--- title: "[WIZwiki_W7500ECO] HTTPClient with JSON parser" url: "https://maker.wiznet.io/WIZnet/projects/%5Bwizwiki-w7500eco%5D-httpclient-with-json-parser/" markdown_url: "https://maker.wiznet.io/WIZnet/projects/%5Bwizwiki-w7500eco%5D-httpclient-with-json-parser/md" type: "UCC: User Created Content" author: "Soohwan Kim" author_url: "https://www.hackster.io/embeddist/wizwiki-w7500eco-httpclient-with-json-parser-f96641" editor: "WIZnet" editor_url: "https://maker.wiznet.io/" original_author: "Soohwan Kim" original_url: "https://www.hackster.io/embeddist/wizwiki-w7500eco-httpclient-with-json-parser-f96641" published: "2023-04-03" language: "en" likes: 0 views: 100 comments: 0 source: "WIZnet Makers (https://maker.wiznet.io/)" --- # [WIZwiki_W7500ECO] HTTPClient with JSON parser > This post shows how to use HTTPClient parse Json data in ARMmbed platform. Original author: Soohwan Kim (source: https://www.hackster.io/embeddist/wizwiki-w7500eco-httpclient-with-json-parser-f96641) ## Article **DETAILSDescription** This post shows how to use HTTPClient parse Json data in ARMmbed platform. ![\[WIZwiki_W7500ECO\] HTTPClient with JSON parser](https://hackster.imgix.net/uploads/cover_image/file/87929/21948839603_0d8306cc39_n.jpg?auto=compress%2Cformat&w=900&h=675&fit=min) **Components Required** - Wizwiki W7500 ECO ## **Story** JSON is easy for machines to parse and generate which is based on a subset of the JavaScript Programming Language. Currently many Web Services allow to access data in JSON format. However, JSON parser is too big for low-end device as like a ARMmbed platform which has limited-resource. This post shows how to use HTTPClient parse Json data in ARMmbed platform. ![](https://hackster.imgix.net/uploads/image/file/87899/21948839603_0d8306cc39_n.jpg?auto=compress%2Cformat&w=740&h=555&fit=max) ### ** Preparation materials** 1. Software - JSON Parser: [MbedJSONValue libs](http://mbed.org/users/samux/code/MbedJSONValue/) - Ethernet Networking : [WIZnetInterface](https://developer.mbed.org/teams/WIZnet/code/WIZnetInterface/) - HTTP Server with JSON : [Fraka6 Blog – No Free Lunch: The simplest python server example ![😉](https://s.w.org/images/core/emoji/11.2.0/svg/1f609.svg)](https://bitbucket.org/fraka6/mlboost/src/ce9e76218daa7bec96d61b98c9a9e90b10440b7c/mlboost/examples/server.py) Hardware WIZwiki-W7500ECONET: WIZwiki-W7500 + ECO Shield Ethernet ![](https://hackster.imgix.net/uploads/image/file/87900/22570039655_dd7e08b859_n.jpg?auto=compress%2Cformat&w=740&h=555&fit=max) ARMmbed Board: [WIZwiki-W7500ECO](http://wizwiki.net/wiki/doku.php?id=products:wizwiki-w7500eco:start) ![](https://hackster.imgix.net/uploads/image/file/87901/22556470552_bcb48984ec_n.jpg?auto=compress%2Cformat&w=740&h=555&fit=max) Ethernet Shield: [ECO Shield Ethernet](http://wizwiki.net/wiki/doku.php?id=products:wizwiki-w7500eco:eco-shield#eco_shield_ethernet) ![](https://hackster.imgix.net/uploads/image/file/87902/21947481954_e8193f30cb_n.jpg?auto=compress%2Cformat&w=740&h=555&fit=max) ### ** Simplest python JSON server on PC** Modify Server IP address & port on ron_handler ``` def run(port=8000): #set port print('http server is starting...') #ip and port of server #server_address = ('127.0.0.1', port) server_address = ('192.168.0.223', port)#set port httpd = HTTPServer(server_address, Handler) print('http server is running...listening on port %s' %port) httpd.serve_forever() ``` Modify JSON form in do_GET handler ``` #handle GET command def do_GET(self): if format == 'html': self.send_response(200) self.send_header("Content-type", "text/plain") self.send_header('Content-type','text-html') self.end_headers() self.wfile.write("body") elif format == 'json': #self.request.sendall(json.dumps({'path':self.path})) #self.request.sendall(json.dumps({'pi':3.14})) self.request.sendall(json.dumps({'name':'John snow', 'age': 30, 'gender':'male'})) else: self.request.sendall("%st%s" %('path', self.path)) return ``` Execute json_server Excute json_server ![](https://hackster.imgix.net/uploads/image/file/87903/22570506275_5aaffdfe91_b.jpg?auto=compress%2Cformat&w=740&h=555&fit=max) Test by using curl ```plaintext $>curl ip_address:port_number ``` ![](https://hackster.imgix.net/uploads/image/file/87904/22557012682_d434b65e5f_z.jpg?auto=compress%2Cformat&w=740&h=555&fit=max) ### ** Make main.cc** - Source Code@ Network Configration for WIZwiki-W7500ECO ```plaintext // Enter a MAC address for your controller below. uint8_t mac_addr[6] = {0x00, 0x08, 0xDC, 0x00, 0x01, 0x02}; printf("initializing Ethernetrn"); // initializing MAC address eth.init(mac_addr, "192.168.0.34", "255.255.255.0", "192.168.0.1"); // Check Ethenret Link if(eth.link() == true) printf("- Ethernet PHY Link-Done rn"); else printf("- Ethernet PHY Link- Failrn"); // Start Ethernet connecting: Trying to get an IP address using DHCP if (eth.connect()<0) printf("Fail - Ethernet Connecing"); ``` TCP connect to simple python JSON server ```plaintext sock.connect("192.168.0.223", 8000); // "destination IP address", destination port number ``` Make Get form in HTTP format ```plaintext snprintf(http_tx_msg, http_tx_msg_sz, "GET / HTTP/1.1rnHost: 192.168.0.223:8000rnUser-Agent: WIZwiki-W7500ECOrnConection: closernrn"); ``` TCP Send Get form ```plaintext sock.send_all(http_tx_msg, http_tx_msg_sz-1); // tx_buf, tx_buf_size ``` TCP Recv data in JSON format ```plaintext while ( (returnCode = sock.receive(http_rx_msg, http_rx_msg_sz-1)) > 0) { http_rx_msg[returnCode] = ''; printf("Received %d chars from server:nr%sn", returnCode, http_rx_msg); } ``` 1. Do JSON parse ```plaintext parse(parser, http_rx_msg); ``` 1. Output the parsed data ```plaintext // parsing "string" in string type printf("name =%srn" , parser["name"].get().c_str()); // parsing "age" in integer type printf("age =%drn" , parser["age"].get()); // parsing "gender" in string type printf("gender =%srn" , parser["gender"].get().c_str()); ``` ### ** Demo. HTTPClient with JSON parser** 1. 1. Network config. 2. Confirm Received JSON data 3. Print-out the pasing data ![](https://hackster.imgix.net/uploads/image/file/87905/22557404802_8bfb5be6a2_c.jpg?auto=compress%2Cformat&w=740&h=555&fit=max) ### ** Packet Capture** 1. 1. TCP-Connection 2. Target board sends GET Form to simple python JSON server 3. simple python JSON server sends JSON data to Target board ![](https://hackster.imgix.net/uploads/image/file/87906/22545387906_f80e69cab6_b.jpg?auto=compress%2Cformat&w=740&h=555&fit=max) --- Source: https://maker.wiznet.io/WIZnet/projects/%5Bwizwiki-w7500eco%5D-httpclient-with-json-parser/