Introduce header argument

src/index.js

@@ -39,6 +39,8 @@ function printHelp(console) {
                            create (if the file does not exist)
     --require <module>     If importing the schema from a module, require the specified
                            module first (useful for e.g. babel-register)
+    --header <name=value>  Additional header(s) to use in GraphQL request
+                           e.g. --header "Authorization=Bearer ey..."
     --version              Print version and exit
 `)
 }
@@ -63,7 +65,13 @@ function run(
       }
     }
     const schemaPath = args._[0]
-    loadSchemaJSON(schemaPath).then(schema => {
+    const headers = [].concat(args['header'] || []).reduce((obj, header) => {
+      const [key, ...value] = String(header).split('=')
+      obj[key] = value.join('=')
+      return obj
+    }, {})
+    const loadOptions = { headers }
+    loadSchemaJSON(schemaPath, loadOptions).then(schema => {
       const options = {
         title: args.title,
         skipTitle: false,

src/loadSchemaJSON.js

@@ -32,7 +32,8 @@ function fetchSchemaJSON(url, options) {
     method: 'POST',
     headers: {
       Accept: 'application/json',
-      'Content-Type': 'application/json'
+      'Content-Type': 'application/json',
+      ...options.headers
     },
     body: JSON.stringify({ query: graphql.introspectionQuery })
   })
@@ -90,9 +91,9 @@ async function requireSchema(schemaPath) {
   )
 }
 
-function loadSchemaJSON(schemaPath) {
+function loadSchemaJSON(schemaPath, loadOptions) {
   if (schemaPath.indexOf('://') >= 0) {
-    return fetchSchemaJSON(schemaPath)
+    return fetchSchemaJSON(schemaPath, loadOptions)
   } else if (schemaPath.match(/\.g(raph)?ql$/)) {
     return parseSchemaGraphQL(schemaPath).then(schemaToJSON)
   }

test/__snapshots__/index.test.js.snap

@@ -477,6 +477,8 @@ Object {
                            create (if the file does not exist)
     --require <module>     If importing the schema from a module, require the specified
                            module first (useful for e.g. babel-register)
+    --header <name=value>  Additional header(s) to use in GraphQL request
+                           e.g. --header \\"Authorization=Bearer ey...\\"
     --version              Print version and exit
 
 ",
@@ -510,6 +512,8 @@ Object {
                            create (if the file does not exist)
     --require <module>     If importing the schema from a module, require the specified
                            module first (useful for e.g. babel-register)
+    --header <name=value>  Additional header(s) to use in GraphQL request
+                           e.g. --header \\"Authorization=Bearer ey...\\"
     --version              Print version and exit
 
 ",

test/index.test.js

@@ -1,13 +1,17 @@
 const fs = require('fs')
 const path = require('path')
 const tempy = require('tempy')
+const resolveFrom = require('resolve-from')
 const {
   run,
   loadSchemaJSON,
   renderSchema,
   updateSchema
 } = require('../src/index')
 
+jest.mock('node-fetch')
+const fetch = require('node-fetch')
+
 function createPrinter() {
   const printer = chunk => {
     printer.output += `${chunk}\n`
@@ -84,6 +88,24 @@ describe('loadSchemaJSON()', () => {
     )
     expect(graphqlFileSchema.__schema.queryType.name).toBe('Query')
   })
+
+  it('can call fetch with correct parameters', async () => {
+    fetch.mockImplementation(() =>
+      Promise.resolve({
+        json: () => resolveFrom('.', 'graphbrainz/schema.json')
+      })
+    )
+
+    await loadSchemaJSON('http://example.com', {
+      headers: { key1: 'value1' }
+    })
+    expect(fetch.mock.calls[0][0]).toBe('http://example.com')
+    expect(fetch.mock.calls[0][1].headers).toEqual({
+      Accept: 'application/json',
+      'Content-Type': 'application/json',
+      key1: 'value1'
+    })
+  })
 })
 
 describe('updateSchema()', () => {