Step 3. Create CreateThumbnailDemo Function and Test

Last updated: 2019-08-12 18:49:28


In this section, you will create a function to implement thumbnail program, and test the function through the console or by calling APIs.

Creating a CreateThumbnailDemo SCF

1) Log in to the Serverless Cloud Function Console. Select Guangzhou from the region list and click Create.

2) In Function configuration section, enter CreateThumbnailDemo as the function name, leave all other configuration options unchanged, and then click Next.

3) Go to the Function code section, and click Local upload zip file. Enter CreateThumbnail.main_handler as the execution method, select created in Step 2: Create Deployment Package, and click Next.

4) In the Triggering method section, you need to test the function manually, so no trigger method is added. Click Done.

Testing the CreateThumbnailDemo SCF

When a function is created, it is generally tested through the console or API, to ensure the function output meets the expectation, and then you can bind it to a trigger for practical application.

1) In the details page of the CreateThumbnailDemo function you just created, click Test.

2) Choose Upload File to COS/Delete File from COS Test Code from the drop-down list of test templates.

3) In the test code, set name to the name of bucket mybucket created in "Step 1: Prepare COS Bucket", and set key to the key value of /HappyFace.jpg uploaded in "Step 1: Prepare COS Bucket", as shown in the example below:

        "event": {
          "eventTime":"Unix timestamp",
            "requestSourceIP": "",
              "Authorization": "Uploaded authentication information"
            "cosNotificationId":"Configured or returned ID",
               "name":"mybucket", #set to demo bucket here
               "key":"/HappyFace.png", #set to demo file here
                 "Content-Type": "text/plain",
                 "x-cos-meta-test": "Custom meta",
                 "x-image-test": "Custom meta"
               "url": "Origin server URL for accessing files"

4) Click Run to view the results. This program is running normally if both upload and download are successful in the result。

5) Go to the COS Console, and click mybucketresized created in "Step 1: Prepare COS Bucket", to check whether a thumbnail named HappyFace.png is generated.

6) Download the picture and compare it with the size of original picture.