BREAKING: Generate output to a single file

README.md

@@ -83,17 +83,15 @@ import * as swaggerUi from 'swagger-ui-express'
 import { prefix } from 'typera-openapi'
 
 import myRoutes from './my-routes'
-import myRouteDefs from './my-routes.openapi'
+import openapi from './openapi'
 
 const openapiDoc: OpenAPIV3.Document = {
   openapi: '3.0.0',
   info: {
     title: 'My cool API',
     version: '0.1.0',
   },
-  paths: {
-    ...prefix('/api', myRouteDefs.paths),
-  },
+  ...openapi,
 }
 
 const app = express()
@@ -102,9 +100,6 @@ app.use('/api-docs', swaggerUi.serve, swaggerUi.setup(openapiDoc))
 app.listen(3000)
 ```
 
-The `prefix` function is used to move OpenAPI path definitions to a different
-prefix, because the `myRoutes` are served from the `/api` prefix.
-
 ## CLI
 
 ```

src/cli.ts

@@ -1,11 +1,9 @@
-#!/usr/bin/env node
 import * as fs from 'fs'
 import * as path from 'path'
-import { OpenAPIV3 } from 'openapi-types'
 import * as ts from 'typescript'
 import * as yargs from 'yargs'
 
-import { generate } from '.'
+import { GenerateResult, generate } from '.'
 import { Logger } from './context'
 import { runPrettier } from './prettify'
 
@@ -22,37 +20,39 @@ const parseArgs = () =>
       type: 'boolean',
       default: false,
     })
-    .option('format', {
-      description: 'Output file format',
-      choices: ['ts' as const, 'json' as const],
-      default: 'ts' as Format,
+    .option('outfile', {
+      alias: 'o',
+      description: 'Output file. Must end in `.ts` or `.json`.',
+      default: 'openapi.ts',
+      coerce: (arg: string): [string, Format] => {
+        if (arg.endsWith('.ts')) return [arg, 'ts']
+        if (arg.endsWith('.json')) return [arg, 'json']
+        throw new Error('outfile must end in `.ts` or `.json`')
+      },
     })
     .option('tsconfig', {
       description: 'Which tsconfig.json to use',
       default: 'tsconfig.json',
     })
     .option('prettify', {
       alias: 'p',
-      description: 'Apply prettier to output files',
+      description: 'Apply prettier to the output file',
       type: 'boolean',
       default: false,
     })
     .option('check', {
       alias: 'c',
       description:
-        'Exit with an error if output files are not up-to-date (useful for CI)',
+        'Exit with an error if the output file is not up-to-date (useful for CI)',
       type: 'boolean',
       default: false,
     }).argv
 
-const outputFileName = (sourceFileName: string, ext: string): string =>
-  sourceFileName.slice(0, -path.extname(sourceFileName).length) + ext
-
-const main = async () => {
+const main = async (): Promise<number> => {
   const args = parseArgs()
 
   const sourceFiles = args._.map((x) => path.resolve(x.toString()))
-  const ext = `.openapi.${args.format}`
+  const [outfile, format] = args.outfile
 
   const compilerOptions = readCompilerOptions(args.tsconfig)
   if (!compilerOptions) process.exit(1)
@@ -61,32 +61,18 @@ const main = async () => {
     console.log(`Compiler options: ${JSON.stringify(compilerOptions, null, 2)}`)
   }
 
-  const results = generate(sourceFiles, compilerOptions, {
-    log,
-  }).map((result) => ({
-    ...result,
-    outputFileName: outputFileName(result.fileName, ext),
-  }))
-
-  let success = true
-  for (const { outputFileName, paths, components } of results) {
-    let content =
-      args.format === 'ts'
-        ? tsString(paths, components)
-        : jsonString(paths, components)
-    if (args.prettify) {
-      content = await runPrettier(outputFileName, content)
-    }
-    if (args.check) {
-      if (!checkOutput(outputFileName, content)) success = false
-    } else {
-      writeOutput(outputFileName, content)
-    }
+  const result = generate(sourceFiles, compilerOptions, { log })
+  let content = format === 'ts' ? tsString(result) : jsonString(result)
+  if (args.prettify) {
+    content = await runPrettier(outfile, content)
   }
-
-  if (!success) {
-    process.exit(1)
+  if (args.check) {
+    if (!checkOutput(outfile, content)) return 1
+  } else {
+    writeOutput(outfile, content)
   }
+
+  return 0
 }
 
 const readCompilerOptions = (
@@ -136,22 +122,18 @@ const writeOutput = (fileName: string, content: string): void => {
   fs.writeFileSync(fileName, content)
 }
 
-const tsString = (
-  paths: OpenAPIV3.PathsObject,
-  components: OpenAPIV3.ComponentsObject
-): string => `\
+const tsString = (result: GenerateResult): string => `\
 import { OpenAPIV3 } from 'openapi-types'
 
 const spec: { paths: OpenAPIV3.PathsObject, components: OpenAPIV3.ComponentsObject } = ${JSON.stringify(
-  { paths, components }
+  result
 )};
 
 export default spec;
 `
 
-const jsonString = (
-  paths: OpenAPIV3.PathsObject,
-  components: OpenAPIV3.ComponentsObject
-): string => JSON.stringify({ paths, components })
+const jsonString = (result: GenerateResult): string => JSON.stringify(result)
 
-main()
+main().then((status) => {
+  if (status !== 0) process.exit(status)
+})

src/generate.ts

@@ -27,8 +27,7 @@ interface GenerateOptions {
   log: Logger
 }
 
-interface Result {
-  fileName: string
+export interface GenerateResult {
   paths: OpenAPIV3.PathsObject
   components: OpenAPIV3.ComponentsObject
 }
@@ -37,35 +36,32 @@ export const generate = (
   fileNames: string[],
   compilerOptions: ts.CompilerOptions,
   options?: GenerateOptions
-): Result[] => {
+): GenerateResult => {
   const log = options?.log || (() => undefined)
   const program = ts.createProgram(fileNames, compilerOptions)
   const checker = program.getTypeChecker()
 
-  const result: Result[] = []
+  const components = new Components()
+  let paths: OpenAPIV3.PathsObject = {}
 
   for (const sourceFile of program.getSourceFiles()) {
     if (!fileNames.includes(sourceFile.fileName)) continue
     if (sourceFile.isDeclarationFile) continue
 
     ts.forEachChild(sourceFile, (node) => {
-      const components = new Components()
-      const paths = visitTopLevelNode(
+      const newPaths = visitTopLevelNode(
         context(checker, sourceFile, log, node),
         components,
         node
       )
-      if (paths) {
-        result.push({
-          fileName: sourceFile.fileName,
-          paths,
-          components: components.build(),
-        })
+      if (newPaths) {
+        // TODO: What if a route is defined multiple times?
+        paths = { ...paths, ...newPaths }
       }
     })
   }
 
-  return result
+  return { paths, components: components.build() }
 }
 
 const visitTopLevelNode = (

src/index.ts

@@ -1,4 +1,4 @@
-export { generate } from './generate'
+export { GenerateResult, generate } from './generate'
 export { LogLevel } from './context'
 import { OpenAPIV3 } from 'openapi-types'