.hum;
        var path;
        var value;
        if (temperature != null && humidity != null) {
            path = "/features";
            value = {
                temperature: {
                    properties: {
                        value: temperature
                    }
                },
                humidity: {
                    properties: {
                        value: humidity
                    }
                }
            };
        } else if (temperature != null) {
            path = "/features/temperature/properties/value";
            value = temperature;
        } else if (humidity != null) {
            path = "/features/humidity/properties/value";
            value = humidity;
        }
        if (!path || !value) {
            return null;
        }
        return Ditto.buildDittoProtocolMsg("tenant_aloxy", headers["device_id"], "things", "twin", "commands", "modify", path, headers, value);
        break;
    case "application/octet-stream":
        let byteBuf = Ditto.asByteBuffer(bytePayload);
        var path = "/features/alp/properties/value";
        var value = 21;
        return Ditto.buildDittoProtocolMsg("tenant_aloxy", headers["device_id"], "things", "twin", "commands", "modify", path, headers, value);
    default:
        return null;
}

当我发送二进制数据时，我按预期点击了开关的第二种情况。但是，当它尝试将传入数据转换为字节缓冲区时 (Ditto.asByteBuffer(bytePayload);)，它会抛出以下异常:

ReferenceError: "dcodeIO" is not defined.

Answer 1

“同上”范围内的辅助函数需要“ByteBuffer.js”库，如文档中所述:https://www.eclipse.org/ditto/connectivity-mapping.html#bytebufferjs (dcodeIO 用作该库的范围)。

这意味着您只需在您的映射配置中启用此库加载:https://www.eclipse.org/ditto/connectivity-mapping.html#configuration-options

{
  "incomingScript": "...",
  "outgoingScript": "...",
  "loadBytebufferJS": true,
  "loadLongJS": true
}

之后你应该可以使用 Ditto.asByteBuffer()