AzureFunctionService

Implements: IAzureFunctionService, IOpenable, IConfigurable, IReferenceable

Description

The AzureFunctionService class allows you to create a service that receives remove calls via the Azure Function protocol.

Important points

• This service is intended to work inside an AzureFunction container that exposes registered actions externally.

Configuration parameters

• dependencies:
  • controller: override for Controller dependency

References

• *:logger:*:*:1.0: (optional) ILogger components to pass log messages.
• *:counters:*:*:1.0: (optional) ICounters components to pass collected measurements.

Constructors

NewAzureFunctionService

Creates an instance of this service.

NewAzureFunctionService(name string) *AzureFunctionService

• name: string - a service name to generate action cmd.

InheritAzureFunctionService

InheritAzureFunctionService creates new instance of AzureFunctionService

InheritAzureFunctionService(overrides IAzureFunctionServiceOverrides, name string) *AzureFunctionService

• overrides: IAzureFunctionServiceOverrides - instance that overrides register method.
• name: string - a service name to generate action cmd.

Fields

Instance methods

ApplyInterceptors

Applies given action to the interceptors

(c *AzureFunctionService) ApplyInterceptors(action http.HandlerFunc) http.HandlerFunc

• action http.HandlerFunc - interceptor function.
• returns: http.HandlerFunc - wrapped interceptors action.

ApplyValidation

Performs a validation.

(c *AzureFunctionService) ApplyValidation(schema *Schema, action http.HandlerFunc) http.HandlerFunc

• schema: *Schema - schema used in the validation
• action: http.HandlerFunc - action
• returns: http.HandlerFunc - returned result

Close

Closes a component and frees used resources.

(c *AzureFunctionService) Close(ctx context.Context, correlationId string) error

• ctx: context.Context - operation context.
• correlationId: string - (optional) transaction id used to trace execution through the call chain.
• returns: error - close error.

Configure

Configures a component by passing its configuration parameters.

public configure(config: ConfigParams): void

• config: ConfigParams - configuration parameters to be set.

GenerateActionCmd

Adds ‘.cmd’ to a command name

(c *AzureFunctionService) GenerateActionCmd(name string) string

• name: string - command name
• returns: string - command name with ‘.cmd’ added at its end.

GetActions

Get all actions supported by the service.

(c *AzureFunctionService) GetActions() []*AzureFunctionAction

• returns: []*AzureFunctionAction - array with supported actions.

GetCommand

Returns a command from the Azure Function context.

This method can be overloaded in child classes.

(c *AzureFunctionService) GetCommand(r *http.Request) (string, error)

• r: *http.Request - context.
• returns: (string, error) - returned command from context.

GetCorrelationId

Returns a correlationId from the Azure Function context.

This method can be overloaded in child classes.

(c *AzureFunctionService) GetCorrelationId(r *http.Request) string

• r: *http.Request - request.
• returns: string - returned correlationId from context.

Instrument

Adds instrumentation to log calls and measures call time. It returns a Timing object that is used to end the time measurement.

(c *AzureFunctionService) Instrument(ctx context.Context, correlationId string, name string) *InstrumentTiming

• ctx: context.Context - operation context.
• correlationId: string - (optional) transaction id used to trace execution through the call chain.
• name: string - method’s name.
• returns: *InstrumentTiming - Timing object to end the time measurement.

IsOpen

Checks if the component is open.

(c *AzureFunctionService) IsOpen() bool

• returns: bool - true if the component is open and false otherwise.

Open

Opens the component.

(c *AzureFunctionService) Open(ctx context.Context, correlationId string) error

• ctx: context.Context - operation context.
• correlationId: string - (optional) transaction id used to trace execution through the call chain.
• returns: error - open error.

Register

Registers all service routes in an HTTP endpoint.

This method is called by the service and must be overridden in child classes.

(c *AzureFunctionService) Register()

RegisterAction

Registers an action in Azure Function function.

(c *AzureFunctionService) RegisterAction(name string, schema *cvalid.Schema, action http.HandlerFunc)

• name: string - action name
• schema: *Schema - validation schema used to validate received parameters.
• action: http.HandlerFunc - action function that is called when the operation is invoked.

RegisterActionWithAuth

Registers an action with authorization.

(c *AzureFunctionService) RegisterActionWithAuth(name string, schema *Schema, authorize func(w http.ResponseWriter, r *http.Request, next http.HandlerFunc), action http.HandlerFunc)

• name: string - action’s name
• schema: *Schema - validation schema used to validate received parameters.
• authorize: func(w http.ResponseWriter, r *http.Request, next http.HandlerFunc) - authorization interceptor
• action: http.HandlerFunc - action function that is called when the operation is invoked.

RegisterInterceptor

Registers a middleware for actions in Azure Function service.

(c *AzureFunctionService) RegisterInterceptor(cmd string, action func(w http.ResponseWriter, r *http.Request, next http.HandlerFunc))

• cmd: string - command name.
• action: func(w http.ResponseWriter, r *http.Request, next http.HandlerFunc) - action function that is called when middleware is invoked.

SetReferences

Sets references to dependent components.

(c *AzureFunctionService) SetReferences(ctx context.Context, references IReferences)

• ctx: context.Context - operation context.
• references: IReferences - references to locate the component’s dependencies.

Examples

type MyAzureFunctionService struct {
	*services.AzureFunctionService
	controller IMyController
}

func NewMyAzureFunctionService() *MyAzureFunctionService {
	c := MyAzureFunctionService{}

	c.AzureFunctionService = services.InheritAzureFunctionService(&c, "v1.myservice")
	c.DependencyResolver.Put(context.Background(), "controller", refer.NewDescriptor("mygroup", "controller", "default", "*", "1.0"))

	return &c
}

func (c *MyAzureFunctionService) SetReferences(ctx context.Context, references refer.IReferences) {
	c.AzureFunctionService.SetReferences(ctx, references)
	depRes, depErr := c.DependencyResolver.GetOneRequired("controller")

	if depErr == nil && depRes != nil {
		c.controller = depRes.(IMyController)
	}
}

func (c *MyAzureFunctionService) Register() {
	c.RegisterAction(
		"get_mydata",
		nil,
		func(w http.ResponseWriter, r *http.Request) {
			var body map[string]any

			err := AzureFunctionRequestHelper.DecodeBody(r, &body)
			defer r.Body.Close()

			result, err := c.controller.DeleteById(
				r.Context(),
				c.GetCorrelationId(r),
				body,
			)
			HttpResponseSender.SendDeletedResult(w, r, result, err)
		},
	)
}

...

service := NewMyAzureFunctionService()
service.Configure(ctx, config.NewConfigParamsFromTuples(
	"connection.protocol", "http",
	"connection.host", "localhost",
	"connection.port", 8080,
))

service.SetReferences(ctx, refer.NewReferencesFromTuples(
	refer.NewDescriptor("mygroup", "controller", "default", "default", "1.0"), controller,
))
service.Open(ctx, "123")
fmt.Println("The Azure Function service is running")