Is there a problem with the REST interface on CiviCRM API?

Question

I have the CiviCRM API REST interface working fine for retrieving Case information for individual cases. But I'd like to use the options features options.limit and options.offset so I can retrieve data page by page from CiviCRM in response to a search. But whatever I try, nothing seems to alter the limit and the offset numbers of the retrieved records. Only the first 25 records are returned, ie the default number. Has anyone else had a similar problem?

The json payload looks like this:

json={
"return":"id,custom_116,custom_16",
"custom_116":{"IS NOT NULL":1},
"options":{"limit":100,"offset":100}
}

This is the REST format suggested by the API explorer (v3).

Am I doing something wrong? The search criterion ("IS NOT NULL") is ignored as above, but searches works correctly when not in object format, eg "custom_116":"StringToSearch". The limit and offset parameters are also ignored. So it seems likely that the problem is to do with the object format for these parameters. Any ideas? Or is there an alternative way of formatting the query json? Thanks.

CiviCRM 5.9.0 Joomla 3.9.1 php 7.0.31

Answer 1

In the end, I was only able to make it work by using array notation. Some examples below. All these worked in the array notation on the right, but not in the object notation on the left:

"options": {"limit":"100","offset":"100"}  --->  "options[limit]": "1","options[offset]": "100"

"custom_1": {"IS NOT NULL":"1"}  --->  "custom_1[IS NOT NULL]": "1"

"custom_1": {"LIKE": "%stringtosearch%}  --->  "custom_1[LIKE]":"%stringtosearch%"

So in my case my json payload looked like this:

json = {
      "return": "id,custom_116,custom_16",
      "custom_16[IS NOT NULL]": "1",
      "custom_15[<>]": "",
      "options[limit]": "50",
      "options[offset]": "50",
      "options[sort]": "id"
    }

Next task is to work out how to convert the OR option into array notation:

"options":{"or":[["custom_15","custom_16"]]}  ---> ???

Answer 2

I, too, had problems getting the json parameter to work when using the REST URL generated by API Explorer. I kept receiving the following error:

{
"is_error": 1,
"0": "error_message",
"1": "Unable to decode supplied JSON."
}

The response about using array syntax didn't work as written, but it did put me on the right track. Here is what I ended up with:

https://mysite.org/wp-content/plugins/civicrm/civicrm/extern/rest.php?entity=Contact&action=get&api_key=apikey&key=sitekey&sequential=1&json=1&last_name[LIKE]=%Wag%&options[limit]=100

The array syntax isn't inside the json parameter; rather it's part of its own querystring parameter.

Doing this also worked:

https://mysite.org/wp-content/plugins/civicrm/civicrm/extern/rest.php?entity=Contact&action=get&api_key=apikey&key=sitekey&sequential=1&json=1&last_name=Wagner&limit=100

However, array syntax was the only way I could get the comparison to work with something other than equality.