I want to add an Xively HTTP trigger, but I don't know how to insert the current value into the URL. For example, I have the URL
http://api.thingspeak.com/update?key=jkldfskladfsfdfs&field8=
I want the Xively trigger to insert the current value of my stream after the = sign.
Triggers from Xively make a POST request containing information on the triggering datastream and its conditions to the server you specified when setting up the trigger.
You can't specify the current value as a GET parameter unless you write your own simple service to accept the trigger and then forward the data on to Thingspeak.
Related
In PowerApps, custom connector, I need to define the entire structure of the call when I create the custom connector. I know I can mark certain fields (query params) as parameters that can be filled during run time.
What I try to do is to set the value of one of my security http headers at run time.
My connector, with an API key, makes a call to the /extra/auth end point
/extra/auth returns another key value.
I need to use this new key value in any consecutive calls to my APIs in the HEADER of the request.
I can use two separate connectors for the auth and for the application logic (which seems logic to me).
How would you go to set an http header value at run time for a custom connector - REST api?
I have an application that takes user's input personal details (name, dob, etc.) and looks for a match in the database. I am not creating a record, nor editing one.
Now normally I'd use GET, but GET doesn't allow me a body, and all the data that needs to be checked has to be sent up. I run a database query against all the user's inputs to find a match. If the database returns a match then one is found, otherwise it returns an empty array and no match is found.
So can you recommend the correct RESTful method (HTTP) that I might use for this?
Thanks
As the semantics of the payload of a POST operation are defined by the service itself, it should be used in any case where the other operations do not fit. POST is therefore not only used to create new resources but also to trigger certain calculations and stuff like that.
The general question however is, why do you need such a method? If you fear overwriting any changes done by an other client to the resource between you fetching the state of a resource and requesting an update, i.e., you should consider using conditional requests as defined in RFC 7232 where either an ETag hash is calculated for the current state or the Last-Modified value is taken and added to response header. A client could then send the request including the payload to check first including a If-Match or If-Unmodified-Since header requesting the server to apply an update only if the precondition holds. If it fails the server would tell you that with a 412 Precondition Failed error response.
I am working on a restful api and I need to update a resource (i.e. a customer detail record with 10 fields).
On Add request, I send a Post request with complete record.
On update request, I send a PUT request with complete record of 10 fields.
On Verify request, I send a PUT request with just two fields i.e. recordId and versionNo.
On Delete request, I send a DELETE request with two fields in HttpOptions.
I have few questions that:
Although, it a restful api but specific application which would be used by an angular application, So should I return data in response of POST/PUT requests.
Should I use PATCH in case of Verify (or anyother action where just recordId and versionNo send to server to change some fields) or it is OK to use PUT.
To make uniformity, should I send data in body of delete request as I need recordId and versionNo to delete a record.
Should I use PATCH in case of Verify (or anyother action where just
recordId and versionNo send to server to change some fields) or it is
OK to use PUT.
In RESTful API designs, PUT requests are generally used to add or replace an entire resource, whereas a PATCH should be just used to update an existing resource. A PUT request is called "idempotent" - no matter how many times you send a PUT response, you should get the same result. A PATCH is not idempotent.
example:
PATCH /Cars/vauxhall-astra/engine --> This request would be used to only update the engine of my already existing vauxhall astra
PUT /Cars/renault-clio --> This request would create a new Renault Clio or, if it already exists, replace the entire Clio using the data specified in my request. A Clio would then be guaranteed to exist after my request is successful, regardless of whether it existed or not before.
Although, it a restful api but specific application which would be used by an angular application, So should I return data in response of POST/PUT requests.
Totally up to you, returning data from a POST/PUT is fine - especially if it saves you having to make extra GET api requests. Just always make sure you are only ever returning the data you need from a response.
To make uniformity, should I send data in body of delete request as I need recordId and versionNo to delete a record.
Again it's totally up to you. Whether you use query parameters (e.g. DELETE cars?id=123) or a request body is just your preference, there's nothing in REST that has rules for this.
REST Response
A RESTful API MUST always answer with HTTP codes to client requests:
Success and error responses are a vital part to define how an API is used correctly.
Refer to this guide to solve all your RESTful related questions.
PATCH/PUT
From Wikipedia:
The main difference between the PUT and PATCH method is that the PUT method uses the request URI to supply a modified version of the requested resource which replaces the original version of the resource whereas the PATCH method supplies a set of instructions to modify the resource. If the PATCH document is larger than the size of the new version of the resource sent by the PUT method then the PUT method is preferred.
Also:
Using the PUT method consumes more bandwidth as compared to the PATCH method when only a few changes need to be applied to a resource. But when the PATCH method is used, it usually involves fetching the resource from the server, comparing the original and new files, creating and sending a diff file. On the server side, the server has to read the diff file and make the modifications. This involves a lot of overhead compared to the PUT method.[11] On the other hand, the PUT method requires a GET to be performed before the PUT and it is difficult to ensure that the resource is not modified between the GET and PUT requests.
So I will use PATCH for verifying a resource.
DELETE
Normaly, for DELETE requests, the client specifies the id of the resource and pass it ass a Path Variable on the URL:
curl -X DELETE http://example.com/resource/{id}
But you can pass a body on the request also. This possibility is stated by MDN Mozilla Web DOCS:
Request has body - May
Successful response has body - May
Even though others have answered the question in details before me but still I'm posting this just to provide a handy short difference between all of these HTTP methods
1.HTTP Post:It is used to create an item
2.HTTP Put:It is used to update an item
3.HTTP Patch:It is used to partially update an item
4.HTTP Delete:It is used to delete an item
I've been able to create a Logic App Custom Connector with a webhook trigger by following the docs, however I can't find any documentation on creating a polling trigger. I was only able to find Jeff Hollan's trigger examples, but the polling trigger doesn't seem compatible with the custom connector.
I tried setting up a polling trigger by performing the following steps:
Create an Azure Function with a GET operation expecting a date time query parameter
Have the function return a set of entities that have changed since the last poll
Configure the custom connector to call the Azure Function with the date time query parameter
Configure the response body of the custom connector
Try different things in the 'Trigger configuration' section, but this is most confusing to me.
Whatever I tried, the trigger always fails with a 404 in the trigger outputs, similar to what I initially had with the webhook trigger type.
There are a few things that confuse me:
1. Path of trigger query seems screwed up
It looks like the custom connector UI screws up the path to the trigger. I noticed this when I downloaded the OpenAPI file. The path to my trigger API should be /api/trigger/tasks/completed, but in the OpenAPI file it read /trigger/api/trigger/tasks/completed. It appears the custom connector adds /trigger in front of the path. I sometimes noticed it doing this multiple times, giving me something similar to /trigger/trigger/trigger/api/trigger/tasks/completed. I fixed this in the OpenAPI file and re-imported it into the custom connector.
2. Trigger Configuration section
I don't understand what to do in the Trigger Configuration section of a polling trigger.
I assume the query parameter to monitor state change is some parameter I define myself, e.g. a timestamp, to determine what entities to return.
As the 'select value to pass to selected query param' I would expect I could pick a timestamp from the trigger response. It looks like I can only pick values from a collection, not scalar values from the response as I would expect. How does that work?
Is 'trigger hint' just some information or does it actually control something?
I have implemented an /GET HTTP endpoint to provide search feature. The user sends search terms in query parameters and receives JSON response containing all search results.
Now I have to add a new feature i.e. save search. It means the user sends same search parameters and can also send a boolean parameter say save=true. I have to save the search term in database in this case for future uses. However this parameter is not mandatory.
I am confused over the following points:
Modify same GET HTTP endpoint allowing additional save parameter in query parameters.
Modify same GET HTTP endpoint but passing save parameter in request body instead of query parameters as its backend state changing parameter.
Use separate endpoint for save the parameters using POST method.
What is the standard/acceptable way of doing this?
As far as I understood your question you try to store a search request and by storing it also retrieve the response in one go?
Usually GET is used to retrieve a resources' state though as this method is defined as safe it shouldn't be used if certain state is created for the invoked resource as persisting the search query would be. RFC 7231 further states that:
A payload within a GET request message has no defined semantics; sending a payload body on a GET request might cause some existing implementations to reject the request.
I therefore would refrain from option #1 or #2 as this might break interoperability by certain clients.
POST on the otherhand is defined in RFC 7231 as
The POST method requests that the target resource process the representation enclosed in the request according to the resource's own specific semantics.
It therefore should be used in every situation the other HTTP operations don't fit. The HTTP spec further defines that creating a new resource a 201 Created HTTP status code should be returned including a HTTP response header named Location containing the URI of the created resource. This URI can later be used to retrieve it's state (i.e. the performed search result).
From a client's perspective you are basically storing some query definition on the server and don't care where or how the server is actually persisting it. All you care is to retrieve a handle you can later on invoke. This doesn't prevent the server from returning the current search result within the response payload. And this is what I'd do exactly.
Proposed steps:
Send search request via POST
Store query definition
Generate the URI for the stored query
Perform the search according to the query
Return a response with a 201 Created status code and Location header pointing to the URI of the stored query and add the query result within the response payload
A client can later on use the returned URI to retrieve the current state of the resource, which the server can interpret as: execute the query stored for that URI and return the search result.
How the URI has to look like is not defined by the REST architecture. You might generate UUIDs or generate a hash value based on the query generate. The latter approach has the benefit that multiple identical queries wouldn't result in additional queries created but in the reusage of such. In such cases a redirect to the existing query resource should be performed to tell the client that his query already existed which also teaches the client the actual URI of the query resource as a side effect.