freeze doc - mv js code samples to includes

content/code_samples/freeze/set-individual-freeze.js

@@ -0,0 +1,57 @@
+const {RippleAPI} = require('ripple-lib');
+
+const api = new RippleAPI({
+  server: 'wss://s1.ripple.com' // Public rippled server
+});
+api.on('error', (errorCode, errorMessage) => {
+  console.log(errorCode + ': ' + errorMessage);
+});
+
+const issuing_address = 'rf1BiGeXwwQoi8Z2ueFYTEXSwuJYfV2Jpn';
+const issuing_secret = 's████████████████████████████';
+    // Best practice: get your secret from an encrypted
+    //  config file instead
+const address_to_freeze = 'rUpy3eEg8rqjqfUoLeBnZkscbKbFsKXC3v';
+const currency_to_freeze = 'USD';
+
+api.connect().then(() => {
+
+  // Look up current state of trust line
+  const options = {counterparty: address_to_freeze,
+                 currency: currency_to_freeze};
+  console.log('looking up', currency_to_freeze, 'trust line from',
+              issuing_address, 'to', address_to_freeze);
+  return api.getTrustlines(issuing_address, options);
+
+}).then(data => {
+
+  // Prepare a trustline transaction to enable freeze
+  let trustline = {};
+  if (data.length !== 1) {
+    console.log('trustline not found, making a default one');
+    trustline = {
+      currency: currency_to_freeze,
+      counterparty: address_to_freeze,
+      limit: 0
+    };
+  } else {
+    trustline = data[0].specification;
+    console.log('trustline found. previous state:', trustline);
+  }
+
+  trustline.frozen = true;
+
+  console.log('preparing trustline transaction for line:', trustline);
+  return api.prepareTrustline(issuing_address, trustline);
+
+}).then(prepared_tx => {
+
+  // Sign and submit the trustline transaction
+  console.log('signing tx:', prepared_tx.txJSON);
+  const signed1 = api.sign(prepared_tx.txJSON, issuing_secret);
+  console.log('submitting tx:', signed1.id);
+
+  return api.submit(signed1.signedTransaction);
+}).then(() => {
+  return api.disconnect();
+}).catch(console.error);