Service Functioning

This repository is a fork of the open source krakend API gateway. It is used in Unacademy for the following use cases

1. Routing requests transparently to multiple upstream microservices and act as a single entrypoint for our services. The routing config can be viewed in krakend-config repo.
2. Validating the auth token passed in the request to offload authentication from upstream services.

Local Setup

Install gvm (go version manager) to setup go virtual env, if you already have a virtual env, you can use that as well

steps to install gvm and use activate go virtual env

1. install gvm - bash < <(curl -s -S -L https://raw.githubusercontent.com/moovweb/gvm/master/binscripts/gvm-installer)
2. install go1.16 version gvm install go1.17
3. use the installed go version gvm use go1.17

Setup and build krakend-ce

1. Install dependencies - go get .
2. build binary -

     go build \
   -ldflags="-X github.com/devopsfaith/krakend/core.KrakendVersion=1.4.2 \
   -X github.com/devopsfaith/krakend/core.KrakendHeaderName=X-Gateway \
   -X github.com/devopsfaith/krakend/transport/http/server.CompleteResponseHeaderName=X-Gateway-Completed" \
   -o krakend ./cmd/krakend-ce
   

3. install runtime plugins
   • clone krakend-plugins repository and cd into the directory
   • build plugins in plugin mode using - make all
   • copy plugins into the plugins directory mkdir plugins && cp <krakend-plugins-dir>/bin/*.so plugins/
4. copy config as per your requirement, to get gamma config, you can copy it from the krakend gamma pipeline, or if you want to test, you can use examples/simple_config.json to tet.
5. copy the env variables from gamma vault and export that variables in your terminal. Comment out variables FC_ENABLE FC_OUT FC_PARTIALS FC_SETTINGS FC_TEMPLATES since you are directly copying the completely built config.
6. run ./krakend run -c <path-to-config-file>
7. if you want to setup debugger in vscode, I have attached launch.json file, you can directly run the debugger directly using that, you would have to just update the env key from env from vault.

Docker setup

You can use the following Dockerfile to setup docker container for krakend. Prequisites

• Docker engine
• AWS prod account configs
• ECR Access for your IAM role

FROM 838337956332.dkr.ecr.ap-southeast-1.amazonaws.com/dockerhub:golang_1.17.6

ARG github_token
RUN git config --global url."https://${github_token}@github.com/".insteadOf "https://github.com/"
ENV github_token ""

WORKDIR /krakend

COPY . .
RUN go get .; go build \
  -ldflags="-X github.com/devopsfaith/krakend/core.KrakendVersion=1.4.2 \
  -X github.com/devopsfaith/krakend/core.KrakendHeaderName=X-Gateway \
  -X github.com/devopsfaith/krakend/transport/http/server.CompleteResponseHeaderName=X-Gateway-Completed" \
  -o krakend ./cmd/krakend-ce

# pull krakend-plugins repository
ARG KRAKEND_PLUGINS_BRANCH
RUN git clone https://github.com/Unacademy/krakend-plugins.git -b $KRAKEND_PLUGINS_BRANCH
RUN cd krakend-plugins; make all
RUN mkdir plugins; cp krakend-plugins/bin/*.so plugins/

# copy krakend config files

EXPOSE 8080

ENTRYPOINT [".", ".env.sh"]

CMD ./krakend run -c <config-file-path>

Prod Deployment

To deploy to production, merge your changes in the master branch, and then trigger the following jenkins pipeline

Metrics to Monitor

Krakend is attached as a target group in the main Unacademy API load balancer, so to view the metrics for krakend, you need to view the metrics for the krakend tg i.e k8s-krakend-tg

Alarms

1. 5xx High, threshold 350 in 5mins

Metrics You should monitor the following metrics in the ApplicationELB, Per AppELB, per TG Metrics namespace, link

1. RequestCount
2. HTTPCode_Target_4XX_Count
3. HTTPCode_Target_2XX_Count
4. TargetResponseTime
5. HTTPCode_Target_5XX_Count

Debugging

To debug the service in production, you can view the logs for your service on Opensearch in the index pattern p-krakend-20*

Contact Information

Sagar Yadav
Khyati