Now generating templated JSON actor and webfinger responses, which work against a Mastodon user search... the borrowed Thymeleaf config stuff to enable JSON templating has broken the HTML templating though. Sigh.

Java/Spring/activitypubbot/build.gradle

@@ -33,6 +33,7 @@ dependencies {
    	implementation 'org.springframework.boot:spring-boot-starter-actuator'
 	implementation 'org.springframework.shell:spring-shell-starter'
 	implementation 'org.postgresql:postgresql'
+	implementation 'org.thymeleaf:thymeleaf-spring5:3.1.2.RELEASE'
 	testImplementation 'org.springframework.boot:spring-boot-starter-test'
 	testImplementation 'io.projectreactor:reactor-test'
 	testImplementation 'org.springframework.shell:spring-shell-starter-test'

Java/Spring/activitypubbot/src/main/java/dev/activitypub/activitypubbot/BotController.java

@@ -20,12 +20,8 @@ public class BotController {
     @Autowired
     private BotRepo botRepo;
 
-    private BotService botService;
-
     @Autowired
-    public BotController(BotService botService) {
+    private BotService botService;
-        this.botService = botService;
-    }
 
     @GetMapping("/viewbot")
     public String listAll(Model model) {

Java/Spring/activitypubbot/src/main/java/dev/activitypub/activitypubbot/BotRepo.java

@@ -6,5 +6,5 @@ import org.springframework.data.jpa.repository.JpaRepository;
  * Database shenanigans...
  */
 public interface BotRepo extends JpaRepository<Bot, Long> {
- 
+    Bot findByUsername(String username);
 }

Java/Spring/activitypubbot/src/main/java/dev/activitypub/activitypubbot/BotService.java

@@ -25,10 +25,15 @@ public class BotService {
         return repo.save(bot);
     }
 
+    // so far these methods just being calls to repo make me wonder why we need a service in the first place...
     public List<Bot> findAll() {
         return repo.findAll();
     }
 
+    public Bot getBotByUsername( String username ) {
+        return repo.findByUsername( username );
+    }
+
 
     // whilst the URI structure of the below are up to the implementor we're using Mastodon as a reference
 

Java/Spring/activitypubbot/src/main/java/dev/activitypub/activitypubbot/RestHandler.java

@@ -3,6 +3,14 @@ package dev.activitypub.activitypubbot;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.beans.factory.annotation.Qualifier;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.web.server.ResponseStatusException;
+import org.springframework.http.HttpStatus;
+import org.thymeleaf.context.Context;
+import org.thymeleaf.spring5.SpringTemplateEngine;
 
 /**
  * Here we handle any JSON/REST requests, which is how ActivityPub instances talk to each other.
@@ -11,63 +19,58 @@ import org.springframework.web.bind.annotation.RestController;
 @RequestMapping( headers = "accept=application/json" )
 public class RestHandler {
 
+    @Autowired
+    private BotService botServ;
+
+    @Autowired
+    @Qualifier("messageTemplateEngine")
+    protected SpringTemplateEngine jsonTemplater;
+
 	/**
-	 * Really just an alias to /user/springbot
+	 * Really just an alias to /user/<username>
-	 * TODO: how to auto-map @<user> to /users/<user>
 	 */
-	@RequestMapping(value = "/@springbot", headers = "accept=application/json")
+	@RequestMapping(value = "/@{username}", produces = "application/activity+json") // content type based on Masto request
-	public String atactor() {
+	public String atactor(@PathVariable String username) {
-		return this.actor();
+		return this.actor( username );
 	}
 
 	/**
-	 * Access the bot/user - ultimately this should check the database for
+	 * Access the bot/user
-	 * /user/<user> to pull out the relevant data.
 	 */
-	@RequestMapping(value = "/users/springbot", headers = "accept=application/json")
+	@RequestMapping(value = "/users/{username}", produces = "application/activity+json") // content type based on Masto request
-	public String actor() {
+	public String actor(@PathVariable String username) {
-		// TODO: this needs some sort of object wrapper or template, and data in database
-		return """
-{
-	"@context": [
-		"https://www.w3.org/ns/activitystreams",
-		"https://w3id.org/security/v1"
-	],
 
-	"id": "https://springbot.seth.id.au/users/springbot",
+        Bot bot = botServ.getBotByUsername( username );
-	"url": "https://springbot.seth.id.au/@springbot",
+        if( bot == null ) {
-	"inbox": "https://springbot.seth.id.au/users/springbot/inbox",
+            throw new ResponseStatusException( HttpStatus.NOT_FOUND, "These are not the droids you are looking for" );
-	"type": "Person",
+        }
-	"preferredUsername": "springbot",
+		// TODO: kludgetown... we should generate JSON programmatically rather than templates
-	"name": "Spring Bot",
+        final Context ctx = new Context();
-	"manuallyApproveFollowers": false,
+        ctx.setVariable("bot", bot);
-	"indexable": false,
+        final String json = jsonTemplater.process("json/actor", ctx);
-	"published": "2025-01-24T00:00:00Z",
+        return json;
-	"summary": "<p>A bot written using Java/Spring</p>",
-	"publicKey": {
-		"id": "https://springbot.seth.id.au/users/springbot#main-key",
-		"owner": "https://springap.seth.id.au/users/springbot",
-		"publicKeyPem": "-----BEGIN PUBLIC KEY-----\\nMIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA0A5W6M6b+3meJAU0/Fki\\nkMSrEZ6EEThAv4NmyCeDlRbmFQWbh5rWtb69TxkGkkiSFNM3sgg+RSW44Ehn10mL\\nTptfk6oSWFnFHw9MPxmwlWm1Xw8zmp2OMUlI82w11PECFdITJw/1HW73JSVQYfFq\\nWo9rD6nI9G3LPpAB16015NJ9hyeMvz5RA9p9UE540q0l5iJD/l7bxCjHglOQInQX\\neCiR2ErzQSVq3AMhBehoP7HuhKjs8swi8dOgjO3sawqxUyv2+lkesFD2rvxCcXRO\\nBkg/Y7nmJSEcqtcmKYQdObPCIt/wCZNAihJz7dwnGKLE2+JJqPZMer9fAj077OkQ\\neQIDAQAB\\n-----END PUBLIC KEY-----"
-	}
-}""";
 	}
 
 	/**
 	 * Webfinger the user...
 	 */
-	@GetMapping("/.well-known/webfinger")
+	@GetMapping(value = "/.well-known/webfinger", produces = "application/jrd+json") // content type based on Masto request
-	public String webfinger() {
+	public String webfinger(@RequestParam("resource") String resource) {
-		return """
-{
-	"subject": "acct:springbot@springbot.seth.id.au",
 
-	"links": [
+        // resource should be of the form: acct:<username>@<domain> 
-		{
+        // so this should be robustly checked, but for now just yoink out the username
-			"rel": "self",
+        String username = resource.substring(resource.indexOf(":") + 1, resource.indexOf("@"));
-			"type": "application/activity+json",
+        if ( username == null) {
-			"href": "https://springbot.seth.id.au/users/springbot"
+            throw new ResponseStatusException( HttpStatus.NOT_FOUND, "Malformed" );
-		}
+        }
-	]
+        Bot bot = botServ.getBotByUsername( username );
-}""";
+        if( bot == null ) {
-	}
+            throw new ResponseStatusException( HttpStatus.NOT_FOUND, "These are not the droids you are looking for" );
+        }
+		// TODO: kludgetown... we should generate JSON programmatically rather than templates
+        final Context ctx = new Context();
+        ctx.setVariable("bot", bot);
+        final String json = jsonTemplater.process("json/webfinger", ctx);
+        return json;
+    }
 }

Java/Spring/activitypubbot/src/main/java/dev/activitypub/activitypubbot/ThymeleafConf.java

@@ -0,0 +1,99 @@
+package dev.activitypub.activitypubbot;
+// Derived from: https://github.com/RAJNISH3/ThymeLeafApp/blob/master/src/main/java/com/sample/thymeleaf/ThymeleafConfiguration.java
+
+import java.util.Collection;
+import java.util.Collections;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Primary;
+import org.thymeleaf.spring5.SpringTemplateEngine;
+import org.thymeleaf.spring5.templateresolver.SpringResourceTemplateResolver;
+
+@Configuration
+@EnableAutoConfiguration
+public class ThymeleafConf {
+
+    /**
+     * Path to root package/directory in which the different types of message templates are found.
+     */
+    public static final String TEMPLATES_BASE = "classpath:/templates/";
+    /** Pattern relative to templates base used to match JSON templates. */
+    public static final String JSON_TEMPLATES_RESOLVE_PATTERN = "json/*";
+    public static final String HTML_TEMPLATES_RESOLVE_PATTERN = "html/*";
+
+    /**
+     * Creates the template resolver that retrieves text message payloads.
+     *
+     * @return Template resolver.
+     */
+    @Autowired
+    ThymeleafRemoteResourceResolver thymeRemoteConfig;
+    
+
+    /**
+     * Creates the template resolver that retrieves JSON message payloads.
+     *
+     * @return Template resolver.
+     */
+    @Bean
+    public SpringResourceTemplateResolver jsonMessageTemplateResolver() {
+        SpringResourceTemplateResolver theResourceTemplateResolver = new SpringResourceTemplateResolver();
+        theResourceTemplateResolver.setPrefix(TEMPLATES_BASE);
+        theResourceTemplateResolver.setResolvablePatterns(Collections.singleton(JSON_TEMPLATES_RESOLVE_PATTERN));
+        theResourceTemplateResolver.setSuffix(".json");
+        /*
+         * There is no json template mode so the next line has been commented out. Thymeleaf will recognize the ".json"
+         * template resource suffix so there is no need to set a template mode.
+         */
+        // theResourceTemplateResolver.setTemplateMode("json");
+        theResourceTemplateResolver.setCharacterEncoding("UTF-8");
+        theResourceTemplateResolver.setCacheable(false);
+        theResourceTemplateResolver.setOrder(2);
+        return theResourceTemplateResolver;
+    }
+
+    /**
+     * Creates the template resolver that retrieves JSON message payloads.
+     *
+     * @return Template resolver.
+     */
+    @Bean
+    public SpringResourceTemplateResolver htmlMessageTemplateResolver() {
+        SpringResourceTemplateResolver theResourceTemplateResolver = new SpringResourceTemplateResolver();
+        theResourceTemplateResolver.setPrefix(TEMPLATES_BASE);
+        theResourceTemplateResolver.setResolvablePatterns(Collections.singleton(HTML_TEMPLATES_RESOLVE_PATTERN));
+        theResourceTemplateResolver.setSuffix(".html");
+        /*
+         * There is no json template mode so the next line has been commented out. Thymeleaf will recognize the ".json"
+         * template resource suffix so there is no need to set a template mode.
+         */
+        // theResourceTemplateResolver.setTemplateMode("json");
+        theResourceTemplateResolver.setCharacterEncoding("UTF-8");
+        theResourceTemplateResolver.setCacheable(false);
+        theResourceTemplateResolver.setOrder(2);
+        return theResourceTemplateResolver;
+    }
+
+    /**
+     * Creates the template engine for all message templates.
+     *
+     * @param inTemplateResolvers
+     *            Template resolver for different types of messages etc. Note that any template resolvers defined
+     *            elsewhere will also be included in this collection.
+     * @return Template engine.
+     */
+    @Bean
+    public SpringTemplateEngine messageTemplateEngine(
+            final Collection<SpringResourceTemplateResolver> inTemplateResolvers) {
+        final SpringTemplateEngine theTemplateEngine = new SpringTemplateEngine();
+        for (SpringResourceTemplateResolver theTemplateResolver : inTemplateResolvers) {
+            theTemplateEngine.addTemplateResolver(theTemplateResolver);
+            theTemplateEngine.addTemplateResolver(thymeRemoteConfig);
+        }
+        return theTemplateEngine;
+    }
+
+}

Java/Spring/activitypubbot/src/main/java/dev/activitypub/activitypubbot/ThymeleafRemoteResourceResolver.java

@@ -0,0 +1,63 @@
+package dev.activitypub.activitypubbot;
+// From: https://github.com/RAJNISH3/ThymeLeafApp/blob/master/src/main/java/com/sample/thymeleaf/ThymeleafRemoteResourceResolver.java
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
+import java.util.Collections;
+import java.util.Map;
+
+import org.springframework.stereotype.Service;
+import org.thymeleaf.IEngineConfiguration;
+import org.thymeleaf.templateresolver.StringTemplateResolver;
+import org.thymeleaf.templateresource.ITemplateResource;
+
+@Service
+public class ThymeleafRemoteResourceResolver extends StringTemplateResolver {
+
+    private final static String PREFIX = "";
+
+    public ThymeleafRemoteResourceResolver() {
+        setResolvablePatterns(Collections.singleton("*"));
+    }
+    
+    
+    @Override
+    protected ITemplateResource computeTemplateResource(IEngineConfiguration configuration, String ownerTemplate,
+            String template, Map<String, Object> templateResolutionAttributes) {
+
+        // ThymeleafTemplate is our internal object that contains the content.
+        // You should change this to match you're set up.
+        //InputStream inp = this.getClass().getResourceAsStream("/templates/text/personalDetails.txt");//text
+        InputStream inp = this.getClass().getResourceAsStream("/templates/text/personalDtlsLoop.txt");
+                //Thread.currentThread().getContextClassLoader().getResourceAsStream("/templates/text/personalDetails.txt");
+        String s1 = null;
+        try {
+            s1 = convertInputStreamToString(inp);
+        } catch (IOException e) {
+            // TODO Auto-generated catch block
+            e.printStackTrace();
+        }
+        
+        if (inp != null) {
+            return super.computeTemplateResource(configuration, "txt", s1,
+                templateResolutionAttributes);
+        }
+        return null;
+    }
+    private static String convertInputStreamToString(InputStream inputStream) 
+            throws IOException {
+
+            ByteArrayOutputStream result = new ByteArrayOutputStream();
+            byte[] buffer = new byte[1024];
+            int length;
+            while ((length = inputStream.read(buffer)) != -1) {
+                result.write(buffer, 0, length);
+            }
+
+            return result.toString(StandardCharsets.UTF_8.name());
+
+        }
+}

Java/Spring/activitypubbot/src/main/java/dev/activitypub/activitypubbot/WebHandler.java

@@ -2,6 +2,7 @@ package dev.activitypub.activitypubbot;
  
 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.beans.factory.annotation.Autowired;
 import lombok.extern.slf4j.Slf4j;
 
@@ -19,13 +20,13 @@ public class WebHandler {
       * handle requests for our "actor" - this presents the web/html view of
       * the bot
       */	
-    @RequestMapping("/@springbot")
+    @RequestMapping("/@{username}")
-    public String atactor() {
+    public String atactor(@PathVariable String username) {
         log.info("WebHandler::atactor");
-        return this.actor();
+        return this.actor( username );
     }
-    @RequestMapping("/users/springbot")
+    @RequestMapping("/users/{username}")
-    public String actor() {
+    public String actor(@PathVariable String username) {
         log.info("WebHandler::actor");
         return "index"; // just flinging out the index page for now
     }

Java/Spring/activitypubbot/src/main/resources/templates/json/actor.json

@@ -0,0 +1,23 @@
+{
+	"@context": [
+		"https://www.w3.org/ns/activitystreams",
+		"https://w3id.org/security/v1"
+	],
+
+	"id": "https://springbot.seth.id.au/users/[(${bot.username})]",
+	"url": "https://springbot.seth.id.au/@[(${bot.username})]",
+	"inbox": "https://springbot.seth.id.au/users/[(${bot.username})]/inbox",
+	"type": "[(${bot.type})]",
+	"preferredUsername": "[(${bot.username})]",
+	"name": "[(${bot.name})]",
+	"manuallyApproveFollowers": false,
+	"indexable": false,
+	"published": "[(${bot.published})]",
+	"summary": "<p>[(${bot.summary})]</p>",
+	"publicKey": {
+		"id": "https://springbot.seth.id.au/users/[(${bot.username})]#main-key",
+		"owner": "https://springbot.seth.id.au/users/[(${bot.username})]",
+		"publicKeyPem": "-----BEGIN PUBLIC KEY-----\\nMIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA0A5W6M6b+3meJAU0/Fki\\nkMSrEZ6EEThAv4NmyCeDlRbmFQWbh5rWtb69TxkGkkiSFNM3sgg+RSW44Ehn10mL\\nTptfk6oSWFnFHw9MPxmwlWm1Xw8zmp2OMUlI82w11PECFdITJw/1HW73JSVQYfFq\\nWo9rD6nI9G3LPpAB16015NJ9hyeMvz5RA9p9UE540q0l5iJD/l7bxCjHglOQInQX\\neCiR2ErzQSVq3AMhBehoP7HuhKjs8swi8dOgjO3sawqxUyv2+lkesFD2rvxCcXRO\\nBkg/Y7nmJSEcqtcmKYQdObPCIt/wCZNAihJz7dwnGKLE2+JJqPZMer9fAj077OkQ\\neQIDAQAB\\n-----END PUBLIC KEY-----"
+	}
+}
+

Java/Spring/activitypubbot/src/main/resources/templates/json/webfinger.json

@@ -0,0 +1,12 @@
+{
+	"subject": "acct:[(${bot.username})]@springbot.seth.id.au",
+
+	"links": [
+		{
+			"rel": "self",
+			"type": "application/activity+json",
+			"href": "https://springbot.seth.id.au/users/[(${bot.username})]"
+		}
+	]
+}
+