refactor(api): restructured API for type safety, maintainability and docs generation

- These changes makes the API incombatible with previous versions
- Added new types for error handling, success responses, and health checks.
- Updated health check logic to utilize the new types for better clarity and structure.
- Refactored existing handlers to improve response consistency and error handling.
- Updated Makefile to include a new target for generating API types from Swagger.
- Updated "new agent" API to respond an encrypted cert pair

internal/api/v1/docker/utils.go

@@ -0,0 +1,121 @@
+package dockerapi
+
+import (
+	"context"
+	"net/http"
+	"time"
+
+	"github.com/gin-gonic/gin"
+	"github.com/yusing/go-proxy/agent/pkg/agent"
+	apitypes "github.com/yusing/go-proxy/internal/api/types"
+	config "github.com/yusing/go-proxy/internal/config/types"
+	"github.com/yusing/go-proxy/internal/docker"
+	"github.com/yusing/go-proxy/internal/gperr"
+	"github.com/yusing/go-proxy/internal/net/gphttp/httpheaders"
+	"github.com/yusing/go-proxy/internal/net/gphttp/websocket"
+)
+
+type (
+	DockerClients     map[string]*docker.SharedClient
+	ResultType[T any] interface {
+		map[string]T | []T
+	}
+)
+
+// getDockerClients returns a map of docker clients for the current config.
+//
+// Returns a map of docker clients by server name and an error if any.
+//
+// Even if there are errors, the map of docker clients might not be empty.
+func getDockerClients() (DockerClients, gperr.Error) {
+	cfg := config.GetInstance()
+
+	dockerHosts := cfg.Value().Providers.Docker
+	dockerClients := make(DockerClients)
+
+	connErrs := gperr.NewBuilder("failed to connect to docker")
+
+	for name, host := range dockerHosts {
+		dockerClient, err := docker.NewClient(host)
+		if err != nil {
+			connErrs.Add(err)
+			continue
+		}
+		dockerClients[name] = dockerClient
+	}
+
+	for _, agent := range agent.ListAgents() {
+		dockerClient, err := docker.NewClient(agent.FakeDockerHost())
+		if err != nil {
+			connErrs.Add(err)
+			continue
+		}
+		dockerClients[agent.Name] = dockerClient
+	}
+
+	return dockerClients, connErrs.Error()
+}
+
+func getDockerClient(server string) (*docker.SharedClient, bool, error) {
+	cfg := config.GetInstance()
+	var host string
+	for name, h := range cfg.Value().Providers.Docker {
+		if name == server {
+			host = h
+			break
+		}
+	}
+	if host == "" {
+		for _, agent := range agent.ListAgents() {
+			if agent.Name == server {
+				host = agent.FakeDockerHost()
+				break
+			}
+		}
+	}
+	if host == "" {
+		return nil, false, nil
+	}
+	dockerClient, err := docker.NewClient(host)
+	if err != nil {
+		return nil, false, err
+	}
+	return dockerClient, true, nil
+}
+
+// closeAllClients closes all docker clients after a delay.
+//
+// This is used to ensure that all docker clients are closed after the http handler returns.
+func closeAllClients(dockerClients DockerClients) {
+	for _, dockerClient := range dockerClients {
+		dockerClient.Close()
+	}
+}
+
+func handleResult[V any, T ResultType[V]](c *gin.Context, errs error, result T) {
+	if errs != nil {
+		if len(result) == 0 {
+			c.Error(apitypes.InternalServerError(errs, "docker errors"))
+			return
+		}
+	}
+	c.JSON(http.StatusOK, result)
+}
+
+func serveHTTP[V any, T ResultType[V]](c *gin.Context, getResult func(ctx context.Context, dockerClients DockerClients) (T, gperr.Error)) {
+	dockerClients, err := getDockerClients()
+	if err != nil {
+		handleResult[V, T](c, err, nil)
+		return
+	}
+	defer closeAllClients(dockerClients)
+
+	if httpheaders.IsWebsocket(c.Request.Header) {
+		websocket.PeriodicWrite(c, 5*time.Second, func() (any, error) {
+			return getResult(c.Request.Context(), dockerClients)
+		})
+	} else {
+		result, err := getResult(c.Request.Context(), dockerClients)
+		handleResult[V](c, err, result)
+	}
+}