feat: add a flag, --build.incremental, that turns on incremental buil…

…ds. (#254)

fixes #253

README.md

@@ -181,6 +181,9 @@ Flag to recreate a BuildConfig or Imagestream.  Defaults to false. Choices are "
 #### build.forcePull
 Flag to make your BuildConfig always pull a new image from dockerhub.  Defaults to false
 
+#### build.incremental
+Flag to perform incremental builds(if applicable), which means it reuses artifacts from previously-built images. Defaults to false
+
 #### build.env
 Flag to pass build config environment variables as NAME=Value.  Can be used multiple times.  ex: `nodeshift --build.env NODE_ENV=development --build.env YARN_ENABLED=true`
 
@@ -224,6 +227,9 @@ Shows the below help
             --build.forcePull        flag to make your BuildConfig always pull a new image
                                     from dockerhub or not
                                         [boolean] [choices: true, false] [default: false]
+            --build.incremental  flag to perform incremental builds, which means it reuses
+                                    artifacts from previously-built images
+                                        [boolean] [choices: true, false] [default: false]
             --metadata.out           determines what should be done with the response
                                     metadata from OpenShift
                     [string] [choices: "stdout", "ignore", "<filename>"] [default: "ignore"]

bin/nodeshift

@@ -94,6 +94,12 @@ yargs
     type: 'boolean',
     default: false
   })
+  .options('build.incremental', {
+    describe: 'flag to perform incremental builds, which means it reuses artifacts from previously-built images',
+    choices: [true, false],
+    type: 'boolean',
+    default: false
+  })
   .array('build.env')
   .options('metadata.out', {
     describe: 'determines what should be done with the response metadata from OpenShift',

lib/build-config.js

@@ -93,6 +93,7 @@ async function createOrUpdateBuildConfig (config) {
       outputImageStreamTag: outputImageStreamTag,
       nodeVersion: config.nodeVersion,
       forcePull: config.build.forcePull,
+      incremental: config.build.incremental,
       dockerImage: config.dockerImage,
       buildEnv: config.build.env
     });

lib/definitions/build-strategy.js

@@ -40,6 +40,7 @@ module.exports = (options = {}) => {
         kind: 'DockerImage',
         name: dockerImageName
       },
+      incremental: options.incremental,
       forcePull: options.forcePull
     }
   };

test/definitions-tests/build-strategy-test.js

@@ -31,6 +31,18 @@ test('strategy with changed forcePull to false', (t) => {
   t.end();
 });
 
+test('strategy with changed incremental', (t) => {
+  const result = buildStrategy({incremental: true});
+  t.equal(result.sourceStrategy.incremental, true, 'incremental on');
+  t.end();
+});
+
+test('strategy with changed incremental to false', (t) => {
+  const result = buildStrategy({incremental: false});
+  t.equal(result.sourceStrategy.incremental, false, 'incremental off');
+  t.end();
+});
+
 test('strategy with change dockerImage', (t) => {
   const result = buildStrategy({dockerImage: 'lholmquist/centos7-s2i-nodejs'});