快速入門:使用 Azure Cosmos DB Gremlin API 帳戶建置 Node.js 應用程式Quickstart: Build a Node.js application by using Azure Cosmos DB Gremlin API account

Azure Cosmos DB 是 Microsoft 的全域分散式多模型資料庫服務。Azure Cosmos DB is the globally distributed multimodel database service from Microsoft. 您可以快速建立及查詢文件、索引鍵/值及圖形資料庫,所有這些都受惠於位於 Azure Cosmos DB 核心的全域散發和水平調整功能。You can quickly create and query document, key/value, and graph databases, all of which benefit from the global distribution and horizontal scale capabilities at the core of Azure Cosmos DB.

本快速入門示範如何使用 Azure 入口網站建立 Azure Cosmos DB Gremlin API 帳戶、資料庫和圖表。This quickstart demonstrates how to create an Azure Cosmos DB Gremlin API account, database, and graph using the Azure portal. 您會接著使用開放原始碼 Gremlin Node.js 驅動程式來建置和執行主控台應用程式。You then build and run a console app by using the open-source Gremlin Node.js driver.

必要條件Prerequisites

您必須具備下列必要條件,才能執行此範例:Before you can run this sample, you must have the following prerequisites:

如果您沒有 Azure 訂用帳戶,請在開始前建立免費帳戶If you don't have an Azure subscription, create a free account before you begin.

建立資料庫帳戶Create a database account

  1. 在新的瀏覽器視窗中,登入 Azure 入口網站In a new browser window, sign in to the Azure portal.

  2. 按一下 [建立資源] > [資料庫] > [Azure Cosmos DB] 。Click Create a resource > Databases > Azure Cosmos DB.

    Azure 入口網站的 [資料庫] 窗格

  3. 在 [建立 Azure Cosmos DB 帳戶] 頁面中,輸入新的 Azure Cosmos DB 帳戶的設定。In the Create Azure Cosmos DB Account page, enter the settings for the new Azure Cosmos DB account.

    設定Setting Value 說明Description
    訂用帳戶Subscription 您的訂用帳戶Your subscription 選取要用於此 Azure Cosmos DB 帳戶的 Azure 訂用帳戶。Select the Azure subscription that you want to use for this Azure Cosmos DB account.
    資源群組Resource Group 新建Create new

    然後輸入識別碼中所提供的同一個唯一名稱Then enter the same unique name as provided in ID
    選取 [建立新的] 。Select Create new. 然後為您的帳戶輸入新的資源群組名稱。Then enter a new resource-group name for your account. 為求簡化,請使用和識別碼相同的名稱。For simplicity, use the same name as your ID.
    帳戶名稱Account Name 輸入唯一名稱Enter a unique name 輸入唯一名稱來識別您的 Azure Cosmos DB 帳戶。Enter a unique name to identify your Azure Cosmos DB account. 因為 documents.azure.com 會附加到您所提供的識別碼以建立 URI,請使用唯一識別碼。Because documents.azure.com is appended to the ID that you provide to create your URI, use a unique ID.

    識別碼只能使用小寫字母、數字及連字號 (-) 字元。The ID can use only lowercase letters, numbers, and the hyphen (-) character. 長度必須介於 3 到 31 個字元之間。It must be between 3 and 31 characters in length.
    APIAPI Gremlin (圖形)Gremlin (graph) API 會決定要建立的帳戶類型。The API determines the type of account to create. Azure Cosmos DB 提供五個 API:Core(SQL) (適用於文件資料庫)、Gremlin (適用於圖形資料庫)、MongoDB (適用於文件資料庫)、「Azure 資料表」及 Cassandra。Azure Cosmos DB provides five APIs: Core(SQL) for document databases, Gremlin for graph databases, MongoDB for document databases, Azure Table, and Cassandra. 目前,您必須為每個 API 建立個別個帳戶。Currently, you must create a separate account for each API.

    選取 [Gremlin (圖形)] ,因為在此快速入門中,您會建立可搭配 Gremlin API 使用的資料表。Select Gremlin (graph) because in this quickstart you are creating a table that works with the Gremlin API.

    深入了解圖形 APILearn more about the Graph API.
    位置Location 選取最接近使用者的區域Select the region closest to your users 選取用來裝載 Azure Cosmos DB 帳戶的地理位置。Select a geographic location to host your Azure Cosmos DB account. 使用最接近使用者的位置,以便他們能以最快速度存取資料。Use the location that's closest to your users to give them the fastest access to the data.

    請選取 [檢閱 + 建立] 。Select Review+Create. 您可以略過 [網路] 和 [標記] 區段。You can skip the Network and Tags section.

    Azure Cosmos DB 的新帳戶刀鋒視窗

  4. 建立帳戶需要幾分鐘的時間。The account creation takes a few minutes. 等候入口網站顯示 [恭喜!已建立您的 Azure Cosmos DB 帳戶] 頁面。Wait for the portal to display the Congratulations! Your Azure Cosmos DB account was created page.

    Azure 入口網站的 [通知] 窗格

新增圖形Add a graph

您現在可以在 Azure 入口網站中使用 [資料總管] 工具,建立圖形資料庫。You can now use the Data Explorer tool in the Azure portal to create a graph database.

  1. 選取 [資料總管] > [新增圖形] 。Select Data Explorer > New Graph.

    [新增圖形] 區域會顯示在最右邊,您可能需要向右捲動才會看到。The Add Graph area is displayed on the far right, you may need to scroll right to see it.

    Azure 入口網站資料總管 [新增圖形] 頁面

  2. 在 [新增圖形] 頁面上,輸入新圖形的設定。In the Add graph page, enter the settings for the new graph.

    設定Setting 建議的值Suggested value 說明Description
    資料庫識別碼Database ID sample-databasesample-database 輸入 sample-database 作為新資料庫的名稱。Enter sample-database as the name for the new database. 資料庫名稱的長度必須介於 1 到 255 個字元,且不能包含 / \ # ? 或尾端空格。Database names must be between 1 and 255 characters, and cannot contain / \ # ? or a trailing space.
    ThroughputThroughput 400 RU400 RUs 將輸送量變更為每秒 400 個要求單位 (RU/秒)。Change the throughput to 400 request units per second (RU/s). 如果您想要降低延遲,稍後可以相應增加輸送量。If you want to reduce latency, you can scale up the throughput later.
    圖形識別碼Graph ID sample-graphsample-graph 輸入 sample-graph 作為新集合的名稱。Enter sample-graph as the name for your new collection. 圖形名稱與資料庫識別碼具有相同的字元需求。Graph names have the same character requirements as database IDs.
    資料分割索引鍵Partition Key /pk/pk 所有 Cosmos DB 帳戶都需要分割索引鍵,才能進行水準調整。All Cosmos DB accounts need a partition key to horizontally scale. 了解如何在圖表資料分割一文中選取適當的分割區索引鍵。Learn how to select an appropriate partition key in the Graph Data Partitioning article.
  3. 填妥表單後,選取 [確定] 。Once the form is filled out, select OK.

複製範例應用程式Clone the sample application

現在,我們將從 GitHub 複製 Gremlin API 應用程式、設定連接字串,然後加以執行。Now let's clone a Gremlin API app from GitHub, set the connection string, and run it. 您會看到,以程式設計方式來處理資料有多麼的容易。You'll see how easy it is to work with data programmatically.

  1. 開啟命令提示字元,建立名為 git-samples 的新資料夾,然後關閉命令提示字元。Open a command prompt, create a new folder named git-samples, then close the command prompt.

    md "C:\git-samples"
    
  2. 開啟 git 終端機視窗 (例如 git bash),並使用 cd 命令變更至要安裝範例應用程式的新資料夾。Open a git terminal window, such as git bash, and use the cd command to change to the new folder to install the sample app.

    cd "C:\git-samples"
    
  3. 執行下列命令來複製範例存放庫。Run the following command to clone the sample repository. 此命令會在您的電腦上建立範例應用程式副本。This command creates a copy of the sample app on your computer.

    git clone https://github.com/Azure-Samples/azure-cosmos-db-graph-nodejs-getting-started.git
    
  4. 在 Visual Studio 中開啟解決方案檔案。Open the solution file in Visual Studio.

檢閱程式碼Review the code

此為選用步驟。This step is optional. 若您想要瞭解如何在程式碼中建立資料庫資源,則可檢閱下列程式碼片段。If you're interested in learning how the database resources are created in the code, you can review the following snippets. 或者也可以直接跳至更新您的連接字串Otherwise, you can skip ahead to Update your connection string.

下列程式碼片段全部取自 app.js 檔案。The following snippets are all taken from the app.js file.

  • 已建立 Gremlin 用戶端。The Gremlin client is created.

    const authenticator = new Gremlin.driver.auth.PlainTextSaslAuthenticator(
        `/dbs/${config.database}/colls/${config.collection}`, 
        config.primaryKey
    )
    
    
    const client = new Gremlin.driver.Client(
        config.endpoint, 
        { 
            authenticator,
            traversalsource : "g",
            rejectUnauthorized : true,
            mimeType : "application/vnd.gremlin-v2.0+json"
        }
    );
    
    

    這些設定都位於我們在下一節要編輯的 config.jsThe configurations are all in config.js, which we edit in the following section.

  • 定義了一系列的函式來執行不同的 Gremlin 作業。A series of functions are defined to execute different Gremlin operations. 這是其中一個:This is one of them:

    function addVertex1()
    {
        console.log('Running Add Vertex1'); 
        return client.submit("g.addV(label).property('id', id).property('firstName', firstName).property('age', age).property('userid', userid).property('pk', 'pk')", {
                label:"person",
                id:"thomas",
                firstName:"Thomas",
                age:44, userid: 1
            }).then(function (result) {
                    console.log("Result: %s\n", JSON.stringify(result));
            });
    }
    
  • 每個函式會搭配一個 Gremlin 查詢字串參數執行 client.execute 方法。Each function executes a client.execute method with a Gremlin query string parameter. 以下是執行 g.V().count() 的範例:Here is an example of how g.V().count() is executed:

    function countVertices()
    {
        console.log('Running Count');
        return client.submit("g.V().count()", { }).then(function (result) {
            console.log("Result: %s\n", JSON.stringify(result));
        });
    }
    
  • 在檔案結尾,接著會叫用所有方法。At the end of the file, all methods are then invoked. 這會一個接著一個執行所有方法:This will execute them one after the other:

    client.open()
    .then(dropGraph)
    .then(addVertex1)
    .then(addVertex2)
    .then(addEdge)
    .then(countVertices)
    .catch((err) => {
        console.error("Error running query...");
        console.error(err)
    }).then((res) => {
        client.close();
        finish();
    }).catch((err) => 
        console.error("Fatal error:", err)
    );
    

更新您的連接字串Update your connection string

  1. 更新 config.js 檔案。Open the config.js file.

  2. 在 config.js 中,替 config.endpoint 金鑰填入 Azure 入口網站的 [概觀] 頁面中的 [Gremlin URI] 值。In config.js, fill in the config.endpoint key with the Gremlin URI value from the Overview page of the Azure portal.

    config.endpoint = "https://<your_Gremlin_account_name>.gremlin.cosmosdb.azure.com:443/";

    在 Azure 入口網站的 [金鑰] 刀鋒視窗中檢視並複製存取金鑰

  3. 在 config.js 中,使用 Azure 入口網站 [索引鍵] 頁面中的 [主索引鍵] 值填入 config.primaryKey 值。In config.js, fill in the config.primaryKey value with the Primary Key value from the Keys page of the Azure portal.

    config.primaryKey = "PRIMARYKEY";

    Azure 入口網站 [索引鍵] 刀鋒視窗

  4. 針對 config.database 和 config.collection 的值,輸入資料庫名稱和圖形 (容器) 名稱。Enter the database name, and graph (container) name for the value of config.database and config.collection.

您完成的 config.js 檔案範例應如下所示︰Here's an example of what your completed config.js file should look like:

var config = {}

// Note that this must not have HTTPS or the port number
config.endpoint = "https://testgraphacct.gremlin.cosmosdb.azure.com:443/"; 
config.primaryKey = "Pams6e7LEUS7LJ2Qk0fjZf3eGo65JdMWHmyn65i52w8ozPX2oxY3iP0yu05t9v1WymAHNcMwPIqNAEv3XDFsEg==";
config.database = "graphdb"
config.collection = "Persons"

module.exports = config;

執行主控台應用程式Run the console app

  1. 開啟終端機視窗並變更 (透過 cd 命令) 至專案內含 package.json 檔案的安裝目錄。Open a terminal window and change (via cd command) to the installation directory for the package.json file that's included in the project.

  2. 執行 npm install 以安裝必要的 npm 模組,包括 gremlinRun npm install to install the required npm modules, including gremlin.

  3. 在終端機中執行 node app.js 來啟動您的節點應用程式。Run node app.js in a terminal to start your node application.

使用資料總管進行瀏覽Browse with Data Explorer

您現在可以回到 Azure 入口網站中的 [資料總管],檢視、查詢、修改並使用新的圖形資料。You can now go back to Data Explorer in the Azure portal to view, query, modify, and work with your new graph data.

在 [資料總管] 中,新的資料庫會出現在 [圖形] 窗格中。In Data Explorer, the new database appears in the Graphs pane. 展開資料庫,後面接著該容器,然後選取 [圖形] 。Expand the database, followed by the container, and then select Graph.

當您選取 [套用篩選條件] 時,範例應用程式所產生的資料會顯示在 [圖形] 索引標籤內的下一個窗格中。The data generated by the sample app is displayed in the next pane within the Graph tab when you select Apply Filter.

試著使用 .has('firstName', 'Thomas') 完成 g.V() 以測試篩選條件。Try completing g.V() with .has('firstName', 'Thomas') to test the filter. 請注意此值會區分大小寫。Note that the value is case sensitive.

在 Azure 入口網站中檢閱 SLAReview SLAs in the Azure portal

Azure 入口網站會監視您的 Cosmos DB 帳戶輸送量、儲存體、可用性、延遲和一致性。The Azure portal monitors your Cosmos DB account throughput, storage, availability, latency, and consistency. Azure Cosmos DB 服務等級協定 (SLA) 相關聯的計量圖表會顯示相較於實際效能的 SLA 值。Charts for metrics associated with an Azure Cosmos DB Service Level Agreement (SLA) show the SLA value compared to actual performance. 此計量套件可讓您以更透明的方式監視監視 SLA。This suite of metrics makes monitoring your SLAs transparent.

若要檢閱計量和 SLA:To review metrics and SLAs:

  1. 在您的 Cosmos DB 帳戶導覽功能表中,選取 [計量] 。Select Metrics in your Cosmos DB account's navigation menu.

  2. 選取一個索引標籤 (例如 [延遲] ),並在右側選取時間範圍。Select a tab such as Latency, and select a timeframe on the right. 比較圖表中的實際SLA 的資料行。Compare the Actual and SLA lines on the charts.

    Azure Cosmos DB 計量套件

  3. 檢閱其他索引標籤中的計量。Review the metrics on the other tabs.

清除資源Clean up your resources

完成您的 Web 應用程式和 Azure Cosmos DB 帳戶之後,您可以將建立的 Azure 資源刪除,以免產生更多費用。When you're done with your web app and Azure Cosmos DB account, you can delete the Azure resources you created so you don't incur more charges. 若要刪除資源:To delete the resources:

  1. 在 Azure 入口網站中,選取最左邊的 [資源群組] 。In the Azure portal, select Resource groups on the far left. 若已摺疊左側功能表,請選取展開按鈕加以展開。If the left menu is collapsed, select Expand button to expand it.

  2. 選取您在本快速入門中建立的資源群組。Select the resource group you created for this quickstart.

    Azure 入口網站中的計量

  3. 在新視窗中,選取 [刪除資源群組] 。In the new window, select Delete resource group.

    Azure 入口網站中的計量

  4. 在下個視窗中輸入要刪除的資源群組名稱,然後選取 [刪除] 。In the next window, enter the name of the resource group to delete, and then select Delete.

後續步驟Next steps

在本文章中,您已了解如何建立 Azure Cosmos DB 帳戶、如何使用 [資料總管] 來建立圖形,以及如何執行應用程式。In this article, you learned how to create an Azure Cosmos DB account, create a graph by using Data Explorer, and run an app. 您現在可以使用 Gremlin 來建置更複雜的查詢,以及實作強大的圖形周遊邏輯。You can now build more complex queries and implement powerful graph traversal logic by using Gremlin.