Rewrite emailservice in ruby

.env

@@ -30,7 +30,7 @@ CURRENCY_SERVICE_PORT=7000
 CURRENCY_SERVICE_ADDR=currencyservice:${CURRENCY_SERVICE_PORT}
 
 EMAIL_SERVICE_PORT=8080
-EMAIL_SERVICE_ADDR=emailservice:${EMAIL_SERVICE_PORT}
+EMAIL_SERVICE_ADDR=http://emailservice:${EMAIL_SERVICE_PORT}
 
 PAYMENT_SERVICE_PORT=50051
 PAYMENT_SERVICE_ADDR=paymentservice:${PAYMENT_SERVICE_PORT}

README.md

@@ -113,7 +113,7 @@ cache[(Cache<br/>&#40redis&#41)]
 cartservice(Cart Service<br/>&#40.NET&#41):::dotnet
 checkoutservice(Checkout Service<br/>&#40Go&#41):::golang
 currencyservice(Currency Service<br/>&#40Node.js&#41):::nodejs
-emailservice(Email Service<br/>&#40Python&#41):::python
+emailservice(Email Service<br/>&#40Ruby&#41):::ruby
 frontend(Frontend<br/>&#40Go&#41):::golang
 loadgenerator([Load Generator<br/>&#40Python&#41]):::python
 paymentservice(Payment Service<br/>&#40Node.js&#41):::nodejs
@@ -152,7 +152,7 @@ Find **Protocol Buffers Descriptions** at the [`./pb` directory](./pb/README.md)
 | [currencyservice](./src/currencyservice/README.md)             | Node.js       | Converts one money amount to another currency. Uses real values fetched from European Central Bank. It's the highest QPS service. |
 | [paymentservice](./src/paymentservice/README.md)               | Node.js       | Charges the given credit card info (mock) with the given amount and returns a transaction ID.                                     |
 | [shippingservice](./src/shippingservice/README.md)             | Go            | Gives shipping cost estimates based on the shopping cart. Ships items to the given address (mock)                                 |
-| [emailservice](./src/emailservice/README.md)                   | Python        | Sends users an order confirmation email (mock).                                                                                   |
+| [emailservice](./src/emailservice/README.md)                   | Ruby        | Sends users an order confirmation email (mock).                                                                                   |
 | [checkoutservice](./src/checkoutservice/README.md)             | Go            | Retrieves user cart, prepares order and orchestrates the payment, shipping and the email notification.                            |
 | [recommendationservice](./src/recommendationservice/README.md) | Python        | Recommends other products based on what's given in the cart.                                                                      |
 | [adservice](./src/adservice/README.md)                         | Java          | Provides text ads based on given context words.                                                                                   |

compose.yml

@@ -19,7 +19,7 @@ services:
 
   # Collector
   otelcol:
-    image: otel/opentelemetry-collector
+    image: otel/opentelemetry-collector:0.52.0
     command: [ "--config=/etc/otelcol-config.yml" ]
     volumes:
       - ./src/otelcollector/otelcol-config.yml:/etc/otelcol-config.yml
@@ -93,9 +93,9 @@ services:
     ports:
       - "${EMAIL_SERVICE_PORT}"
     environment:
+      - APP_ENV=production
       - PORT=${EMAIL_SERVICE_PORT}
-      - OTEL_PYTHON_LOG_CORRELATION=true
-      - OTEL_EXPORTER_OTLP_TRACES_ENDPOINT
+      - OTEL_EXPORTER_OTLP_TRACES_ENDPOINT=http://otelcol:4318/v1/traces
       - OTEL_RESOURCE_ATTRIBUTES=service.name=emailservice
 
   # Frontend

src/checkoutservice/go.mod

@@ -14,11 +14,15 @@ require (
 require (
 	cloud.google.com/go/compute v0.1.0 // indirect
 	github.com/cenkalti/backoff/v4 v4.1.2 // indirect
+	github.com/felixge/httpsnoop v1.0.2 // indirect
 	github.com/go-logr/logr v1.2.2 // indirect
 	github.com/go-logr/stdr v1.2.2 // indirect
 	github.com/golang/protobuf v1.5.2 // indirect
 	github.com/grpc-ecosystem/grpc-gateway v1.16.0 // indirect
+	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.29.0 // indirect
 	go.opentelemetry.io/otel/exporters/otlp/internal/retry v1.4.1 // indirect
+	go.opentelemetry.io/otel/internal/metric v0.27.0 // indirect
+	go.opentelemetry.io/otel/metric v0.27.0 // indirect
 	go.opentelemetry.io/otel/trace v1.4.1 // indirect
 	go.opentelemetry.io/proto/otlp v0.12.0 // indirect
 	golang.org/x/net v0.0.0-20220121210141-e204ce36a2ba // indirect

src/checkoutservice/go.sum

@@ -81,12 +81,16 @@ github.com/envoyproxy/go-control-plane v0.9.9-0.20210217033140-668b12f5399d/go.m
 github.com/envoyproxy/go-control-plane v0.9.9-0.20210512163311-63b5d3c536b0/go.mod h1:hliV/p42l8fGbc6Y9bQ70uLwIvmJyVE5k4iMKlh8wCQ=
 github.com/envoyproxy/go-control-plane v0.9.10-0.20210907150352-cf90f659a021/go.mod h1:AFq3mo9L8Lqqiid3OhADV3RfLJnjiw63cSpi+fDTRC0=
 github.com/envoyproxy/protoc-gen-validate v0.1.0/go.mod h1:iSmxcyjqTsJpI2R4NaDN7+kN2VEUnK/pcBlmesArF7c=
+github.com/felixge/httpsnoop v1.0.2 h1:+nS9g82KMXccJ/wp0zyRW9ZBHFETmMGtkk+2CTTrW4o=
+github.com/felixge/httpsnoop v1.0.2/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=
 github.com/ghodss/yaml v1.0.0/go.mod h1:4dBDuWmgqj2HViK6kFavaiC9ZROes6MMH2rRYeMEF04=
 github.com/go-gl/glfw v0.0.0-20190409004039-e6da0acd62b1/go.mod h1:vR7hzQXu2zJy9AVAgeJqvqgH9Q5CA+iKCZ2gyEVpxRU=
 github.com/go-gl/glfw/v3.3/glfw v0.0.0-20191125211704-12ad95a8df72/go.mod h1:tQ2UAYgL5IevRw8kRxooKSPJfGvJ9fJQFa0TUsXzTg8=
 github.com/go-gl/glfw/v3.3/glfw v0.0.0-20200222043503-6f7a984d4dc4/go.mod h1:tQ2UAYgL5IevRw8kRxooKSPJfGvJ9fJQFa0TUsXzTg8=
 github.com/go-logr/logr v1.2.2 h1:ahHml/yUpnlb96Rp8HCvtYVPY8ZYpxq3g7UYchIYwbs=
 github.com/go-logr/logr v1.2.2/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
+github.com/go-logr/logr v1.2.3 h1:2DntVwHkVopvECVRSlL5PSo9eG+cAkDCuckLubN+rq0=
+github.com/go-logr/logr v1.2.3/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
 github.com/go-logr/stdr v1.2.2 h1:hSWxHoqTgW2S2qGc0LTAI563KZ5YKYRhT3MFKZMbjag=
 github.com/go-logr/stdr v1.2.2/go.mod h1:mMo/vtBO5dYbehREoey6XUKy/eSumjCCveDpRre4VKE=
 github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b/go.mod h1:SBH7ygxi8pfUlaOkMMuAQtPIUF8ecWP5IEl/CR7VP2Q=
@@ -190,6 +194,8 @@ github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5
 github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.7.1 h1:5TQK59W5E3v0r2duFAb7P95B6hEeOyEnHRa8MjYSMTY=
+github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/yuin/goldmark v1.1.25/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 github.com/yuin/goldmark v1.1.27/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 github.com/yuin/goldmark v1.1.32/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
@@ -204,20 +210,34 @@ go.opencensus.io v0.22.5/go.mod h1:5pWMHQbX5EPX2/62yrJeAkowc+lfs/XD7Uxpq3pI6kk=
 go.opencensus.io v0.23.0/go.mod h1:XItmlyltB5F7CS4xOC1DcqMoFqwtC6OG2xF7mCv7P7E=
 go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.29.0 h1:n9b7AAdbQtQ0k9dm0Dm2/KUcUqtG8i2O15KzNaDze8c=
 go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.29.0/go.mod h1:LsankqVDx4W+RhZNA5uWarULII/MBhF5qwCYxTuyXjs=
+go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.29.0 h1:SLme4Porm+UwX0DdHMxlwRt7FzPSE0sys81bet2o0pU=
+go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.29.0/go.mod h1:tLYsuf2v8fZreBVwp9gVMhefZlLFZaUiNVSq8QxXRII=
+go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.32.0 h1:mac9BKRqwaX6zxHPDe3pvmWpwuuIM0vuXv2juCnQevE=
+go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.32.0/go.mod h1:5eCOqeGphOyz6TsY3ZDNjE33SM/TFAK3RGuCL2naTgY=
 go.opentelemetry.io/otel v1.4.0/go.mod h1:jeAqMFKy2uLIxCtKxoFj0FAL5zAPKQagc3+GtBWakzk=
 go.opentelemetry.io/otel v1.4.1 h1:QbINgGDDcoQUoMJa2mMaWno49lja9sHwp6aoa2n3a4g=
 go.opentelemetry.io/otel v1.4.1/go.mod h1:StM6F/0fSwpd8dKWDCdRr7uRvEPYdW0hBSlbdTiUde4=
+go.opentelemetry.io/otel v1.7.0 h1:Z2lA3Tdch0iDcrhJXDIlC94XE+bxok1F9B+4Lz/lGsM=
+go.opentelemetry.io/otel v1.7.0/go.mod h1:5BdUoMIz5WEs0vt0CUEMtSSaTSHBBVwrhnz7+nrD5xk=
 go.opentelemetry.io/otel/exporters/otlp/internal/retry v1.4.1 h1:imIM3vRDMyZK1ypQlQlO+brE22I9lRhJsBDXpDWjlz8=
 go.opentelemetry.io/otel/exporters/otlp/internal/retry v1.4.1/go.mod h1:VpP4/RMn8bv8gNo9uK7/IMY4mtWLELsS+JIP0inH0h4=
 go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.4.1 h1:WPpPsAAs8I2rA47v5u0558meKmmwm1Dj99ZbqCV8sZ8=
 go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.4.1/go.mod h1:o5RW5o2pKpJLD5dNTCmjF1DorYwMeFJmb/rKr5sLaa8=
 go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.4.1 h1:AxqDiGk8CorEXStMDZF5Hz9vo9Z7ZZ+I5m8JRl/ko40=
 go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.4.1/go.mod h1:c6E4V3/U+miqjs/8l950wggHGL1qzlp0Ypj9xoGrPqo=
+go.opentelemetry.io/otel/internal/metric v0.27.0 h1:9dAVGAfFiiEq5NVB9FUJ5et+btbDQAUIJehJ+ikyryk=
+go.opentelemetry.io/otel/internal/metric v0.27.0/go.mod h1:n1CVxRqKqYZtqyTh9U/onvKapPGv7y/rpyOTI+LFNzw=
+go.opentelemetry.io/otel/metric v0.27.0 h1:HhJPsGhJoKRSegPQILFbODU56NS/L1UE4fS1sC5kIwQ=
+go.opentelemetry.io/otel/metric v0.27.0/go.mod h1:raXDJ7uP2/Jc0nVZWQjJtzoyssOYWu/+pjZqRzfvZ7g=
+go.opentelemetry.io/otel/metric v0.30.0 h1:Hs8eQZ8aQgs0U49diZoaS6Uaxw3+bBE3lcMUKBFIk3c=
+go.opentelemetry.io/otel/metric v0.30.0/go.mod h1:/ShZ7+TS4dHzDFmfi1kSXMhMVubNoP0oIaBp70J6UXU=
 go.opentelemetry.io/otel/sdk v1.4.1 h1:J7EaW71E0v87qflB4cDolaqq3AcujGrtyIPGQoZOB0Y=
 go.opentelemetry.io/otel/sdk v1.4.1/go.mod h1:NBwHDgDIBYjwK2WNu1OPgsIc2IJzmBXNnvIJxJc8BpE=
 go.opentelemetry.io/otel/trace v1.4.0/go.mod h1:uc3eRsqDfWs9R7b92xbQbU42/eTNz4N+gLP8qJCi4aE=
 go.opentelemetry.io/otel/trace v1.4.1 h1:O+16qcdTrT7zxv2J6GejTPFinSwA++cYerC5iSiF8EQ=
 go.opentelemetry.io/otel/trace v1.4.1/go.mod h1:iYEVbroFCNut9QkwEczV9vMRPHNKSSwYZjulEtsmhFc=
+go.opentelemetry.io/otel/trace v1.7.0 h1:O37Iogk1lEkMRXewVtZ1BBTVn5JEp8GrJvP92bJqC6o=
+go.opentelemetry.io/otel/trace v1.7.0/go.mod h1:fzLSB9nqR2eXzxPXb2JW9IKE+ScyXA48yyE4TNvoHqU=
 go.opentelemetry.io/proto/otlp v0.7.0/go.mod h1:PqfVotwruBrMGOCsRd/89rSnXhoiJIqeYNgFYFoEGnI=
 go.opentelemetry.io/proto/otlp v0.12.0 h1:CMJ/3Wp7iOWES+CYLfnBv+DVmPbB+kmy9PJ92XvlR6c=
 go.opentelemetry.io/proto/otlp v0.12.0/go.mod h1:TsIjwGWIx5VFYv9KGVlOpxoBl5Dy+63SUguV7GGvlSQ=

src/checkoutservice/main.go

@@ -15,9 +15,12 @@
 package main
 
 import (
+	"bytes"
 	"context"
+	"encoding/json"
 	"fmt"
 	"net"
+	"net/http"
 	"os"
 	"time"
 
@@ -29,6 +32,7 @@ import (
 	"google.golang.org/grpc/status"
 
 	"go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc"
+	"go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
 	"go.opentelemetry.io/otel"
 	"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc"
 	"go.opentelemetry.io/otel/propagation"
@@ -333,14 +337,24 @@ func (cs *checkoutService) chargeCard(ctx context.Context, amount *pb.Money, pay
 }
 
 func (cs *checkoutService) sendOrderConfirmation(ctx context.Context, email string, order *pb.OrderResult) error {
-	conn, err := createClient(ctx, cs.emailSvcAddr)
+	emailServicePayload, err := json.Marshal(map[string]interface{}{
+		"email": email,
+		"order": order,
+	})
 	if err != nil {
-		return fmt.Errorf("failed to connect email service: %+v", err)
+		return fmt.Errorf("failed to marshal order to JSON: %+v", err)
 	}
-	defer conn.Close()
-	_, err = pb.NewEmailServiceClient(conn).SendOrderConfirmation(ctx, &pb.SendOrderConfirmationRequest{
-		Email: email,
-		Order: order})
+
+	resp, err := otelhttp.Post(ctx, cs.emailSvcAddr+"/send_order_confirmation", "application/json", bytes.NewBuffer(emailServicePayload))
+	if err != nil {
+		return fmt.Errorf("failed POST to email service: %+v", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return fmt.Errorf("failed POST to email service: expected 200, got %d", resp.StatusCode)
+	}
+
 	return err
 }
 

src/emailservice/.ruby-version

@@ -0,0 +1 @@
+3.1.2

src/emailservice/Dockerfile

@@ -12,28 +12,14 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-FROM python:3.10-slim
+FROM ruby:3.1.2
 
-# get packages
-COPY requirements.txt .
-RUN pip install -r requirements.txt
-
-# Enable unbuffered logging
-ENV PYTHONUNBUFFERED=1
-
-RUN apt-get -qq update \
-    && apt-get install -y --no-install-recommends \
-    wget
-
-# Download the grpc health probe
-RUN GRPC_HEALTH_PROBE_VERSION=v0.4.7 && \
-    wget -qO/bin/grpc_health_probe https://github.com/grpc-ecosystem/grpc-health-probe/releases/download/${GRPC_HEALTH_PROBE_VERSION}/grpc_health_probe-linux-amd64 && \
-    chmod +x /bin/grpc_health_probe
+COPY Gemfile* .
+RUN bundle install
 
 WORKDIR /email_server
 
-# Add the application
 COPY . .
 
 EXPOSE 8080
-ENTRYPOINT [ "opentelemetry-instrument", "python", "email_server.py" ]
+ENTRYPOINT ["bundle", "exec", "ruby", "email_server.rb"]

src/emailservice/Gemfile

@@ -0,0 +1,10 @@
+source "https://rubygems.org"
+
+gem "net-smtp", "~> 0.3"
+gem "pony",     "~> 1.13"
+gem "puma",     "~> 5.6"
+gem "sinatra",  "~> 2.2"
+
+gem "opentelemetry-sdk",                     "~> 1.1"
+gem "opentelemetry-exporter-otlp",           "~> 0.21"
+gem "opentelemetry-instrumentation-sinatra", "~> 0.19"

src/emailservice/Gemfile.lock

@@ -0,0 +1,74 @@
+GEM
+  remote: https://rubygems.org/
+  specs:
+    digest (3.1.0)
+    google-protobuf (3.21.1)
+    googleapis-common-protos-types (1.3.1)
+      google-protobuf (~> 3.14)
+    mail (2.7.1)
+      mini_mime (>= 0.1.1)
+    mini_mime (1.1.2)
+    mustermann (1.1.1)
+      ruby2_keywords (~> 0.0.1)
+    net-protocol (0.1.3)
+      timeout
+    net-smtp (0.3.1)
+      digest
+      net-protocol
+      timeout
+    nio4r (2.5.8)
+    opentelemetry-api (1.0.2)
+    opentelemetry-common (0.19.6)
+      opentelemetry-api (~> 1.0)
+    opentelemetry-exporter-otlp (0.21.3)
+      google-protobuf (~> 3.19)
+      googleapis-common-protos-types (~> 1.3)
+      opentelemetry-api (~> 1.0)
+      opentelemetry-common (~> 0.19.3)
+      opentelemetry-sdk (~> 1.0)
+      opentelemetry-semantic_conventions
+    opentelemetry-instrumentation-base (0.20.0)
+      opentelemetry-api (~> 1.0)
+    opentelemetry-instrumentation-sinatra (0.19.4)
+      opentelemetry-api (~> 1.0)
+      opentelemetry-common (~> 0.19.3)
+      opentelemetry-instrumentation-base (~> 0.20.0)
+    opentelemetry-registry (0.1.0)
+      opentelemetry-api (~> 1.0.1)
+    opentelemetry-sdk (1.1.0)
+      opentelemetry-api (~> 1.0)
+      opentelemetry-common (~> 0.19.3)
+      opentelemetry-registry (~> 0.1)
+      opentelemetry-semantic_conventions
+    opentelemetry-semantic_conventions (1.8.0)
+      opentelemetry-api (~> 1.0)
+    pony (1.13.1)
+      mail (>= 2.0)
+    puma (5.6.4)
+      nio4r (~> 2.0)
+    rack (2.2.3.1)
+    rack-protection (2.2.0)
+      rack
+    ruby2_keywords (0.0.5)
+    sinatra (2.2.0)
+      mustermann (~> 1.0)
+      rack (~> 2.2)
+      rack-protection (= 2.2.0)
+      tilt (~> 2.0)
+    tilt (2.0.10)
+    timeout (0.3.0)
+
+PLATFORMS
+  arm64-darwin-21
+
+DEPENDENCIES
+  net-smtp (~> 0.3)
+  opentelemetry-exporter-otlp (~> 0.21)
+  opentelemetry-instrumentation-sinatra (~> 0.19)
+  opentelemetry-sdk (~> 1.1)
+  pony (~> 1.13)
+  puma (~> 5.6)
+  sinatra (~> 2.2)
+
+BUNDLED WITH
+   2.3.7

src/emailservice/README.md

@@ -1,3 +1,23 @@
-# Read Me
+# Email Service
 
-This is a placeholder
+The Email service "sends" an email to the customer with their order details by
+rendering it as a log message. It expects a JSON payload like:
+
+```json
+{
+  "email": "[email protected]",
+  "order": "<serialized order protobuf>"
+}
+```
+
+## Building locally
+
+We use `bundler` to manage dependencies. To get started, simply `bundle install`.
+
+## Running locally
+
+You may run this service locally with `bundle exec ruby email_server.rb`.
+
+## Building docker image
+
+From `src/emailservice`, run `docker build .`