Common structs for Helm

[alpeb]

This PR adds pkg/inject/template-values.go which contains the structs
needed to set the helm variables during injection. They can also be
leveraged during installation:

package inject

type (
        // Image contains the details to define a container image
        Image struct {
                Name       string
                PullPolicy string
                Version    string
        }

        // Port contains all the port-related setups
        Port struct {
                Admin               int32
                Control             int32
                Inbound             int32
                Outbound            int32
                IgnoreInboundPorts  string
                IgnoreOutboundPorts string
        }

        // Constraints wraps the Limit and Request settings for computational resources
        Constraints struct {
                Limit   string
                Request string
        }

        // Resources represents the computational resources setup for a given container
        Resources struct {
                CPU    Constraints
                Memory Constraints
        }

        // Identity contains the fields to set the identity variables in the proxy
        // sidecar container
        Identity struct {
                TrustDomain  string
                TrustAnchors string
        }

        // Proxy contains the fields to set the proxy sidecar container
        Proxy struct {
                Component             string
                ClusterDomain         string
                DisableIdentity       bool
                EnableExternalProfile bool
                HighAvailability      bool
                Identity              *Identity
                Image                 Image
                LogLevel              string
                ControlPlaneNamespace string
                Port                  Port
                UID                   int64
                ResourceRequirements  *Resources
        }

        // ProxyInit contains the fields to set the proxy-init container
        ProxyInit struct {
                Image                Image
                Port                 Port
                UID                  int64
                ResourceRequirements *Resources
        }
)

Signed-off-by: Alejandro Pedraza alejandro@buoyant.io

[l5d-bot]

Integration test results for 241c4d3: success 🎉
Log output: https://gist.github.com/68bd7539b2d6abb2474c097899ca951a

[ihcsim]

Thanks for putting this together. Per slack convo, I removed some of the redundant nested variables from values.yaml, which relied on YAML anchors to inherit their values from top-level variables. This approach is error-prone because e.g. helm install --set HighAvailability=true will only override the values of {{.HighAvailability}}, but not {{.Proxy.HighAvailability}}.

Here's the list of structs that correspond to the YAML in my values.yaml:

// top level variables 
type InjectValues struct {
	Namespace        string
	ClusterDomain    string
	HighAvailability bool

	Proxy     *Proxy
	ProxyInit *ProxyInit
}

type Proxy struct {
	Capabilities          *Capabilities
	Component             string
	DisableIdentity       bool
	DisableTap            bool
	EnableExternalProfile bool
	Image                 *Image
	Identity              *Identity
	LogLevel              string
	MountPaths            []*MountPath
	Ports                 *Ports
	Resources             *Resources
	UID                   string
}

type ProxyInit struct {
	Capabilities        *Capabilities
	IgnoreInboundPorts  string
	IgnoreOutboundPorts string
	Image               *Image
	MountPaths          []*MountPath
	Resources           *Resources
}

type Capabilities struct {
	Add  []string
	Drop []string
}

type Image struct {
	Name       string
	Version    string
	PullPolicy string
}

type Identity struct {
	Issuer struct {
		CrtPEM string
	}

	TrustDomain string
}

type MountPath struct {
	Name      string
	MountPath string
}

type Resources struct {
	CPU    Constraints
	Memory Constraints
}

type Constraints struct {
	Limit   string
	Request string
}

type Ports struct {
	Admin    int
	Control  int
	Inbound  int
	Outbound int
}

LMK if this works.

[alpeb]

Looks great @ihcsim 👍
I've pushed a change with your modifications, plus some of my own:

• I moved Identity from Proxy to InjectValues, according to values.yaml
• In both Proxy and ProxyInit I replaced MountPaths []*MountPath with SAMountPath *SAMountPath given we're only adding a mount for the ServiceAccount so no need of a slice here
• I created a separate Issuer struct to be able to instantiate that piece

[l5d-bot]

Integration test results for 273eef1: fail 😕
Log output: https://gist.github.com/090f0df58068a8454fd1c2fc62be6484

[siggy]

lgtm just a couple questions 🚢 👍

[siggy]

can/should this be an array?

[alpeb]

yeah we might. WDYT @ihcsim ?

[ihcsim]

The value of this variable eventually gets mapped into the args of the proxy-init container. From a rendering perspective, I think it should remain as string. Otherwise, won't we end up with something like:

  initContainers:
  - args:
    ...
    - --inbound-ports-to-ignore
    - [4190,4191]
    - --outbound-ports-to-ignore
    - ["443"] 

[ihcsim]

I made a mistake in the Identity struct. Instead of Identity.Issuer.CrtPEM, the data plane should be using Identity.TrustAnchorsPEM. Although they both have the same default values, the former is used on the identity service (via Secret), whereas the trust anchor is used in the proxy's LINKERD2_PROXY_IDENTITY_TRUST_ANCHORS env var, which I believe is the one needed here.

[alpeb]

I've just pushed the changes according to the previous message. I've also changed the name of injectValues to Values, to avoid stuttering since we're already in the inject package.
@ihcsim please let me know when you're ready for me to merge this into isim/helm-charts ⭐

[l5d-bot]

Integration test results for 241bb7f: success 🎉
Log output: https://gist.github.com/faa8b9386df6519592d08603ec48650d