This collection of Gists contain all kinds of snippets to get information from the VSTS Rest API, that is not easily found in the API

BranchPolicies.http

#Using the great extension in VS Code https://marketplace.visualstudio.com/items?itemName=humao.rest-client
#use the gist GetBasicAuthToken.ps1 to get a valid token from a PAT

@collectionurl=https://account.visualstudio.com
@token=Base64EncryptedPAT e.g. Basic ONOTAVALIDTOKEN=" 

### 
# Get all Available Branch Policies in the project
# --> value.id contains branch policy type id
GET {{collectionurl}}/_apis/projects/?api-version=1.0
Authorization: {{token}}

###
# Get branch policies of all repos and all branches in VSTS project
GET {{collectionurl}}/{{project}}/_apis/policy/configurations?api-version=2.0-preview
Authorization: {{token}}

###
# Create a NEW branch policy 
@repositoryid=<guid of git repo>
@policyid=<guid of policy type>

POST {{collectionurl}}/{{project}}/_apis/policy/configurations?api-version=2.0-preview
Authorization: {{token}}
Content-Type: application/json

{
        "isEnabled": "true",
        "isBlocking": "true",
        "settings": {
            "minimumApproverCount": 1,
            "creatorVoteCounts": "false",
            "allowDownvotes": "false",
            "resetOnSourcePush": "true",
            "scope": [
                {
                    "refName"      : "refs/heads/master",
                    "matchKind"    : "Exact",
                    "repositoryId" : "{{repositoryid}}"
                }
            ],
        },
        "type":{
            "id" : "{{policyid}}"
        }
    } 
    
 ###
 
#Update branch policy. Same as New but PUT and adding polciyconfigurationid that can be retrieved by getting branch policies
# Create Branch Policy on branch
@policyConfigurationId=243

PUT {{collectionurl}}/{{project}}/_apis/policy/configurations/{{policyConfigurationId}}?api-version=2.0-preview
Authorization: {{token}}
Content-Type: application/json

{
        "isEnabled": "true",
        "isBlocking": "true",
        "settings": {
            "minimumApproverCount": 1,
            "creatorVoteCounts": "false",
            "allowDownvotes": "false",
            "resetOnSourcePush": "true",
            "scope": [
                {
                    "refName"      : "refs/heads/master",
                    "matchKind"    : "Exact",
                    "repositoryId" : "{{repositoryid}}"
                }
            ],
        },
        "type":{
            "id" : "{{policyid}}"
        }
    } 

BuildReleaseTasks.http

#Using the great extension in VS Code https://marketplace.visualstudio.com/items?itemName=humao.rest-client
#use the gist GetBasicAuthToken.ps1 to get a valid token from a PAT
@collectionurl=https://account.visualstudio.com
@token=Base64EncryptedPAT e.g. Basic ONOTAVALIDTOKEN=" 

### Get All Build and Release Tasks in account
GET {{collectionurl}}/_apis/distributedtask/tasks
Authorization: {{token}}

GetBasicAuthToken.ps1

function _GetToken {
    param
    (
        [string] $pat
    )

    $userpass = ":$($pat)"
    $encodedCreds = [System.Convert]::ToBase64String([System.Text.Encoding]::ASCII.GetBytes($userpass))
    $accesstoken = "Basic $($encodedCreds)"
    return $accesstoken;
}

ServiceEndPoints.http

#Using the great extension in VS Code https://marketplace.visualstudio.com/items?itemName=humao.rest-client
#use the gist GetBasicAuthToken.ps1 to get a valid token from a PAT
@collectionurl=https://account.visualstudio.com
@token=Base64EncryptedPAT e.g. Basic ONOTAVALIDTOKEN=" 
@projectname=projectname

###
# Get all Service EndPoints
GET {{collectionurl}}/{{projectname}}/_apis/serviceendpoint/endpoints?api-version=4.1-preview.1
Authorization: {{token}}

###
# Get Service EndPoints by type 
GET {{collectionurl}}/{{projectname}}/_apis/serviceendpoint/endpoints?type=azurerm&api-version=4.1-preview.1
Authorization: {{token}}

### 
# Get Service Endpoint details by Id
@serviceendPointId=guid
GET {{collectionurl}}/{{projectname}}/_apis/serviceendpoint/endpoints/{{serviceendPointId}}?api-version=4.1-preview.1
Authorization: {{token}}
# get value.id

### Get Service EndPoint Security Roles
@serviceendPointId=guid of serviceendpoint
@projectid=guid of vsts project --> See VSTSProjects.http
GET {{collectionurl}}/_apis/securityroles/scopes/distributedtask.serviceendpointrole/roleassignments/resources/{{projectid}}_{{serviceendPointId}} 
Authorization: {{token}}

### Set Service EndPoint Security. Add user/Group in Role
@serviceendPointId=guid of serviceendpoint
@projectid=guid of vsts project --> See VSTSProjects.http
@userorgroupid=guid of VSTS user or group

PUT {{collectionurl}}/_apis/securityroles/scopes/distributedtask.serviceendpointrole/roleassignments/resources/{{projectid}}_{{servep}}?api-version=5.0-preview.1
Authorization: {{token}}
Content-Type: application/json

[
    {
        "roleName":"User",
        "userId":"{{userorgroupid}}"
    }
]

###
# Create Service EndPoint
POST {{collectionurl}}/{{projectname}}/_apis/distributedtask/serviceendpoints?api-version=3.0-preview.1
Authorization: {{token}}
Content-Type: application/json

{
  "name": "TestUpdateEP",
  "type": "azurerm",
  "url": "https://management.azure.com/",
   "authorization": {
    "parameters": {
      "serviceprincipalid": "XXX",
      "serviceprincipalkey": "XXX",
      "tenantid": "XXX"
    },
    "scheme": "ServicePrincipal"
  },
  "data": {
    "subscriptionId": "XXX",
    "subscriptionName": "Sub Name"
  }
}

###
# Update Service EndPoint

PUT {{collectionurl}}/{{projectname}}/_apis/distributedtask/serviceendpoints/{{serviceendpointid}}?api-version=3.0-preview.1
Authorization: {{token}}
Content-Type: application/json

{
  "name": "new name",
  "type": "azurerm",
  "url": "https://management.azure.com/",
   "authorization": {
    "parameters": {
      "serviceprincipalid": "XXX",
      "serviceprincipalkey": "XXX",
      "tenantid": "XXX"
    },
    "scheme": "ServicePrincipal"
  },
  "data": {
    "subscriptionId": "XXX",
    "subscriptionName": "Sub Name"
  }
}

VSTSGroupsUsers.http

#Using the great extension in VS Code https://marketplace.visualstudio.com/items?itemName=humao.rest-client
#use the gist GetBasicAuthToken.ps1 to get a valid token from a PAT
@collectionvsspsurl=https://account.vssps.visualstudio.com
@token=Base64EncryptedPAT e.g. Basic ONOTAVALIDTOKEN=" 
@projectid=guid

### Get users / groups in project
#--> get value.id
GET {{collectionvsspsurl}}/_apis/identities?scopeId={{projectid}}&api-version=1.0
Authorization: {{token}}

### Get Groups 
GET {{collectionvsspsurl}}/_apis/graph/groups?api-version=4.1-preview.1
Authorization: {{token}}

### Get members in group, based on descriptor
GET  {{collectionvsspsurl}}/_apis/graph/memberships/vssgp.Uy0xLTktMTU1MTM3NDI0NS0yMjk0OTI4MDIzLTI5MjA5OTMwODktMjg2MzE4MzU3MS0xNTk1Nzg1MzI1LTEtMjYzMjMwMjUwNy0zMTQxNzc2MjAyLTIyNzcwNjk4MTUtMzQ5MzY4NDg2MA?api-version=4.1-preview.1&direction=down
Authorization: {{token}}

VSTSProjects.http

#Using the great extension in VS Code https://marketplace.visualstudio.com/items?itemName=humao.rest-client
#use the gist GetBasicAuthToken.ps1 to get a valid token from a PAT
@collectionurl=https://account.visualstudio.com
@token=Base64EncryptedPAT e.g. Basic ONOTAVALIDTOKEN=" 

### 
# Get all VSTS Projects in account
# --> value.id contains projectid
# --> value.name contains projectname
GET {{collectionurl}}/_apis/projects/?api-version=1.0
Authorization: {{token}}

### 
# Get single VSTS Project by id
@projectid=guid
GET {{collectionurl}}/_apis/projects/{{projectid}}?api-version=1.0
Authorization: {{token}}

### 
# Get single VSTS Project by name
@projectname=projectname
GET {{collectionurl}}/_apis/projects/{{projectname}}?api-version=1.0
Authorization: {{token}}

WebHook.http

#Using the great extension in VS Code https://marketplace.visualstudio.com/items?itemName=humao.rest-client
#use the gist GetBasicAuthToken.ps1 to get a valid token from a PAT

@collectionurl=https://account.visualstudio.com
@token=Base64EncryptedPAT e.g. Basic ONOTAVALIDTOKEN=" 
@projectid=<guid of VSTS project>
@repositoryid=<guid of Git Repo>

POST {{collectionurl}}/_apis/hooks/subscriptions?api-version=4.1"
Authorization: {{token}}
Content-Type: application/json

{
    "publisherId":"tfs",
    "eventType":"git.pullrequest.updated",
    "resourceVersion":"1.0-preview.1",
    "consumerId":"webHooks",
    "consumerActionId":"httpRequest",
    "publisherInputs":{
        "branch":"master",
        "projectId":"{{projectid}}",
        "notificationType":"StatusUpdateNotification",
        "repository":"{{repositoryid}}",
    },
    "consumerInputs":{
        "url":"http://xyz.requestcatcher.com/"
    }
}