Skip all Documentation Parts overwriting in case of shared API Gateway usage.

src/documentation.js

@@ -92,8 +92,13 @@ module.exports = function() {
         }
       });
     },
+
+    _isSharedApi: function _isSharedApi(){
+      return this.serverless.service.provider.apiGateway ? !!this.serverless.service.provider.apiGateway.restApiId : false;
+    },
 
     _updateDocumentation: function _updateDocumentation() {
+      const serverlessServicePropertyKey = 'serverless-service';
       const aws = this.serverless.providers.aws;
       return aws.request('APIGateway', 'getDocumentationVersion', {
         restApiId: this.restApiId,
@@ -116,7 +121,13 @@ module.exports = function() {
             limit: 9999,
           })
         )
-        .then(results => results.items.map(
+        .then(results => results.items.filter(part => {
+            if (this._isSharedApi()){
+              return JSON.parse(part.properties)[serverlessServicePropertyKey] === this.serverless.service.service;
+            }
+            return true;
+          })          
+          .map(
           part => aws.request('APIGateway', 'deleteDocumentationPart', {
             documentationPartId: part.id,
             restApiId: this.restApiId,
@@ -125,6 +136,9 @@ module.exports = function() {
         .then(promises => Promise.all(promises))
         .then(() => this.documentationParts.reduce((promise, part) => {
           return promise.then(() => {
+            if (this._isSharedApi()) {
+              part.properties[serverlessServicePropertyKey] = this.serverless.service.service;
+            }
             part.properties = JSON.stringify(part.properties);
             return aws.request('APIGateway', 'createDocumentationPart', part);
           });

src/index.spec.js

@@ -3313,6 +3313,48 @@ describe('ServerlessAWSDocumentation', function () {
       });
     });
 
+    it('should not delete another documentation parts in case of shared API usage', function (done) {
+      this.serverlessMock.service.provider.apiGateway = {
+        restApiId: 'superid',
+      };
+
+      this.serverlessMock.providers.aws.request.and.callFake((api, method) => {
+        switch (method) {
+          case 'describeStacks':
+            return Promise.resolve({
+              Stacks: [{
+                Outputs: [{
+                  OutputKey: 'ApiId',
+                  OutputValue: 'superid',
+                }],
+              }],
+            });
+          case 'getDocumentationParts':
+            return Promise.resolve({
+              items: [{
+                id: '123',
+                properties: JSON.stringify({ 'serverless-service': 'service1' })
+              }, {
+                id: '456',
+                properties: JSON.stringify({ 'serverless-service': 'service2' })
+              }],
+            });
+          case 'getDocumentationVersion':
+            return Promise.reject(new Error('Invalid Documentation version specified'));
+          case 'deleteDocumentationPart':
+            return Promise.reject();
+          default:
+            return Promise.resolve();
+        }
+      });
+      this.serverlessMock.providers.aws.naming.getStackName.and.returnValue('superstack');
+
+      this.plugin.afterDeploy().then(() => {
+        expect(this.serverlessMock.providers.aws.request).not.toHaveBeenCalledWith('APIGateway', 'deleteDocumentationPart', jasmine.any(Object));
+        done();
+      });
+    });
+
     it('should generate different documentation versions for different documentation content', function() {
       this.serverlessMock.variables.service.custom.documentation.api = {
         description: 'this is an api',