Merge pull request #445 from embark-framework/features/improve-imports

Improve dapp imports to allow alternate syntax for importing contracts

lib/i18n/locales/en.json

@@ -101,8 +101,17 @@
 	"downloading {{packageName}} {{version}}....": "downloading {{packageName}} {{version}}....",
 	"Swarm node is offline...": "Swarm node is offline...",
 	"Swarm node detected...": "Swarm node detected...",
+	"Cannot find file %s Please ensure you are running this command inside the Dapp folder": "Cannot find file %s Please ensure you are running this command inside the Dapp folder",
+	"finished building": "finished building",
+	"compiling Vyper contracts": "compiling Vyper contracts",
+	"Vyper exited with error code ": "Vyper exited with error code ",
+	"attempted to deploy %s without specifying parameters": "attempted to deploy %s without specifying parameters",
+	"adding %s to ipfs": "adding %s to ipfs",
+	"DApp available at": "DApp available at",
+	"successfully uploaded to ipfs": "successfully uploaded to ipfs",
 	"Ethereum node (version unknown)": "Ethereum node (version unknown)",
 	"No Blockchain node found": "No Blockchain node found",
 	"Couldn't connect to an Ethereum node are you sure it's on?": "Couldn't connect to an Ethereum node are you sure it's on?",
-	"make sure you have an Ethereum node or simulator running. e.g '%s'": "make sure you have an Ethereum node or simulator running. e.g '%s'"
+	"make sure you have an Ethereum node or simulator running. e.g '%s'": "make sure you have an Ethereum node or simulator running. e.g '%s'",
+	"finished building DApp and deploying to": "finished building DApp and deploying to"
 }

lib/pipeline/pipeline.js

@@ -36,6 +36,7 @@ class Pipeline {
       function createImportList(next) {
         importsList["Embark/EmbarkJS"] = fs.dappPath(".embark", 'embark.js');
         importsList["Embark/web3"] = fs.dappPath(".embark", 'web3_instance.js');
+        importsList["Embark/contracts"] = fs.dappPath(".embark/contracts", '');
 
         self.plugins.getPluginsProperty('imports', 'imports').forEach(function (importObject) {
           let [importName, importLocation] = importObject;
@@ -44,15 +45,34 @@ class Pipeline {
 
         next();
       },
-      function writeContracts(next) {
+      function writeContracts(next) {        
         self.events.request('contracts:list', (contracts) => {
-          async.each(contracts, (contract, eachCb) => {
+          // ensure the .embark/contracts directory exists (create if not exists)
-            self.events.request('code-generator:contract', contract.className, (contractCode) => {
+          fs.mkdirp(fs.dappPath(".embark/contracts", ''), (err) => {
-              let filePath = fs.dappPath(".embark", contract.className + '.js');
+            if(err) return next(err);
-              importsList["Embark/contracts/" + contract.className] = filePath;
+
-              fs.writeFile(filePath, contractCode, eachCb);
+            // Create a file .embark/contracts/index.js that requires all contract files
+            // Used to enable alternate import syntax:
+            // e.g. import {Token} from 'Embark/contracts'
+            // e.g. import * as Contracts from 'Embark/contracts'
+            let importsHelperFile = fs.createWriteStream(fs.dappPath(".embark/contracts", 'index.js'));
+            importsHelperFile.write('module.exports = {\n');
+
+            async.eachOf(contracts, (contract, idx, eachCb) => {
+              self.events.request('code-generator:contract', contract.className, (contractCode) => {
+                let filePath = fs.dappPath(".embark/contracts", contract.className + '.js');
+                importsList["Embark/contracts/" + contract.className] = filePath;
+                fs.writeFile(filePath, contractCode, eachCb);
+
+                // add the contract to the exports list to support alternate import syntax
+                importsHelperFile.write(`"${contract.className}": require('./${contract.className}').default`);
+                if(idx < contracts.length - 1) importsHelperFile.write(',\n'); // add a comma if we have more contracts to add
+              });
+            }, function(){
+              importsHelperFile.write('\n}'); // close the module.exports = {} 
+              importsHelperFile.close(next); // close the write stream
             });
-          }, next);
+          });
         });
       },
       function assetFileWrite(next) {