[JAVA] Get Salesforce data using REST API

Introduction

• (Although it is an article on Mac environment, the procedure is the same for Windows environment. Please read and try the environment-dependent part.) *

After reading this article to the end, you will be able to:

--Set up Salesforce API (enable OAuth settings) --Get Salesforce data with Python, Java, Shell Script --Implementing REST web services in Salesforce Apex

Sample code

python_sfdc_get_user.py

sf = Salesforce(username=USERNAME, password=PASSWORD,
                security_token=SECURITY_TOKEN, sandbox=False)
res = sf.query(
    'SELECT Id, Name, LastLoginDate FROM User WHERE Name =\'nsuhara\'')
print(json.dumps(res, indent=4))

Execution result

python_result.json

{
    "totalSize": 1,
    "done": true,
    "records": [
        {
            "attributes": {
                "type": "User",
                "url": "/services/data/v38.0/sobjects/User/0056F000006StK9QAK"
            },
            "Id": "0056F000006StK9QAK",
            "Name": "nsuhara",
            "LastLoginDate": "2019-05-18T13:07:00.000+0000"
        }
    ]
}

Related articles

-SFDC REST API Developer's Guide

Execution environment

Source code

I think that understanding will deepen if you read while actually following the implementation contents and source code. Please use it by all means.

GitHub

Advance preparation

Salesforce OAuth settings

Settings> Create> Applications> Connected Applications> Click New

`Please wait 2-10 minutes for the changes to take effect on the server before using the connected application. ``

Parameter overview

** (Reference 1) **

** (Ref 2) **

Security tokens can be reissued from My Settings> Personal> Reset My Security Talk.

Shell Script sample

shell_script_sfdc_get_user.sh

#!/bin/sh

export HOST='<Parameter reference>'
export CLIENT_ID='<Parameter reference>'
export CLIENT_SECRET='<Parameter reference>'
export USERNAME='<Parameter reference>'
export PASSWORD_AND_SECURITY_TOKEN='<Parameter reference>'

export INSTANCE_URL=`curl -s https://$HOST/services/oauth2/token -d "grant_type=password" -d "client_id=$CLIENT_ID" -d "client_secret=$CLIENT_SECRET" -d "username=$USERNAME" -d "password=$PASSWORD_AND_SECURITY_TOKEN" | awk 'BEGIN{FS="instance_url\":"}{print $2}' | awk 'BEGIN{FS=","}{print $1}' | sed -e 's/\"//g'`
export ACCESS_TOKEN=`curl -s https://$HOST/services/oauth2/token -d "grant_type=password" -d "client_id=$CLIENT_ID" -d "client_secret=$CLIENT_SECRET" -d "username=$USERNAME" -d "password=$PASSWORD_AND_SECURITY_TOKEN" | awk 'BEGIN{FS="access_token\":"}{print $2}' | awk 'BEGIN{FS=","}{print $1}' | sed -e 's/\"//g'`

export SOQL="SELECT+Id,Name,LastLoginDate+FROM+User+WHERE+Name='nsuhara'"

curl $INSTANCE_URL/services/data/v45.0/query?q=$SOQL -H "Authorization: OAuth $ACCESS_TOKEN" -H "X-PrettyPrint:1"

shell_script_result.json

{
    "totalSize": 1,
    "done": true,
    "records": [
        {
            "attributes": {
                "type": "User",
                "url": "/services/data/v45.0/sobjects/User/0056F000006StK9QAK"
            },
            "Id": "0056F000006StK9QAK",
            "Name": "nsuhara",
            "LastLoginDate": "2019-05-18T14:04:05.000+0000"
        }
    ]
}

Python sample

python_sfdc_get_user.py

import json

from simple_salesforce import Salesforce

USERNAME = '<Parameter reference>'
PASSWORD = '<Parameter reference>'
SECURITY_TOKEN = '<Parameter reference>'


def main():
    sf = Salesforce(username=USERNAME, password=PASSWORD,
                    security_token=SECURITY_TOKEN, sandbox=False)
    res = sf.query(
        'SELECT Id, Name, LastLoginDate FROM User WHERE Name =\'nsuhara\'')
    print(json.dumps(res, indent=4))


if __name__ == '__main__':
    main()

python_result.json

{
    "totalSize": 1,
    "done": true,
    "records": [
        {
            "attributes": {
                "type": "User",
                "url": "/services/data/v38.0/sobjects/User/0056F000006StK9QAK"
            },
            "Id": "0056F000006StK9QAK",
            "Name": "nsuhara",
            "LastLoginDate": "2019-05-18T14:06:19.000+0000"
        }
    ]
}

Java sample

java_App.java

package rest_api;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.utils.URIBuilder;
import org.apache.http.Header;
import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.impl.client.HttpClientBuilder;
import org.apache.http.message.BasicHeader;
import org.apache.http.util.EntityUtils;
import org.json.JSONException;
import org.json.JSONObject;
import org.json.JSONTokener;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;

public class App {
    static final String HOST = "<Parameter reference>";
    static final String CLIENT_ID = "<Parameter reference>";
    static final String CLIENT_SECRET = "<Parameter reference>";
    static final String USERNAME = "<Parameter reference>";
    static final String PASSWORD_AND_SECURITY_TOKEN = "<Parameter reference>";

    static final String GRANT_SERVICE = "/services/oauth2/token?grant_type=password";

    public static void main(String[] args) {
        String UA = "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.131 Safari/537.36";
        List<Header> headers = new ArrayList<Header>();
        headers.add(new BasicHeader("User-Agent", UA));

        HttpClient httpClient = HttpClientBuilder.create().setDefaultHeaders(headers).build();

        String loginURL = "https://" + HOST + GRANT_SERVICE + "&client_id=" + CLIENT_ID + "&client_secret="
                + CLIENT_SECRET + "&username=" + USERNAME + "&password=" + PASSWORD_AND_SECURITY_TOKEN;

        HttpPost httpPost = new HttpPost(loginURL);
        HttpResponse response = null;

        try {
            response = httpClient.execute(httpPost);
        } catch (ClientProtocolException cpException) {
            // Handle protocol exception
        } catch (IOException ioException) {
            // Handle system IO exception
        }

        final int statusCode = response.getStatusLine().getStatusCode();
        if (statusCode != HttpStatus.SC_OK) {
            System.out.println("Error authenticating to Force.com: " + statusCode);
            // Error is in EntityUtils.toString(response.getEntity())
            return;
        }

        String getResult = null;
        try {
            getResult = EntityUtils.toString(response.getEntity());
        } catch (IOException ioException) {
            // Handle system IO exception
        }

        JSONObject jsonObject = null;
        String loginAccessToken = null;
        String loginInstanceUrl = null;

        try {
            jsonObject = (JSONObject) new JSONTokener(getResult).nextValue();
            loginInstanceUrl = jsonObject.getString("instance_url");
            loginAccessToken = jsonObject.getString("access_token");
        } catch (JSONException jsonException) {
            // Handle JSON exception
        }

        System.out.println(response.getStatusLine());

        httpPost.releaseConnection();
        try {
            final URIBuilder builder = new URIBuilder(loginInstanceUrl);
            final String SOQL = "SELECT Id, Name, LastLoginDate FROM User WHERE Name = \'nsuhara\'";
            builder.setPath("/services/data/v45.0/query/").setParameter("q", SOQL);
            final HttpGet get = new HttpGet(builder.build());
            get.setHeader("Authorization", "Bearer " + loginAccessToken);

            final HttpResponse queryResponse = httpClient.execute(get);

            ObjectMapper mapper = new ObjectMapper();
            final JsonNode queryResults = mapper.readValue(queryResponse.getEntity().getContent(), JsonNode.class);

            System.out.println("queryResults:" + queryResults);
        } catch (Exception e) {
            // Handle exception
        }
    }
}

java_result.json

{
    "totalSize": 1,
    "done": true,
    "records": [
        {
            "attributes": {
                "type": "User",
                "url": "/services/data/v45.0/sobjects/User/0056F000006StK9QAK"
            },
            "Id": "0056F000006StK9QAK",
            "Name": "nsuhara",
            "LastLoginDate": "2019-05-18T14:09:31.000+0000"
        }
    ]
}

REST Web Service Implementation Sample

Apex implementation

apex_SampleRestApi.cls

@RestResource(urlMapping='/sample/restapi/*')
global without sharing class SampleRestApi {
	@HttpGet
	global static List<User> getUsers() {
		return [SELECT Id, Name, LastLoginDate FROM User WHERE Name = 'nsuhara' LIMIT 1];
	}
}

Enable Apex REST service

Settings> Manage Users> Privilege Set (or Profile)> Edit System Privileges

Enable Apex class access

Settings> Manage Users> Permission Set (or Profile)> Edit Apex Class Access`

HTTP method GET test

python_requests_sfdc.py

import requests

HOST = '<Parameter reference>'
CLIENT_ID = '<Parameter reference>'
CLIENT_SECRET = '<Parameter reference>'
USERNAME = '<Parameter reference>'
PASSWORD_AND_SECURITY_TOKEN = '<Parameter reference>'


def main():
    params = {
        'grant_type': 'password',
        'client_id': CLIENT_ID,
        'client_secret': CLIENT_SECRET,
        'username': USERNAME,
        'password': PASSWORD_AND_SECURITY_TOKEN
    }

    res_post = requests.post(
        'https://{}/services/oauth2/token'.format(HOST), params=params)

    access_token = res_post.json().get('access_token')
    instance_url = res_post.json().get('instance_url')
    services_url = '/services/apexrest/sample/restapi'
    headers = {
        'Content-type': 'application/json',
        'Accept-Encoding': 'gzip',
        'Authorization': 'Bearer {}'.format(access_token)
    }

    res_get = requests.request(method='get', url=instance_url+services_url,
                               headers=headers, params={'xxx': 'yyy'}, timeout=10)

    print(res_get.status_code)
    print(res_get.json())


if __name__ == '__main__':
    main()

python_result.json

[
    {
        "attributes": {
            "type": "User",
            "url": "/services/data/v45.0/sobjects/User/0056F000006StK9QAK"
        },
        "Id": "0056F000006StK9QAK",
        "Name": "nsuhara",
        "LastLoginDate": "2019-05-18T14: 11: 22.000+0000"
    }
]

Summary-Examination of implementation model

Consider the implementation model based on the environment and conditions