nic-add-policy
DevelopmentStep-by-step checklist for adding a new Policy CRD type to NIC. Use when implementing a new policy like AccessControl, RateLimit, JWTAuth, ExternalAuth, BasicAuth, IngressMTLS, EgressMTLS, OIDC, WAF, APIKey, Cache, or CORS, or extending the policy system with a new policy type.
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Adding a New Policy Type
Follow these steps IN ORDER. Each step depends on the previous.
Step 1: Define the CRD type
File: pkg/apis/configuration/v1/types.go
- Add a new struct (e.g.,
type MyPolicy struct { ... }) - Add a
*MyPolicypointer field toPolicySpec - Use kubebuilder markers for validation
- JSON tags: kebab-case for NGINX-proxy fields, camelCase for K8s fields
*bool/*int= optional/nullable. Plainbool/int= required or zero-default- Booleans defaulting to
falsemust be non-pointer value types
Step 2: Regenerate deep copy
Run make update-codegen to update zz_generated.deepcopy.go.
Step 3: Regenerate CRDs
Run make update-crds to regenerate config/crd/bases/, deploy/crds.yaml, and chart CRDs.
Step 4: Add validation
File: pkg/apis/configuration/validation/policy.go
- Add
validate<MyPolicy>(spec *v1.MyPolicy, fieldPath *field.Path) field.ErrorList - Wire into
validatePolicySpec()with field count increment and feature gate check - Add tests in
policy_test.gowith valid and invalid cases
Step 5: Add template structs
File: internal/configs/version2/http.go
- Add struct (e.g.,
type MyPolicyConfig struct { ... }) - Add
*MyPolicyConfigor fields toServer,Location, or both - If the policy needs HTTP-level directives (zones, maps), add fields to
VirtualServerConfig
Step 6: Add config generation
File: internal/configs/policy.go
- Add field(s) to
policiesCfg - Add
add<MyPolicy>Config()method following the pattern below - Wire into the
switchingeneratePolicies() - Add tests in
policy_test.go
Step 7: Wire into VirtualServer generation
File: internal/configs/virtualserver.go
- In
GenerateVirtualServerConfig(), extract frompoliciesCfgand assign toversion2fields - Use
addPoliciesCfgToLocation()for location-level assignment
Step 8: Wire into Ingress generation (if applicable)
File: internal/configs/ingress.go
- In
generateNginxCfg(), extract frompoliciesCfgand assign toversion1fields - Handle mergeable ingress in
generateNginxCfgForMergeableIngresses()
Step 9: Add NGINX template directives
- Version 2:
internal/configs/version2/nginx.virtualserver.tmplandinternal/configs/version2/nginx-plus.virtualserver.tmpl - Version 1:
internal/configs/version1/nginx.ingress.tmplandinternal/configs/version1/nginx-plus.ingress.tmpl - Use
{{- if }}/{{- with }}guards around directive blocks - Template helpers go in
internal/configs/version2/template_helper.goand/orinternal/configs/version1/template_helper.go, matching the template version you are updating - HTTP-level directives (zones, maps) go BEFORE
server{} - Server-level inside
server{}, location-level inside eachlocation{}
Step 10: Update snapshot tests
File: internal/configs/version2/templates_test.go
- Add new policy fields to test data structs
- Run
make test-update-snapsto regenerate snapshots - Verify generated NGINX config in
__snapshots__/
Step 11: Update the Helm chart (if policy needs CLI flag or ConfigMap entry)
charts/nginx-ingress/values.yaml-- add value with##doccharts/nginx-ingress/values.schema.json-- add schema entrycharts/nginx-ingress/templates/_helpers.tpl-- add CLI arg or ConfigMap keycharts/tests/testdata/-- add test values filecharts/tests/helmunit_test.go-- add test case
Step 12: Add controller support
File: internal/k8s/
- In
syncPolicy(), ensure the new type is handled for VS/VSR/Ingress - Check if it needs feature-gate guarding (isPlus, enableOIDC, etc.)
Step 13: Write integration tests
Directory: tests/suite/
- Create test data YAMLs in
tests/data/<feature>/ - Create
test_<feature>_policies_vs.py,_vsr.py,_ingress.py - Use
@pytest.mark.policiesand@pytest.mark.policies_<feature>markers
Gotchas
- Never skip
make update-codegenafter changingtypes.go-- the build will fail with missing DeepCopy methods - Never use raw user strings in NGINX config without
containsDangerousChars()validation - Both OSS and Plus templates must be updated -- they are separate files
policiesCfgduplicate check must warn and return, not error (exception:addCORSConfighas no duplicate check -- it overwrites, since CORS is additive via headers)
Policy add*Config() Pattern
Every add*Config() method in internal/configs/policy.go follows this pattern:
func (p *policiesCfg) addMyPolicyConfig(spec *conf_v1.MyPolicy, key, namespace string,
secretRefs map[string]*secrets.SecretReference) *validationResults {
res := newValidationResults()
// 1. Duplicate check
if p.MyPolicy != nil {
res.addWarningf("MyPolicy policy already configured, ignoring")
return res
}
// 2. Secret resolution (if applicable)
secretKey := namespace + "/" + spec.Secret
secretRef := secretRefs[secretKey]
if secretRef.Error != nil {
res.isError = true
res.addWarningf("secret %s has error: %v", secretKey, secretRef.Error)
return res
}
if secretRef.Type != secrets.SecretTypeExpected {
res.isError = true
res.addWarningf("secret %s has wrong type", secretKey)
return res
}
// 3. Build template struct and assign
p.MyPolicy = &version2.MyPolicyConfig{
Field1: spec.Field1,
Field2: spec.Field2,
Secret: secretRef.Path,
}
return res
}
NGINX Template Pattern
{{- with $s.MyPolicy }}
my_directive {{ .Value }};
{{- if .OptionalField }}
my_optional_directive {{ .OptionalField }};
{{- end }}
{{- end }}