Add an example usage. Close #9

example/business/web_page_manager.go

@@ -0,0 +1,23 @@
+package business
+
+import (
+	"github.com/magic003/alice/example/client"
+	"github.com/magic003/alice/example/persist"
+)
+
+// WebPageManager manages web pages.
+type WebPageManager struct {
+	httpClient client.HTTPClient
+	webPageDao persist.WebPageDao
+}
+
+// NewWebPageManager returns a new instance of WebPageManager.
+func NewWebPageManager(httpClient client.HTTPClient, webPageDao persist.WebPageDao) *WebPageManager {
+	if httpClient == nil || webPageDao == nil {
+		panic("httpClient or webPageDao cannot be nil")
+	}
+	return &WebPageManager{
+		httpClient: httpClient,
+		webPageDao: webPageDao,
+	}
+}

example/client/http_client.go

@@ -0,0 +1,26 @@
+package client
+
+// HTTPClient is an interface for fetching web page.
+type HTTPClient interface {
+	// Fetch fetches a web page by url.
+	Fetch(url string) string
+}
+
+// NewHTTPClient returns an instance of HTTPClient.
+func NewHTTPClient(retries int) HTTPClient {
+	if retries <= 0 {
+		panic("retries should be greater than 0")
+	}
+	return &httpClient{
+		retries: retries,
+	}
+}
+
+// httpClient is a dummy implementation of HTTPClient.
+type httpClient struct {
+	retries int
+}
+
+func (client *httpClient) Fetch(url string) string {
+	return ""
+}

example/example_test.go

@@ -0,0 +1,28 @@
+package example
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/magic003/alice"
+	"github.com/magic003/alice/example/business"
+	"github.com/magic003/alice/example/module"
+)
+
+func TestExample(t *testing.T) {
+	c := alice.CreateContainer(
+		&module.ConfigModule{}, &module.PersistModule{}, &module.ClientModule{}, &module.BusinessModule{})
+
+	retries := c.InstanceByName("Retries")
+	if retries != 3 {
+		t.Errorf("bad retries: got %v, expected %v", retries, 3)
+	}
+
+	table := c.InstanceByName("Table")
+	if table != "example_table" {
+		t.Errorf("bad table: got %s, expected %s", table, "example_table")
+	}
+
+	// should not panic
+	c.Instance(reflect.TypeOf((*business.WebPageManager)(nil)))
+}

example/module/business_module.go

@@ -0,0 +1,20 @@
+package module
+
+import (
+	"github.com/magic003/alice"
+	"github.com/magic003/alice/example/business"
+	"github.com/magic003/alice/example/client"
+	"github.com/magic003/alice/example/persist"
+)
+
+// BusinessModule is the module for business objects.
+type BusinessModule struct {
+	alice.BaseModule
+	WebPageDao persist.WebPageDao `alice:""`
+	HTTPClient client.HTTPClient  `alice:"HTTPClient"`
+}
+
+// WebPageManager returns an instance of WebPageManager.
+func (m *BusinessModule) WebPageManager() *business.WebPageManager {
+	return business.NewWebPageManager(m.HTTPClient, m.WebPageDao)
+}

example/module/client_module.go

@@ -0,0 +1,17 @@
+package module
+
+import (
+	"github.com/magic003/alice"
+	"github.com/magic003/alice/example/client"
+)
+
+// ClientModule is the module for clients.
+type ClientModule struct {
+	alice.BaseModule
+	Retries int `alice:"Retries"`
+}
+
+// HTTPClient returns an instance fo HTTPClient.
+func (m *ClientModule) HTTPClient() client.HTTPClient {
+	return client.NewHTTPClient(m.Retries)
+}

example/module/config_module.go

@@ -0,0 +1,20 @@
+package module
+
+import (
+	"github.com/magic003/alice"
+)
+
+// ConfigModule is the module for configurations.
+type ConfigModule struct {
+	alice.BaseModule
+}
+
+// Retries returns the client retry attempts.
+func (m *ConfigModule) Retries() int {
+	return 3
+}
+
+// Table is the table name.
+func (m *ConfigModule) Table() string {
+	return "example_table"
+}

example/module/persist_module.go

@@ -0,0 +1,17 @@
+package module
+
+import (
+	"github.com/magic003/alice"
+	"github.com/magic003/alice/example/persist"
+)
+
+// PersistModule is the module for persistent APIs.
+type PersistModule struct {
+	alice.BaseModule
+	Table string `alice:"Table"`
+}
+
+// WebPageDao returns the WebPageDao.
+func (m *PersistModule) WebPageDao() persist.WebPageDao {
+	return persist.NewWebPageDao(m.Table)
+}

example/persist/web_page_dao.go

@@ -0,0 +1,32 @@
+package persist
+
+// WebPageDao defines the interface to access web pages saved in database.
+type WebPageDao interface {
+	// Find looks up a web page by url.
+	Find(url string) string
+	// Save saves a web page.
+	Save(url string, content string) error
+}
+
+// NewWebPageDao returns an instance of WebPageDao.
+func NewWebPageDao(table string) WebPageDao {
+	if table == "" {
+		panic("table cannot be empty")
+	}
+	return &webPageDao{
+		table: table,
+	}
+}
+
+// webPageDao is a dummy implementation for WebPageDao.
+type webPageDao struct {
+	table string
+}
+
+func (dao *webPageDao) Find(url string) string {
+	return ""
+}
+
+func (dao *webPageDao) Save(url string, content string) error {
+	return nil
+}