adds an alerts client

BACK-2500

alerts/client.go

@@ -0,0 +1,80 @@
+package alerts
+
+import (
+	"context"
+	"net/http"
+
+	"github.com/kelseyhightower/envconfig"
+
+	"github.com/tidepool-org/platform/client"
+	"github.com/tidepool-org/platform/platform"
+)
+
+// Client for managing alerts configs.
+type Client struct {
+	client *platform.Client
+}
+
+// NewClient builds an alerts client.
+func NewClient(cfg *ClientConfig) (*Client, error) {
+	client, err := platform.NewClient(cfg.Config, platform.AuthorizeAsService)
+	if err != nil {
+		return nil, err
+	}
+
+	return &Client{
+		client: client,
+	}, nil
+}
+
+// Upsert updates cfg in the service if it exists, or creates it if it doesn't.
+func (c *Client) Upsert(ctx context.Context, cfg *Config) error {
+	url := c.client.ConstructURL("v1", "alerts", cfg.UserID, cfg.FollowedUserID)
+	return c.client.RequestData(ctx, http.MethodPost, url, nil, cfg, nil)
+}
+
+// Delete the alerts config.
+func (c *Client) Delete(ctx context.Context, cfg *Config) error {
+	url := c.client.ConstructURL("v1", "alerts", cfg.UserID, cfg.FollowedUserID)
+	return c.client.RequestData(ctx, http.MethodDelete, url, nil, nil, nil)
+}
+
+// ClientConfig leverages platform.Config for the alerts client.
+type ClientConfig struct {
+	*platform.Config
+	Address string `envconfig:"TIDEPOOL_DATA_CLIENT_ADDRESS"`
+}
+
+// ConfigLoader abstracts the method by which config values are loaded.
+type ConfigLoader interface {
+	Load(cfg *ClientConfig) error
+}
+
+// envconfigLoader adapts envconfig to implement ConfigLoader.
+type envconfigLoader struct {
+	ConfigLoader platform.ConfigLoader
+}
+
+// NewEnvconfigLoader loads values via envconfig.
+//
+// If loader is nil, it defaults to envconfig for platform values.
+func NewEnvconfigLoader(loader platform.ConfigLoader) *envconfigLoader {
+	if loader == nil {
+		loader = platform.NewEnvconfigLoader(nil)
+	}
+	return &envconfigLoader{
+		ConfigLoader: loader,
+	}
+}
+
+// Load implements ConfigLoader.
+func (l *envconfigLoader) Load(cfg *ClientConfig) error {
+	if err := l.ConfigLoader.Load(cfg.Config); err != nil {
+		return err
+	}
+	if err := envconfig.Process(client.EnvconfigEmptyPrefix, cfg); err != nil {
+		return err
+	}
+	cfg.Config.Address = cfg.Address
+	return nil
+}

alerts/client_test.go

@@ -0,0 +1,78 @@
+package alerts
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+
+	"github.com/tidepool-org/platform/client"
+	"github.com/tidepool-org/platform/log"
+	"github.com/tidepool-org/platform/log/null"
+	"github.com/tidepool-org/platform/platform"
+)
+
+var _ = Describe("Client", func() {
+	test404Server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		http.Error(w, http.StatusText(http.StatusNotFound), http.StatusNotFound)
+	}))
+	GinkgoT().Cleanup(test404Server.Close)
+	test200Server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		http.Error(w, http.StatusText(http.StatusOK), http.StatusOK)
+	}))
+	GinkgoT().Cleanup(test200Server.Close)
+
+	Context("Delete", func() {
+		It("returns an error on non-200 responses", func() {
+			client, ctx := newAlertsClientTest(test404Server)
+			err := client.Delete(ctx, &Config{})
+			Expect(err).Should(HaveOccurred())
+			Expect(err).To(MatchError(ContainSubstring("resource not found")))
+		})
+
+		It("returns nil on success", func() {
+			client, ctx := newAlertsClientTest(test200Server)
+			err := client.Delete(ctx, &Config{})
+			Expect(err).ShouldNot(HaveOccurred())
+		})
+	})
+
+	Context("Upsert", func() {
+		It("returns an error on non-200 responses", func() {
+			client, ctx := newAlertsClientTest(test404Server)
+			err := client.Upsert(ctx, &Config{})
+			Expect(err).Should(HaveOccurred())
+			Expect(err).To(MatchError(ContainSubstring("resource not found")))
+		})
+
+		It("returns nil on success", func() {
+			client, ctx := newAlertsClientTest(test200Server)
+			err := client.Upsert(ctx, &Config{})
+			Expect(err).ShouldNot(HaveOccurred())
+		})
+	})
+
+})
+
+func buildTestClient(s *httptest.Server) *Client {
+	pCfg := &platform.Config{
+		ServiceSecret: "foo",
+		Config: &client.Config{
+			Address:   s.URL,
+			UserAgent: "foo",
+		},
+	}
+	client, err := NewClient(&ClientConfig{Address: s.URL, Config: pCfg})
+	Expect(err).ShouldNot(HaveOccurred())
+	return client
+}
+
+func newAlertsClientTest(server *httptest.Server) (*Client, context.Context) {
+	return buildTestClient(server), contextWithNullLogger()
+}
+
+func contextWithNullLogger() context.Context {
+	return log.NewContextWithLogger(context.Background(), null.NewLogger())
+}