Add ballerina runtime support

.gitignore

@@ -141,6 +141,11 @@ artifacts/
 *.nuget.props
 *.nuget.targets
 
+# IDEA Files
+.idea/
+*.iml
+*.ipr
+*.iws
 
 # Kubeless specific
 bats/

docker/runtime/ballerina/Dockerfile

@@ -0,0 +1,11 @@
+FROM ballerina/ballerina-platform:0.970.1
+
+USER 1000
+
+WORKDIR /kubeless
+
+ENV FUNC_PROCESS="ballerina run kubeless_run.balx -c kubeless.toml"
+
+ADD proxy /
+
+CMD [ "/proxy" ]

docker/runtime/ballerina/Dockerfile.init

@@ -0,0 +1,9 @@
+FROM ballerina/ballerina-platform:0.970.1
+
+USER 1000
+
+# Install controller & Kubeless type definitions
+ADD kubeless_run.tpl.bal /ballerina/files/src/
+ADD kubeless/kubeless.bal /ballerina/files/kubeless/
+
+ENTRYPOINT [""]

docker/runtime/ballerina/Makefile

@@ -0,0 +1,16 @@
+init-image:
+	docker build -f Dockerfile.init -t kubeless/ballerina-init:0.970.1 .
+
+runtime-image:
+	env GOOS=linux GOARCH=amd64 go build $$GOPATH/src/github.com/kubeless/kubeless/pkg/function-proxy/proxy.go
+	docker build -f Dockerfile -t kubeless/ballerina:0.970.1 .
+
+push-init:
+	docker push kubeless/ballerina-init:0.970.1
+
+push-runtime:
+	docker push kubeless/ballerina:0.970.1
+
+# Mandatory jobs
+build-all: init-image runtime-image
+push-all: push-init push-runtime

docker/runtime/ballerina/example/foo.bal

@@ -0,0 +1,8 @@
+import kubeless;
+import ballerina/io;
+
+public function foo(kubeless:Event event, kubeless:Context context) returns (string|error) {
+    io:println(event);
+    io:println(context);
+    return "bar";
+}

docker/runtime/ballerina/kubeless/kubeless.bal

@@ -0,0 +1,15 @@
+public type Event{
+    string data;
+    string event_id;
+    string event_type;
+    string event_time;
+    string event_namespace;
+    map extensions;
+};
+
+public type Context{
+    string function_name;
+    string time_out;
+    string runtime;
+    string memory_limit;
+};

docker/runtime/ballerina/kubeless_run.tpl.bal

@@ -0,0 +1,116 @@
+// Copyright (c) 2017-2018 Bitnami
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+//     http://www.apache.org/licenses/LICENSE-2.0
+
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import ballerina/http;
+import ballerina/io;
+import ballerina/config;
+import func;
+import kubeless;
+
+// A service endpoint represents a listener
+endpoint http:Listener listener {
+    //Listner port is 8090 redirected by proxy
+    port: 8090
+};
+
+@http:ServiceConfig {
+    basePath: "/",
+    compression: "NEVER"
+}
+
+service<http:Service> controller bind listener {
+    //Initialize context from environment variables
+    kubeless:Context context = {
+        function_name: config:getAsString("FUNC_HANDLER"),
+        time_out: config:getAsString("FUNC_TIMEOUT"),
+        runtime: config:getAsString("FUNC_RUNTIME"),
+        memory_limit: config:getAsString("FUNC_MEMORY_LIMIT")
+    };
+
+    @http:ResourceConfig {
+        methods: ["GET", "POST", "DELETE", "PATCH", "PUT"],
+        path: "/"
+    }
+    handler(endpoint caller, http:Request request) {
+        kubeless:Event event = {};
+        //Read requests and set them to event
+        if (request.hasHeader("Content-Length")){
+            int|error result = <int>request.getHeader("Content-Length");
+            match result {
+                int legnth => {
+                    if (legnth > 0){
+                        match request.getPayloadAsString() {
+                            string payload => {
+                                event.data = payload;
+                            }
+                            error e => {
+                                io:println("Error while extracting payload: " + e.message);
+                            }
+                        }
+                    }
+                }
+                error e => {
+                    io:println("Error while reading header: " + e.message);
+                }
+            }
+        }
+        //Read headers and set event info.
+        if (request.hasHeader("event-id")){
+            event.event_id = request.getHeader("event-id");
+        }
+        if (request.hasHeader("event-type")){
+            event.event_type = request.getHeader("event-type");
+        }
+        if (request.hasHeader("event-time")){
+            event.event_time = request.getHeader("event-time");
+        }
+        if (request.hasHeader("event-namespace")){
+            event.event_namespace = request.getHeader("event-namespace");
+        }
+        // Create object to carry data back to caller
+        http:Response response = new;
+
+        // Invoke function and set the response payload.
+        string response_payload;
+        match func:<<FUNCTION>>(event, context) {
+            string return_value => {
+                response_payload = return_value;
+            }
+            error e => {
+                response_payload = e.message;
+            }
+        }
+        response.setPayload(response_payload);
+        // Send a response back to caller
+        // Errors are ignored with '_'
+        // -> indicates a synchronous network-bound call
+        _ = caller->respond(response);
+    }
+
+    // Health check resource
+    @http:ResourceConfig {
+        methods: ["GET", "POST"],
+        path: "/healthz"
+    }
+    health(endpoint caller, http:Request request) {
+
+        http:Response response = new;
+        response.statusCode = http:OK_200;
+
+        // Send a response back to caller
+        // Errors are ignored with '_'
+        // -> indicates a synchronous network-bound call
+        _ = caller->respond(response);
+    }
+}

docs/runtimes.md

@@ -8,13 +8,14 @@ By default Kubeless has support for the following runtimes:
  - PHP: For the branch 7.2
  - Golang: For the branch 1.10
  - .NET: For the branch 2.0
+ - Ballerina: For the branch 0.970.1
 
 You can see the list of supported runtimes executing:
 
 ```console
 $ kubeless get-server-config
 INFO[0000] Current Server Config:
-INFO[0000] Supported Runtimes are: python2.7, python3.4, python3.6, nodejs6, nodejs8, ruby2.4, php7.2, go1.10
+INFO[0000] Supported Runtimes are: python2.7, python3.4, python3.6, nodejs6, nodejs8, ruby2.4, php7.2, go1.10, dotnetcore2.0, java1.8, ballerina0.970.1
 ```
 
 Each runtime is encapsulated in a container image. The reference to these images are injected in the Kubeless configuration. You can find the source code of all runtimes in [`docker/runtime`](https://github.com/kubeless/kubeless/tree/master/docker/runtime).
@@ -348,6 +349,52 @@ You can deploy them using the command:
 kubeless function deploy fibonacci --from-file fibonacci.cs --handler module.handler --dependencies fibonacci.csproj --runtime dotnetcore2.0
 ```
 
+### Ballerina
+
+#### Example
+
+```ballerina
+import kubeless;
+import ballerina/io;
+
+public function foo(kubeless:Event event, kubeless:Context context) returns (string|error) {
+    io:println(event);
+    io:println(context);
+    return "Hello Ballerina";
+}
+
+```
+
+#### Description
+
+The Ballerina functions should import the package `kubeless`. This [package](../docker/runtime/ballerina/kubeless/kubeless.bal) contains two types `Event` and `Context`. 
+
+```console
+$ kubeless function deploy foo 
+    --runtime ballerina0.970.1 
+    --from-file foo.bal 
+    --handler foo.foo 
+```
+
+When using the Ballerina runtime, it is possible to provide a configuration via `kubeless.toml` file. The values in kubeless.toml file are available for the function. The function(.bal file) and conf file should be in the same directory.
+The zip file containing both files should be passed to the Kubeless CLI.
+```console
+foo
+├── hellowithconf.bal
+└── kubeless.toml
+
+$ zip -r -j foo.zip foo/
+
+$ kubeless function deploy get-ballerina-conf 
+      --runtime ballerina0.970.1 
+      --from-file foo.zip 
+      --handler hellowithconf.foo
+```
+
+#### Server implementation
+
+For the Ballerina runtime we start a [Ballerina HTTP server](../docker/runtime/ballerina/kubeless_run.tpl.bal) with two resources, '/' and '/healthz'.
+
 ## Use a custom runtime
 
 The Kubeless configuration defines a set of default container images per supported runtime variant.

examples/Makefile

@@ -798,3 +798,30 @@ get-nodejs-distroless:
 
 get-nodejs-distroless-verify:
 	kubeless function call get-nodejs-distroless |egrep hello.world
+
+get-ballerina:
+	kubeless function deploy get-ballerina --runtime ballerina0.970.1 --from-file ballerina/helloget.bal --handler helloget.foo
+
+get-ballerina-verify:
+	kubeless function call get-ballerina |egrep Hello.World.Ballerina
+
+get-ballerina-custom-port:
+	kubeless function deploy get-ballerina-custom-port --runtime ballerina0.970.1 --handler helloget.foo --from-file ballerina/helloget.bal --port 8083
+
+get-ballerina-custom-port-verify:
+	kubectl get svc get-ballerina-custom-port -o yaml | grep 'targetPort: 8083'
+	kubeless function call get-ballerina-custom-port |egrep Hello.World.Ballerina
+
+get-ballerina-data:
+	kubeless function deploy get-ballerina-data --runtime ballerina0.970.1 --from-file ballerina/hellowithdata.bal --handler hellowithdata.foo
+
+get-ballerina-data-verify:
+	kubeless function call get-ballerina-data --data '{"hello":"world"}' |egrep hello
+
+get-ballerina-conf:
+	zip -r -j ballerina/bar.zip ballerina/hello_with_conf/
+	kubeless function deploy get-ballerina-conf --runtime ballerina0.970.1 --from-file ballerina/bar.zip --handler hello_with_conf.bar
+	rm ballerina/bar.zip
+
+get-ballerina-conf-verify:
+	kubeless function call get-ballerina-conf | egrep john

examples/ballerina/hello_with_conf/hello_with_conf.bal

@@ -0,0 +1,9 @@
+import kubeless;
+import ballerina/io;
+import ballerina/config;
+
+public function bar(kubeless:Event event, kubeless:Context context) returns (string|error) {
+    io:println(event);
+    io:println(context);
+    return config:getAsString("hello.userid");
+}

examples/ballerina/hello_with_conf/kubeless.toml

@@ -0,0 +1,2 @@
+[hello]
+userid="john@ballerina.com"

examples/ballerina/helloget.bal

@@ -0,0 +1,5 @@
+import kubeless;
+
+public function foo(kubeless:Event event, kubeless:Context context) returns (string|error) {
+    return "Hello World Ballerina";
+}

examples/ballerina/hellowithdata.bal

@@ -0,0 +1,8 @@
+import kubeless;
+import ballerina/io;
+
+public function foo(kubeless:Event event, kubeless:Context context) returns (string|error) {
+    io:println(event);
+    io:println(context);
+    return <string>event.data;
+}

kubeless-non-rbac.jsonnet

@@ -202,6 +202,20 @@ local runtime_images ='[
     ],
     "depName": "pom.xml",
     "fileNameSuffix": ".java"
+  },
+  {
+     "ID": "ballerina",
+     "compiled": true,
+     "versions": [
+       {
+          "name": "ballerina0.970.1",
+          "version": "0.970.1",
+          "runtimeImage": "kubeless/ballerina@sha256:b1f4f0cb65258d3035ae9eec2ae37a7c0d7e4eac6b150da5fb7933668114a409",
+          "initImage": "kubeless/ballerina-init@sha256:5acecccb9d05d298606c8514ee16b25bab76e4a2f35eda30601bb7f229e01cfd"
+       }
+     ],
+     "depName": "",
+     "fileNameSuffix": ".bal"
   }
 ]';
 

pkg/langruntime/langruntime.go

@@ -240,6 +240,8 @@ func (l *Langruntimes) GetBuildContainer(runtime, depsChecksum string, env []v1.
 	case strings.Contains(runtime, "java"):
 		command = appendToCommand(command,
 			"mv /kubeless/pom.xml /kubeless/function-pom.xml")
+	case strings.Contains(runtime, "ballerina"):
+		return v1.Container{}, fmt.Errorf("Ballerina does not require a dependencies file")
 	}
 
 	return v1.Container{
@@ -311,6 +313,17 @@ func (l *Langruntimes) GetCompilationContainer(runtime, funcName string, install
 			"mvn package > /dev/termination-log 2>&1 && mvn install > /dev/termination-log 2>&1"
 	case strings.Contains(runtime, "dotnetcore"):
 		command = "/app/compile-function.sh " + installVolume.MountPath
+	case strings.Contains(runtime, "ballerina"):
+		command = fmt.Sprintf(
+			"mkdir -p /kubeless/kubeless/ /kubeless/func/ && "+
+				"cp -r /ballerina/files/kubeless/*.bal /kubeless/kubeless/ && "+
+				"cp -r /kubeless/*.bal /kubeless/func/ && "+
+				"touch /kubeless/kubeless.toml && "+
+				"cp -r /ballerina/files/src/kubeless_run.tpl.bal /kubeless/ && "+
+				"sed 's/<<FUNCTION>>/%s/g' /kubeless/kubeless_run.tpl.bal > /kubeless/kubeless_run.bal && "+
+				"rm /kubeless/kubeless_run.tpl.bal && "+
+				"ballerina build kubeless_run.bal ", funcName)
+
 	default:
 		return v1.Container{}, fmt.Errorf("Not found a valid compilation step for %s", runtime)
 	}