Declarative Configuration Reference Guide | MuleSoft Documentation
# Declarative Configuration Reference Guide
Anypoint Flex Gateway running in Local Mode supports two configuration models:
  * The resource-based model, common in Kubernetes, is ideal for granular definitions. Resources each contain one of the following values for configuration `kind`:
    * `ApiInstance`
    * `Service`
    * `PolicyBinding`
    * `Configuration`
  * The inline model is ideal for concise definitions, but is less versatile (for example, automated policies can only be applied in resource-based definitions.)
Inline definitions contain a single `ApiInstance` value for configuration `kind`, under which services and policies are both defined.


Refer to the Examples section for examples of both.
This reference guide describes the available resources that are applicable to either resource-based configurations or inline configurations.
## API Instance
```
apiVersion: gateway.mulesoft.com/v1alpha1
kind: ApiInstance
metadata:
 name: <api instance name>
 namespace: # optional namespace name
spec:
 address: <proxy address including port and path>
 services: # optional map of upstream services
  <name>:
   address: <service address>
   routes: # optional array of routes to service
    - config: # optional route configuration
      destinationPath: <optional base path to upstream service>
     rules: # optional route rules
 policies: # optional array of policies
  - policyRef:
    name: <name of the policy>
    namespace: <optional namespace of the policy>
   config: # optional policy configuration
   rules: # optional policy rules
```

Parameter | Required or Optional | Default Value | Description  
---|---|---|---  
`metadata.name` | Required | The API instance identifier that is used as a target reference for other resources, such as policy bindings.  
`metadata.namespace` | Optional  
`spec.address` | Required | The proxy address URL, including protocol, host, port and optional path. If the base path is specified, it must be absent in any `rules.path` attribute. Supported format: `protocol://host:port/path`, where `path` is optional, and `protocol` is either `http` or `https`.  
`spec.services` | Optional | A map of named services and their routes.  
`spec.services[name].address` | Required | The service address (and port). Supported format: `protocol://host:port`, where `protocol` is either `http` or `https`.  
`spec.services[name].routes` | Optional | An array of routes configured for this API instance towards the service. If left empty, a default route will be established to the service that will route all traffic.  
`spec.services[name].routes[#].config` | Optional | The configuration for this route. If left empty, a default configuration will be applied with an empty `destinationPath`.  
`spec.services[name].routes[#].config.destinationPath` | Optional | The path to prepend to forwarded requests to the upstream service. For example, if "destinationPath: /api/v1", requests to this API instance with a path like "/orders" will be routed upstream to "/api/v1/orders".  
`spec.services[name].routes[#].rules` | Optional | An array of rules for this route. Refer to spec.rules in Policy Binding.  
`spec.policies` | Optional | An array of policies to apply to this API Instance.  
`spec.policies[#].policyRef.name` | Required | The policy name.  
`spec.policies[#].policyRef.namespace` | Optional | The value of `metadata.namespace` | The namespace where the policy is defined. For provided policies, the value of this field should be `default`.  
`spec.policies[#].config` | Optional | The policy’s configuration. Refer to spec.config in Policy Binding. To use environment variables in `policies[#].config` fields, refer to Environment Variables for Policy Bindings.  
`spec.policies[#].rules` | Optional | An array of rules for applying this policy to the API Instance. spec.rules in Policy Binding.  
### API Instance Examples
The following resource specifies an `ApiInstance` with metadata that describes the instance identifier. The `metadata.name` value is used as the target reference for other resources, such as policy bindings. The `spec.services.routes.config.destinationPath` value prepends `/v1/apps` to the specified paths under `rules`, acting in a similar manner as a base path.
```
apiVersion: gateway.mulesoft.com/v1alpha1
kind: ApiInstance
metadata:
 name: hello-flex-gateway-instance
spec:
 address: http://0.0.0.0:8080
 services:
  json:
   address: https://<upstream address>:443/
   routes:
    - rules:
      - path: /api(/users/.*)
      - path: /api(/comments/.*)
     config:
      destinationPath: /v1/apps
```

#### Port Sharing
The following `ApiInstance` resources demonstrate API port sharing, with two distinct API instances listening on port 8080.
```
---
apiVersion: gateway.mulesoft.com/v1alpha1
kind: ApiInstance
metadata:
 name: httpbin-example
spec:
 address: http://0.0.0.0:8080/api/httpbin/
 services:
  upstream:
   address: https://<upstream address>:443
---
apiVersion: gateway.mulesoft.com/v1alpha1
kind: ApiInstance
metadata:
 name: json-example
spec:
 address: http://0.0.0.0:8080/api/json/
 services:
  upstream:
   address: https://<upstream address>:443
```

Both services listen on port 8080, for example:
```
curl http://localhost:8080/api/httpbin/get -v
curl http://localhost:8080/api/json/users/1 -v
```

The base path of APIs sharing a port must not clash. For example, the following path combination is not allowed: ```
http://0.0.0.0:8080/cats
http://0.0.0.0:8080/cats/dogs
```
  
---  
TLS applies to the port. Therefore, the same TLS policy applies to all API instances sharing the port.  
---  
## Policy Binding
```
apiVersion: gateway.mulesoft.com/v1alpha1
kind: PolicyBinding
metadata:
 name: <policy binding name>
 namespace: <namespace name>
spec:
 targetRef:
  name: <name of api instance or upstream service>
  namespace: <optional namespace of api instance or upstream service>
 policyRef:
  name: <policy name>
  namespace: <optional policy namespace>
 config: # optional policy configuration
 order: # optional policy read order
 rules: # optional policy rules
 - path: <path regular expression>
  methods: <methods regular expression>
  host: <host regular expression>
  headers: <headers map>
   <header-name>: <header value regular expression>
```
Both services listen on port 8080, for example:
```
curl http://localhost:8080/api/httpbin/get -v
curl http://localhost:8080/api/json/users/1 -v
```

The base path of APIs sharing a port must not clash. For example, the following path combination is not allowed: ```
http://0.0.0.0:8080/cats
http://0.0.0.0:8080/cats/dogs
```
  
---  
TLS applies to the port. Therefore, the same TLS policy applies to all API instances sharing the port.  
---  
## Policy Binding
```
apiVersion: gateway.mulesoft.com/v1alpha1
kind: PolicyBinding
metadata:
 name: <policy binding name>
 namespace: <namespace name>
spec:
 targetRef:
  name: <name of api instance or upstream service>
  namespace: <optional namespace of api instance or upstream service>
 policyRef:
  name: <policy name>
  namespace: <optional policy namespace>
 config: # optional policy configuration
 order: # optional policy read order
 rules: # optional policy rules
 - path: <path regular expression>
  methods: <methods regular expression>
  host: <host regular expression>
  headers: <headers map>
   <header-name>: <header value regular expression>
```

Parameter | Required or Optional | Default Value | Description  
---|---|---|---  
`metadata.name` | Required | The identifier of the policy binding.  
`metadata.namespace` | Optional  
`spec.targetRef.name` | Required | The API instance or upstream service identifier to which the policy is bound.  
`spec.targetRef.namespace` | Optional | The value of `metadata.namespace` | The namespace where the target is defined.  
`spec.policyRef.name` | Required | The policy name. See the list of available policies.  
`spec.policyRef.namespace` | Optional | The value of `metadata.namespace` | The namespace where the policy is defined. For provided policies, the value of this field should be `default`.  
`spec.config` | Optional | The policy configuration. The content of this field depends on the specified policy. See the list of available policies. To use environment variables in `config` fields, refer to Environment Variables for Policy Bindings.  
`spec.order` | Optional | The policy read order in the overall policy execution chain.  
`spec.rules` | Optional | An array of rules that will determine if the policy applies to a given request. These rules are checked in an OR fashion. The first one to hold will enable applying the policy to the request. The attributes in each rule object apply in an AND fashion. If path and host are defined, both must match for that rule to hold true.  
`spec.rules[#].path` | Optional | A regular expression to match the request path. Capture groups in this regular expression will be used to define path rewriting when routing the request upstream. If "path: /api(/.*)", requests with the path /api/orders will be routed upstream as /orders. Multiple capture groups can be specified, and the replacement will be the concatenation of all captured substrings.  
`spec.rules[#].host` | Optional | A regular expression to match the request host.  
`spec.rules[#].methods` | Optional | A regular expression to match the request method.  
`spec.rules[#].headers` | Optional | A map of header names and value regular expressions that must be present in the request. Each entry’s key is the expected header name and the value is a regular expression to match the header value.  
### Policy Binding Examples
The following resource binds a `route` policy to the API instance, routing traffic specified by the `rules` to the proxy address specified in the `Service` configuration snippet:
```
apiVersion: gateway.mulesoft.com/v1alpha1
kind: PolicyBinding
metadata:
 name: hello-flex-gateway-route
 namespace: e-commerce
spec:
 targetRef:
  name: hello-flex-gateway-instance
 policyRef:
  name: route
  namespace: default
 config:
  destinationRef:
   name: json
   namespace: e-commerce
 rules:
 - path: /api/json(/.*)
```

The following resource binds a `http-basic-authentication-flex` policy to the API instance - requiring requests to include the basic credentials defined in `config.username` and `config.password`. The policy is given a read order value of `2`.
```
apiVersion: gateway.mulesoft.com/v1alpha1
kind: PolicyBinding
metadata:
 name: hello-flex-gateway-auth
 namespace: e-commerce
spec:
 targetRef:
  name: hello-flex-gateway-instance
  namespace: e-commerce
 policyRef:
  name: http-basic-authentication-flex
  namespace: default
 config:
  username: chris
  password: admin
 order: 2
```

### Environment Variables for Policy Bindings
Both policy binding resources and inline policy bindings support environment variables in `config` fields. The environment variables available are dependent on your environment.
To reference your environment variable, specify your environment variable prefixed by `$`, for example:
```
- policyRef:
  name: http-basic-authentication-flex
 config:
  username: $USERNAME
  password: $PASSWORD
```

## Service
```
apiVersion: gateway.mulesoft.com/v1alpha1
kind: Service
metadata:
 name: <service name>
 namespace: <namespace name>
spec:
 address: <service address including port>
```

Parameter | Required or Optional | Default Value | Description  
---|---|---|---  
`metadata.name` | Required | The service identifier.  
`metadata.namespace` | Optional  
`spec.address` | Required | The service address URL, including protocol, host and port. Supported format: `protocol://host:port`, where `protocol` is either `http` or `https`.  
### Service Example
The following resource defines a `Service` with metadata that describes the service identifier. The `metadata.namespace` value matches the namespace specified in the `ApiInstance` configuration. The `spec.address` is the address of the API implementation:
```
apiVersion: gateway.mulesoft.com/v1alpha1
kind: Service
metadata:
 name: json-example
 namespace: e-commerce
spec:
 address: https://<upstream address>:443/
```

## Configuration
Define a desired gateway state by creating a `Configuration` entity. `Configuration` entities specify several runtime configuration aspects for Flex Gateway itself, such as logging and shared storage. The definition includes the following:
```
apiVersion: gateway.mulesoft.com/v1alpha1
kind: Configuration
metadata:
 name: <value>
 namespace: <namespace name>
spec:
 logging: # logging configuration
 sharedStorage: # shared storage configuration
```

Parameter | Required or Optional | Default Value | Description  
---|---|---|---  
`metadata.name` | Required | The Configuration entity.  
`metadata.namespace` | Optional | The namespace value used to isolate Configuration entities.  
Required | The configuration object that defines gateway characteristics. Objects include: `logging`, `sharedStorage`, `tls`.  
### Logging
The `logging` object configures the delivery of runtime and access logs enabled via the message logging policy. Logs are delivered to any supported Fluent Bit v3.2.10 output.
```
apiVersion: gateway.mulesoft.com/v1alpha1
kind: Configuration
metadata:
 name: <value>
 namespace: <namespace name>
spec:
 logging:
  outputs:
  - name: <output-name>
   type: <output-type>
   parameters:
    <param-name>: <param-value>
  runtimeLogs:
   logLevel: <value>
   outputs: <value>
  accessLogs:
   outputs: <value>
```
## Configuration
Define a desired gateway state by creating a `Configuration` entity. `Configuration` entities specify several runtime configuration aspects for Flex Gateway itself, such as logging and shared storage. The definition includes the following:
```
apiVersion: gateway.mulesoft.com/v1alpha1
kind: Configuration
metadata:
 name: <value>
 namespace: <namespace name>
spec:
 logging: # logging configuration
 sharedStorage: # shared storage configuration
```

Parameter | Required or Optional | Default Value | Description  
---|---|---|---  
`metadata.name` | Required | The Configuration entity.  
`metadata.namespace` | Optional | The namespace value used to isolate Configuration entities.  
Required | The configuration object that defines gateway characteristics. Objects include: `logging`, `sharedStorage`, `tls`.  
### Logging
The `logging` object configures the delivery of runtime and access logs enabled via the message logging policy. Logs are delivered to any supported Fluent Bit v3.2.10 output.
```
apiVersion: gateway.mulesoft.com/v1alpha1
kind: Configuration
metadata:
 name: <value>
 namespace: <namespace name>
spec:
 logging:
  outputs:
  - name: <output-name>
   type: <output-type>
   parameters:
    <param-name>: <param-value>
  runtimeLogs:
   logLevel: <value>
   outputs: <value>
  accessLogs:
   outputs: <value>
```

Parameter | Required or Optional | Default Value | Description  
---|---|---|---  
`logging.outputs[#].name` | Required | The name of this output to later refer to in runtime and access logs configurations.  
`logging.outputs[#].type` | Required | An output type supported by Fluent Bit. For Fluent Bit output types, see Fluent Bit documentation for your Fluent Bit version.  
`logging.outputs[#].parameters` | Required | A map of parameters for the specific Fluent Bit output type. For Fluent Bit output type parameters, see Fluent Bit documentation for your Fluent Bit version.  
`logging.accessLogs.outputs` | Optional | A list of output names to redirect access logs to.  
`logging.runtimeLogs.logLevel` | Optional | A parameter specifying log detail. The supported `logLevel` types listed in decreasing verbosity are `debug`, `info`, `warn`, `error`, and `fatal`.  
`logging.runtimeLogs.outputs` | Optional | A list of output names to redirect runtime logs to.  
Leaving a value blank applies the default value to your configuration.
In addition to parameters above, Flex Gateway offers variables for logging output. When configured, the variables render as one of their respective outputs in the logs:
Variable | Description | Outputs  
---|---|---  
Date and time of the logged event | A specific time, for example, `17/11/2022-09:48:27AM`  
Flex Gateway service where the logged event occurred | `flex-gateway-agent`, `flex-gateway-envoy`, and `flex-gateway-fluent`  
`Loglevel` of the logged event | `debug`, `info`, `warn`, `error`, or `fatal`  
Log type | `runtimeLog` or `accessLog`  
#### Logging Example
```
apiVersion: gateway.mulesoft.com/v1alpha1
kind: Configuration
metadata:
 name: logging
spec:
 logging:
  outputs:
  - name: log-to-file
   type: file
   parameters:
    path: /var/log
    file: log.txt
    format: template
    template: |
     [{date}][{logger}][{level}][{kind}] {message}
  runtimeLogs:
   logLevel: info
   outputs:
   - log-to-file
  accessLogs:
   outputs:
   - log-to-file
```

### Shared Storage
The `sharedStorage` object configures the gateway for shared storage. Production workflows should use Redis (minimum version 4.0.0), though defining it is optional. If Redis is not defined, shared storage services at port 4000 are still available but will use an in-memory implementation.
Optionally, you can use Redis with Transport Layer Security (TLS) to protect sensitive data, prevent unauthorized access, and maintain the reliability of your services.
```
apiVersion: gateway.mulesoft.com/v1alpha1
kind: Configuration
metadata:
 name: shared-storage-redis
spec:
 sharedStorage:
  redis:
   address: <string> // REQUIRED
   username: <string> // OPTIONAL
   password: <string> // OPTIONAL
   db: <string> // OPTIONAL
   tls: // OPTIONAL
    trustedCA: <string> // OPTIONAL
    certificate: // OPTIONAL
     keyPassphrase <string> // OPTIONAL
     key: <string> // REQUIRED
     crt: <string> // REQUIRED
    alpn: <array> // OPTIONAL
    skipValidation: <boolean> // OPTIONAL
    minversion: <string> // OPTIONAL
    maxversion: <string> // OPTIONAL
    ciphers: <array> // OPTIONAL
```

Parameter | Required or Optional | Default Value | Description  
---|---|---|---  
`sharedStorage.redis.address` | Required | The Redis instance address in `host:port` format  
`sharedStorage.redis.username` | Optional | The Redis user name  
`sharedStorage.redis.password` | Optional | The Redis user password  
`sharedStorage.redis.db` | Optional | The Redis database number to use  
`sharedStorage.redis.tls` | Optional | The Redis TLS configuration  
`sharedStorage.redis.tls.trustedCA` | Optional | Root certificate authority to use when verifying server certificates  
`sharedStorage.redis.tls.certificate` | Optional | Client certificate to present to the server  
`sharedStorage.redis.tls.keyPassphrase` | Optional | The certificate key passphrase. If specified, use the private key format that includes a DEK-Info header. If unspecified, the private key must not be encrypted.  
`sharedStorage.redis.tls.certificate.key` | Required | The private key part of the certificate  
`sharedStorage.redis.tls.certificate.crt` | Required | The public key part of the certificate  
`sharedStorage.redis.tls.skipValidation` | Optional | If true, any certificate presented by the server is accepted.  
`sharedStorage.redis.tls.minversion` | Optional | The minimum TLS version allowed  
`sharedStorage.redis.tls.maxversion` | Optional | The maximum TLS version allowed  
`sharedStorage.redis.tls.alpn` | Optional | Empty list | A prioritized list of supported application level protocols; for example, h2, http/1.1  
`sharedStorage.redis.tls.ciphers` | Optional  
TLS/Redis supports the same ciphers as the TLS policy, except the following:
  * TLS_RSA_WITH_NULL_SHA
  * TLS_PSK_WITH_AES_256_CBC_SHA
  * TLS_ECDHE_PSK_WITH_AES_128_CBC_SHA
  * TLS_ECDHE_PSK_WITH_AES_256_CBC_SHA
  * TLS_ECDHE_PSK_WITH_CHACHA20_POLY1305_SHA256

  
---  
**Redis Shared Storage Example**
The Redis storage service is an implementation of a REST API object store that functions as a bridge between the object store interface and a Redis backend.
```
apiVersion: gateway.mulesoft.com/v1alpha1
kind: Configuration
metadata:
 name: shared-storage-redis
spec:
 sharedStorage:
  redis:
   address: redis.e-commerce.svc:6379
   username: ecomm-user
   password: ecomm-pwd-123
   DB: 7
```
---  
**Redis Shared Storage Example**
The Redis storage service is an implementation of a REST API object store that functions as a bridge between the object store interface and a Redis backend.
```
apiVersion: gateway.mulesoft.com/v1alpha1
kind: Configuration
metadata:
 name: shared-storage-redis
spec:
 sharedStorage:
  redis:
   address: redis.e-commerce.svc:6379
   username: ecomm-user
   password: ecomm-pwd-123
   DB: 7
```

**Redis with TLS Shared Storage Example**
Optionally, you can use Redis with TLS to protect data and ensure secure communication.
```
apiVersion: gateway.mulesoft.com/v1alpha1
kind: Configuration
metadata:
 name: shared-storage-redis
spec:
 sharedStorage:
  redis:
   address: internal.redis.com:6379
   tls:
    skipValidation: false
    minVersion: "1.1"
    maxVersion: "1.3"
    alpn:
     - h2
     - http/1.1
    ciphers:
     - TLS_AES_128_GCM_SHA256
     - TLS_AES_256_GCM_SHA384
     - TLS_CHACHA20_POLY1305_SHA256
     - TLS_RSA_WITH_3DES_EDE_CBC_SHA
     - TLS_RSA_WITH_AES_128_CBC_SHA
     - TLS_RSA_WITH_AES_256_CBC_SHA
     - TLS_RSA_WITH_AES_128_CBC_SHA256
     - TLS_RSA_WITH_AES_128_GCM_SHA256
     - TLS_RSA_WITH_AES_256_GCM_SHA384
     - TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA
     - TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA
     - TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA
     - TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA
     - TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
     - TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
     - TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
     - TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384
     - TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256
     - TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256
    trustedCA: |
     -----BEGIN CERTIFICATE-----
     ...
     -----END CERTIFICATE-----
    certificate:
     keyPassphrase: "****"
     key: |
      -----BEGIN RSA PRIVATE KEY-----
      ...
      -----END RSA PRIVATE KEY-----
     crt: |
      -----BEGIN CERTIFICATE-----
      ...
      -----END CERTIFICATE-----
```

**Local Shared Storage Example**
The local storage service is an implementation of a REST API object store that saves data in memory. All data is lost when Flex Gateway is stopped or restarted.
```
apiVersion: gateway.mulesoft.com/v1alpha1
kind: Configuration
metadata:
 name: rtm-config
 namespace: sales
spec:
 sharedStorage:
  local:
   enabled: true
```

## Examples
### Inline Configuration Example
```
apiVersion: gateway.mulesoft.com/v1alpha1
kind: ApiInstance
metadata:
 name: api-example
spec:
 address: http://0.0.0.0:8080
 services:
  api-example:
   address: https://<your url>:443/
   routes:
    - rules:
      - path: /api(/users/.*)
      - path: /api(/comments/.*)
     config:
      destinationPath: /v1/apps
 policies:
  - policyRef:
    name: http-basic-authentication-flex
   config:
    username: chris
    password: admin
```

### Resource-Based Configuration Example
```
---
apiVersion: gateway.mulesoft.com/v1alpha1
kind: ApiInstance
metadata:
 name: ingress-http
spec:
 address: http://0.0.0.0:8080
---
apiVersion: gateway.mulesoft.com/v1alpha1
kind: Service
metadata:
 name: json
spec:
 address: https://<your url>:443/
---
apiVersion: gateway.mulesoft.com/v1alpha1
kind: PolicyBinding
metadata:
 name: ingress-http-route
spec:
 targetRef:
  name: ingress-http
 policyRef:
  name: route
 config:
  destinationRef:
   name: json
 rules:
 - path: /api(/users/.*)
 - path: /api(/comments/.*)
---
apiVersion: gateway.mulesoft.com/v1alpha1
kind: PolicyBinding
metadata:
 name: ingress-http-authentication
spec:
 targetRef:
  name: ingress-http
 policyRef:
  name: http-basic-authentication-flex
 config:
  username: chris
  password: admin
```