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echo-server

This is copied from cloudposse/terraform-aws-components.

This component installs the Ealenn/Echo-Server to EKS clusters. The echo server is a server that sends it back to the client a JSON representation of all the data the server received, which is a combination of information sent by the client and information sent by the web server infrastructure. For further details, please consult the Echo-Server documentation.

Prerequisites

Echo server is intended to provide end-to-end testing of everything needed to deploy an application or service with a public HTTPS endpoint. It uses defaults where possible, such as using the default IngressClass, in order to verify that the defaults are sufficient for a typical application.

In order to minimize the impact of the echo server on the rest of the cluster, it does not set any configuration that would affect other ingresses, such as WAF rules, logging, or redirecting HTTP to HTTPS. Those settings should be configured in the IngressClass where possible.

Therefore, it requires several other components. At the moment, it supports 2 configurations:

  1. ALB with ACM Certificate
  • AWS Load Balancer Controller (ALB) version 2.2.0 or later, with ACM certificate auto-discovery enabled
  • A default IngressClass, which can be provisioned by the alb-controller component as part of deploying the controller, or can be provisioned separately, for example by the alb-controller-ingress-class component.
  • Pre-provisioned ACM TLS certificate covering the provisioned host name (typically a wildcard certificate covering all hosts in the domain)
  1. Nginx with Cert Manager Certificate
  • Nginx (via kubernetes/ingress-nginx controller). We recommend ingress-nginx v1.1.0 or later, but echo-server should work with any version that supports Ingress API version networking.k8s.io/v1.
  • jetstack/cert-manager configured to automatically (via Ingress Shim, installed by default) generate TLS certificates via a Cluster Issuer (by default, named letsEncrypt-prod).

In both configurations, it has these common requirements:

  • EKS component deployed, with component name specified in eks_component_name (defaults to "eks/cluster")
  • Kubernetes version 1.19 or later
  • Ingress API version networking.k8s.io/v1
  • kubernetes-sigs/external-dns
  • A default IngressClass, either explicitly provisioned or supported without provisioning by the Ingress controller.

Warnings

A Terraform plan may fail to apply, giving a Kubernetes authentication failure. This is due to a known issue with Terraform and the Kubernetes provider. During the "plan" phase Terraform gets a short-lived Kubernetes authentication token and caches it, and then tries to use it during "apply". If the token has expired by the time you try to run "apply", the "apply" will fail. The workaround is to run terraform apply -auto-approve without a "plan" file.

Usage

Stack Level: Regional

Use this in the catalog or use these variables to overwrite the catalog values.

Set ingress_type to "alb" if using alb-controller or "nginx" if using ingress-nginx.

Normally, you should not set the IngressClass or IngressGroup, as this component is intended to test the defaults. However, if you need to, set them in chart_values:

chart_values:
ingress:
class: "other-ingress-class"
alb:
# IngressGroup is specific to alb-controller
group_name: "other-ingress-group"

Note that if you follow recommendations and do not set the ingress class name, the deployed Ingress will have the ingressClassName setting injected by the Ingress controller, set to the then-current default. This means that if later you change the default IngressClass, the Ingress will be NOT be updated to use the new default. Furthermore, because of limitations in the Helm provider, this will not be detected as drift. You will need to destroy and re-deploy the echo server to update the Ingress to the new default.

components:
terraform:
echo-server:
settings:
spacelift:
workspace_enabled: true
vars:
enabled: true
name: "echo-server"
kubernetes_namespace: "echo"
description: "Echo server, for testing purposes"
create_namespace: true
timeout: 180
wait: true
atomic: true
cleanup_on_fail: true

ingress_type: "alb" # or "nginx"
# %[1]v is the tenant name, %[2]v is the stage name, %[3]v is the region name
hostname_template: "echo.%[3]v.%[2]v.%[1]v.sample-domain.net"

In rare cases where some ingress controllers do not support the ingressClassName field, you can restore the old kubernetes.io/ingress.class annotation by setting ingress.use_ingress_class_annotation: true in chart_values.

Variables

Required Variables

hostname_template (string) required

The format() string to use to generate the hostname via format(var.hostname_template, var.tenant, var.stage, var.environment)"
Typically something like "echo.%[3]v.%[2]v.example.com".


kubernetes_namespace (string) required

The namespace to install the release into.

region (string) required

AWS Region

Optional Variables

atomic (bool) optional

If set, installation process purges chart on fail. The wait flag will be set automatically if atomic is used.


Default value: true

chart_values (any) optional

Addition map values to yamlencode as helm_release values.


Default value: { }

chart_version (string) optional

Specify the exact chart version to install. If this is not specified, the latest version is installed.


Default value: null

cleanup_on_fail (bool) optional

Allow deletion of new resources created in this upgrade when upgrade fails.


Default value: true

create_namespace (bool) optional

Create the Kubernetes namespace if it does not yet exist


Default value: true

description (string) optional

Set release description attribute (visible in the history).


Default value: null

eks_component_name (string) optional

The name of the eks component


Default value: "eks/cluster"

helm_manifest_experiment_enabled (bool) optional

Enable storing of the rendered manifest for helm_release so the full diff of what is changing can been seen in the plan


Default value: false

ingress_type (string) optional

Set to 'nginx' to create an ingress resource relying on an NGiNX backend for the echo-server service. Set to 'alb' to create an ingress resource relying on an AWS ALB backend for the echo-server service. Leave blank to not create any ingress for the echo-server service.


Default value: null

kube_data_auth_enabled (bool) optional

If true, use an aws_eks_cluster_auth data source to authenticate to the EKS cluster.
Disabled by kubeconfig_file_enabled or kube_exec_auth_enabled.



Default value: false

kube_exec_auth_aws_profile (string) optional

The AWS config profile for aws eks get-token to use


Default value: ""

kube_exec_auth_aws_profile_enabled (bool) optional

If true, pass kube_exec_auth_aws_profile as the profile to aws eks get-token


Default value: false

kube_exec_auth_enabled (bool) optional

If true, use the Kubernetes provider exec feature to execute aws eks get-token to authenticate to the EKS cluster.
Disabled by kubeconfig_file_enabled, overrides kube_data_auth_enabled.



Default value: true

kube_exec_auth_role_arn (string) optional

The role ARN for aws eks get-token to use


Default value: ""

kube_exec_auth_role_arn_enabled (bool) optional

If true, pass kube_exec_auth_role_arn as the role ARN to aws eks get-token


Default value: true

kubeconfig_context (string) optional

Context to choose from the Kubernetes config file.
If supplied, kubeconfig_context_format will be ignored.



Default value: ""

kubeconfig_context_format (string) optional

A format string to use for creating the kubectl context name when
kubeconfig_file_enabled is true and kubeconfig_context is not supplied.
Must include a single %s which will be replaced with the cluster name.



Default value: ""

kubeconfig_exec_auth_api_version (string) optional

The Kubernetes API version of the credentials returned by the exec auth plugin


Default value: "client.authentication.k8s.io/v1beta1"

kubeconfig_file (string) optional

The Kubernetes provider config_path setting to use when kubeconfig_file_enabled is true


Default value: ""

kubeconfig_file_enabled (bool) optional

If true, configure the Kubernetes provider with kubeconfig_file and use that kubeconfig file for authenticating to the EKS cluster


Default value: false

repository (string) optional

Repository URL where to locate the requested chart.


Default value: null

timeout (number) optional

Time in seconds to wait for any individual kubernetes operation (like Jobs for hooks). Defaults to 300 seconds


Default value: null

verify (bool) optional

Verify the package before installing it. Helm uses a provenance file to verify the integrity of the chart; this must be hosted alongside the chart


Default value: false

wait (bool) optional

Will wait until all resources are in a ready state before marking the release as successful. It will wait for as long as timeout. Defaults to true.


Default value: true

Context Variables

The following variables are defined in the context.tf file of this module and part of the terraform-null-label pattern.

additional_tag_map (map(string)) optional

Additional key-value pairs to add to each map in tags_as_list_of_maps. Not added to tags or id.
This is for some rare cases where resources want additional configuration of tags
and therefore take a list of maps with tag key, value, and additional configuration.


Required: No

Default value: { }

attributes (list(string)) optional

ID element. Additional attributes (e.g. workers or cluster) to add to id,
in the order they appear in the list. New attributes are appended to the
end of the list. The elements of the list are joined by the delimiter
and treated as a single ID element.


Required: No

Default value: [ ]

context (any) optional

Single object for setting entire context at once.
See description of individual variables for details.
Leave string and numeric variables as null to use default value.
Individual variable settings (non-null) override settings in context object,
except for attributes, tags, and additional_tag_map, which are merged.


Required: No

Default value:

{
"additional_tag_map": {},
"attributes": [],
"delimiter": null,
"descriptor_formats": {},
"enabled": true,
"environment": null,
"id_length_limit": null,
"label_key_case": null,
"label_order": [],
"label_value_case": null,
"labels_as_tags": [
"unset"
],
"name": null,
"namespace": null,
"regex_replace_chars": null,
"stage": null,
"tags": {},
"tenant": null
}
delimiter (string) optional

Delimiter to be used between ID elements.
Defaults to - (hyphen). Set to "" to use no delimiter at all.


Required: No

Default value: null

descriptor_formats (any) optional

Describe additional descriptors to be output in the descriptors output map.
Map of maps. Keys are names of descriptors. Values are maps of the form
\{<br/> format = string<br/> labels = list(string)<br/> \}
(Type is any so the map values can later be enhanced to provide additional options.)
format is a Terraform format string to be passed to the format() function.
labels is a list of labels, in order, to pass to format() function.
Label values will be normalized before being passed to format() so they will be
identical to how they appear in id.
Default is {} (descriptors output will be empty).


Required: No

Default value: { }

enabled (bool) optional

Set to false to prevent the module from creating any resources
Required: No

Default value: null

environment (string) optional

ID element. Usually used for region e.g. 'uw2', 'us-west-2', OR role 'prod', 'staging', 'dev', 'UAT'
Required: No

Default value: null

id_length_limit (number) optional

Limit id to this many characters (minimum 6).
Set to 0 for unlimited length.
Set to null for keep the existing setting, which defaults to 0.
Does not affect id_full.


Required: No

Default value: null

label_key_case (string) optional

Controls the letter case of the tags keys (label names) for tags generated by this module.
Does not affect keys of tags passed in via the tags input.
Possible values: lower, title, upper.
Default value: title.


Required: No

Default value: null

label_order (list(string)) optional

The order in which the labels (ID elements) appear in the id.
Defaults to ["namespace", "environment", "stage", "name", "attributes"].
You can omit any of the 6 labels ("tenant" is the 6th), but at least one must be present.


Required: No

Default value: null

label_value_case (string) optional

Controls the letter case of ID elements (labels) as included in id,
set as tag values, and output by this module individually.
Does not affect values of tags passed in via the tags input.
Possible values: lower, title, upper and none (no transformation).
Set this to title and set delimiter to "" to yield Pascal Case IDs.
Default value: lower.


Required: No

Default value: null

labels_as_tags (set(string)) optional

Set of labels (ID elements) to include as tags in the tags output.
Default is to include all labels.
Tags with empty values will not be included in the tags output.
Set to [] to suppress all generated tags.
Notes:
The value of the name tag, if included, will be the id, not the name.
Unlike other null-label inputs, the initial setting of labels_as_tags cannot be
changed in later chained modules. Attempts to change it will be silently ignored.


Required: No

Default value:

[
"default"
]
name (string) optional

ID element. Usually the component or solution name, e.g. 'app' or 'jenkins'.
This is the only ID element not also included as a tag.
The "name" tag is set to the full id string. There is no tag with the value of the name input.


Required: No

Default value: null

namespace (string) optional

ID element. Usually an abbreviation of your organization name, e.g. 'eg' or 'cp', to help ensure generated IDs are globally unique
Required: No

Default value: null

regex_replace_chars (string) optional

Terraform regular expression (regex) string.
Characters matching the regex will be removed from the ID elements.
If not set, "/[^a-zA-Z0-9-]/" is used to remove all characters other than hyphens, letters and digits.


Required: No

Default value: null

stage (string) optional

ID element. Usually used to indicate role, e.g. 'prod', 'staging', 'source', 'build', 'test', 'deploy', 'release'
Required: No

Default value: null

tags (map(string)) optional

Additional tags (e.g. {'BusinessUnit': 'XYZ'}).
Neither the tag keys nor the tag values will be modified by this module.


Required: No

Default value: { }

tenant (string) optional

ID element (Rarely used, not included by default). A customer identifier, indicating who this instance of a resource is for
Required: No

Default value: null

Outputs

hostname

Hostname of the deployed echo server

metadata

Block status of the deployed release

Dependencies

Requirements

  • terraform, version: >= 1.0.0
  • aws, version: >= 4.0
  • helm, version: >= 2.0
  • kubernetes, version: >= 2.7.1, != 2.21.0

Providers

  • aws, version: >= 4.0

Modules

NameVersionSourceDescription
echo_server0.10.1cloudposse/helm-release/awsn/a
eks1.5.0cloudposse/stack-config/yaml//modules/remote-staten/a
iam_roleslatest../../account-map/modules/iam-rolesn/a
this0.25.0cloudposse/label/nulln/a

Resources

The following resources are used by this module:

Data Sources

The following data sources are used by this module:

References

Changelog

Changes in PR #893, components version ~v1.337.0

  • Moved eks/echo-server v1.147.0 to /deprecated/eks/echo-server for those who still need it and do not want to switch. It may later become the basis for an example app or something similar.
  • Removed dependency on and connection to the eks/alb-controller-ingress-group component
  • Added liveness probe, and disabled logging of probe requests. Probe request logging can be restored by setting livenessProbeLogging: true in chart_values
  • This component no longer configures automatic redirects from HTTP to HTTPS. This is because for ALB controller, setting that on one ingress sets it for all ingresses in the same IngressGroup, and it is a design goal that deploying this component does not affect other Ingresses (with the obvious exception of possibly being the first to create the Application Load Balancer).
  • Removed from chart_values:ingress.nginx.class (was set to "nginx") and ingress.alb.class (was set to "alb"). IngressClass should usually not be set, as this component is intended to be used to test the defaults, including the default IngressClass. However, if you do want to set it, you can do so by setting ingress.class in chart_values.
  • Removed the deprecated kubernetes.io/ingress.class annotation by default. It can be restored by setting ingress.use_ingress_class_annotation: true in chart_values. IngressClass is now set using the preferred ingressClassName field of the Ingress resource.