ノードを使用してGoogle Datastoreでエンティティデータを設定および受信する方法

Question

Googleデータストアからエンティティデータを設定して取得する方法がわかりません。私はさまざまな例を見つけて、どちらが正しいかを理解していません。以下は私がこれまで行ってきたことです。このエラーが発生し続ける：ReferenceError: datastore is not definedデータストアAPIを正しく呼び出さないのですか？

server.jsファイル：

var express = require('express'); 
var app = express(); 

const Datastore = require('@google-cloud/datastore'); 
const datastore = Datastore(); 

require('./routes/main')(app); 

require('@google/cloud-debug').start({ 
    keyFilename: './jarvis-hd-live-842e4f78479e.json' 
}); 

const PORT = process.env.PORT || 8080; 

app.listen(PORT,() => { 
    console.log(`Your app is listening on port ${PORT}`); 
}); 

ルートファイル：

app.post('/message', function (request, response) { 
    message = request.body.Body; 

    response.send("<Response><Message>Heyyo!</Message></Response>"); 

    const key = datastore.key('timestamp'); 

    datastore.save({ 
    key: key, 
    data : { 
     timestamp_value: 0 
    } 
    }); 


    datastore.insert(entity) 
     .then(()=> { 
      console.log("Data object inserted successfully."); 
     }); 

}); 

Answer 1

データストアSDKが適切な資格情報を使用して初期化/認証されていません。

server.jsがあるべき -

同じ行に

var express = require('express'); 
var app = express(); 
//The key file is required in a variable. The variable is now a JSON object with the credentials. 
var credentials = require('./jarvis-hd-live-842e4f78479e.json'); 
const Datastore = require('@google-cloud/datastore'); 
//Initialise the datastore object with the proper project id and credentials. 
const datastore = Datastore({ 
    projectId: "your_project_id_goes_here", 
    credentials: credentials 
}); 
/* 
* If you wish to give the filename instead of the credentials object while initialising, replace the credential key with keyFileName and the value with the file name of the key file. 
* Note: The key file should be in the same directory. If another directory, please provide absolute path. 
*/ 
require('./routes/main')(app); 
require('@google/cloud-debug').start({ 
    credentials: credentials 
}); 
const PORT = process.env.PORT || 8080; 

app.listen(PORT,() => { 
    console.log(`Your app is listening on port ${PORT}`); 
}); 

、routes.jsは、次のようになります -

app.post('/message', function (request, response) { 
    message = request.body.Body; 

response.send("<Response><Message>Heyyo!</Message></Response>"); 

//While getting a key for an object, you need to mention the namespace on which your kind resides.(Kind can be thought of as a table.) 
const key = datastore.key({ 
    namespace: "your_namespace_goes_here", 
    path: ["kind_name_goes_here","explicit_name/id_of_the_object"] 
}); 
/* 
* If the name/id is kept null in the path key, datastore will assign a numeric id to the key. 
* The name should be set if the application uses some kind of custom naming/identification scheme using UUID/GUID. 
*/ 
datastore.save({ 
    key: key, 
    data : { 
     timestamp_value: 0 
    } 
}); 
datastore.insert(entity) 
    .then(()=> { 
     console.log("Data object inserted successfully."); 
    }); 
});