🚀🚀🚀

Author: ToQoz

.gitignore

@@ -0,0 +1,2 @@
+node_modules
+npm-debug.log

.npmignore

@@ -0,0 +1,3 @@
+/examples
+/misc
+/web

LICENSE

@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2015 Takatoshi Matsumoto
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -0,0 +1,48 @@
+# api-gateway-mapping-template
+
+make AWS API Gateway's Mapping Template testable
+
+![Image](http://toqoz.net/art/api-gateway-mapping-template.png)
+
+## Installation
+
+```
+npm install api-gateway-mapping-template
+```
+
+## Examples
+
+See [./examples](/examples)
+
+## API
+
+```node
+var mappingTemplate = require('api-gateway-mapping-template')
+```
+
+### mappingTemplate(template, payload, params, context)
+
+This function renders AWS API Gateway's Mapping Template by using given payload, params and context.
+
+- Arguments
+  - template - **required** - `String|Buffer`
+  - payload - **required** - `String|Buffer`
+  - params - `map`
+    - path - `map<String, String|Number|Boolean|null>`
+    - querystring - `map<String, String|Number|Boolean|null>`
+    - header - `map<String, String|Number|Boolean|null>`
+  - context - `map`
+    - indentity - `map<String, String>`
+      - cognitoAuthenticationType - `String`
+      - cognitoIdentityId - `String`
+      - cognitoIdentityPoolId - `String`
+      - sourceIp - `String`
+      - user - `String`
+      - userAgent - `String`
+      - userArn - `String`
+    - requestId - `String`
+    - resourceId - `String`
+    - resourcePath -  `String`
+    - stage -  `String`
+- Return value
+  - rendered template -  `String`

examples/express/README.md

@@ -0,0 +1,4 @@
+# Express + Mapping Template
+
+1. run server `node app.js`
+2. request `curl -X POST -d 'aaa=bbb' 'http://localhost:3000'`

examples/express/app.js

@@ -0,0 +1,28 @@
+var fs = require('fs');
+
+var express = require('express');
+var app = express();
+// enable to get request body in a handler...
+app.use(function(req, res, next) {
+  req.rawBody = '';
+  req.setEncoding('utf8');
+  req.on('data', function(chunk) { req.rawBody += chunk; });
+  req.on('end', function() { next(); });
+});
+
+var mappingTemplate = require("../..");
+
+app.post("/", function(req, res) {
+  fs.readFile(__dirname + "/mapping_template.vtl", function(err, data) {
+    var template = data.toString();
+    var payload = req.rawBody;
+    var params = {header: req.headers, path: req.params, querystring: req.query};
+
+    var json = mappingTemplate(template, payload, params);
+    var event = JSON.parse(json);
+
+    require("./lambda").handler(event, {succeed: res.send.bind(res)});
+  });
+});
+
+app.listen(3000);

examples/express/lambda.js

@@ -0,0 +1,21 @@
+exports.handler = function(event, context) {
+  var response = "--- HEADERS ---\n";
+
+  Object.keys(event.headers).forEach(function(k) {
+    response += k + " = " + event.headers[k] + "\n";
+  });
+
+  response += "\n--- QUERYSTRINGS ---\n";
+
+  Object.keys(event.querystring).forEach(function(k) {
+    response += k + " = " + event.querystring[k] + "\n";
+  });
+
+  response += "\n--- FORM VALUES ---\n";
+
+  Object.keys(event.form).forEach(function(k) {
+    response += k + " = " + event.form[k] + "\n";
+  });
+
+  context.succeed(response);
+};

examples/express/mapping_template.vtl

@@ -0,0 +1,19 @@
+{
+  "headers": {
+#foreach($key in $input.params().header.keySet())
+    "$key": "$input.params().header.get($key)"#if($foreach.hasNext), #end
+#end
+  },
+  "querystring": {
+#foreach($key in $input.params().querystring.keySet())
+    "$key": "$input.params().querystring.get($key)"#if($foreach.hasNext), #end
+#end
+  },
+  "form": {
+#set($form = $input.path('$').split('&'))
+#foreach($kvString in $form)
+  #set($kv = $kvString.split('='))
+  "$kv[0]": "$util.urlDecode($kv[1])"#if($foreach.hasNext),#end
+#end
+  }
+}

index.js

@@ -0,0 +1,138 @@
+var clone = require('clone');
+var Velocity = require('velocityjs');
+var _jsonpath = require('JSONPath');
+var jsonpath = function(obj, path) {
+  if (path === '$') {
+    return obj;
+  }
+
+  var result = _jsonpath({
+    json: obj,
+    path: path
+  });
+
+  if (result.length === 1) {
+    return result[0];
+  } else {
+    return result;
+  }
+};
+
+module.exports = function(template, payload, params, context) {
+  params = clone(params || {});
+  params.path = params.path || {};
+  params.querystring = params.querystring || {};
+  params.header = params.header || {};
+
+  context = clone(context || {});
+  context.identity = context.identity || {};
+
+  // API Gateway Mapping Template Reference
+  //   http://docs.aws.amazon.com/apigateway/latest/developerguide/api-gateway-mapping-template-reference.html
+  var data = {
+    context: context,
+    input: {
+      _payload: payload.toString(),
+      path: function(path) {
+        var obj;
+        // if payload starts with `{` or `[` or `"`, treat as JSON
+        if (/^\s*(?:{|\[|")/.test(this._payload)) {
+          obj = JSON.parse(this._payload);
+        } else {
+          // treat as string
+          obj = this._payload;
+        }
+
+        return jsonpath(obj, path);
+      },
+      json: function(path) {
+        var obj = JSON.parse(payload);
+        if (typeof obj === 'string') {
+          // re-parse when parsed payload is string.
+          // because of
+          //   - https://github.com/ToQoz/api-gateway-mapping-template/blob/master/test/_.md#example-0ce08526
+          //   - https://github.com/ToQoz/api-gateway-mapping-template/blob/master/test/_.md#example-1b8d22cd
+          obj = JSON.parse(obj);
+        }
+
+        return JSON.stringify(jsonpath(obj, path));
+      },
+      params: function(x) {
+        switch (true) {
+        case x === undefined:
+          return params;
+        case x in params.path:
+          return params.path[x];
+        case x in params.querystring:
+          return params.querystring[x];
+        case x in params.header:
+          return params.header[x];
+        }
+      },
+    },
+    util: {
+      escapeJavaScript: escapeJavaScript,
+      urlEncode: encodeURIComponent,
+      urlDecode: decodeURIComponent,
+      base64Encode: base64Encode,
+      base64Decode: base64Decode,
+    }
+  };
+
+  // API Gateway convert function to "{}" on toString.
+  var returnEmptyObject = function() { return "{}"; };
+  [
+    data.input,
+    data.input.params,
+    data.input.path,
+    data.input.json,
+    data.util,
+    data.util.escapeJavaScript,
+    data.util.urlEncode,
+    data.util.urlDecode,
+    data.util.base64Encode,
+    data.util.base64Decode,
+  ].forEach(function(f) {
+    f.toString = returnEmptyObject;
+  });
+
+  var ast = Velocity.parse(template.toString());
+  return (new Velocity.Compile(ast)).render(data);
+};
+
+function base64Encode(x) {
+  return (new Buffer(x)).toString('base64');
+}
+
+function base64Decode(x) {
+  return (new Buffer(x, 'base64')).toString();
+}
+
+// I recognize $util.escapeJavaScript as almost `escapeJSONString` and implemented so.
+// c.f. 24.3.2.2 Runtime Semantics: QuoteJSONString ( value )
+//   http://www.ecma-international.org/ecma-262/6.0/index.html#sec-quotejsonstring
+//   DO: 2.a -> 2.b -> 2.c -> 2.d
+var escapeJavaScriptTable = {
+  '"': '\"',    // 2.a
+  '\\': '\\\\',
+  '\b': '\\b',  // 2.b (skip abbrev)
+  '\f': '\\f',
+  '\n': '\\n',
+  '\r': '\\r',
+  '\t': '\\t',
+};
+// 2.c
+for (var code = 0; code < 20; code++) {
+  escapeJavaScriptTable[String.fromCharCode(code)] = ((code < 16) ? '\\u000' : '\\u00') + code.toString(16);
+}
+function escapeJavaScript(x) {
+  return x.split("").map(function(c) {
+    // 2.a - 2.c
+    if (c in escapeJavaScriptTable) {
+      return escapeJavaScriptTable[c];
+    }
+
+    // 2.d
+    return c;
+  }).join("");
+}