actors: Add pre-made HTTP actors

actors/http.go

@@ -0,0 +1,133 @@
+package http
+
+import "fmt"
+import "log"
+import "errors"
+import "context"
+import "net/http"
+import cf "git.tebibyte.media/sashakoshka/camfish"
+
+var _ cf.Actor           = new(HTTP)
+var _ cf.RunShutdownable = new(HTTP)
+var _ cf.Configurable    = new(HTTP)
+var _ cf.Initializable   = new(HTTP)
+
+// HTTP is an actor providing an HTTP server. Its configuration options are
+// as follows:
+//
+//   - http.address:   The host:port to serve on
+//   - http.cert-file: The location of the public TLS/SSL certificate
+//   - http.key-file:  The location of the private TLS/SSL key
+//
+// If neither cert-file nor key-file are specified, the actor will serve
+// over HTTPS instead of HTTP.
+type HTTP struct {
+	// Typ determines the actor's type. If empty, it defaults to "http".
+	// Once the actor has been used in any way at all, this field must
+	// never be modified.
+	Typ string
+	// Handler is used to handle HTTP requests. If nil, the server will
+	// respond with a "404 Not found" error.
+	// Once the actor has been used in any way at all, this field must
+	// never be modified.
+	Handler http.Handler
+	// DefaultAddr specifies the default address to serve on if none is
+	// specified. This itself defaults to localhost:8080.
+	DefaultAddr
+	
+	server  *http.Server	
+	address  string
+	certFile string
+	keyFile  string
+}
+
+// Type returns "http", or this.Typ if specified.
+func (this *HTTP) Type() string {
+	if this.Typ == "" {
+		return "http"
+	}
+	return this.Typ
+}
+
+// Configure configures the actor.
+func (this *HTTP) Configure(conf cf.Config) error {
+	{
+		value := conf.Get(this.Type() + ".address")
+		if value == "" {
+			if this.DefaultAddr == "" {
+				value = "localhost:8080"
+			} else {
+				value = this.DefaultAddr
+		}
+		this.address = value
+	}
+	{
+		certFile := this.Type() + "cert-file"
+		keyFile  := this.Type() + "key-file"
+		this.certFile = conf.Get(certFile)
+		this.keyFile = conf.Get(keyFile)
+		if this.certFile == "" && this.keyFile != "" ||
+			this.certFile != "" && this.keyFile == "" {
+			return fmt.Errorf(
+				"both %s and %s http.key-file must be specified, or neither",
+				this.certFile,
+				this.keyFile)
+		}
+	}
+	return nil
+}
+
+// Init initializes the actor.
+func (this *HTTP) Init(ctx context.Context) error {
+	this.server = &http.Server {
+		Addr:    this.address,
+		Handler: this.Handler,
+	}
+	return ctx.Err()
+}
+
+// Run runs the actor.
+func (this *HTTP) Run() error {
+	log.Printf("(i) [%s] listening on %s", this.Type(), this.address)
+	err := this.server.ListenAndServe()
+	if errors.Is(err, http.ErrServerClosed) { return nil }
+	return err
+}
+
+// Shutdown shuts down the actor.
+func (this *HTTP) Shutdown(ctx context.Context) error {
+	return this.server.Shutdown(ctx)
+}
+
+var _ cf.Actor           = new(HTTPServer)
+var _ cf.RunShutdownable = new(HTTPServer)
+var _ cf.Initializable   = new(HTTPServer)
+
+// HTTPServer lets you use a pre-existing [http.Server] as an actor. It has
+// no configuration or anything.
+type HTTPServer struct {
+	// Server must be non-nil.
+	*HTTP.Server
+	
+	// Typ determines the actor's type. If empty, it defaults to "http".
+	// Once the actor has been used in any way at all, this field must
+	// never be modified.
+	Typ string
+}
+
+
+// Type returns "http", or this.Typ if specified.
+func (this *HTTPServer) Type() string {
+	if this.Typ == "" {
+		return "http"
+	}
+	return this.Typ
+}
+
+// Run runs the actor.
+func (this *HTTPServer) Run() error {
+	log.Printf("(i) [%s] listening on %s", this.Type(), this.Addr)
+	err := this.server.ListenAndServe()
+	if errors.Is(err, http.ErrServerClosed) { return nil }
+	return err
+}