improvement(core): allow wildcard in first label in hostname

core/src/config/common.ts

@@ -118,6 +118,7 @@ export interface Schema extends Joi.Root {
   environment: () => Joi.StringSchema
   gitUrl: () => GitUrlSchema
   posixPath: () => PosixPathSchema
+  hostname: () => Joi.StringSchema
 }
 
 export let joi: Schema = Joi.extend({
@@ -354,6 +355,44 @@ joi = joi.extend({
   },
 })
 
+/**
+ * Add a joi.hostname() type. Like joi.string().hostname() with the exception that it allows
+ * wildcards in the first DNS label and returns a custom error if it finds wildcards in labels
+ * other than the first.
+ */
+joi = joi.extend({
+  base: Joi.string(),
+  type: "hostname",
+  messages: {
+    base: "{{#label}} must be a valid hostname.",
+    wildcardLabel: "{{#label}} only first DNS label my contain a wildcard.",
+  },
+  validate(value: string, { error }) {
+    const baseSchema = joi.string().hostname()
+    const wildcardLabel = "*."
+    let result: Joi.ValidationResult
+
+    const labels = value.split(".")
+    // Hostname includes a wildcard label that is not the first label
+    if (!value.startsWith(wildcardLabel) && labels.includes("*")) {
+      return { value, errors: error("wildcardLabel") }
+    }
+
+    if (value.startsWith(wildcardLabel)) {
+      const restLabels = value.slice(wildcardLabel.length)
+      result = baseSchema.validate(restLabels)
+    } else {
+      result = baseSchema.validate(value)
+    }
+
+    if (result.error) {
+      return { value, errors: error("base") }
+    }
+
+    return { value }
+  },
+})
+
 export const joiPrimitive = () =>
   joi
     .alternatives()

core/src/plugins/kubernetes/config.ts

@@ -264,7 +264,7 @@ const tlsCertificateSchema = () =>
       .example("wildcard"),
     hostnames: joi
       .array()
-      .items(joi.string().hostname())
+      .items(joi.hostname())
       .description(
         "A list of hostnames that this certificate should be used for. " +
           "If you don't specify these, they will be automatically read from the certificate."

core/src/types/service.ts

@@ -102,7 +102,7 @@ export interface ServiceIngress extends ServiceIngressSpec {
 }
 
 export const ingressHostnameSchema = () =>
-  joi.string().hostname().description(dedent`
+  joi.hostname().description(dedent`
     The hostname that should route to this service. Defaults to the default hostname configured in the provider configuration.
 
     Note that if you're developing locally you may need to add this hostname to your hosts file.

core/test/unit/src/config/common.ts

@@ -276,6 +276,24 @@ describe("joi.posixPath", () => {
   })
 })
 
+describe("joi.hostname", () => {
+  const schema = joi.hostname()
+
+  it("should accept valid hostnames", () => {
+    const result = schema.validate("foo.bar.bas")
+    expect(result.error).to.be.undefined
+  })
+  it("should accept hostnames with a wildcard in the first DNS label", () => {
+    const result = schema.validate("*.bar.bas")
+    expect(result.error).to.be.undefined
+  })
+  it("should reject hostnames with wildcard DNS labels that are not the first label", () => {
+    const result = schema.validate("foo.*.bas")
+    expect(result.error).to.exist
+    expect(result!.error!.message).to.eql(`"value" only first DNS label my contain a wildcard.`)
+  })
+})
+
 describe("joi.environment", () => {
   const schema = joi.environment()
 

docs/reference/module-types/container.md

@@ -1030,9 +1030,9 @@ The hostname that should route to this service. Defaults to the default hostname
 
 Note that if you're developing locally you may need to add this hostname to your hosts file.
 
-| Type     | Required |
-| -------- | -------- |
-| `string` | No       |
+| Type       | Required |
+| ---------- | -------- |
+| `hostname` | No       |
 
 ### `services[].ingresses[].linkUrl`
 

docs/reference/module-types/maven-container.md

@@ -1038,9 +1038,9 @@ The hostname that should route to this service. Defaults to the default hostname
 
 Note that if you're developing locally you may need to add this hostname to your hosts file.
 
-| Type     | Required |
-| -------- | -------- |
-| `string` | No       |
+| Type       | Required |
+| ---------- | -------- |
+| `hostname` | No       |
 
 ### `services[].ingresses[].linkUrl`