Glen Mazza's Weblog

This entry provides a simple example of using Spring Shell (within Spring Boot) and Micrometer to send custom metrics to Datadog. For a fuller example with Docker and the Datadog Agent, I recommend Datadog Learning Center's free Datadog 101: Developer course. This course will also provide you a free two-week training Datadog account which you can use to receive custom metrics for this example, useful if you don't care to test against your company account. Note custom metrics ordinarily carry billing costs, requiring a paid Datadog account.

Spring Boot already provides numerous web metrics in several areas that can be sent to Datadog without explicit need to capture them. The jvm.* properties, for example, are readable in Datadog's Metrics Explorer, filtering by statistic:value for this example in the "from" field. For custom metrics, we'll have the Spring Shell app commands modify a Timer and a Gauge.

1. Create the Spring Shell application. From Spring Initializr, choose a Java JAR app with Spring Shell and Datadog as dependencies. For some reason I needed to choose the Spring Boot 2.7.x series for an app to download. Prior to running the demo in your IDE (I use IntelliJ), the management.metrics.export.datadog.apiKey=... value needs to be added to the main/resources/application.properties file. Your API key can be determined by logging into Datadog, and from the bottom of the left-side menu, click on your name, then Organization Settings, then Access, the API Keys.

2. Create the shell commands to add to the timer and gauge values:

   package com.example.demo;
   
   import io.micrometer.core.instrument.MeterRegistry;
   import io.micrometer.core.instrument.Tags;
   import io.micrometer.core.instrument.Timer;
   import org.springframework.shell.standard.ShellComponent;
   import org.springframework.shell.standard.ShellMethod;
   
   import java.util.ArrayList;
   import java.util.List;
   import java.util.concurrent.TimeUnit;
   
   @ShellComponent
   public class MyCommands {
   
       private final Timer timer;
   
       private final List<Integer> integerList;
   
       public MyCommands(MeterRegistry registry) {
           timer = registry.timer("demoapp.timer", Tags.empty());
           integerList = registry.gauge("demoapp.listsize", Tags.empty(), new ArrayList<>(), List::size);
       }
   
       @ShellMethod("Note a timer event of given duration in seconds")
       public String timer(int seconds) {
           timer.record(seconds, TimeUnit.SECONDS);
           return "Timer event noted";
       }
       @ShellMethod("Add an element to list")
       public String listAdd() {
           integerList.add(10);
           return "List has " + integerList.size() + " elements";
       }
   
       @ShellMethod("Remove an element from list (if possible)")
       public String listRemove() {
           if (integerList.size() > 0) {
               integerList.remove(integerList.size() - 1);
           }
           return "List has " + integerList.size() + " elements";
       }
   }
   

   For the above we're keeping a gauge on the size of the list, and for the timer, we provide the number of seconds that an arbitrary event took.

3. Run the application and enter several timer #secs, list-add, and list-remove commands. Run -> Run Application from the IntelliJ menu should work fine to enter the commands in the IDE's Console view. To keep the connection with Datadog, keep the command-line app running, even if you're not entering commands. After 2 or 3 minutes, check Datadog's Metrics Explorer to confirm that the demoapp.timer and demoapp.listsize metrics are getting received:

   

   A dashboard can be created to show both properties at once (with separate average time and counts given for the Timer):

   

Resources

• Metrics - Spring Boot docs
• Custom metrics can also be defined via JMX with Datadog's JMX Integration (tutorial)
• Micrometer tutorial - by Baeldung, using Netflix Atlas instead of Datadog

For a Spring Boot application accessing a Flyway-managed MySQL database, I updated its integration tests from using in-memory HSQLDB to Testcontainers' MySQL module. This was both to have testing be done on a database more closely matching deployment environments and also to have various tables pre-populated with standard data provided by our Flyway migration scripts. I'm happy to report that the cost of these benefits was only a slight increase in test running time (perhaps 10-15% more time), and that despite there being 170 Flyway migrations at that time of the conversion.

It is best to use Testcontainers when starting to develop the application, so any hiccups found in a Flyway migration file can be fixed before that migration file becomes final. Switching to testcontainers after-the-fact uncovered problems with some of our migration scripts requiring additional configuration of the MySQL testcontainer. The main problems were unnecessary explicit specification of the schema name in the scripts, and a suboptimal definition of a table that required explicit_defaults_for_timestamp to be configured in MySQL. This configuration was in our deployment my.cnf files but not in the default one used by the MySQL testcontainer.

Solving the first issue involved explicit specification of the username, password, and database name when creating the Testcontainers instance. Initializing the MySQL container just once for all integration tests is sufficient for our particular application, so TC's Manual container lifecycle control which uses Java configuration was used:

@SpringBootTest
@ActiveProfiles("itest")
public class MyAppIntegrationTest {

    private static final MySQLContainer MY_SQL_CONTAINER;

    static {
        MY_SQL_CONTAINER = new MySQLContainer("mysql:5.7")
                .withUsername("myappUser")
                .withPassword("myappPass")
                .withDatabaseName("myapp");
        MY_SQL_CONTAINER.start();
    }

    @DynamicPropertySource
    public static void containersProperties(DynamicPropertyRegistry registry) {
        registry.add("spring.datasource.username", MY_SQL_CONTAINER::getUsername);
        registry.add("spring.datasource.password", MY_SQL_CONTAINER::getPassword);
        registry.add("spring.datasource.url", MY_SQL_CONTAINER::getJdbcUrl);
    }
}

The containersProperties call dynamically populates the given Spring boot config values with those provided from the MySQL testcontainer. Note the spring.datasource.url will be a "regular" MySQL URL, i.e., Spring Boot and Flyway are unaware that the database is a Testcontainers-provided one.

When doing Java-based instantiation of the MySQL instance as above, I've found adding the standard property file configuration of the MySQL testcontainer to be unnecessary and best avoided -- doing so appeared to create a second, unused, container instance, slowing down builds. However, if you choose to use properties-only Java configuration (perhaps wishing to instantiate and initialize MySQL testcontainers more frequently during the integration tests), configuration similar to the below should work. Note the "myappdatabase", "myuser" and "mypass" values given in the url property are used to tell Testcontainers the values to set when creating the database and the user. In turn, whatever values placed here should go into the standard Spring username and password properties as shown:

spring.flyway.enabled=true
spring.datasource.url=jdbc:tc:mysql:5.7://localhost/myappdatabase?user=myuser&password=mypass
spring.datasource.driver-class-name=org.testcontainers.jdbc.ContainerDatabaseDriver
spring.datasource.username=myuser
spring.datasource.password=mypass

Fixing the second issue involved using a different my.cnf for the MySQL testcontainer. To accomplish that I copied the mysql-default-conf/my.cnf directory and file from the org.testcontainers.mysql:1.17.6 library (easily viewable from IntelliJ IDEA) and pasted it as src/itest/resources/mysql-default-conf/my.cnf in the Spring Boot application. From the latter location I added my needed change.

Notes:

• The Gradle dependencies used to activate the MySQL testcontainer in the integration test environment:

  configurations {
      integrationTestImplementation.extendsFrom testImplementation
      integrationTestRuntimeOnly.extendsFrom testRuntimeOnly
  }
  
  dependencies {
      integrationTestImplementation 'org.springframework.boot:spring-boot-starter-test'
      integrationTestImplementation 'org.testcontainers:mysql'
      integrationTestImplementation 'org.testcontainers:junit-jupiter'
  }
  

• As the migrations are kept in the main/resources folder, in the standard db/migration subdirectory, I thought I could perhaps just create overriding migrations in the corresponding itest/resources subdirectory for the few migrations with problems, and that Flyway would use the overrides over the ones in the main/resources folder. That did not work, though, Flyway halts with a complaint about duplicate filenames between the two folder locations.

Further resources:

• One-Stop Guide to Database Migration with Flyway and Spring Boot - Article from Reflectoring.io covering Spring Boot and Flyway together (not Testcontainers-specific).
• Execute Flyway Database Migrations on Startup - SpringBoot docs

I've added support for the Composite API to my Salesforce CRM Java client, in particular for updates and inserts. This API method allows for up to 25 subrequests at the cost of just one API call (with a few other limitations depending on the types of calls made). For insertion-only requests, where the items being inserted are not related to each other, the Multiple Record Insertion technique added earlier to the client is probably best, as it allows for up to 200 insertions in one API call.

For tl;dr; purposes, reviewing the testMultipleEntityRecordInsertionsAndCompositeCalls() test case shows how a Composite API call can be made with this client. The sample makes one request consisting of one insert and two updates, and shows how to obtain the fields returned in both success and error scenarios. An example Multiple Record Insertion technique is in the same test.

As shown in the Salesforce docs, composite calls consist of a series of objects with four fields: method, url, referenceId, and body:

{
"compositeRequest" : [{
  "method" : "POST",
  "url" : "/services/data/v57.0/sobjects/Account",
  "referenceId" : "refAccount",
  "body" : { "Name" : "Sample Account" }
  },{
  "method" : "POST",
  "url" : "/services/data/v57.0/sobjects/Contact",
  "referenceId" : "refContact",
  "body" : { 
    "LastName" : "Sample Contact",
    "AccountId" : "@{refAccount.id}"
    }
  }]
}

The method will be POST for inserts and PATCH for updates, while the url field refers to the object being inserted/updated. Example URL formats for Accounts:

• Inserts: /services/data/vXX.X/sobjects/Account

• Updates: /services/data/vXX.X/sobjects/Account/id/(SF ref ID of Account)

To provide these fields, the client provides an abstract CompositeEntityRecord, taking care of all fields but the body, the latter to be provided by subclasses the developer creates.

public abstract class CompositeEntityRecord {

    @JsonIgnore
    private final String entity;
    private final String referenceId;
    private final Method method;
    // URL dynamically generated when making request
    private String url;

    // getters and setters
}

The entity is @JsonIgnored as it is not part of the JSON object sent to Salesforce. As the URL contains the Salesforce API version and other call-specific data, it will be dynamically generated by the SalesforceCompositeRequestService at the time of the call. A sample CompositeEntityRecord subclass, to update an Account's site and number of employees:

public class AccountUpdateCompositeRecord extends CompositeEntityRecord {

    private Body body = new Body();

    public AccountUpdateCompositeRecord(String referenceId) {
        super("Account", Method.PATCH, referenceId);
        
    }

    public Body getBody() {
        return body;
    }

    public static class Body {
        public int numberOfEmployees;
        public String site;

        // getters and setters
    }
}

For updates, the id should not be placed in the body, that will instead be placed in the url field at the time of the service call (below). The referenceId needs to be a unique value for all subrequests of the composite request. For updates, the SF ID of the object being updated (unless you're updating one item multiple times in the same call) would be an excellent fit.

Insertions will normally involve more fields, so it will be usually necessary to create another subclass with its additional fields. Also, there won't be a SF ID yet, so just choose a unique string for each reference ID in the composite call. In the response coming back, use the same ID to obtain the subrequest's results.

public class AccountInsertCompositeRecord extends CompositeEntityRecord {

    private final Body body = new Body();

    public AccountInsertCompositeRecord(String referenceId) {
        super("Account", Method.POST, referenceId);
    }

    public Body getBody() {
        return body;
    }

    public static class Body {
         ....
    }

The client provides a CompositeEntityRecordRequest to hold all the subrequests:

public class CompositeEntityRecordRequest {

    boolean allOrNone;

    List<? extends CompositeEntityRecord> compositeRequest;

    public CompositeEntityRecordRequest(boolean allOrNone) {
        this.allOrNone = allOrNone;
    }

    // getters and setters

}

See the Salesforce Docs for the usage of allOrNone, due to its importance it is placed in the constructor to require it to be specified. For the response returned by the Composite API call, the CompositeEntityRecordResponse class below is used. The format of the result body returned from Salesforce is unfortunately different in the success (Map) and failure cases (List of Map), so the Result.body field is declared as an Object. However, there are helper methods getSuccessResultsMap() and getErrorResultsList() in the Result object to help you parse the body (see the client test case mentioned above for an example of both). By first reading the Result's httpStatusCode you can determine the proper method to call.

package net.glenmazza.sfclient.model;

import java.util.List;
import java.util.Map;

public class CompositeEntityRecordResponse {

    List<Result> compositeResponse;

    // getters and setters

    public static class Result {
        private int httpStatusCode;
        private String referenceId;
        private Map<String, String> httpHeaders;
        private Object body;

        // getters and setters 

        public Map<String, Object> getSuccessResultsMap() {
           // ...
        }

        public List<Map<String, Object>> getErrorResultsList() {
           // ...
        }

    }
}

As shown in the test case, once the CompositeEntityRecordRequest object is created, a call to the client's SalesforceCompositeRequestService is straightforward:

CompositeEntityRecordResponse cerr = scrs.bulkProcess(cerReq);

Further Resources:

• How to Use Salesforce Composite Rest API - Roycon website

Updated May 2023.

I've made available on GitHub a Spring Security-based client library for making OAuth2-enabled REST calls to Salesforce CRM's API. The library supports use of Salesforce's:

• REST API

• SOQL Query: These are handled by the SOQLQueryRunner which provides two options for responses: a JSON-formatted string or a developer-defined parameterized implementation of SOQLQueryResponse (example in the integrated test). The latter takes advantage of the fact that SOQL queries share much common structure and need only a relatively small portion to be overridden to hold fields specific to the SOQL query.

• Apex REST

• Multiple Record Insertion: See Inserting multiple Salesforce CRM records with a single API call for more details.

• Composite API: See Composite API added to Salesforce CRM Java Client for more details.

For authentication, supported are Salesforce's JWT Bearer Token and username/password flows discussed in my earlier blog post. Spring Security's OAuth 2 client are used to obtain access tokens necessary for making these calls.

The integrated test cases give examples of the client in action. As they involve creating, updating, and deleting Salesforce Accounts they should be run against a non-production instance. Salesforce offers free developer instances. Note the test case for the Apex REST functionality will require installing this Apex REST endpoint from the Salesforce documentation. To run the tests, first create an application-test.properties file in the itest resources folder with the configuration necessary for the flow you are using. There is a template file in that folder specifying what is needed for each OAuth2 flow type. For usage of this library by other applications, this configuration would be placed in the importing application's properties file. The library's SalesforceOAuth2Config class reads that configuration, and will halt on startup with informational messages if anything needed is missing. Once done, the integrated tests can be run from IntelliJ or command-line via ./gradlew integratedTest.

The Username/Password flow is supported out of the box by Spring, but the JWT bearer token flow requires some extra classes implemented in the client:

• SalesforceJwtBearerOAuth2AuthorizedClientProvider - For each outgoing request to a resource server, checks if the JWT Bearer Token method is being used for access tokens and also if an authorized client (i.e., one with a valid access token) is already available. If yes and no, respectively, initiates the process to obtain a new access token to use with the resource API call.
• OAuth2SalesforceJwtBearerGrantRequest - created by above class, it holds the information necessary to create the JWT bearer token for making an access token request.
• OAuth2SalesforceJwtBearerGrantRequestEntityConverter - Constructs the JWT bearer token
• SalesforceJwtBearerTokenResponseClient - Uses the JWT Bearer token created by the above class to obtain a new access token from the authorization server.

What happens when access tokens expire? The WebClient calls have a retry(1) setting that allows for one additional call to the resource server in case of an error such as using an expired access token. In such cases, for the first call, the failure handler in SalesforceOAuth2Config removes the authorized client instance (which has the invalid access token) from memory. For the retry call, SalesforceJwtBearerOAuth2AuthorizedClientProvider notes that there is not an authorized client instance anymore so proceeds to obtain a new access token to allow the second call to proceed. This functionality can be verified by revoking the access token from either Salesforce Setup's Session Management screen or from Connected Apps usage, and confirming that a subsequent resource API call still provides the data. Code breakpoints can also be used to confirm another access token was requested.

Additional Resources

• OAuth 2.0 Client - official Spring documentation
• Carey Development - Blog contains many useful tutorials, including on logging exceptions and reporting them to clients helpful for the creation of this client library.
• Spring WebClient – GET, PUT, POST, DELETE examples
• Spring 5 WebClient and WebTestClient Tutorial with Examples
• Salesforce Username/Password Flow Example - Very helpful in creating the Username-Password flow option in this library.

Basit-Mahmood Ahmed has provided a nice example of adding a custom grant to Spring Authorization Server, providing a replacement for the "resource owner" grant removed from the OAuth 2.1 standard. I was able to leverage that for providing our own resource owner implementation. At work we've needed to create several types of custom grants, thankfully what started off as perplexing to implement, due to repetition became rather routine. Best starting advice I can to examine the out-of-the-box provided grant types and follow along with them. The Reference Guide of course and YouTube videos are also valuable, for example Getting Started with Spring Authorization Server and Configuring and Extending Spring Authorization Server.

For each custom grant type to support under Spring Auth Server, I've normally found five extra source files needed, as well as adjusting a couple of others. Most classes are limited in responsibilities helping keep their creation straightforward. Providing links to Basit-Mahmood's example where applicable, as well as some unrelated additional code samples:

1. The custom grant Token class (example): Extending OAuth2AuthorizationGrantAuthenticationToken, this class holds the properties used by the Provider (discussed below) to authenticate the client. For the resource owner grant, it would have username and password. For a grant based on incoming IP Address, it would be an IP address string. This class is also a good place to define the custom token grant_type parameter used in the OAuth2 token request.

2. The custom grant Converter class (example): This class takes the incoming HttpServletRequest and, by reading its properties, creates an instance of the Token class. Parameter validation for obvious shortcomings (missing param values, etc.) are good to do here, to help keep the Provider uncluttered.

3. The Provider class (example): This class takes the Token created by the Converter and authenticates and authorizes the grant. In general, there are two parts to this: authentication of the token, frequently handled by two other classes, discussed below, followed by construction of the JWT, partly in the Provider and partly in the OAuth2TokenCustomizer discussed below.

4. A token to represent the resource owner. This class will extend from AbstractAuthenticationToken, and will be used both to authenticate a user and to represent the user after authentication.

   package ...;
   
   
   import org.springframework.security.authentication.AbstractAuthenticationToken;
   import org.springframework.security.core.GrantedAuthority;
   ...
   
   public class MyInnerAuthenticationToken extends AbstractAuthenticationToken {
   
       private final MyAccessUser myAccessUser;
   
       // constructor for user-to-validate	
       public MyInnerAuthenticationToken(String propertyToCheck) {
           super(null);
           this.myAccessUser = new MyAccessUser(propertyToCheck);
       }
   
       // constructor for validated user
       public MyInnerAuthenticationToken(MyAccessUser myAccessUser,
                                          Collection authorities) {
           super(authorities);
           this.myAccessUser = myAccessUser;
           super.setAuthenticated(true); // must use super, as we override
       }
   
       @Override
       public Object getPrincipal() {
           return this.myAccessUser;
       }
   
       @Override
       public void setAuthenticated(boolean isAuthenticated) throws IllegalArgumentException {
           Assert.isTrue(!isAuthenticated,
                   "Cannot set this token to trusted - use constructor which takes a GrantedAuthority list instead");
           super.setAuthenticated(false);
       }
   
       @Override
       public String getName() {
           return this.myAccessUser.getName();
       }
   }
   

5. Another Provider to authenticate the above token. This would be called by the OAuth2 grant Provider during authentication. This Provider implements the standard authenticate(Authentication) method, returning a new Token populated with the principal and its authorities.

   @Service
   public class MyInnerAuthenticationProvider implements AuthenticationProvider {
   
       private static final Logger LOGGER = LoggerFactory.getLogger(MyInnerAuthenticationProvider.class);
   
       @Autowired
       private MyAuthenticator authenticator;
   
       @Override
       public Authentication authenticate(Authentication authentication) throws AuthenticationException {
           MyAccessUser unvalidatedUser = (MyAccessUser) authentication.getPrincipal();
           String ip = unvalidatedUser.getIpAddress();
   
           MyAccessUser validatedAccessUser = authenticator.checkIpAddress(ip);
           if (validatedIPAccessUser != null) {
               Collection<GrantedAuthority> authorities = authenticator.toGrantedAuthorities(
                       validatedAccessUser.getPermissions());
               return new MyInnerAuthenticationToken(validatedAccessUser, authorities);
           } else {
               LOGGER.warn("Could not validate user {}", unvalidatedUser);
               return null;
           }
       }
   
       @Override
       public boolean supports(Class<?> authentication) {
           return MyInnerAuthenticationToken.class.isAssignableFrom(authentication);
       }
   }
   

6. Spring Authorization Server allows for creating an OAuth2TokenCustomizer implementation for adding claims to a JWT common to multiple grant types. It should get picked up automatically by the framework's JwtGenerator. If you've created one, good to review at this stage any adjustments or additions that can be made to it as a result of the new custom grant.

   @Component
   public class MyTokenCustomizer implements OAuth2TokenCustomizer {
   
       public void customize(JwtEncodingContext context) {
           JwtClaimsSet.Builder claimsBuilder = context.getClaims();
           claimsBuilder.claim(ENVIRONMENT_ID, environment);
   
           // Spring Auth Server's JwtGenerator does not provide JTI by default
           claimsBuilder.claim(JwtClaimNames.JTI, UUID.randomUUID().toString());
   
           Authentication token = context.getPrincipal();
   
           // can add principal-specific claims:
           if (token.getPrincipal() instanceof MySubjectClass chiefJwtSubject) {
              ... 
           }
       }
   }
   

Once completed, now time to wire new grant support within the authorization server. To wire up the grant-level Converter and Provider, within a WebSecurityConfigurerAdapter subclass:

List converters = new ArrayList<>();
converters.add(resourceOwnerPasswordAuthenticationConverter);

authorizationServerConfigurer
        .tokenEndpoint(tokenEndpoint -> {
            tokenEndpoint.accessTokenRequestConverter(new DelegatingAuthenticationConverter(
                converters))
                // lots more providers
                .authenticationProvider(resourceOwnerPasswordAuthenticationProvider)
            }
        );

The mini-level Provider, used for the actual authentication of the User, can be configured separately as a @Bean:

@Bean
public MyInnerAuthenticationProvider myInnerAuthenticationProvider() {
    return new MyInnerAuthenticationProvider();
}

Once developed, easy to test with Postman. Spring Auth Server uses an oauth2_registered_client table where the client_id and client_secret for clients are defined. Within Postman, Authorization tab, choose Basic Auth type and enter the client ID and secret as the credentials:

Then the new grant type can be tested with a POST call to the standard oauth/token endpoint using that grant_type: