Batch Request Mark with airSlate SignNow

Batch request initial

now that we've done some basic standalone requests let's work on making some more complex requests using the batch controller the batch controller much like the name implies allows us to batch together multiple requests and execute multiple sub requests at once using a single message the batch controller even allows us to reduce the response of one sub request in another sub request that's part of the same message at this point you may be wondering why we have this controller well by grouping these requests together we can reduce the number of HTTP requests that need to go over the network and thus reduce the latency which can increase the performance the application querying the pi web api one important thing to note is that all of the sub requests of a batch requests are handled internally by the pi web api service and don't return to the client application until all sub requests have completed the response is then returned in a single large response message we'll talk about some of the batch controller advantages more in depth in the performance section of this course let's start with in a simple example of making a single sub request in a request to the batch controller the pi web api home page this may be a bit of a trivial example but it will get us started looking at the formatting of batch requests if we take a look at the batch request controller and the help files we see that we need to post to the batch controller the batch controller end point will always be the base URL followed by PI Web API slash batch so let's make that HTTP verb request change in fiddler batch requests have a body which is in JSON format this is a Content that we post to the batch controller endpoint next we'll add a body to the request all batch sub requests are specified in the body of the request we'll also need to add the HTTP content type of application slash JSON to let the pi web api know what format to expect the body of the request in so let's start off the request body with an open and closed brackets to wrap our a question this is our top level json element next we'll add an ID that we can use to a differentiate each of the sub requests and the corresponding sub responses let's make this a useful ID for identifying the sub requests like get home page I like to give IDs that have a meaningful name to them so it's easier to identify exactly what each sub request is doing then we'll create a JSON object this JSON object will be the subject west we define the object by putting a colon after the name of the object and then another set of double brackets so we can specify the sub request object the sub request must have at least two parts an HTTP verb such as get post patch put and a resource which will be the URL that we're making the request to we have the option of other properties that we can put in the request such as headers or content properties if we need to have that body it to our sub request in our case we want to use the get method and our URL is going to be the landing page the pi web api if we go ahead and send this we see that we get a response back we have a top level batch response and a sub response contained within those brackets whose ID matches up with our ID for the sub requests one important thing I'd like to note is the use of the 207 HTTP response code multi status in the parent response this means that each of the individual sub responses will have their own HTTP status code for this we see our one sub response has an HTTP status code of 200 so it's important to check each of the individual HTTP status codes when making batch requests it also has some headers which tell us the content is JSON in the content length we see the content has the same response the same links if we run the request for the landing page on its own so now what I'm going to do is add another sub request to this request to the batch controller in this case what I'm going to be doing now is retrieving the home page as well as creating a new element again we want to give this a uniquely identifying name since we're going to be creating an element we'll be using a method of post in order to find the resource we'll need to find the web ID of the database since we need to create an element on a particular database now if we want to make a sub request that as a post for example in this case creating a new element then we need to use the content field content property is always expecting a strain keep in mind that this is the body of the sub request so we'll take an example post and wrap everything in quotes because this is expecting a string and because the content still needs to have quotes in it will need to use back slashes to escape the quotes within our content I'll also need to add the slash elements endpoint if we execute this request we see that we have a 201 response for created on our element and we still have the get home page sub request as well since this method that we use didn't have any content we see that the content is no we covered a lot of material in this video so let's take a quick moment to summarize in this video we introduced the batch controller a powerful tool that allows us to send multiple requests in a single message we demonstrated that the batch controller requests are HTTP POST requests and these requests require a specially formatted request body this request body is in JSON format and must be encased in curly braces each individual request must have a uniquely identifying name it must have an HTTP method whether that be get post delete or something else and it must have a resource or URL to make the sub request against we also showed an example of a request that had more than the bare minimum fields to post a new element we note the use of back slashes to escape the quotes in our content field additionally we showed that each individual sub request and sub response are linked by their uniquely identifying ID we've only just scratched the surface of the batch controller's capabilities so please ensure you're comfortable with this batch controller content before moving on to the next topic