Configure an OSS mount

Step 1: Configure an OSS mount target

1. Log in to the Function Compute console. In the navigation pane on the left, choose Function Management > Functions.

2. In the top navigation bar, select a region. On the Functions page, click the name of the target function.

3. On the function details page, click the Configuration tab. Click Advanced Settings to the right of Modify. In the Advanced Settings panel, find the Storage section, turn on the switch for Mount OSS, configure the parameters, and then click Deploy.

   Parameter	Description	Example
   OSS Mount Target: Configure the OSS mount target.
   Bucket	Select an existing bucket. To create a new one, click Create OSS Bucket to open the OSS console. For information about fees associated with OSS, see OSS billing overview.	example-bucket
   Bucket Subdirectory	Specify a subdirectory in the bucket. This must be an absolute path. If you leave this empty or set it to /, the root directory of the bucket is mounted.	/files
   OSS Endpoint	When you select a bucket, the system automatically selects its endpoint. You can select Custom Endpoint to modify the endpoint address. For a list of OSS endpoints by region, see Regions and endpoints. Note If the bucket and your Function Compute function are in the same region, use an internal endpoint. If the bucket is in a different region, use a public endpoint. This incurs outbound data transfer fees.	Default Endpoint
   Local directory of a function	Specify a local directory in the function's runtime environment. The directory must be a subdirectory of /home, /mnt, or /data.	/mnt/oss
   Permissions on the local directory of the function	Select the permissions for the local directory. You can select Read-only or Read and Write.	Read/write

   Note

   The OSS mount feature depends on the function's network configuration. If your function is configured to access only a VPC and Allow Default NIC to Access Internet is set to No, the function must be able to access the internet through the specified VPC to use a public OSS endpoint. For details, see Configure a static public IP address.

Step 2: Access files in the mounted directory

After you configure the OSS mount target, you can access files in the mounted directory as if they were local.

1. On the function details page, click the Code tab. Write your code in the editor, and then click Deploy.

   The following code provides an example.

   import os
   
   
   def handler(event, context):
       # Mount directory
       mount_path = '/mnt/oss'
       
       # List files in the mount directory
       files = os.listdir(mount_path)
       print("Files in OSS mount:", files)  
       # Read a specific file from the mount directory
       file_path = os.path.join(mount_path, 'example.txt')
       if os.path.exists(file_path):
           with open(file_path, 'r') as file:
               content = file.read()
               print("Content of example.txt:", content)
       else:
           print("example.txt does not exist.")
       # Write a file to the mount directory
       write_path = os.path.join(mount_path, 'output.txt')
       with open(write_path, 'w') as file:
           file.write("Hello, OSS mount!")
           print("Wrote to output.txt in OSS mount.")
       
       return "Function execution completed."
     

   Note

   In the code, replace example.txt with the name of an actual file that exists in your mounted OSS directory.

2. After the code is deployed, click Code on the Test Function tab.

   After the execution is complete, you can view the results at the bottom of the Code tab. The Log Output tab shows the content of the example.txt file read from the OSS directory. You can also go to the OSS console to verify that the output.txt file was written to the corresponding mounted directory.

Check the storage class of your OSS bucket. If the storage class is Archive or Cold Archive, objects in the bucket are in a frozen state and must be restored before they can be accessed. Set the storage class of your OSS bucket to Standard.