Gatsby source plugin for pulling data into Gatsby from Open API/Swagger specifications

• Sample

Features

• Pulls Open API/Swagger JSON specifications from various sources, these can be local files or from HTTP services or any custom function which resolves a JSON spec
• Supports multiple specs, so useful for aggregating numerous services where the specs are co-located with each service
• Document your APIs using React!

What's missing

This is work in progress, currently:

• No support for YAML
• Only supports Swagger version 2.0 JSON
• Various Swagger properties are not converted to fields on nodes, only the main properties (general information, paths, responses, and definitions), create an issue or PR

Install

npm install gatsby-source-openapi-aggregate --save

Configuring plugin

// gatsby-config.js

plugins: [
  {
    resolve: `gatsby-source-openapi-aggregate`,
    options: {
      specs: [                // specs collection is required, you can define as many specs as you want
        {
          name: 'myspec',     // required, must be unique
          resolve: () => ...  // required, function which returns a Promise resolving Swagger JSON
        }
      ]
    }
  }
]

Example resolve functions

Retrieving Swagger document from local file:

const fs = require('fs')
const path = require('path')

const fromJson = filePath => {
  return new Promise((resolve, reject) => {
    fs.readFile(filePath, 'utf8', (err, data) => {
      if (err) {
        reject(err)
        return
      }

      resolve(data)
    })
  })
}

...

  plugins: [
    {
      resolve: `gatsby-source-openapi-aggregate`,
      options: {
        specs: [
          {
            name: 'myspec',
            resolve: () => fromJson(path.resolve(__dirname, './swagger.json'))
          }
        ]
      }
    },

Retrieving Swagger document from HTTP request:

const fetchSpec = async url => {
  return fetch(url).then(response => {
    if (response.status === 200) {
      return response.text()
    }

    throw new Error('There was an error retrieving document.')
  })
}

How to query

The plugin adds the following collections:

• allOpenApiSpec
• allOpenApiSpecPath
• allOpenApiSpecResponse
• allOpenApiSpecDefinition

You can inspect these in GraphiQL at http://localhost:8000/___graphql

For example, to retrieve a list of spec names and titles ready for display:

// src/pages/index.js

export const query = graphql`
  query IndexQuery {
    allOpenApiSpec {
      edges {
        node {
          name
          title
        }
      }
    }
    ...

To create a detail page for each spec:

// gatsby-node.js

exports.createPages = ({ graphql, boundActionCreators }) => {
  const { createPage } = boundActionCreators
  return new Promise((resolve, reject) => {
    graphql(`
      {
        allOpenApiSpec {
          edges {
            node {
              id
              name
            }
          }
        }
      }
    `).then(result => {
      result.data.allOpenApiSpec.edges.map(({ node }) => {
        createPage({
          path: `apis/${node.name}`,
          component: path.resolve(`./src/templates/api.js`),
          context: {
            id: node.id,
          },
        })
      })

      resolve()
    })
  })
}

The above creates a new page for every spec defined in the plugin options, using /apis/<name> as the path, where <name> is the name you defined within the plugin options.

Each page uses the ./src/templates/api.js React component to render the detail page. The node.id is passed to the context so that it is available as a GraphQL variable so that we can retreive the appropriate spec node from the api.js component.

// api.js

export const query = graphql`
  query ApiQuery($id: String!) {
    openApiSpec(id: { eq: $id }) {
      version
      title
      description
      childrenOpenApiSpecPath {
        name
        verb
        summary
        description
        parameters {
          name
          in
          description
          required
          type
          format
        }
        tag
        childrenOpenApiSpecResponse {
          id
          statusCode
          description
          childrenOpenApiSpecDefinition {
            name
            properties {
              name
              type
              description
              format
            }
          }
        }
      }
    }
  }
`

In the above example, we're using the $id variable to retrieve the appropriate spec for that page. We're retreiving basic spec information (such as version, title, description) as well as the children paths for the spec, their associated properties, as well as each paths child responses and in turn their child definitions.

Each path has a tags and tag field - tags is the original array of tags associated with the path. The tag field is a convenience comma separated string of all tags. If you wish to display paths by tag (like Swagger UI), then you can group on this tag field. See the full sample for details.