Add tests for redirect rewrites.

Author: rabbah

src/index.js

@@ -2,10 +2,10 @@ const {existsSync} = require('fs')
 const {appendFile, readFile, readdir, writeFile} = require('fs').promises
 const {join} = require('path')
 const {homedir, tmpdir} = require('os')
-
 const toml = require('@iarna/toml')
 const cpx = require('cpx')
 const build = require('netlify-lambda/lib/build')
+const {parseRedirectsFormat} = require('netlify-redirect-parser')
 
 const functionsBuildDir = `functions-build-${Date.now()}`
 const nimConfig = join(homedir(), '.nimbella')
@@ -188,12 +188,26 @@ module.exports = {
     )
     apihost = apihost.replace(/^(https:\/\/)/, '')
 
+    // Creates or updates the _redirects file; this file takes precedence
+    // over other redirect declarations, and is processed from top to bottom
+    //
+    // First: if we deployed netlify functions to nimbella, scan the redirects
+    // for matching rewrites with /.netlify/functions/* as their target
+    // and remap them to their nimbella api end points.
+    //
+    // Second: if there is an API path directive input.api, add a matching rule
+    // to the _redirects file. The target is either the Nimbella namespace/:splat
+    // or namespace/default/:splat. The latter is used when deploying Netlify functions
+    // to Nimbella.
+    //
+    // The first set of rewrites is pre-pended to the _redirects file, then the second
+    // set, if any.
+
     if (isActions) {
       if (existsSync(redirectsFile)) {
         console.log(
           "Found _redirects file. We will rewrite rules that redirect (200 rewrites) to '/.netlify/functions/*'."
         )
-        const {parseRedirectsFormat} = require('netlify-redirect-parser')
         const {success} = await parseRedirectsFormat(redirectsFile)
         redirects.push(...success)
       }
@@ -213,7 +227,9 @@ module.exports = {
         ) {
           const redirectPath = redirect.to.split('/.netlify/functions/')[1]
           redirectRules.push(
-            `${redirect.from} https://${apihost}/api/v1/web/${namespace}/default/${redirectPath} 200!`
+            `${
+              redirect.from || redirect.path
+            } https://${apihost}/api/v1/web/${namespace}/default/${redirectPath} 200!`
           )
         }
       }
@@ -237,12 +253,17 @@ module.exports = {
     }
 
     if (redirectRules.length > 0) {
-      if (!existsSync(constants.PUBLISH_DIR)) {
+      let content = ''
+      if (existsSync(redirectsFile)) {
+        content = await readFile(redirectsFile)
+      } else if (!existsSync(constants.PUBLISH_DIR)) {
         const mkdir = require('make-dir')
         await mkdir(constants.PUBLISH_DIR)
       }
 
-      await appendFile(redirectsFile, redirectRules.join('\n'))
+      // The rewrites take precedence
+      await writeFile(redirectsFile, redirectRules.join('\n') + '\n')
+      await appendFile(redirectsFile, content)
     }
   }
 }

test/index.js

@@ -229,34 +229,113 @@ describe('onPostBuild()', () => {
       utils,
       constants: {CONFIG_PATH: 'netlify.toml', PUBLISH_DIR: ''},
       inputs: {
-        path: '',
+        path: '/api',
         functions: 'some-dir'
       }
     }
 
     mockFs({
       'netlify.toml': `
         [[redirects]]
-        from = "/*"
+        from = "/home"
         to = "/index.html"
         status = 200
-        `,
+
+        [[redirects]]
+        from = "/somefn"
+        to = "/.netlify/functions/fn"
+        status = 200
+      `,
       'some-dir': {
         'create.js': '',
         'update.js': ''
       }
     })
+
     await plugin.onPreBuild(pluginInputs)
     await plugin.onPostBuild(pluginInputs)
-    const redirects = String(fs.readFileSync('_redirects'))
+    const redirects = String(fs.readFileSync('_redirects')).trim().split('\n')
     mockFs.restore()
 
     expect(console.log.mock.calls[1][0]).toEqual(
       "Found redirect rules in netlify.toml. We will rewrite rules that redirect (200 rewrites) to '/.netlify/functions/*'."
     )
 
-    expect(redirects).toEqual(
-      '/* https://somehost/api/v1/web/namespace/default/:splat 200!'
+    expect(redirects.length).toEqual(2)
+    expect(redirects[0]).toEqual(
+      '/somefn https://somehost/api/v1/web/namespace/default/fn 200!'
+    )
+    expect(redirects[1]).toEqual(
+      '/api/* https://somehost/api/v1/web/namespace/default/:splat 200!'
     )
   })
+
+  test('should rewrite existing redirects to .netlify/functions/ in netlify.toml or _redirects if functions are used', async () => {
+    process.env.NIMBELLA_LOGIN_TOKEN = 'somevalue'
+    process.env.CONTEXT = 'production'
+    utils.run.command = jest.fn((cmd) => {
+      if (cmd === 'nim auth current') return {stdout: 'namespace'}
+      if (cmd === 'nim auth current --apihost') return {stdout: 'somehost'}
+      return {stdout: '???'}
+    })
+
+    const pluginInputs = {
+      utils,
+      constants: {CONFIG_PATH: 'netlify.toml', PUBLISH_DIR: ''},
+      inputs: {
+        path: '/api',
+        functions: 'some-dir'
+      }
+    }
+
+    mockFs({
+      'netlify.toml': `
+        [[redirects]]
+        from = "/home"
+        to = "/index.html"
+        status = 200
+
+        [[redirects]]
+        from = "/somefn"
+        to = "/.netlify/functions/fn1"
+        status = 200
+      `,
+      'some-dir': {
+        'create.js': '',
+        'update.js': ''
+      },
+      _redirects: [
+        '/mypath https://example.com',
+        '/fn2 /.netlify/functions/fn2 200'
+      ].join('\n')
+    })
+
+    await plugin.onPreBuild(pluginInputs)
+    await plugin.onPostBuild(pluginInputs)
+    const redirects = String(fs.readFileSync('_redirects'))
+      .split('\n')
+      .filter((_) => _)
+    mockFs.restore()
+
+    expect(console.log.mock.calls[1][0]).toEqual(
+      "Found _redirects file. We will rewrite rules that redirect (200 rewrites) to '/.netlify/functions/*'."
+    )
+
+    expect(console.log.mock.calls[2][0]).toEqual(
+      "Found redirect rules in netlify.toml. We will rewrite rules that redirect (200 rewrites) to '/.netlify/functions/*'."
+    )
+
+    expect(redirects.length).toEqual(5)
+    expect(redirects[0]).toEqual(
+      '/fn2 https://somehost/api/v1/web/namespace/default/fn2 200!'
+    ) // _redirects rewrites is first
+    expect(redirects[1]).toEqual(
+      '/somefn https://somehost/api/v1/web/namespace/default/fn1 200!'
+    ) // Then toml rewrite
+    expect(redirects[2]).toEqual(
+      '/api/* https://somehost/api/v1/web/namespace/default/:splat 200!'
+    ) // And input directive
+    expect(redirects[3]).toEqual('/mypath https://example.com') // Original rewrites come last
+    expect(redirects[4]).toEqual('/fn2 /.netlify/functions/fn2 200') // Original rewrites come last
+  })
 })