Chapter 13. Configuring functions

Procedure

1. Run the following command in the function project directory:

   $ kn func config

   You can also specify the function project directory by using the --path or -p option.

2. Use the interactive interface to perform the necessary operation. For example, using the utility to list configured volumes produces an output similar to this:

   $ kn func config
   ? What do you want to configure? Volumes
   ? What operation do you want to perform? List
   Configured Volumes mounts:
   - Secret "mysecret" mounted at path: "/workspace/secret"
   - Secret "mysecret2" mounted at path: "/workspace/secret2"

   This scheme shows all operations available in the interactive utility and how to go to them:

   kn func config
      ├─> Environment variables
      │               ├─> Add
      │               │    ├─> ConfigMap: Add all key-value pairs from a config map
      │               │    ├─> ConfigMap: Add value from a key in a config map
      │               │    ├─> Secret: Add all key-value pairs from a secret
      │               │    └─> Secret: Add value from a key in a secret
      │               ├─> List: List all configured environment variables
      │               └─> Remove: Remove a configured environment variable
      └─> Volumes
              ├─> Add
              │    ├─> ConfigMap: Mount a config map as a volume
              │    └─> Secret: Mount a secret as a volume
              ├─> List: List all configured volumes
              └─> Remove: Remove a configured volume

3. Optional: Deploy the function to make the changes take effect:

   $ kn func deploy -p test

Procedure

1. Open the func.yaml file for your function.

2. For every annotation that you want to add, add the following YAML to the annotations section:

   name: test
   namespace: ""
   runtime: go
   ...
   annotations:
     <annotation_name>: "<annotation_value>" 

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   1

   Substitute <annotation_name>: "<annotation_value>" with your annotation.

   For example, to indicate that Alice authored the function, include the following annotation:

   name: test
   namespace: ""
   runtime: go
   ...
   annotations:
     author: "alice@example.com"

3. Save the configuration.

Procedure

1. Open the func.yaml file for your function.

2. For each secret you want to mount as a volume, add the following YAML to the volumes section:

   name: test
   namespace: ""
   runtime: go
   ...
   volumes:
   - secret: mysecret
     path: /workspace/secret

   • Substitute mysecret with the name of the target secret.

   • Substitute /workspace/secret with the path where you want to mount the secret.

     For example, to mount the addresses secret, use the following YAML:

     name: test
     namespace: ""
     runtime: go
     ...
     volumes:
     - configMap: addresses
       path: /workspace/secret-addresses

3. Save the configuration.

Procedure

1. Open the func.yaml file for your function.

2. For each config map you want to mount as a volume, add the following YAML to the volumes section:

   name: test
   namespace: ""
   runtime: go
   ...
   volumes:
   - configMap: myconfigmap
     path: /workspace/configmap

   • Substitute myconfigmap with the name of the target config map.

   • Substitute /workspace/configmap with the path where you want to mount the config map.

     For example, to mount the addresses config map, use the following YAML:

     name: test
     namespace: ""
     runtime: go
     ...
     volumes:
     - configMap: addresses
       path: /workspace/configmap-addresses

3. Save the configuration.

Procedure

1. Open the func.yaml file for your function.

2. For each value from a secret key-value pair that you want to assign to an environment variable, add the following YAML to the envs section:

   name: test
   namespace: ""
   runtime: go
   ...
   envs:
   - name: EXAMPLE
     value: '{{ secret:mysecret:key }}'

   • Substitute EXAMPLE with the name of the environment variable.
   • Substitute mysecret with the name of the target secret.

   • Substitute key with the key mapped to the target value.

     For example, to access the user ID that is stored in userdetailssecret, use the following YAML:

     name: test
     namespace: ""
     runtime: go
     ...
     envs:
     - value: '{{ configMap:userdetailssecret:userid }}'

3. Save the configuration.

Procedure

1. Open the func.yaml file for your function.

2. For each value from a config map key-value pair that you want to assign to an environment variable, add the following YAML to the envs section:

   name: test
   namespace: ""
   runtime: go
   ...
   envs:
   - name: EXAMPLE
     value: '{{ configMap:myconfigmap:key }}'

   • Substitute EXAMPLE with the name of the environment variable.
   • Substitute myconfigmap with the name of the target config map.

   • Substitute key with the key mapped to the target value.

     For example, to access the user ID that is stored in userdetailsmap, use the following YAML:

     name: test
     namespace: ""
     runtime: go
     ...
     envs:
     - value: '{{ configMap:userdetailsmap:userid }}'

3. Save the configuration.

Procedure

1. Open the func.yaml file for your function.

2. For every secret for which you want to import all key-value pairs as environment variables, add the following YAML to the envs section:

   name: test
   namespace: ""
   runtime: go
   ...
   envs:
   - value: '{{ secret:mysecret }}' 

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   Substitute mysecret with the name of the target secret.

   For example, to access all user data that is stored in userdetailssecret, use the following YAML:

   name: test
   namespace: ""
   runtime: go
   ...
   envs:
   - value: '{{ configMap:userdetailssecret }}'

3. Save the configuration.

Procedure

1. Open the func.yaml file for your function.

2. For every config map for which you want to import all key-value pairs as environment variables, add the following YAML to the envs section:

   name: test
   namespace: ""
   runtime: go
   ...
   envs:
   - value: '{{ configMap:myconfigmap }}'

   Substitute myconfigmap with the name of the target config map.

   For example, to access all user data that is stored in userdetailsmap, use the following YAML:

   name: test
   namespace: ""
   runtime: go
   ...
   envs:
   - value: '{{ configMap:userdetailsmap }}'

3. Save the file.