Access an ApsaraDB for MongoDB database

Before you start

• Create an ApsaraDB for MongoDB database instance.

  • Create an ApsaraDB for MongoDB standalone instance

  • Create a replica set instance

  • Create a sharded cluster instance

    In this topic, a sharded cluster instance is used as an example.

  Important

  • Make sure that the database instance that you create is in the same region as the function that needs to access the database instance.

  • We recommend that you create the database instance in a zone that Function Compute supports. For more information, see Zones where Function Compute is available.

    If your database instance is not in a zone that is supported by Function Compute, you can create a vSwitch in your VPC in the same zone as Function Compute and use this vSwitch ID in the VPC configurations of the function. vSwitches in the same VPC can communicate with each other over the private network. Therefore, Function Compute can use the vSwitch to access resources in VPCs that reside in other zones. For more information, see What do I do if the vSwitch is in unsupported zone error is reported?

• Create a database named test-db and a database collection named fc_col. For more information, see Create a database and a collection and write data.

  In this topic, the code logic in the sample code of index.py is to insert a piece of document data into the fc-col collection of the test-db database.

Procedure

1. Install Serverless Devs and Docker and configure the AccessKey information.

   For more information, see Install Serverless Devs and dependencies and Configure Serverless Devs.

2. Run the following command to initialize a project.

   sudo s init

   In the CLI, specify Alibaba Cloud as the vendor, specify the quick start mode, and select a built-in Python runtime. Configure the project name and the region where the project is deployed. In this example, the start-fc-mongodb-python project is deployed in the China (Hangzhou) region.

3. Run the following command to go to the project directory.

   cd start-fc-mongodb-python

4. Modify the directory file based on your own business requirements.

   • Edit the s.yaml file. Example:

     edition: 3.0.0
     name: hello-world-app
     access: "default"
     
     vars: # The global variables.
       region: "cn-hangzhou"
     
     resources:
       hello_world:
         component: fc3 # The component name.
         # actions:       # The custom execution logic. For more information about actions, visit https://docs.serverless-devs.com/serverless-devs/yaml#%E8%A1%8C%E4%B8%BA%E6%8F%8F%E8%BF%B0actions.
         props:
           region: ${vars.region}              # For information about how to use variables, visit https://docs.serverless-devs.com/serverless-devs/yaml#%E5%8F%98%E9%87%8F%E8%B5%8B%E5%80%BC.
           functionName: "start-python-xbk4"
           description: 'hello world by serverless devs'
           runtime: "python3.9"
           code: ./code
           handler: index.handler
           memorySize: 128
           timeout: 30
           internetAccess: true
           vpcConfig:
            vpcId: vpc-bp11y195luy47h8cm**** # The ID of the VPC in which the database instance resides.
            securityGroupId: sg-bp1el3hto8hhkdup**** # The ID of the security group.
            vSwitchIds: 
             - vsw-bp18vwna9x79koh3q**** # Make sure that the CIDR block of the vSwitch is added to the whitelist of the database instance. 
           environmentVariables:      
            MONGO_DATABASE: test-db # The name of the database.
            MONGO_URL: mongodb://username:password@d-bp1b05cac9df0dd****.mongodb.rds.aliyuncs.com:37**  # The endpoint of the database. In the code, username and password indicate the username and password of the account that is used to connect to the database. If the username and password contain special characters, you must escape them in accordance with RFC 3986.
            

     Important

     Make sure that the CIDR block of the vSwitch that you configure for the function is added to the whitelist of the database instance. For more information, see Configure an IP address whitelist for the database.

   • Edit the index.py file. The following code provides an example. The code logic is to insert a piece of document data into the fc-col collection of the test-db database.

     # -*- coding: utf-8 -*-
     import os
     from pymongo import MongoClient   # You need to install the pymongo library first.
     
     
     def handler(event, context):
         dbName = os.environ['MONGO_DATABASE']
         url = os.environ['MONGO_URL']
     
         client = MongoClient(url)
     
         col = client[dbName]['fc_col']
         col.insert_one(dict(DEMO="FC", MSG="Hello FunctionCompute For MongoDB"))
         doc = col.find_one(dict(DEMO="FC"))
         print('find documents:' + str(doc))
         return str(doc)

5. Run the following command to build a project.

   sudo s build --use-docker

6. Run the following command to deploy the project.

   sudo s deploy -y

7. Run the following command to invoke the function.

   sudo s invoke -e "{}"

   The following code snippet shows the expected output. The returned result indicates that a data record has been successfully inserted into the ApsaraDB for MongoDB database.

   ========= FC invoke Logs begin =========
   FC Invoke Start RequestId: 1-65d30578-1586adb3-4d0f099c1ada
   find documents:{'_id': ObjectId('65d2faef467c916ed6401a73'), 'DEMO': 'FC', 'MSG': 'Hello FunctionCompute For MongoDB'}
   FC Invoke End RequestId: 1-65d30578-1586adb3-4d0f099c1ada
   
   Duration: 161.75 ms, Billed Duration: 162 ms, Memory Size: 256 MB, Max Memory Used: 34.44 MB
   ========= FC invoke Logs end =========
   
   FC Invoke instanceId: c-65d304d7-15f440b6-20443f00e921
   
   FC Invoke Result:
   {'_id': ObjectId('65d2faef467c916ed6401a73'), 'DEMO': 'FC', 'MSG': 'Hello FunctionCompute For MongoDB'}
   
   
   End of method: invoke

Configure an IP address whitelist for the database

A sharded cluster instance is used as an example.

1. Log on to the ApsaraDB for MongoDB console.

2. In the top navigation bar, select a region.

3. In the left-side navigation pane, click Sharded Cluster Instances.

4. On the Sharded Cluster Instances page, click the name of the desired cluster.

5. In the left-side navigation pane, choose Data Security > Whitelist Settings.

6. On the Whitelist Settings page, find the desired whitelist group, click the icon in the Actions column. In the drop-down menu, choose Manually Modify.

7. In the Manually Modify panel, enter an IP address and click OK.

   Important

   You must specify an IP address that belongs to the CIDR block of the vSwitch that you add when you configure the network for Function Compute.

More information

• For more information about the sample code for accessing an ApsaraDB for MongoDB database, see Python access mongodb database in Function Compute.

• For more information about how to view the information about the configured vSwiches in Function Compute and add CIDR blocks of Function Compute vSwiches to the whitelist of an ApsaraDB RDS for MongoDB database, see Configure network settings and Configure an IP address whitelist.

• You can troubleshoot a database connection failure by referring to How to troubleshoot database access failures?