Integrating MATLAB with Google BigQuery via REST API - matlab

Question

I'm trying to use MATLAB's webread function to query Google BigQuery via the REST API, and am having issues. The following curl request is successful:
curl 'https://www.googleapis.com/bigquery/v2/projects/<MyProjectId>/queries' \
-X POST \
-H 'Authorization: Bearer <MyBearerToken>' \
-H 'Accept: application/json' \
-H 'Content-Type: application/json' \
--data-binary '{"query":"select count(1) from MyTable","useLegacySql":false}' \
--compressed
However, the following MATLAB code:
api = 'https://www.googleapis.com/bigquery/v2/';
access_token = '<MyAccessToken>';
options = weboptions('RequestMethod', 'post');
r = webread([api 'projects/<MyProjectId>/queries?access_token=' access_token], ...
'query', 'select count(1) from MyTable', ...
'useLegacySql', false, ...
options);
generates the following error:
Error using readContentFromWebService (line 45)
The server returned the status 400 with message "Bad Request" in response to the request to URL
https://www.googleapis.com/bigquery/v2/projects/<MyProjectId>/queries?access_token=<MyAccessToken>&query=select+count(1)+from+<MyTable>&useLegacySql=0
Entering the URL in the MATLAB error into a POST requester shows the following (generic) error, so it appears the URL is malformed:
{
"error": {
"errors": [
{
"domain": "global",
"reason": "required",
"message": "Required parameter is missing"
}
],
"code": 400,
"message": "Required parameter is missing"
}
}
How can I use MATLAB's webread to accomplish the same thing as the above curl request?

Answer 1

It turns out that the webread function doesn't have this functionality. This issue is resolved successfully by using webwrite as follows:
options = weboptions( ...
'RequestMethod', 'post', ...
'MediaType', 'application/json');
data = struct( ...
'query', 'select count(1) from MyTable', ...
'useLegacySql', false);
r = webwrite([api 'projects/<MyProjectId>/queries?access_token=' access_token], ...
data, ...
options);