How to consume API which is created in nodejs-express-oracledb - node.js

Question

I would want to consume GET/PUT/POST/DELETE API’s through a web page (HTML) which would be integrated on the Oracle JET.
The webpage will have one input free text option, where the user can type in to update the record.
i.e. If I click on one record on the JET dashboard, the API ‘GET /alluser/:FIRST_NAME – Read the profile of an user’ will be called,
it will display the detailed record with one text box as free text,
once the user enters text and hits submit, ‘PUT /process_post – Update the profile of an user’ API will be called, which will update the record.
Here is my script
var express = require('express');
var oracledb = require('oracledb');
var app = express();
var dbConfig = require('./dbconfig.js');
var bodyParser = require('body-parser');
var port = 3000;
app.use(bodyParser.json()); // Use body parser to parse JSON body
oracledb.outFormat = oracledb.OBJECT;
// Get a non-pooled connection
function run() {
oracledb.createPool({
user : dbConfig.user,
password : dbConfig.password,
connectString : dbConfig.connectString
},
function(err) {
if (err)
console.error("createPool() error: " + err.message);
else
var server = app.listen(port,
function () {
console.log('Server is listening on port ' + server.address().port);
});
});
}
function doGetConnection(res, cb) {
oracledb.getConnection(function (err, connection) {
if (err) {
res.set('Content-Type', 'application/json');
res.status(500).send(JSON.stringify({
status: 500,
message: "Error getting DB connection",
detailed_message: err.message
}));
} else {
cb(err, connection);
console.log(" Connection is connected");
}
});
}
app.post('/process_post', function (req, res) {
console.log("contenttype"+req.get('Content-Type'))
doGetConnection(res, function(err, connection) {
if (err)
return;
connection.execute(
"INSERT INTO TEST_TABLE(FIRST_NAME,LAST_NAME) VALUES (:FIRST_NAME,:LAST_NAME)",
[(req.body.FIRST_NAME),(req.body.LAST_NAME) ],
{ autoCommit: true,
outFormat:oracledb.OBJECT
},
console.log("check2"),
function (err) {
console.log("check3");
if (err) {
console.log("check4");
res.set('Content-Type', 'application/json');
res.status(400).send(JSON.stringify({
status: 400,
message: "Input Error",
detailed_message: err.message
}));
} else {
// Successfully created the resource
res.status(201).set('Location', '/process_post/' + req.body.FIRST_NAME).end();
}
doRelease(connection, "POST /process_post");
});
});
});
app.get('/alluser', function (req, res) {
doGetConnection(res, function(err, connection) {
if (err)
return;
connection.execute(
"SELECT * from employees",
function (err, result) {
if (err) {
res.set('Content-Type', 'application/json');
res.status(500).send(JSON.stringify({
status: 500,
message: "Error getting the farmer's profile",
detailed_message: err.message
}));
} else {
res.contentType('application/json').status(200);
res.send(JSON.stringify(result.rows));
}
doRelease(connection, "GET /bananas");
});
});
});
app.get('/alluser/:FIRST_NAME', function (req, res) {
doGetConnection(res, function(err, connection) {
if (err)
return;
connection.execute(
"SELECT * from employees WHERE first_name = :f",
{ f: req.params.FIRST_NAME },
function (err, result) {
if (err) {
res.set('Content-Type', 'application/json');
res.status(500).send(JSON.stringify({
status: 500,
message: "Error getting the farmer's profile",
detailed_message: err.message
}));
} else if (result.rows.length < 1) {
res.set('Content-Type', 'application/json');
res.status(404).send(JSON.stringify({
status: 404,
message: "FIRST_NAME doesn't exist",
detailed_message: ""
}));
} else {
res.contentType('application/json');
res.status(200).send(JSON.stringify(result.rows));
}
doRelease(connection, "GET /user/" + req.params.FIRST_NAME);
});
});
});
function doRelease(connection, message) {
connection.close(
function(err) {
if (err)
console.error(err);
else
console.log(message + " : Connection released");
});
}
run();
Thank you.

Answer 1

Oracle JET can help you make API calls.
Here's an example from their Cookbook: http://www.oracle.com/webfolder/technetwork/jet/jetCookbook.html?component=crud&demo=model
Have a look at the documentation for Collection and Model.
It's a lot to read if you're getting into it for the first time, so I'll give a quick example for a GET all:
var dataModel = oj.Model.extend({urlRoot: 'example.com'});
var modelInstance = new dataModel();
var CollectionConfig = {
model: modelInstance,
url: 'example.com'
};
var dataCollection = oj.Collection.extend(CollectionConfig);
var collectionInstance = new dataCollection();
collectionInstance.fetch({
success: function (collection, response, options) {
console.log(response);
},
error: function (jqXHR, textStatus, errorThrown) {
console.log(errorThrown);
}
});