Validating and Viewing OpenAPI Definitions with Docker

- Quality Assurance, Programming

Assembled cog wheels

Here are a few commands I crafted to validate and easily read API definitions in the OpenAPI format, using Docker and open source tools provided by Swagger. I have yet to convert them into proper shell scripts, but I hope these will be helpful nonetheless.

The commands are designed to be run in a Linux shell, including under Windows Subsystem for Linux. Also, the OpenAPI definition will be assumed to be named openapi.json or openapi.yaml, depending on the file format used, and be located in the current directory the commands are to be executed.

Before doing any of the following, make sure to install Docker, and to start the service using the following command:

sudo service docker start


First, download the Swagger Badge Validator microservice image:

docker pull swaggerapi/swagger-validator-v2

Next, start the microservice; this will use port 8080 on your machine:

docker run --detach --name swagger-validator-v2 --publish 8080:8080 swaggerapi/swagger-validator-v2

You are now ready to send a request to the microservice to validate it.

JSON case:

curl --request POST http://localhost:8080/validator/debug --header "Accept: application/json" --header "Content-Type: application/json" --data-binary @openapi.json

YAML case:

curl --request POST http://localhost:8080/validator/debug --header "Accept: application/json" --header "Content-Type: application/yaml" --data-binary @openapi.yaml

This will return a JSON object. If the object is empty, the validation passed, otherwise it will contain a list of errors.

Once you're done, you may stop and remove the microservice:

docker stop swagger-validator-v2
docker rm swagger-validator-v2


First, download the Swagger UI microservice image:

docker pull swaggerapi/swagger-ui

Next, start the microservice; this will use port 80 on your machine.

JSON case:

docker run --detach --env SWAGGER_JSON=/ext/openapi.json --mount type=bind,src=$PWD,dst=/ext --name swagger-ui --publish 80:8080 swaggerapi/swagger-ui

YAML case:

docker run --detach --env SWAGGER_JSON=/ext/openapi.yaml --mount type=bind,src=$PWD,dst=/ext --name swagger-ui --publish 80:8080 swaggerapi/swagger-ui

You may now read the OpenAPI definition in Swagger UI by opening the following URL:


Once you're done, you may stop and remove the microservice:

docker stop swagger-ui
docker rm swagger-ui

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