Docker Compose

So far, we have four servers running and they can talk to each other as standalone services. In this step, we are going to dockerize all of them and start them with a docker-compose up command.

Before doing that, let’s create two folders under ms_chain for different version of compose files and externalized config files.

cd ~/networknt/light-example-4j/rest/swagger/ms_chain
mkdir compose
mkdir etc

Now in the etc folder, we need to create sub folders for each api and config sub folder

cd ~/networknt/light-example-4j/rest/swagger/ms_chain/etc
mkdir api_a
mkdir api_b
mkdir api_c
mkdir api_d

cd api_a
mkdir config
cd ../api_b
mkdir config
cd ../api_c
mkdir config
cd ../api_d
mkdir config

Let’s create a rest/swagger/ms_chain/compose/docker-compose-app.yml.

#
# docker-compose-app.yml
#

version: '2'

#
# Services
#
services:


    #
    # Microservice: API A
    #
    apia:
        build: ~/networknt/light-example-4j/rest/swagger/ms_chain/api_a/metrics/
        ports:
            - "7441:7441"
        networks:
            - localnet
        volumes:
            - ~/networknt/light-example-4j/rest/swagger/ms_chain/etc/api_a/config:/config

    #
    # Microservice: API B
    #
    apib:
        build: ~/networknt/light-example-4j/rest/swagger/ms_chain/api_b/metrics/
        ports:
            - "7002:7002"
        networks:
            - localnet
        volumes:
            - ~/networknt/light-example-4j/rest/swagger/ms_chain/etc/api_b/config:/config

    #
    # Microservice: API C
    #
    apic:
        build: ~/networknt/light-example-4j/rest/swagger/ms_chain/api_c/metrics/
        ports:
            - "7003:7003"
        networks:
            - localnet
        volumes:
            - ~/networknt/light-example-4j/rest/swagger/ms_chain/etc/api_c/config:/config

    #
    # Microservice: API D
    #
    apid:
        build: ~/networknt/light-example-4j/rest/swagger/ms_chain/api_d/metrics/
        ports:
            - "7004:7004"
        networks:
            - localnet
        volumes:
            - ~/networknt/light-example-4j/rest/swagger/ms_chain/etc/api_d/config:/config

#
# Networks
#
networks:
    localnet:
        external: true
        

From the above docker compose file you can see we have a volume for each api with externalized configuration folder under ms_chain/etc/api_x/config. Since we are using docker compose we cannot use localhost:port to call services and we have to use service name in docker-compose-app.yml for the hostname. To resolve the issue without rebuilding the services we are going to externalize api_a.yml, api_b.yml and api_c.yml to their externalized config folder.

Let’s create api_a.yml in ms_chain/etc/api_a/config folder.

api_b_host: https://apib:7442
api_b_path: /v1/data

Please note that apib is the name of the service in docker-compose-app.yml

Create api_b.yml in ms_chain/etc/api_b/config folder

api_c_host: https://apic:7443
api_c_path: /v1/data

Create api_c.yml in ms_chain/etc/api_c/config folder

api_d_host: https://apid:7444
api_d_path: /v1/data

As each API needs to access OAuth2 server to get access token, so we need to update client.yml to point to the service name in docker-compose instead of localhost.

Now, let’s copy the client.yml from metrics folder for each API into ms_chain/etc/api_x/config folder and update the url for OAuth2 server.

cp ~/networknt/light-example-4j/rest/swagger/ms_chain/api_a/metrics/src/main/resources/config/client.yml ~/networknt/light-example-4j/rest/swagger/ms_chain/etc/api_a/config
cp ~/networknt/light-example-4j/rest/swagger/ms_chain/api_b/metrics/src/main/resources/config/client.yml ~/networknt/light-example-4j/rest/swagger/ms_chain/etc/api_b/config
cp ~/networknt/light-example-4j/rest/swagger/ms_chain/api_c/metrics/src/main/resources/config/client.yml ~/networknt/light-example-4j/rest/swagger/ms_chain/etc/api_c/config

The api_a client.yml in ms_chain/etc/api_a/config folder looks like this after modification. Notice that server host has been changed to oauth2-token and oauth2-key from localhost.

# This is the configuration file for Http2Client.
---
# Settings for TLS
tls:
  # if the server is using self-signed certificate, this need to be false. If true, you have to use CA signed certificate
  # or load truststore that contains the self-signed cretificate.
  verifyHostname: true
  # trust store contains certifictes that server needs. Enable if tls is used.
  loadTrustStore: true
  # trust store location can be specified here or system properties javax.net.ssl.trustStore and password javax.net.ssl.trustStorePassword
  trustStore: tls/client.truststore
  # key store contains client key and it should be loaded if two-way ssl is uesed.
  loadKeyStore: false
  # key store location
  keyStore: tls/client.keystore
# settings for OAuth2 server communication
oauth:
  # OAuth 2.0 token endpoint configuration
  token:
    # The scope token will be renewed automatically 1 minutes before expiry
    tokenRenewBeforeExpired: 60000
    # if scope token is expired, we need short delay so that we can retry faster.
    expiredRefreshRetryDelay: 2000
    # if scope token is not expired but in renew windown, we need slow retry delay.
    earlyRefreshRetryDelay: 4000
    # token server url. The default port number for token service is 6882.
    server_url: https://oauth2-token:6882
    # token service unique id for OAuth 2.0 provider
    serviceId: com.networknt.oauth2-token-1.0.0
    # the following section defines uri and parameters for authorization code grant type
    authorization_code:
      # token endpoint for authorization code grant
      uri: "/oauth2/token"
      # client_id for authorization code grant flow. client_secret is in secret.yml
      client_id: 732bba11-9989-49ae-b26e-a29ed5b3f27e
      # the web server uri that will receive the redirected authorization code
      redirect_uri: https://localhost:8080/authorization_code
      # optional scope, default scope in the client registration will be used if not defined.
      scope:
      - api_b.r
      - api_b.w
    # the following section defines uri and parameters for client credentials grant type
    client_credentials:
      # token endpoint for client credentials grant
      uri: "/oauth2/token"
      # client_id for client credentials grant flow. client_secret is in secret.yml
      client_id: 732bba11-9989-49ae-b26e-a29ed5b3f27e
      # optional scope, default scope in the client registration will be used if not defined.
      scope:
      - api_b.r
      - api_b.w
  # light-oauth2 key distribution endpoint configuration
  key:
    # key distribution server url
    server_url: https://oauth2-key:6886
    # the unique service id for key distribution service
    serviceId: com.networknt.oauth2-key-1.0.0
    # the path for the key distribution endpoint
    uri: "/oauth2/key"
    # client_id used to access key distribution service. It can be the same client_id with token service or not.
    client_id: 732bba11-9989-49ae-b26e-a29ed5b3f27e

Now in order to make the metrics works, we need to copy the metrics.yml to the config folder and modify it for the influxdb hostname.

cp ~/networknt/light-example-4j/rest/swagger/ms_chain/api_a/metrics/src/main/resources/config/metrics.yml ~/networknt/light-example-4j/rest/swagger/ms_chain/etc/api_a/config
cp ~/networknt/light-example-4j/rest/swagger/ms_chain/api_b/metrics/src/main/resources/config/metrics.yml ~/networknt/light-example-4j/rest/swagger/ms_chain/etc/api_b/config
cp ~/networknt/light-example-4j/rest/swagger/ms_chain/api_c/metrics/src/main/resources/config/metrics.yml ~/networknt/light-example-4j/rest/swagger/ms_chain/etc/api_c/config
cp ~/networknt/light-example-4j/rest/swagger/ms_chain/api_d/metrics/src/main/resources/config/metrics.yml ~/networknt/light-example-4j/rest/swagger/ms_chain/etc/api_d/config

The api_a metrics.yml in ms_chain/etc/api_a/config folder looks like this after modification.

# Metrics handler configuration

# If metrics handler is enabled or not
enabled: true

# influxdb protocal can be http, https
influxdbProtocol: http
# influxdb hostname
influxdbHost: influxdb
# influxdb port number
influxdbPort: 8086
# influxdb database name
influxdbName: metrics
# influxdb user
influxdbUser: root
# influx db password
influxdbPass: root
# report and reset metrics in minutes.
reportInMinutes: 1

Now let’s start the docker compose.

cd ~/networknt/light-example-4j/rest/swagger/ms_chain/compose
docker-compose -f docker-compose-app.yml up

Let’s test if the servers are working.

curl -k -H "Authorization: Bearer eyJraWQiOiIxMDAiLCJhbGciOiJSUzI1NiJ9.eyJpc3MiOiJ1cm46Y29tOm5ldHdvcmtudDpvYXV0aDI6djEiLCJhdWQiOiJ1cm46Y29tLm5ldHdvcmtudCIsImV4cCI6MTgwNjIwMDY2MSwianRpIjoibmQtb2ZZbWRIY0JZTUlEYU50MUFudyIsImlhdCI6MTQ5MDg0MDY2MSwibmJmIjoxNDkwODQwNTQxLCJ2ZXJzaW9uIjoiMS4wIiwidXNlcl9pZCI6IlN0ZXZlIiwidXNlcl90eXBlIjoiRU1QTE9ZRUUiLCJjbGllbnRfaWQiOiJmN2Q0MjM0OC1jNjQ3LTRlZmItYTUyZC00YzU3ODc0MjFlNzIiLCJzY29wZSI6WyJhcGlfYS53IiwiYXBpX2IudyIsImFwaV9jLnciLCJhcGlfZC53Iiwic2VydmVyLmluZm8uciJdfQ.SPHICXRY4SuUvWf0NYtwUrQ2-N-NeYT3b4CvxbzNl7D7GL5CF91G3siECrRBVexe0smBHHeiP3bq65rnCVFtwlYYqH6ZS5P7-AFiNcLBzSI9-OhV8JSf5sv381nk2f41IE4av2YUlgY0_mcIDo24ItnuPCxj0l49CAaLb7b1SHZJBQJANJTeQj-wgFsEqwafA-2wH2gehtH8CmOuuYfWO5t5IehP-zJNVT66E4UTRfvvZaJIvNTEQBWPpaZeeK6e56SyBqaLOR7duqJZ8a2UQZRWsDdIVt2Y5jGXQu1gyenIvCQbYLS6iglg6Xaco9emnYFopd2i3psathuX367fvw" https://localhost:7441/v1/data

And we will have the result.

["API D: Message 1","API D: Message 2","API C: Message 1","API C: Message 2","API B: Message 1","API B: Message 2","API A: Message 1","API A: Message 2"]