How to get entire request headers/querystrings in Serverless framework? - amazon-web-services

Question

I started to try Serverless framework, but it looks little confusable for some points...
One of them is request headers/querystrings,
I made request template like this:
s-templates.json
{
"apiRequestTemplate": {
"application/json": {
"httpMethod": "$context.httpMethod",
"body": "$input.json('$')",
"queryParams" : "$input.params().querystring",
"headerParams" : "$input.params().header",
"headerParamNames" : "$input.params().header.keySet()",
"contentTypeValue" : "$input.params().header.get('Content-Type')"
}
}
}
s-function.json
"requestParameters": {},
"requestTemplates": "$${apiRequestTemplate}",
With this setting, I expected to get the request something like this:
{
"body" : {}
"contentTypeValue" : ""
"headerParamNames" : ["Accept", "Accept-Encoding", ... ],
"headerParams" : {
"Accept" : "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8",
"Accept-Encoding" : "gzip, deflate, sdch, br, Accept-Language=ja,en-US;q=0.8,en;q=0.6",
...
},
"httpMethod" : "GET",
"queryParams" : {
"category" : "Some Category"
}
}
But in real, what I get is:
{
"body" : {}
"contentTypeValue" : ""
"headerParamNames" : "[Accept,Accept-Encoding, ... ]",
"headerParams" : "{Accept=text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8", Accept-Encoding=gzip, deflate, sdch, br, Accept-Language=ja,en-US;q=0.8,en;q=0.6", ...}",
"httpMethod" : "GET",
"queryParams" : "{category=Some Category}"
}
This results inconvenient to handle.
I know also, method like below:
s-function.json
"requestParameters": {},
"requestTemplates": {
"application/json": "{\"category\":\"$input.params('category')\"}"
},
But this is also inconvenient need to specify all parameters in configuration..
Is there any way to get entire request-headers / query-strings as json object in lambda function?
Modified after answer
I tried to change s-template.json to
"queryParams" : "$util.parseJson($input.params().querystring)",
"headerParams" : "$util.parseJson($input.params().header)",
But result was same...
And, in AWS document, what I want can be seen here: http://docs.aws.amazon.com/apigateway/latest/developerguide/api-gateway-mapping-template-reference.html#input-variable-reference
#set($allParams = $input.params())
{
"params" : {
#foreach($type in $allParams.keySet())
#set($params = $allParams.get($type))
"$type" : {
#foreach($paramName in $params.keySet())
"$paramName" : "$util.escapeJavaScript($params.get($paramName))"
#if($foreach.hasNext),#end
#end
}
#if($foreach.hasNext),#end
#end
}
}
But I don't know how to set this setting to Serverless framework's s-templates.json...

Answer 1

I use following request template. It will wrap data, path, headers,params,query into a JSON object and pass it to the function.
{
"application/json": {
"data": "$input.json('$')",
"path": "$context.resourcePath",
"method": "$context.httpMethod",
"headers": "{#foreach($header in $input.params().header.keySet())\"$header\": \"$util.escapeJavaScript($input.params().header.get($header))\" #if($foreach.hasNext),#end#end}",
"params": "{#foreach($param in $input.params().path.keySet())\"$param\": \"$util.escapeJavaScript($input.params().path.get($param))\" #if($foreach.hasNext),#end#end}",
"query": "{#foreach($queryParam in $input.params().querystring.keySet())\"$queryParam\": \"$util.escapeJavaScript($input.params().querystring.get($queryParam))\" #if($foreach.hasNext),#end#end}"
}
}
You can refer Apache Velocity Templates to get better understanding about the inner syntax such as #foreach($header in .....).

Answer 2

Have you tried $util.parseJson()? It takes the json as a string and turns it into a traditional json object.