build: transition to circle 2 and cache test fixtures in CI (googleap…

…is#634)

PR-URL: googleapis#634

This change migrates Linux-based CI completely to CircleCI (2.0), and adds caching of `node_modules` (invalidated when either `package-lock.json` or `package.json` change) and `build/test/plugins/fixtures` (invalidated when `test/fixtures/plugin-fixtures.json` changes) to both CircleCI and AppVeyor. This results in a 5-8 min speedup for each test run across CircleCI and AppVeyor.

#### `delete all plugin fixtures`
- Removes all directories in [`test/plugins/fixtures`](https://github.com/GoogleCloudPlatform/cloud-trace-nodejs/tree/v2.4.0/test/plugins/fixtures) in favor of [`plugin-fixtures.json`](https://github.com/kjin/cloud-trace-nodejs/blob/circle-2/test/fixtures/plugin-fixtures.json)
  - This is beneficial because CIs generally invalidate caches when a certain file is changed. Coalescing all the information found in the plugin fixtures makes this a lot easier.
#### `fix CI failures`
- Fixes two CI failures introduced with:
  - Node v9
  - TypeScript v???
#### `modify scripts`
- Names exported functions in scripts rather than using `export default`
- Removes some pre-requisite steps in npm scripts for atomicity
- Adds `encrypt-service-account-credentials` script to regenerate encrypted system test credentials (for future use; this is meant to be used manually and infrequently)
- Modifies `init-test-fixtures` script to generate plugin fixtures based off [`plugin-fixtures.json`](https://github.com/kjin/cloud-trace-nodejs/blob/circle-2/test/fixtures/plugin-fixtures.json) file
- Adds `plugin-fixtures.json`
- Changes code coverage reporter to codecov
#### `update system test key file`
- As Travis (rightfully) doesn't allow me to access encryption details for system test credentials, this commit is the result of running `encrypt-service-account-credentials` to regenerate a new encrypted key file (new encryption details have been added to CircleCI as env vars)
#### `update CI configurations`
- Deletes `.travis.yml` and `circle.yml`
- Adds `.circleci/config.yml` (w/ caching)
- Modifies `appveyor.yml` to add caching and change list of commands to run
#### `update package-lock.json`
- Self-explanatory

.circleci/config.yml

@@ -0,0 +1,121 @@
+---
+# Constant values.
+
+node_modules_cache_key: &node_modules_cache_key node-modules-cache-{{ .Environment.CIRCLE_JOB }}-{{ arch }}-{{ checksum "package.json" }}-{{ checksum "package-lock.json" }}
+test_fixtures_cache_key: &test_fixtures_cache_key test-fixtures-cache-{{ .Environment.CIRCLE_JOB }}-{{ arch }}-{{ checksum "test/fixtures/plugin-fixtures.json" }}
+test_env: &test_env
+  GCLOUD_PROJECT: 0
+  GCLOUD_TRACE_NEW_CONTEXT: 1
+
+# Unit test workflow.
+
+unit_tests: &unit_tests
+  steps:
+    - checkout
+    - run:
+        name: Configure npm to allow running scripts as root
+        command: npm config set unsafe-perm true
+    - restore_cache:
+        key: *node_modules_cache_key
+    - run:
+        name: Install modules and dependencies
+        command: npm install
+    - save_cache:
+        key: *node_modules_cache_key
+        paths:
+          - node_modules
+    - run:
+        name: Check code style and linting
+        command: npm run check
+    - run:
+        name: Compile code
+        command: npm run compile
+    - restore_cache:
+        key: *test_fixtures_cache_key
+    - run:
+        name: Install test fixtures
+        command: npm run init-test-fixtures
+    - save_cache:
+        key: *test_fixtures_cache_key
+        paths:
+          - build/test/plugins/fixtures
+    - run:
+        name: Run unit tests with code coverage
+        command: npm run coverage
+    - run:
+        name: Verify that the package installs OK
+        command: npm run check-install
+    - run:
+        name: Run system tests (skipped for PRs)
+        command: npm run system-test
+
+# Services needed for unit tests.
+
+mongo_service: &mongo_service
+  image: mongo
+
+redis_service: &redis_service
+  image: redis
+
+postgres_service: &postgres_service
+  image: postgres
+  environment:
+    POSTGRES_USER: postgres
+    POSTGRES_PASSWORD: Password12!
+    POSTGRES_DB: test
+
+mysql_service: &mysql_service
+  image: mysql
+  environment:
+    MYSQL_ROOT_PASSWORD: Password12!
+    MYSQL_DATABASE: test
+
+# Main configuration.
+
+version: 2.0
+workflows:
+  version: 2
+  tests:
+    jobs:
+      - node4
+      - node6
+      - node8
+      - node9
+
+jobs:
+  node4:
+    docker:
+      - image: node:4
+        environment: *test_env
+      - *mongo_service
+      - *redis_service
+      - *postgres_service
+      - *mysql_service
+    <<: *unit_tests
+  node6:
+    docker:
+      - image: node:6
+        environment: *test_env
+      - *mongo_service
+      - *redis_service
+      - *postgres_service
+      - *mysql_service
+    <<: *unit_tests
+  node8:
+    docker:
+      - image: node:8
+        environment: *test_env
+      - *mongo_service
+      - *redis_service
+      - *postgres_service
+      - *mysql_service
+    <<: *unit_tests
+  node9:
+    docker:
+      - image: node:9
+        environment: *test_env
+      - *mongo_service
+      - *redis_service
+      - *postgres_service
+      - *mysql_service
+    <<: *unit_tests

appveyor.yml

@@ -6,6 +6,10 @@ environment:
   - nodejs_version: "6"
   - nodejs_version: "8"
 
+cache:
+  - node_modules -> package-lock.json, package.json
+  - build\test\plugins\fixtures -> test\fixtures\plugin-fixtures.json
+
 services:
   - mongodb
   - mysql
@@ -19,8 +23,6 @@ install:
   - nuget install redis-64 -excludeversion
   - redis-64\tools\redis-server.exe --service-install
   - redis-64\tools\redis-server.exe --service-start
-  # install modules
-  - npm install
   - SET GCLOUD_PROJECT=0
   - SET GCLOUD_TRACE_NEW_CONTEXT=1
 
@@ -34,8 +36,16 @@ before_test:
 
 # Post-install test scripts.
 test_script:
+  # install modules
+  - npm install
+  # check code style and linting
+  - npm run check
+  # compile the code
+  - npm run compile
   # check that installing this module is OK
   - npm run check-install
+  # initialize test fixtures
+  - npm run init-test-fixtures
   # run tests
   - npm run test