Fallback to service local serverless installation by default

docs/deprecations.md

@@ -6,6 +6,12 @@ layout: Doc
 
 # Serverless Framework Deprecations
 
+<a name="DISABLE_LOCAL_INSTALLATION_FALLBACK_SETTING"><div>&nbsp;</div></a>
+
+## Support for `enableLocalInstallationFallback` setting is to be removed
+
+Starting with v3.0.0, framework will unconditionally run service local installation of `serverless` if its found.
+
 <a name="LOCAL_INSTALLATION_FALLBACK"><div>&nbsp;</div></a>
 
 ## Fallback to service local `serverless` installation

lib/Serverless.js

@@ -116,40 +116,46 @@ class Serverless {
           });
       });
   }
-  eventuallyFallbackToLocal() {
-    return resolve(process.cwd(), 'serverless').then(
-      ({ realPath }) => {
-        if (realPath === __filename) {
-          this.isLocallyInstalled = true;
-          return null;
-        }
-        if (!this.pluginManager.serverlessConfigFile) return null;
-        if (this.pluginManager.serverlessConfigFile.enableLocalInstallationFallback == null) {
-          this._logDeprecation(
-            'LOCAL_INSTALLATION_FALLBACK',
-            'Local installation of Serverless detected. Starting with next major version, CLI ' +
-              'will run it instead of globally installed version.\n' +
-              'Set "enableLocalInstallationFallback" to "true" to switch to new behavior now, ' +
-              'set to "false" to keep current behavior and hide this message'
-          );
-          return null;
-        }
-        if (!this.pluginManager.serverlessConfigFile.enableLocalInstallationFallback) {
-          return null;
-        }
-        this.cli.log('Running "serverless" installed locally (in service node_modules)');
-        // TODO: Replace below fallback logic with more straightforward one at top of the CLI
-        // when we willl drop support for the "disableLocalInstallationFallback" setting
-        this.isOverridenByLocal = true;
-        const ServerlessLocal = require(realPath);
-        const serverlessLocal = new ServerlessLocal();
-        this.invokedInstance = serverlessLocal;
-        return serverlessLocal.init();
-      },
-      error => {
+  async eventuallyFallbackToLocal() {
+    if (
+      this.pluginManager.serverlessConfigFile &&
+      this.pluginManager.serverlessConfigFile.enableLocalInstallationFallback != null
+    ) {
+      this._logDeprecation(
+        'DISABLE_LOCAL_INSTALLATION_FALLBACK_SETTING',
+        'Starting with next major version, "enableLocalInstallationFallback" setting will no longer be supported.' +
+          'CLI will unconditionally fallback to service local installation when its found.\n' +
+          'Remove this setting to clear this deprecation warning'
+      );
+    }
+    const localServerlessPath = await (async () => {
+      try {
+        return (await resolve(process.cwd(), 'serverless')).realPath;
+      } catch (error) {
         if (!isModuleNotFoundError(error, 'serverless')) throw error;
+        return null;
       }
-    );
+    })();
+    if (!localServerlessPath) return;
+    if (localServerlessPath === __filename) {
+      this.isLocallyInstalled = true;
+      return;
+    }
+    if (
+      this.pluginManager.serverlessConfigFile &&
+      this.pluginManager.serverlessConfigFile.enableLocalInstallationFallback != null &&
+      !this.pluginManager.serverlessConfigFile.enableLocalInstallationFallback
+    ) {
+      return;
+    }
+    this.cli.log('Running "serverless" installed locally (in service node_modules)');
+    // TODO: Replace below fallback logic with more straightforward one at top of the CLI
+    // when we willl drop support for the "disableLocalInstallationFallback" setting
+    this.isOverridenByLocal = true;
+    const ServerlessLocal = require(localServerlessPath);
+    const serverlessLocal = new ServerlessLocal();
+    this.invokedInstance = serverlessLocal;
+    await serverlessLocal.init();
   }
 
   run() {

lib/Serverless.test.js

@@ -307,28 +307,37 @@ describe('Serverless [new tests]', () => {
     after(() => fse.remove(path.resolve(fixtures.map.aws, 'node_modules')));
 
     describe('When running global version', () => {
-      it('Should report deprecation notice when "enableLocalInstallationFallback" not set', () =>
+      it('Should fallback to local version when it is found and "enableLocalInstallationFallback" is not set', () =>
         runServerless({ cwd: fixtures.map.aws, cliArgs: ['-v'] }).then(({ serverless }) => {
-          expect(Array.from(serverless.triggeredDeprecations)).to.deep.equal([
-            'LOCAL_INSTALLATION_FALLBACK',
-          ]);
-          expect(serverless.invokedInstance).to.not.exist;
+          expect(Array.from(serverless.triggeredDeprecations)).to.deep.equal([]);
+          expect(serverless.invokedInstance.isLocalStub).to.be.true;
         }));
-      it('Should run without notice when "enableLocalInstallationFallback" set to false', () =>
+
+      let serverlessWithDisabledLocalInstallationFallback;
+      it('Should report deprecation notice when "enableLocalInstallationFallback" is set', () =>
         fixtures.extend('aws', { enableLocalInstallationFallback: false }).then(fixturePath =>
           runServerless({ cwd: fixturePath, cliArgs: ['-v'] }).then(({ serverless }) => {
-            expect(Array.from(serverless.triggeredDeprecations)).to.deep.equal([]);
-            expect(serverless.invokedInstance).to.not.exist;
+            serverlessWithDisabledLocalInstallationFallback = serverless;
+            expect(Array.from(serverless.triggeredDeprecations)).to.deep.equal([
+              'DISABLE_LOCAL_INSTALLATION_FALLBACK_SETTING',
+            ]);
           })
         ));
+
+      it('Should not fallback to local when "enableLocalInstallationFallback" set to false', () =>
+        expect(serverlessWithDisabledLocalInstallationFallback.invokedInstance).to.not.exist);
+
       it('Should fallback to local version when "enableLocalInstallationFallback" set to true', () =>
         fixtures.extend('aws', { enableLocalInstallationFallback: true }).then(fixturePath =>
           runServerless({ cwd: fixturePath, cliArgs: ['-v'] }).then(({ serverless }) => {
-            expect(Array.from(serverless.triggeredDeprecations)).to.deep.equal([]);
+            expect(Array.from(serverless.triggeredDeprecations)).to.deep.equal([
+              'DISABLE_LOCAL_INSTALLATION_FALLBACK_SETTING',
+            ]);
             expect(serverless.invokedInstance.isLocalStub).to.be.true;
           })
         ));
     });
+
     describe('When running local version', () => {
       it('Should run without notice', () =>
         runServerless({