make sentiment subscribe to posts to enrich

sentiment/subscriber/subscriber.go

@@ -0,0 +1,41 @@
+package subscriber
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	pb "github.com/micro/services/posts/proto"
+	"github.com/micro/services/sentiment/model"
+)
+
+var (
+	// assume this is initialised by main
+	PostsClient pb.PostsService
+)
+
+// EnrichPost will enrich a post with the sentiment and save it
+func EnrichPost(ctx context.Context, post *pb.Post) error {
+	if PostsClient == nil {
+		return nil
+	}
+
+	// start by analysing the title
+	// later we will look at the content
+	score := model.Analyze(post.Title)
+	post.Metadata["sentiment"] = fmt.Sprintf("%.1f", score)
+
+	// now save the post
+	PostsClient.Save(ctx, &pb.SaveRequest{
+		Id:        post.Id,
+		Title:     post.Title,
+		Content:   post.Content,
+		Timestamp: time.Now().Unix(),
+		Metadata:  post.Metadata,
+		Tags:      post.Tags,
+		Image:     post.Image,
+		Slug:      post.Slug,
+	})
+
+	return nil
+}