Expose errors, better requirements checking on CLI arguments (#43)

* Added checking for addresses being provided. Commander doesnt yet provide the ability to set required arguments.

* Add checking for required arguments for time command.

* Reformat uber-time to use Command better

* Update to how the commander CLI library is used. Will output help by default if no arguments given. Added descriptions.

Author: fsargent

src/executables/uber-price.js

@@ -25,19 +25,25 @@ const symbolService = new SymbolService();
 program
   .option('-s, --start <start>', 'specify start address')
   .option('-e, --end <end>', 'specify end address')
-  .option('-u, --unit <unit>', 'specify distance unit')
+  .option('-u, --unit [unit]', 'specify distance unit')
   .parse(process.argv);
 
-try {
-  service.executePriceEstimates(program.start, program.end, program.unit)
-    .then(table => console.log(table))
-    .catch((e) => {
-      if (isDistanceExceededError(e)) {
-        console.log(`Maximum distance of ${symbolService.getMaximumDistanceSymbol()}  miles exceeded between start address: ${program.start} and end address: ${program.end}`);
-      } else {
-        console.error('Could not get price estimates');
-      }
-    });
-} catch (e) {
-  console.error('Could not get price estimates');
+
+if (typeof program.start !== 'string' && typeof program.end !== 'string') {
+  // Output help if there are no arguments or flags.
+  program.outputHelp();
+} else {
+  try {
+    service.executePriceEstimates(program.start, program.end, program.unit)
+      .then(table => console.log(table))
+      .catch((e) => {
+        if (isDistanceExceededError(e)) {
+          console.log(`Maximum distance of ${symbolService.getMaximumDistanceSymbol()}  miles exceeded between start address: ${program.start} and end address: ${program.end}`);
+        } else {
+          console.error('Could not get price estimates:\n', e.message);
+        }
+      });
+  } catch (e) {
+    console.error('Could not get price estimates:\n', e.message);
+  }
 }

src/executables/uber-time.js

@@ -9,12 +9,22 @@ import CommandExecutionService from '../services/CommandExecutionService';
 const service = new CommandExecutionService();
 
 program
-  .arguments('<address>')
-  .action((address) => {
-    try {
-      service.executeTimeEstimates(address).then(table => console.log(table));
-    } catch (Error) {
-      console.error('Could not get time estimates');
-    }
-  })
+  .usage('<address>')
+  .description('Get Time-To-Pickup Estimates')
   .parse(process.argv);
+
+const address = program.args.toString();
+
+if (!address) {
+  program.outputHelp();
+} else {
+  try {
+    service.executeTimeEstimates(address)
+      .then(table => console.log(table))
+      .catch((e) => {
+        console.error('Could not get time estimates:\n', e.message);
+      });
+  } catch (e) {
+    console.error('Could not get time estimates:\n', e.message);
+  }
+}

src/executables/uber.js

@@ -5,6 +5,8 @@ import program from 'commander';
 import pkg from '../../package.json';
 
 program.version(pkg.version)
+  .description('Figure out if you should order a car to pick you up and drive you to where you want to go')
   .command('price', 'get price estimate')
-  .command('time', 'get time to pickup estimate')
+  .command('time [address]', 'get time to pickup estimate')
   .parse(process.argv);
+

src/services/CommandExecutionService.js

@@ -24,12 +24,12 @@ export default class CommandExecutionService {
   }
 
   executePriceEstimates(startAddress, endAddress, distanceUnitName) {
-    if (typeof startAddress !== 'string') {
-      throw new TypeError('start address should be a string');
-    }
-
-    if (typeof endAddress !== 'string') {
-      throw new TypeError('end address should be a string');
+    // commander.js doesn't support required arguments, and will always
+    // interpolate arguments into strings.
+    if (typeof startAddress !== 'string' || typeof endAddress !== 'string') {
+      throw new TypeError(
+        'Start and End addresses (-s \'<address>\' -e \'<address>\') are required.',
+      );
     }
 
     let distanceUnit = DistanceUnit.MILE;
@@ -52,7 +52,7 @@ export default class CommandExecutionService {
 
   executeTimeEstimates(address) {
     if (typeof address !== 'string') {
-      throw new TypeError('address should be a string');
+      throw new TypeError('Address should be a string');
     }
 
     return this.uberService.getTimeEstimates(address)

test/services/CommandExecutionServiceTest.js

@@ -17,12 +17,12 @@ describe('Command Execution Service', () => {
   const service = new CommandExecutionService();
 
   describe('Price estimates', () => {
-    it('throws for invalid start address type', () => {
-      expect(() => service.executePriceEstimates(1, '', DistanceUnit.MILE)).to.throw(TypeError, 'start address should be a string');
+    it('throws for empty start address type', () => {
+      expect(() => service.executePriceEstimates(1, '', DistanceUnit.MILE)).to.throw(TypeError, 'Start and End addresses (-s \'<address>\' -e \'<address>\') are required.');
     });
 
-    it('throws for invalid end address type', () => {
-      expect(() => service.executePriceEstimates('foo', 1, DistanceUnit.MILE)).to.throw(TypeError, 'end address should be a string');
+    it('throws for empty end address type', () => {
+      expect(() => service.executePriceEstimates('foo', null, DistanceUnit.MILE)).to.throw(TypeError, 'Start and End addresses (-s \'<address>\' -e \'<address>\') are required.');
     });
 
     it('throws for undefined distance unit name', () => {
@@ -41,7 +41,7 @@ describe('Command Execution Service', () => {
 
   describe('Time estimates', () => {
     it('throws for invalid address type', () => {
-      expect(() => service.executeTimeEstimates(1)).to.throw(TypeError, 'address should be a string');
+      expect(() => service.executeTimeEstimates(1)).to.throw(TypeError, 'Address should be a string');
     });
 
     it('returns a value', () => {