Spinnaker overview

Spinnaker different components port number table: link

Pipeline

I was very confused by the expression evaluation syntax used in UI in the beginning. Later on, I realized that it is just SpEL (Spring Expression Language). So an expression ${ a == 'xxx'} stands for a condition that tests whether the content of variable a equals the string xxx.

Then the question is how it looks up variable a and why not treat it as a literal? To answer this question, we need go deep into SpEL. This demo has a few examples. There are two ways to reference a variable:

1. Set it to the context and retrieve it by #var_name. This is called global variable.
2. Set the variable as a member of the root object, and evaluate the expression against the root object, then var_name is automatically evaluated to its value. In this case, # is not needed to prefix var_name.

Spinnaker chooses the second approach. It passes the stage context as the root object to the evaluation function, but the stage context is a Map, then how variables are resolved? It provides some customized property accessors to help SpEL resolve this property.

Another note about Evaluate Variables stage is that if we define multiple variables in this stage, then latter variable evaluation can use previous variables’ evaluation result. See code here that it puts the intermediate evaluation result back to the augmented context.

Let’s go deeper into SpEL (maybe I should open a new note for it). How is an expression evaluated? Most time we use TemplateParserContext so the expressions are enclosed inside a ${, $} pair. Expressions are first parsed and then evaluated. This getValue function is where the interesting story starts. This method is an abstract method in class CompiledExpression. But nobody inherits this class and nobody explicitly provides an implementation for it! All its implementations are indeeded constructed on the fly in SpelCompiler.

Does space matter? This is the another confusion I have with Spinnaker. In Spinnaker’s official documentations, it always adds spaces between the expression to be evaluated such as ${ xxxx }. Is this necessary. Actually not. SpEL trims the component. See code

Cloud driver

Cloud driver starts an docker registry agent, that pull image tags to cache (most likely Redis cache) every 30 seconds.

How to check the image tags in the docker registry?

Use an endpoint

ke spin-clouddriver-7dcfd6d5cb-xp9n2 -- bash -c 'curl localhost:7002/dockerRegistry/images/find?q=Build440' | jq .
[
  {
    "account": "my-ecr-registry",
    "artifact": {
      "metadata": {
        "labels": {},
        "registry": "242230929264.dkr.ecr.us-east-2.amazonaws.com"
      },
      "name": "evergreen-server",
      "reference": "242230929264.dkr.ecr.us-east-2.amazonaws.com/evergreen-server:Build440-2022_10_06-05_14_48-HEAD-db47ab910-Atif_Niyaz",
      "type": "docker",
      "version": "Build440-2022_10_06-05_14_48-HEAD-db47ab910-Atif_Niyaz"
    },
    "registry": "242230929264.dkr.ecr.us-east-2.amazonaws.com",
    "repository": "evergreen-server",
    "tag": "Build440-2022_10_06-05_14_48-HEAD-db47ab910-Atif_Niyaz"
  }
]

Just check the redis content

$ redis-cli -a password
127.0.0.1:6379> keys *taggedImage*my-ecr-registry*Build440*
1) "com.netflix.spinnaker.clouddriver.docker.registry.provider.DockerRegistryProvider:taggedImage:attributes:dockerRegistry:taggedImage:my-ecr-registry:evergreen-server:Build440-2022_10_06-05_14_48-HEAD-db47ab910-Atif_Niyaz"

common commands

curl -X GET http://localhost:8083/health
k exec spin-orca-6659fb9c74-rk9mz -- bash -c "curl -X PUT http://localhost:8083/admin/forceCancelExecution?executionId=01G7ARGX0ADTPPP6DZ8TNXTSBR"
k exec spin-orca-6659fb9c74-rk9mz -- bash -c "curl -X GET http://localhost:8083/v2/applications/server/pipelines"

ORCA

ExecutionRepository

It stores execution result. For RedisExecutionRepository, the keys are formatted as {executionType}:{id} Ex:

127.0.0.1:6379> keys pipeline*
...
9937) "pipeline:01G5JDXZW3WH2KMX4CAS9QTAQG"
9938) "pipeline:01FZ1JVC75XGB2VN9TPZRKX6RT:stageIndex"
9939) "pipeline:01G1VKET5AGN2MWQGWESYX20EF"
9940) "pipeline:01FVH18TPQ6M5E2EH5HZRQS5HN"

tips

1. When add podAnnotations, you should kill the halyard statefulset and services. 2.