RestClient

RestClient Class

virtual

This class provides an example of an intelligent abstraction for making REST callouts to external endpoints. It utilizes NamedCredentials for security. This class is designated as Virtual so that API Service classes can extend it, and make use of it's methods easily. See the CovidTrackerAPI class for an example of how an API service class can extend RestClient.

This class also provides static methods - so that the abstractions provided can be used in a one-off or ad-hoc manner for situations where a full API Service class isn't needed.

More on Named Credentials: https://sfdc.co/named-credentials

Group Shared Code

See AtFutureRecipes

See QueueableWithCalloutRecipes

See ApiServiceRecipes

See CalloutRecipes

Fields

`defaultHeaders`

TESTVISIBLE

These two properties are not public - which means that in order to manipulate them during a Unit test, we have to mark them

TestVisible

The namedCredentialName also demonstrates how to auto create a getter/setter for a property with the {get;set;} syntax

Signature

private static defaultHeaders

Type

Map<String,String>

Properties

`namedCredentialName`

TESTVISIBLE

The name of the Named Credential to use

Signature

protected namedCredentialName

Type

String

Constructors

`RestClient(namedCredential)`

Constructor that sets Named Credential

Signature

public RestClient(String namedCredential)

Parameters

Name	Type	Description
namedCredential	String	name of the Named Credential to use

`RestClient()`

SUPPRESSWARNINGS

This constructor isn't intended for use, which is why it's access modifier is 'Protected'. However, any child class extending this class will either have to implement constructors matching the one above, or this constructor must exist. In order to make this abstraction as useful as possible, we've elected to leave this constructor here, but unavailable to anything but inner classes and classes that extend this one.

Signature

protected RestClient()

Methods

`makeApiCall(method, path, query, body, headers)`

TESTVISIBLE SUPPRESSWARNINGS

Omnibus callout method. This is the primary method for making a REST callout. Most of the other methods in this class serve as convient, syntactic sugar on this method.

Signature

protected HttpResponse makeApiCall(HttpVerb method, String path, String query, String body, Map<String,String> headers)

Parameters

Name	Type	Description
method	HttpVerb	Enum HTTP verb to use. i.e. GET
path	String	patch component of the callout url i.e. `/services/data/v39.0/SObjects`
query	String	Query portion of the URL i.e. `?q=SELECT Id FROM Account`
body	String	JSON string representing the body of the callout in post/patch situations
headers	Map<String,String>	A map<String,String> of headers to use while making this callout

Return Type

HttpResponse

`makeApiCall(method, path, query, body)`

TESTVISIBLE SUPPRESSWARNINGS

Makes an HTTP Callout to an api resource. Convienence method that assumes the Default Headers.

Signature

protected HttpResponse makeApiCall(HttpVerb method, String path, String query, String body)

Parameters

Name	Type	Description
method	HttpVerb	HTTPVerb to use. See the enum above.
path	String	Http path component of the URL. ie: `/path/to/resource`
query	String	Query component of the URL ie: after `?foo=bar`
body	String	Body to send with this call.

Return Type

HttpResponse

`makeApiCall(method, path, query)`

TESTVISIBLE

convenience version of makeApiCall without body param. Invokes omnibus version above, with blank body param and default headers.

Signature

protected HttpResponse makeApiCall(HttpVerb method, String path, String query)

Parameters

Name	Type	Description
method	HttpVerb	HTTPVerb to use. See the enum above.
path	String	Http path component of the URL. ie: `/path/to/resource`
query	String	Query component of the URL ie: after `?foo=bar`

Return Type

HttpResponse

`makeApiCall(method, path)`

TESTVISIBLE

convenience version of makeApiCall without body or query params. Invokes omnibus version above, with blank body and query params

Signature

protected HttpResponse makeApiCall(HttpVerb method, String path)

Parameters

Name	Type	Description
method	HttpVerb	HTTPVerb to use. See the enum above.
path	String	Http path component of the URL. ie: `/path/to/resource`

Return Type

HttpResponse

`get(path)`

TESTVISIBLE

convenience method for a GET Call that only requires a path

Signature

protected HttpResponse get(String path)

Parameters

Name	Type	Description
path	String	Http path component of the URL. ie: `/path/to/resource`

Return Type

HttpResponse

`get(path, query)`

TESTVISIBLE

convenience method for a GET Call that only requires a path and query

Signature

protected HttpResponse get(String path, String query)

Parameters

Name	Type	Description
path	String	Http path component of the URL. ie: `/path/to/resource`
query	String	Query component of the URL ie: after `?foo=bar`

Return Type

HttpResponse

`del(path)`

TESTVISIBLE

convenience method for deleteing a resource based only on path

Signature

protected HttpResponse del(String path)

Parameters

Name	Type	Description
path	String	Http path component of the URL. ie: `/path/to/resource`

Return Type

HttpResponse

`del(path, query)`

TESTVISIBLE

convenience method for a Delete Call that only requires a path and query

Signature

protected HttpResponse del(String path, String query)

Parameters

Name	Type	Description
path	String	Http path component of the URL. ie: `/path/to/resource`
query	String	Query component of the URL ie: after `?foo=bar`

Return Type

HttpResponse

`post(path, body)`

TESTVISIBLE

convenience method for a POST Call that only requires a path and body

Signature

protected HttpResponse post(String path, String body)

Parameters

Name	Type	Description
path	String	Http path component of the URL. ie: `/path/to/resource`
body	String	JSON string to post

Return Type

HttpResponse

`post(path, query, body)`

TESTVISIBLE

convenience method for a POST Call that only requires a path, query and body

Signature

protected HttpResponse post(String path, String query, String body)

Parameters

Name	Type	Description
path	String	Http path component of the URL. ie: `/path/to/resource`
query	String	Query component of the URL ie: after `?foo=bar`
body	String	JSON string to post

Return Type

HttpResponse

`put(path, body)`

TESTVISIBLE

convenience method for a PUT Call that only requires a path and body

Signature

protected HttpResponse put(String path, String body)

Parameters

Name	Type	Description
path	String	Http path component of the URL. ie: `/path/to/resource`
body	String	JSON string to post

Return Type

HttpResponse

`put(path, query, body)`

TESTVISIBLE

convenience method for a PUT Call that only requires a path, query and body

Signature

protected HttpResponse put(String path, String query, String body)

Parameters

Name	Type	Description
path	String	Http path component of the URL. ie: `/path/to/resource`
query	String	Query component of the URL ie: after `?foo=bar`
body	String	JSON string to post

Return Type

HttpResponse

`patch(path, body)`

TESTVISIBLE

convenience method for a PATCH Call that only requires a path, query and body

Signature

protected HttpResponse patch(String path, String body)

Parameters

Name	Type	Description
path	String	Http path component of the URL. ie: `/path/to/resource`
body	String	JSON string to post

Return Type

HttpResponse

`patch(path, query, body)`

TESTVISIBLE

convenience method for a PATCH Call that only requires a path, query and body

Signature

protected HttpResponse patch(String path, String query, String body)

Parameters

Name	Type	Description
path	String	Http path component of the URL. ie: `/path/to/resource`
query	String	Query component of the URL ie: after `?foo=bar`
body	String	JSON string to post

Return Type

HttpResponse

`ensureStringEndsInSlash(resource)`

TESTVISIBLE

Ensures that the inputted string ends in a / makes callouts more robust.

Signature

protected String ensureStringEndsInSlash(String resource)

Parameters

Name	Type	Description
resource	String	string to ensure ends in `/`

Return Type

String

inputted string with ,[object Object], if it didn't already end in one.

`makeApiCall(namedCredential, method, path, query, body, headers)`

SUPPRESSWARNINGS

A static wrapper for the main makeApiCall method

Signature

public static HttpResponse makeApiCall(String namedCredential, HttpVerb method, String path, String query, String body, Map<String,String> headers)

Parameters

Name	Type	Description
namedCredential	String	The named credential to use
method	HttpVerb	HTTPVerb enum value. See Enum above
path	String	Http path component of the URL. ie: `/path/to/resource`
query	String	Query component of the URL ie: after `?foo=bar`
body	String	JSON string to post
headers	Map<String,String>	Map<String,String> representing outgoing Request
headers

Return Type

HttpResponse

Example

System.Debug(RestClient.makeApiCall('GoogleBooksAPI',
                                     RestClient.HttpVerb.GET,
                                     'volumes',
                                     'q=salesforce',
                                     '',
                                     new Map<String,String>()));

`makeApiCall(namedCredential, method, path, query)`

SUPPRESSWARNINGS

A static wrapper for the main makeApiCall method that assumes default headers.

Signature

public static HttpResponse makeApiCall(String namedCredential, HttpVerb method, String path, String query)

Parameters

Name	Type	Description
namedCredential	String	The named credential to use
method	HttpVerb	HTTPVerb enum value. See Enum above
path	String	Http path component of the URL. ie: `/path/to/resource`
query	String	Query component of the URL ie: after `?foo=bar`

Return Type

HttpResponse

Example

System.Debug(RestClient.makeApiCall('GoogleBooksAPI',
                                     RestClient.HttpVerb.GET,
                                     'volumes',
                                     'q=salesforce'));

`makeApiCall(namedCredential, method, path)`

A static wrapper for the main makeApiCall method where you only need the path

Signature

public static HttpResponse makeApiCall(String namedCredential, HttpVerb method, String path)

Parameters

Name	Type	Description
namedCredential	String	The named credential to use
method	HttpVerb	HTTPVerb enum value. See Enum above
path	String	Http path component of the URL. ie: `/path/to/resource`

Return Type

HttpResponse

Example

System.Debug(RestClient.makeApiCall('GoogleBooksAPI',
                                     RestClient.HttpVerb.GET,
                                     'volumes'));

Enums

HttpVerb Enum

This ENUM lists possible HTTP Verbs. Note: 'Delete' is an Apex Keyword (DML) and as a result, the ENUM value 'DEL' is used for delete.

Values

Value	Description
GET
POST
PATCH
PUT
HEAD
DEL