Merge pull request #193 from fnproject/mww-190404-reverse-up

Update Java FDK string-reverse example

Author: michael-w-williams

examples/README.md

@@ -1,39 +1,39 @@
-# `fn` Java FDK Example Projects
+# Fn Java FDK Example Projects
 
 In this directory you will find some example projects demonstrating different
-features of the `fn` Java FDK:
+features of the Fn Java FDK:
 
 * Plain java code support (`string-reverse`)
 * Functional testing of your functions (`regex-query` and `qr-code`)
 * Built-in JSON coercion (`regex-query`)
 * [InputEvent and OutputEvent](/docs/DataBinding.md) handling (`qr-code`)
 
-## 1. String reverse
+## (1) [String reverse](string-reverse/README.md)
 
 This function takes a string and returns the reverse of the string.
-The `fn` Java FDK runtime will handle marshalling data into your
-functions without the function having to have any knowledge of the FDK API.
+The Fn Java FDK handles marshalling data into your
+functions without the function having any knowledge of the FDK API.
 
-## 2. Regex query
+## (2) Regex query
 
 This function takes a JSON object containing a `text` field and a `regex`
 field and return a JSON object with a list of matches in the `matches`
 field. It demonstrates the builtin JSON support of the fn Java
-wrapper (provided through Jackson) and how the platform handles serialisation
+wrapper (provided through Jackson) and how the platform handles serialization
 of POJO return values.
 
-## 3. QR Code gen
+## (3) QR Code gen
 
 This function parses the query parameters of a GET request (through the
 `InputEvent` passed into the function) to generate a QR code. It demonstrates
 the `InputEvent` and `OutputEvent` interfaces which provide low level
 access to data entering the `fn` Java FDK.
 
-## 4. Asynchronous thumbnails generation
+## (4) Asynchronous thumbnails generation
 
 This example showcases the Fn Flow asynchronous execution API, by
 creating a workflow that takes an image and asynchronously generates three
 thumbnails for it, then uploads them to an object storage.
 
-## 5. Gradle build 
+## (5) Gradle build 
 This shows how to use Gradle to build functions using the Java FDK. 

examples/string-reverse/README.md

@@ -1,71 +1,75 @@
-# Example oFunctions Project: String Reverse
+# Example Java Function: String Reverse
 
-This example provides an HTTP endpoint for reversing strings
+This example provides an HTTP trigger endpoint for reversing strings.
 
 ```bash
-$ curl -d "Hello, World!" "http://localhost:8080/r/string-reverse-app/reverse"
-!dlroW ,olleH
+$ curl -d "Hello World" http://localhost:8080/t/string-reverse-app/string-reverse
+dlroW olleH
 ```
 
 
 ## Demonstrated FDK features
 
-This example uses **no** features of the fn Java FDK; in fact it doesn't have
-a dependency on the fn Java FDK, it just plain old Java code.
+This example uses **none** of the Fn Java FDK features, in fact it doesn't have
+any dependency on the Fn Java FDK.  It is just plain old Java code.
 
 ## Step by step
 
-Ensure you have the functions server running using, this will host your
-function and provide the HTTP endpoints that invoke it:
+Ensure you have the Fn server running to host your
+function and provide the HTTP endpoint that invokes it:
 
-```bash
+(1) Start the server
+
+```sh
 $ fn start
 ```
 
-Build the function locally
+(2) Create an app for the function
 
-```bash
-$ fn build
+```sh
+$ fn create app string-reverse-app
 ```
 
-Create an app and route to host the function
+(3) Deploy the function to your app from the `string-reverse` directory.
 
-```bash
-$ fn create app string-reverse-app
-$ fn create route string-reverse-app /reverse
+```sh
+fn deploy --app string-reverse-app --local
+```
+
+(4) Invoke the function and reverse the string.
+
+```sh
+echo "Hello World" | fn invoke string-reverse-app string-reverse
+dlroW olleH
 ```
 
-Invoke the function to reverse a string
+(5) Invoke the function using curl and  a trigger to reverse a string.
 
 ```bash
-$ curl -d "Hello, World!" "http://localhost:8080/r/string-reverse-app/reverse"
-!dlroW ,olleH
+$ curl -d "Hello World" http://localhost:8080/t/string-reverse-app/string-reverse
+dlroW olleH
 ```
 
 
 ## Code walkthrough
 
 The entrypoint to the function is specified in `func.yaml` in the `cmd` key.
-It is set this to `com.fnproject.fn.examples.StringReverse::reverse`. The whole class
+It is set this to `com.example.fn.StringReverse::reverse`. The whole class
 `StringReverse` is shown below:
 
 
 ```java
-package com.fnproject.fn.examples;
+package com.example.fn;
 
 public class StringReverse {
     public String reverse(String str) {
-        StringBuilder builder = new StringBuilder();
-        for (int i = str.length() - 1; i >= 0; i--) {
-            builder.append(str.charAt(i));
-        }
-        return builder.toString();
+        return new StringBuilder(str).reverse().toString();
     }
 }
 ```
 
-As you can see, this is plain java with no references to the fn API. The
-fn Java FDK handles the marshalling of the HTTP body into the `str`
+As you can see, this is plain java with no references to the Fn API. The
+Fn Java FDK handles the marshalling of the HTTP body into the `str`
 parameter as well as the marshalling of the returned reversed string into the HTTP
 response body (see [Data Binding](/docs/DataBinding.md) for more
 information on how marshalling is performed).

examples/string-reverse/func.yaml

@@ -1,7 +1,11 @@
-name: fn-example/string-reverse
-version: 0.0.1
+schema_version: 20180708
+name: string-reverse
+version: 0.0.2
 runtime: java
-timeout: 30
-format: http
-cmd: com.fnproject.fn.examples.StringReverse::reverse
-path: /reverse
+build_image: fnproject/fn-java-fdk-build:jdk11-1.0.87
+run_image: fnproject/fn-java-fdk:jre11-1.0.87
+cmd: com.example.fn.StringReverse::reverse
+triggers:
+- name: string-reverse
+  type: http
+  source: /string-reverse

examples/string-reverse/pom.xml

@@ -3,23 +3,50 @@
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
-
-
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
-
+        <fdk.version>1.0.87</fdk.version>
     </properties>
-
-    <groupId>com.fnproject.fn.examples</groupId>
+    <groupId>com.example.fn</groupId>
     <artifactId>string-reverse</artifactId>
-    <version>1.0.0-SNAPSHOT</version>
+    <version>1.0.0</version>
+
+    <repositories>
+        <repository>
+            <id>fn-release-repo</id>
+            <url>https://dl.bintray.com/fnproject/fnproject</url>
+            <releases>
+                <enabled>true</enabled>
+            </releases>
+            <snapshots>
+                <enabled>false</enabled>
+            </snapshots>
+        </repository>
+    </repositories>
 
     <dependencies>
+        <dependency>
+            <groupId>com.fnproject.fn</groupId>
+            <artifactId>api</artifactId>
+            <version>${fdk.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.fnproject.fn</groupId>
+            <artifactId>testing-core</artifactId>
+            <version>${fdk.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.fnproject.fn</groupId>
+            <artifactId>testing-junit4</artifactId>
+            <version>${fdk.version}</version>
+            <scope>test</scope>
+        </dependency>
         <dependency>
             <groupId>junit</groupId>
             <artifactId>junit</artifactId>
             <version>4.12</version>
+            <scope>test</scope>
         </dependency>
     </dependencies>
 
@@ -28,27 +55,20 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
-                <version>3.8.0</version>
+                <version>3.3</version>
                 <configuration>
-                    <source>1.8</source>
-                    <target>1.8</target>
+                    <source>8</source>
+                    <target>8</target>
                 </configuration>
             </plugin>
             <plugin>
-                <groupId>org.apache.maven.plugins</groupId>
-                <artifactId>maven-deploy-plugin</artifactId>
-                <version>2.8.2</version>
-                <configuration>
-                    <skip>true</skip>
-                </configuration>
+                 <groupId>org.apache.maven.plugins</groupId>
+                 <artifactId>maven-surefire-plugin</artifactId>
+                 <version>2.22.1</version>
+                 <configuration>
+                     <useSystemClassLoader>false</useSystemClassLoader>
+                 </configuration>
             </plugin>
         </plugins>
     </build>
-
-    <repositories>
-        <repository>
-            <id>fn-maven-releases</id>
-            <url>https://dl.bintray.com/fnproject/fnproject</url>
-        </repository>
-    </repositories>
 </project>

examples/string-reverse/src/main/java/com/example/fn/StringReverse.java

@@ -0,0 +1,7 @@
+package com.example.fn;
+
+public class StringReverse {
+    public String reverse(String str) {
+        return new StringBuilder(str).reverse().toString();
+    }
+}

examples/string-reverse/src/main/java/com/fnproject/fn/examples/StringReverse.java

@@ -1,6 +1,6 @@
-package com.fnproject.examples;
+package com.example.fn.testing;
 
-import com.fnproject.fn.examples.StringReverse;
+import com.example.fn.StringReverse;
 import org.junit.Test;
 
 import static junit.framework.TestCase.assertEquals;