ci: disable caching on travis (#87)

* ci: disable caching on travis

* stop testing on node 8 - it is deprecated. support will officially be dropped when it reaches EOL or when we release 1.0, whichever happens first

* docs: add a deprecation notice for node v8 to the code and readme

Author: dpopp07

.travis.yml

@@ -1,8 +1,9 @@
 language: node_js
 node_js:
-- 8
 - 10
 - 12
+cache:
+  npm: false
 script:
 - npm run test-travis
 after_success:
@@ -13,3 +14,4 @@ deploy:
   script: npx semantic-release
   on:
     node: 12
+    repo: IBM/openapi-validator

README.md

@@ -8,6 +8,10 @@
 
 # OpenAPI Validator
 This command line tool lets you validate OpenAPI documents according to their specification, either [2.0](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/2.0.md) or [3.0](https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.0.md), as well as [custom IBM-defined best practices](http://watson-developer-cloud.github.io/api-guidelines/swagger-coding-style).
+
+#### Notice
+Support for Node v8 is deprecated. Support will be officially dropped when it reaches end of life (31 December 2019) or when v1.0 of this package is released, whichever happens first.
+
 #### Prerequisites
 - Node 8.9.x
 - NPM 5.x

src/cli-validator/index.js

@@ -3,7 +3,7 @@
 // this module enforces that the user is running a supported version
 // of Node by exiting the process if the version is less than
 // the passed in argument (currently 8.9.x)
-require('./utils/enforceVersion')('8.9.0');
+require('./utils/checkVersion')('8.9.0');
 require('./utils/updateNotifier');
 
 const program = require('commander');

src/cli-validator/utils/checkVersion.js

@@ -0,0 +1,30 @@
+const semver = require('semver');
+const chalk = require('chalk');
+
+// this module can be used to handle any version-specific functionality
+// it will be called immediately when the program is run
+
+module.exports = function(requiredVersion) {
+  // this is called since the code uses features that require `requiredVersion`
+  const isSupportedVersion = semver.gte(process.version, requiredVersion);
+  if (!isSupportedVersion) {
+    console.log(
+      '\n' +
+        chalk.red('[Error]') +
+        ` Node version must be ${requiredVersion} or above.` +
+        ` Your current version is ${process.version}\n`
+    );
+    process.exit(2);
+  }
+
+  // print deprecation warnings for specific node versions that will no longer be supported
+  const isNodeEight = semver.satisfies(process.version, '8.x');
+  if (isNodeEight) {
+    console.log(
+      '\n' +
+        chalk.yellow('[Warning]') +
+        ` Support for Node v8 is deprecated. Support will be officially dropped when it reaches end of life` +
+        ` (31 December 2019) or when v1.0 of this package is released, whichever happens first.\n`
+    );
+  }
+};