fix for require('fs') in compositions

Fixes #934

Author: starpit

app/plugins/modules/composer/lib/create-from-source.js

@@ -113,9 +113,10 @@ exports.compileToFSM = (src, opts={}) => new Promise((resolve, reject) => {
                             require: m => {
                                 if (m === '@ibm-functions/composer') {
                                     return openwhiskComposer
+                                } else if (m.charAt(0) !== '.') {
+                                    return require(m)
                                 } else {
-                                    return require(path.resolve(dir, m))
-                                    
+                                    return require(path.resolve(m))
                                 }
                             }
                         }
@@ -134,7 +135,20 @@ exports.compileToFSM = (src, opts={}) => new Promise((resolve, reject) => {
                         }
                         const sandboxWithComposer = Object.assign(sandbox, { composer: openwhiskComposer })
 
-                        let res = vm.runInNewContext(code, sandboxWithComposer)
+                        // we need to be in the directory of the
+                        // source, in case it does relative requires
+                        // or reads from that relative location
+                        const curdir = process.cwd()
+                        process.chdir(ui.findFile(dir))
+
+                        let res
+                        try {
+                            res = vm.runInNewContext(code, sandboxWithComposer)
+                        } finally {
+                            // make sure we change back to where we started
+                            process.chdir(curdir)
+                        }
+
                         debug('res', typeof res, res)
 
                         if (typeof res === 'function') {

tests/data/composer-source/author-map.json

@@ -0,0 +1,3 @@
+{
+    "hello": "world"
+}

tests/data/composer-source/echo.js

@@ -0,0 +1 @@
+module.exports = n => `echo${n}`

tests/data/composer-source/fs-read.js

@@ -0,0 +1,8 @@
+function foo() {
+    const fs = require('fs');
+    const authorMap = JSON.parse(fs.readFileSync('author-map.json', 'utf8'));
+    return composer.let({ am: authorMap }, p => {
+        return am[p.author] == undefined ? {} : am[p.author]
+    })
+}
+composer.sequence(foo())

tests/data/composer-source/require-absolute.js

@@ -0,0 +1,2 @@
+require('fs')
+composer.sequence('echo1','echo2')

tests/data/composer-source/require-relative.js

@@ -0,0 +1,2 @@
+composer.sequence(require('./echo')(1),
+                  require('./echo')(2))

tests/tests/passes/07/composer-create.js

@@ -318,7 +318,8 @@ describe('app create and sessions', function() {
     fs.readdirSync(srcDir).forEach((file,idx) => {
         const name = `${seqName2}-${idx}`
 
-        if (file.endsWith('.js')) {
+        // echo.js is used by require-relative.js, it isn't a composition on its own
+        if (file.endsWith('.js') && file !== 'echo.js') {
             it(`should create a composer sequence from source ${file}`, () => cli.do(`app create ${name} ${path.join(srcDir, file)}`, this.app)
 	        .then(cli.expectOK)
                .then(sidecar.expectOpen)

tests/tests/passes/07/composer-viz.js

@@ -47,6 +47,9 @@ const fsm = input('fsm.json'), fsmStruct = JSON.parse(fs.readFileSync(fsm.path).
       demo = composerInput('demo.js'),
       demoRetain = composerInput('demo-retain.js'),
       mask = composerInput('mask.js'),
+      requireAbsolute = composerInput('require-absolute.js'),
+      requireRelative = composerInput('require-relative.js'),
+      fsRead = composerInput('fs-read.js'),
       addSubscription = composerErrorInput('addSubscription.js')
 
 /**
@@ -237,6 +240,27 @@ describe('show the composer visualization without creating openwhisk assets', fu
        .then(verifyEdgeExists('echo1', 'echo2'))
        .catch(common.oops(this)))
 
+    /** test: from the openwhisk-composer/samples directory */
+    it(`show visualization from javascript source ${requireAbsolute.path}`, () => cli.do(`app viz ${requireAbsolute.path}`, this.app)
+       .then(verifyTheBasicStuff(requireAbsolute.file, 'composerLib'))
+       .then(verifyNodeExists('echo1'))
+       .then(verifyNodeExists('echo2'))
+       .then(verifyEdgeExists('echo1', 'echo2'))
+       .catch(common.oops(this)))
+
+    /** test: from the openwhisk-composer/samples directory */
+    it(`show visualization from javascript source ${requireRelative.path}`, () => cli.do(`app viz ${requireRelative.path}`, this.app)
+       .then(verifyTheBasicStuff(requireRelative.file, 'composerLib'))
+       .then(verifyNodeExists('echo1'))
+       .then(verifyNodeExists('echo2'))
+       .then(verifyEdgeExists('echo1', 'echo2'))
+       .catch(common.oops(this)))
+
+    /** test: from the openwhisk-composer/samples directory */
+    it(`show visualization from javascript source ${fsRead.path}`, () => cli.do(`app viz ${fsRead.path}`, this.app)
+       .then(verifyTheBasicStuff(fsRead.file, 'composerLib'))
+       .catch(common.oops(this)))
+
     it(`fail to show visualization for addSubscription without -e for env var assignment`, () => cli.do(`preview ${addSubscription.path}`, this.app)
        .then(cli.expectError(0, 'SLACK_TOKEN required in environment'))
        .catch(common.oops(this)))