How do you add array in Data portion of Java HTTP POST request?

Question

I'm writing an HTTP POST request in Java using Apache HttpPost and MultipartEntity. In the data portion of the request, I am able to add simple parts using addPart(name, StringBody). However, I need to add body part that is an array of values. How do I do this? The example from a curl request is:

curl -k -H "Content-Type: application/json" --data '{ "name":"someName", 
"email":"[email protected]", "properties" : { "prop1" : "123", "prop2" : "abc" }}' 
-X POST 'https://some.place.com/api/test'

In Java, I can create the request like this, but I need to know how to create the "properties" array value since StringBody is for a single value:

HttpPost httpPost = new HttpPost(newAdultUrl);
MultipartEntity entity = new MultipartEntity();
entity.addPart("name", new StringBody("someName"));
entity.addPart("email", new StringBody("[email protected]"));
entity.addPart("properties", new ??? );
httpPost.setEntity(entity);

Thanks for your help!

Solution 1

Here is one approach that works using StringEntity instead of MultipartEntity:

HttpPost httpPost = new HttpPost(newUrl);
String jsonData = <create using your favorite JSON library>;
StringEntity entity = new StringEntity(jsonData);
httpPost.setEntity(entity);

I would like to see an answer using MultipartEntity if there is one, but this will get the job done.

Solution 2

I did a similar thing as Roberg, but for me worked when I added [] to the end of the keys, like:

 entity.addPart("properties[]", new StringBody("value 1"));
 entity.addPart("properties[]", new StringBody("value 2"));
 entity.addPart("properties[]", new StringBody("value 3"));

Solution 3

In the StringBody pass a method that converts an array to json.
For example JSONArray

new JSONArray(collection).toString()

Comments

[Viruzzo]

You should use a JSON library to do the encoding for you, it's much cleaner and flexible; a simple one is Gson.

[Blake Buckley]

Ok, I have found one approach. I can use a StringEntity instead of a MultipartEntity and create my own JSON string from the various data fields required (we have used both Gson and json-simple in our stack). However, if someone knows of how to use the MultipartEntity approach from my code sample above I would still prefer that approach.

[Blake Buckley]

That would pass the array as a String instead of an array. I need "properties" : {"key":"value"}, not "properties" : "{"key":"value"}".

[Farmor]

try creating an InputStream and use org.apache.http.entity.mime.content.InputStreamBody Actually I misunderstood your question and now I am only guessing