Version:

Create a Git Function

This tutorial shows how you can build a Function from code and dependencies stored in a Git repository, which is an alternative way to keeping the code in the Function CR. The tutorial is based on the Function from the orders service example. It describes steps required to fetch the Function's source code and dependencies from a public Git repository that does not need any authentication method. However, it also provides additional guidance on how to secure it if you are using a private repository.

NOTE: To learn more about Git repository sources for Functions and different ways of securing your repository, read about the Git source type.

NOTE: Read about Istio sidecars in Kyma and why you want them. Then, check how to enable automatic Istio sidecar proxy injection. For more details, see Default Istio setup in Kyma.

Steps

Follow these steps:

kubectl
Kyma Dashboard

Export these variables:

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export GIT_FUNCTION={GIT_FUNCTION_NAME}
export NAMESPACE={FUNCTION_NAMESPACE}

Create a Secret (optional).

If you use a secured repository, you must first create a Secret for one of these authentication methods:

Basic authentication (username and password or token) to this repository in the same Namespace as the Function:

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cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Secret
metadata:
  name: git-creds-basic
  namespace: $NAMESPACE
type: Opaque
data:
  username: {BASE64_ENCODED_USERNAME}
  password: {BASE64_ENCODED_PASSWORD_OR_TOKEN}
EOF

SSH key:

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cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Secret
metadata:
  name: git-creds-key
  namespace: $NAMESPACE
type: Opaque
data:
  key: {BASE64_ENCODED_PRIVATE_SSH_KEY}
EOF

NOTE: Read more about the supported authentication methods.

Create a GitRepository CR that specifies the Git repository metadata:
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```
cat <<EOF | kubectl apply -f -
apiVersion: serverless.kyma-project.io/v1alpha1
kind: GitRepository
metadata:
  name: $GIT_FUNCTION
  namespace: $NAMESPACE
spec:
  url: "https://github.com/kyma-project/examples.git"
EOF
```
NOTE: If you use a secured repository, add the auth object with the adequate type and secretName fields to the spec:
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```
spec:
  ...
  auth:
    type: # "basic" or "key"
    secretName: # "git-creds-basic" or "git-creds-key"
```
NOTE: To avoid performance degradation caused by large Git repositories and large monorepos, Function Controller implements a configurable backoff period for the source checkout based on APP_FUNCTION_REQUEUE_DURATION. This behavior can be disabled, allowing the controller to perform the source checkout with every reconciliation loop by marking the Function CR with the annotation serverless.kyma-project.io/continuousGitCheckout: true

Create a Function CR that specifies the Function's logic and points to the directory with code and dependencies in the given repository.

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cat <<EOF | kubectl apply -f -
apiVersion: serverless.kyma-project.io/v1alpha1
kind: Function
metadata:
  name: $GIT_FUNCTION
  namespace: $NAMESPACE
spec:
  type: git
  runtime: nodejs14
  source: $GIT_FUNCTION
  reference: main
  baseDir: orders-service/function
EOF

NOTE: See this Function's code and dependencies.

Check if your Function was created and all conditions are set to True:

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kubectl get functions $GIT_FUNCTION -n $NAMESPACE

You should get a result similar to this example:

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NAME            CONFIGURED   BUILT     RUNNING   RUNTIME    VERSION   AGE
test-function   True         True      True      nodejs14   1         96s