GraphSearchStreaming

另请参阅

• GraphQueryStreamingResult
• knowledgeGraphService

// example GraphSearchStreaming used in a executeSearchStreaming
KnowledgeGraphModule.executeSearchStreaming(
  knowledgeGraph,
  { // autocasts to new GraphSearchStreaming
    searchQuery: "solar",
    typeCategoryFilter: "both",
    returnSearchContext: false,
    start: 1, // index of first record to return
    num: 200, // return 200 records.
    namedTypesFilter: ["Company", "Supplier", "Part"],
    globalIdsFilter: ["{G4E8G2S8D-2GS5-98S4-3S5D-S1DE7G45DS48}",
                     "{FNWI1G5W-1A5W-3A5W-8412-A1W5F4W8F7AS}",
                     "{9D2D6AFD-41F1-49A4-8412-CACCC9906E88}"]
  }
).then((streamingSearchResult)=>{
  // the result of a streaming search is a readableStream which requires decoding.
  readStream(streamingSearchResult)
})

// a function to read the readable stream returned from the above query
const readStream = async (streamingQueryResult) => {
  let time = Date.now();
  let reader = streamingQueryResult.resultRowsStream.getReader();
  try {
    while (true) {
      const { done, value } = await reader.read();
      if (done) {
        console.log(`Completed database requests: ${(Date.now() - time) / 1000} seconds`, value);
        break;
      }
      console.log(`Chunk returned in: ${(Date.now() - time) / 1000} seconds`, value)
    }
  } catch (err) {
    if (err.name === "AbortError") {
      console.log("Request aborted as expected");
    } else {
      throw err;
    }
  }
};

// sample result of read streaming search result chunk printed to the console
"Streaming chunk returned in: 0.082 seconds"
[
  [{
    "declaredClass": "geoscene.rest.knowledgeGraph.Entity",
    "properties": {
      "Name": "Suncommon",
      "Employee_Count": 400,
      "energyType": "solar"
    },
    "typeName": "Company",
    "id": "{G4E8G2S8D-2GS5-98S4-3S5D-S1DE7G45DS48}"
  }],
  [{
    "declaredClass": "geoscene.rest.knowledgeGraph.Entity",
    "properties": {
      "Name": "Quality Solar Supply",
      "Supplier_code": "158B",
      "City": "New Orleans",
    },
    "typeName": "Supplier",
    "id": "{FNWI1G5W-1A5W-3A5W-8412-A1W5F4W8F7AS}"
  }],
  [{
    "declaredClass": "geoscene.rest.knowledgeGraph.Entity",
    "properties": {
      "Name": "Solar panel",
      "panel_type": "Polycrystalline",
      "price_per_unit": 400
    },
    "typeName": "Part",
    "id": "{9D2D6AFD-41F1-49A4-8412-CACCC9906E88}"
  }]
]

构造函数

new GraphSearchStreaming(properties)

参数

properties Object optional 有关所有属性的列表，请参阅 properties。