Public

  • Everyone can read it

  • @TheChannel

Private

  • need the id

  • -100xxxxxxxx

Exercice 1

Create a private Channel

Create a micronaut cli to send a "hello world" to it

$ mn
mn> create-cli-app mn-hello-world
build.gradle
implementation group: 'com.puravida.telegram', name: 'mn-telegram-api', version: '0.1.9'
MnHelloWorldCommand.java
Add an @Option channelId argument

@Inject TelegramBot

Construct a new Message and send it

Build and execute (don't forget your telegram.token variable)

(see exercises/mn-hello-world project)

Exercice 2

Send the Picture of the Day from NASA to the channel

$ mn
mn> create-cli-app mn-nasa
build.gradle
implementation "io.micronaut:micronaut-http-client"
implementation group: 'com.puravida.telegram', name: 'mn-telegram-api', version: '0.1.9'
implementation group: 'com.jayway.jsonpath', name: 'json-path', version: '2.4.0'
implementation group: 'commons-io', name: 'commons-io', version: '2.6'
MnNasaCommand.java
Add an @Option channelId argument

@Inject TelegramBot

Parse the JSON

    String nasaURL = "https://api.nasa.gov/planetary/apod?api_key=DEMO_KEY";
    String nasaJSON = org.apache.commons.io.IOUtils.toString(new java.net.URL(nasaURL));
    Object document = Configuration.defaultConfiguration().jsonProvider().parse(nasaJSON);

    String title = JsonPath.read(document, "$.title");
    String explanation = JsonPath.read(document, "$.explanation");
    String imageURL  = JsonPath.read(document, "$.url");


Construct a new Message and send the title and the explanation
Construct a SendPhoto to send the bytes of the image

Build and execute (don't forget your telegram.token variable)

(see exercises/mn-nasa project)

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