Force Environment Variables to be Strings

This forces any environment variables to be sent to GCF as strings,
even if the value was supplied as a non-string (e.g., number).

Author: pickypg

package/lib/compileFunctions.js

@@ -43,9 +43,12 @@ module.exports = {
       funcTemplate.properties.timeout = _.get(funcObject, 'timeout')
         || _.get(this, 'serverless.service.provider.timeout')
         || '60s';
-      funcTemplate.properties.environmentVariables = _.merge(
-        _.get(this, 'serverless.service.provider.environment'),
-        funcObject.environment,
+      funcTemplate.properties.environmentVariables = _.mapValues(
+        _.merge(
+          _.get(this, 'serverless.service.provider.environment'),
+          funcObject.environment,
+        ),
+        (value) => value.toString()
       );
 
       if (!_.size(funcTemplate.properties.environmentVariables)) {

package/lib/compileFunctions.test.js

@@ -366,6 +366,8 @@ describe('CompileFunctions', () => {
           handler: 'func1',
           environment: {
             TEST_VAR: 'test',
+            TEST_VAR_NUMBER: 123,
+            TEST_VAR_BOOL: false,
           },
           events: [
             { http: 'foo' },
@@ -383,6 +385,8 @@ describe('CompileFunctions', () => {
           availableMemoryMb: 256,
           environmentVariables: {
             TEST_VAR: 'test',
+            TEST_VAR_NUMBER: '123',
+            TEST_VAR_BOOL: 'false',
           },
           timeout: '60s',
           sourceArchiveUrl: 'gs://sls-my-service-dev-12345678/some-path/artifact.zip',