samples/twitter-sentiment-processor/demos/demo1/provider/app.js

71 lines
2.0 KiB
JavaScript

const express = require('express');
const bodyParser = require('body-parser');
require('isomorphic-fetch');
// express
const app = express();
app.use(bodyParser.json());
const port = 3001;
// dapr
const daprPort = process.env.DAPR_HTTP_PORT || "3500";
const stateEndpoint = `http://localhost:${daprPort}/v1.0/state/tweet-store`;
// store state
var saveContent = function(obj) {
return new Promise(
function(resolve, reject) {
if (!obj || !obj.id) {
reject({message: "invalid content"});
return;
}
const state = [{ key: obj.id, value: obj }];
fetch(stateEndpoint, {
method: "POST",
body: JSON.stringify(state),
headers: { "Content-Type": "application/json" }
}).then((_res) => {
if (!_res.ok) {
console.log(_res.statusText);
reject({message: "error saving content"});
}else{
resolve(obj)
}
}).catch((error) => {
reject({message: error});
});
}
);
};
// tweets handler
app.post('/tweets', (req, res) => {
const tweet = req.body;
if (!tweet) {
res.status(400).send({error: "invalid content"});
return;
}
let obj = {
id: tweet.id_str,
author: tweet.user.screen_name,
author_pic: tweet.user.profile_image_url_https,
content: tweet.full_text || tweet.text, // if extended then use it
lang: tweet.lang,
published: tweet.created_at,
sentiment: 0.5 // default to neutral sentiment
};
saveContent(obj)
.then(function(fulfilled) {
console.log(fulfilled);
res.status(200).send({});
})
.catch(function (error) {
console.log(error.message);
res.status(500).send(error);
});
});
app.listen(port, () => console.log(`Port: ${port}!`));