Project Flogo provides a CLI that gives you the ability to build flogo applications (flows, streams, rules, microgateway). With this tool you can, among other things, create your applications, build applications and install new extensions. This tool is great to use with Continuous Integration and Continuous Deployment tools like Jenkins and Travis-CI.
In this tutorial you will learn how to use the flogo cli.
This demo makes use of the Flogo CLI. If you don’t have that one running yet, please check out Getting Started with the Flogo CLI
If you have any questions, feel free to post an issue on GitHub and tag it as a question or chat with the team and community:
Flogo apps are constructed using a JSON file called flogo.json. You can create those files using the Flogo Web UI, or you can create them manually. Now let’s create the flogo.json file. To do that, execute touch flogo.json in a terminal (or open up a new file in your text editor), which will create a new empty file for you.
Now you can copy the contents below to the newly created flogo.json file. The Flogo app has a REST trigger which listens on port 9233 and the HTTP path /test/:name (where :name is a parameter you can fill in).
{
"name": "SampleApp",
"type": "flogo:app",
"version": "0.0.1",
"appModel": "1.1.0",
"description": "",
"imports": [
"github.com/project-flogo/contrib/activity/log",
"github.com/project-flogo/contrib/trigger/rest",
"github.com/project-flogo/flow"
],
"triggers": [
{
"id": "receive_http_message",
"ref": "#rest",
"name": "Receive HTTP Message",
"description": "Simple REST Trigger",
"settings": {
"port": 8080
},
"handlers": [
{
"settings": {
"method": "GET",
"path": "/test"
},
"action": {
"ref": "#flow",
"settings": {
"flowURI": "res://flow:get_name"
},
"input": {
},
"output": {
"code": 200
}
}
}
]
}
],
"resources": [
{
"id": "flow:get_name",
"data": {
"name": "GetName",
"metadata": {
"input": [
{
"name": "name",
"type": "string"
}
],
"output": [
{
"name": "greeting",
"type": "string"
}
]
},
"tasks": [
{
"id": "log_2",
"name": "Log",
"description": "Logs a message",
"activity": {
"ref": "#log",
"input": {
"message": "Hello from Flogo",
"addDetails": false
}
}
}
]
}
}
]
}
To create the source code simply execute flogo create -f flogo.json myapp. This tells the Flogo CLI to take the flogo.json file and create the source for the app in a folder called myapp. It will also download a few Go packages that the app will need. The output will look something like:
flogo create -f /Users/mellis/Downloads/sample_app_1.json myapp
Creating Flogo App: myapp
Installing: github.com/project-flogo/core@latest
Installed trigger: github.com/project-flogo/contrib/trigger/rest
Installed action: github.com/project-flogo/flow
Installed activity: github.com/project-flogo/contrib/activity/log
The next step is to build the executable and for that we need to be in the directory myapp (cd myapp). To build a flogo app from the source you can execute the command flogo build -e, which tells the flogo cli to build the app (and place it in a bin directory) and embed all configuration into a single executable
You have just built the Flogo app, so now you can test it. From the bin directory (cd bin) you can run ./myapp which will start the app. In the terminal you’ll see something like
2018-05-12 04:34:56.434 INFO [engine] - Engine Starting...
2018-05-12 04:34:56.435 INFO [engine] - Starting Services...
2018-05-12 04:34:56.435 INFO [engine] - Started Services
2018-05-12 04:34:56.435 INFO [engine] - Starting Triggers...
2018-05-12 04:34:56.435 INFO [engine] - Trigger [ receive_http_message ]: Started
2018-05-12 04:34:56.435 INFO [engine] - Triggers Started
2018-05-12 04:34:56.435 INFO [engine] - Engine Started
To test it we’ll use the curl command line tool, which is installed on most Operating Systems. From a new terminal window execute the command curl http://localhost:8080/test. It will send an HTTP request to the app on port 8080 (which was configured in the flogo.json file). In the first terminal you will see the result of the flow (Hello from Flogo), you’ll also see there are additional lines in your window that indicate a flow has been executed.
2019-05-13T17:40:14.851+0200 INFO [flogo.engine] - Starting app [ SampleApp ] with version [ 0.0.1 ]
2019-05-13T17:40:14.851+0200 INFO [flogo.engine] - Engine Starting...
2019-05-13T17:40:14.851+0200 INFO [flogo.engine] - Starting Services...
2019-05-13T17:40:14.851+0200 INFO [flogo] - ActionRunner Service: Started
2019-05-13T17:40:14.851+0200 INFO [flogo.engine] - Started Services
2019-05-13T17:40:14.851+0200 INFO [flogo.engine] - Starting Application...
2019-05-13T17:40:14.851+0200 INFO [flogo] - Starting Triggers...
2019-05-13T17:40:14.851+0200 INFO [flogo] - Trigger [ receive_http_message ]: Started
2019-05-13T17:40:14.851+0200 INFO [flogo] - Triggers Started
2019-05-13T17:40:14.851+0200 INFO [flogo.engine] - Application Started
2019-05-13T17:40:14.851+0200 INFO [flogo.engine] - Engine Started
2019-05-13T17:40:14.851+0200 INFO [flogo] - Listening on http://0.0.0.0:8080
2019-05-13T17:40:33.456+0200 INFO [flogo.activity.log] - Hello from Flogo
2019-05-13T17:40:33.456+0200 INFO [flogo.flow] - Instance [28ac8005732b92373635a219624031dd] Done