GraphQL API
Overview
As of version 7.0.0, WorkflowGen features the new GraphQL API, which is a modern solution to create process-driven solutions such as mobile apps, web apps, and microservices that require a powerful workflow and BPM engine.
The WorkflowGen GraphQL API is a Node.js application that runs in IIS using iisnode. It enables a high level of customization such as extending the GraphQL schema with custom types, queries or operations, or implementing new authentication methods.
About GraphQL
From the GraphQL website presentation:
"GraphQL is a query language for APIs and a runtime for fulfilling those queries with your existing data. GraphQL provides a complete and understandable description of the data in your API, gives clients the power to ask for exactly what they need and nothing more, makes it easier to evolve APIs over time, and enables powerful developer tools."
GraphQL is a production-ready and an open source technology created by Facebook. In September 2016, GitHub announced its GraphQL API.
"We’ve often heard that our REST API was an inspiration for other companies; countless tutorials refer to our endpoints. Today, we’re excited to announce our biggest change to the API since we snubbed XML in favor of JSON: we’re making the GitHub API available through GraphQL."
GraphQL is a modern API solution for React, React Native, Angular 2, and Vue based applications.
Many GraphQL tutorials are available, it's available in many languages, and it has a large community.
Technical requirements
In addition to the standard WorkflowGen installation, the following components are required:
Note: This library is required if you encounter the error
The specified module could not be found
regarding theedge
andedge-js
libraries when accessing the/wfgen/graphql
,/wfgen/hooks
, or/wfgen/scim
web apps.
For information on the installation procedure, see the WorkflowGen Technical Guide.
Endpoints
The following endpoints are available:
GraphQL API:
http://localhost/wfgen/graphql
GraphiQL IDE:
http://localhost/wfgen/graphql
GraphQL Schema (definition language):
http://localhost/wfgen/graphql/schema
The HTTP GET method is supported on queries only. The HTTP POST method is supported on queries and operations.
HTTP usage
Express-graphql is used to serve the GraphQL HTTP queries:
GraphQL will first look for each parameter in the URL's query-string:
/graphql?query=query+getUser($id:ID){user(id:$id){name}}&variables={"id":"4"}
If not found in the query-string, it will look in the POST request body. If the POST body has not yet been parsed, express-graphql will interpret it depending on the providedContent-Type
header:
application/json
: the POST body will be parsed as a JSON object of parameters.
application/x-www-form-urlencoded
: this POST body will be parsed as a url-encoded string of key-value pairs.
application/graphql
: the POST body will be parsed as GraphQL query string, which provides the query parameter.
Using GraphiQL IDE in a web browser
You can use GraphiQL, "a graphical interactive in-browser GraphQL IDE", to test queries and operations, and to browse the schema documentation.
As of WorkflowGen version 7.15.0, the GraphiQL tool is disabled by default. You can enable it in the GraphQL section on the Integration tab in the Configuration Panel. You can also enable GraphiQL in the WorkflowGen web.config
file by setting the GraphqlGraphiqlEnabled
parameter to Y
.
Configuration
Maximum query content length
The maximum GraphQL query content length can be set by configuring the maxAllowedContentLength
property in the WorkflowGen web.config
file. The following example shows how to configure this property as 1 MB (note that the value should always be specified in bytes, so the value in the example is 1,024,000 bytes). The default value is 30000000 bytes.
Input file allowed folders
You must set the local or remote folder paths where files used by FILE type parameters are located. In the GraphQL section on the Integration tab in the Administration Module Configuration Panel, enter the folder names separated by commas in the Input file allowed folders (comma separated values) field.
Alternately, you can add the folder names separated by commas to the GraphqlInputFileAllowedFolders
parameter in the WorkflowGen web.config
file.
When using file uploads, you don't need to include the original file folder.
Input file allowed HTTP URLs
You can configure allowed HTTP URLs for input files using the Input file allowed HTTP URLs setting in the GraphQL section on the Control Panel Integration tab.
To disallow file uploads using HTTP and/or HTTPS URLs, leave the field empty. To allow certain URLs only, enter comma-separated values according to the table below:
Value | Description |
Empty | No HTTP or HTTPS URLs allowed |
| All HTTP and HTTPS URLs allowed |
| HTTPS URLs only |
| HTTP URLs only |
| HTTP from a specific domain only |
| HTTP from a specific folder only |
| All files and folders whose names start with
|
| Specific file only |
Maximum input file size
In the GraphQL section on the Integration tab in the Administration Module Configuration Panel, enter the maximum input file size in kilobytes in the Maximum input file size (kB) field.
Alternately, you can set the maximum input file content size in kilobytes as the value of the GraphqlMaxInputFileSize
parameter in the WorkflowGen web.config
file.
Maximum input file content size
When working with FILE type parameters content encoded in base64, you must enter the maximum input file content size in kilobytes in the Maximum input file content size (kB) field in the GraphQL section on the Integration tab in the Administration Module Configuration Panel.
Alternately, you can set the maximum input file content size in kilobytes as the value of the GraphqlMaxInputFileContentSize
parameter in the WorkflowGen web.config
file.
FILE type data content is only recommended for small files under 1 MB.
Performance tuning
WorkflowGen is installed with the following default GraphQL settings (located under iisnode
in \wfgen\graphql\web.config
):
The value of the nodeProcessCountPerApplication
setting is set to 0
by default for the best performance in Node.js applications. This creates one node process based on the number of virtual processors that are configured. You can change this value at any time to a custom number of node processes; for example, nodeProcessCountPerApplication=2
will create two node processes independently of the number of virtual processors.
You can also optimize performance if needed by adjusting the maxConcurrentRequestsPerProcess
value based on the number of potential concurrent users and requests.
For more information, see the Best practices and troubleshooting guide for node applications on Azure Web Apps Microsoft article.
Authentication
The following authentication methods are supported:
IIS Basic
WorkflowGen authentication
Custom .NET authentication modules
OpenID Connect
If your WorkflowGen site is configured with Integrated Windows or Basic authentication, you must configure GraphQL with Basic authentication.
HTTPS is required to secure credentials.
The GraphQL Node.js app code inside the \wfgen\graphql
folder can also be customized to accommodate many other authentication methods (such as OAuth2, JWT, etc.) thanks to node libraries such as Passport.js.
System access users
Some operations (such as CancelAction
and UpdateRequestDataset
) require users to have system access to perform the operations. This can be configured in the System operations allowed users field, under Security on the Integration tab in the Configuration Panel.
User impersonation
User impersonation is supported but not recommended, and should be used only when no other technical solutions are possible. (For example, OpenID Connect-based authentication methods allow you to use access tokens to perform API operations on the client and server sides without impersonation.)
System operations allowed users can impersonate another WorkflowGen user account by setting this account's username as the value of the x-wfgen-impersonate-username
HTTP request header.
This request header can be renamed according to your naming convention. You can specify a new header name in the GraphqlImpersonateUserNameHttpHeader
setting in the \wfgen\web.config
file (e.g. <add key="GraphqlImpersonateUserNameHttpHeader" value="my-custom-impersonate-username" />
).
To give or withdraw system operations rights to or from specific users, refer to the System operations allowed users setting in the Security section on the General tab of the Configuration Panel; alternately, you can edit the ProcessesRuntimeWebServiceAllowedUsers
setting in the \wfgen\web.config
file.
Delegation mode
Some GraphQL queries and operations can be executed on behalf of another user. This is possible when a user has created a delegation in WorkflowGen. The delegatee has to specify the user ID of his delegator in the onBehalfOf
argument.
List of actions to do on by the delegatee on behalf of the delegator with the user ID VXNlcjoy
:
When the onBehalfOf
argument is set, it is propagated implicitly to the all the sub-queries and fields until a User type is used.
Global identifiers
Each GraphQL type has an id: ID!
field. This ID is global and is unique for all WorkflowGen objects.
You can use the node(id:ID!)
query to retrieve a WorkflowGen object by its ID.
GraphQL operations
You can copy/paste these queries directly in the GraphiQL IDE. See the Using GraphiQL IDE in a web browser section above for more information.
Using Curl
And the result is:
Viewer basic info (the authenticated user)
My actions to do
Fetch a request by its number
Create a new request
To create a new request from the GraphQL API, make sure that sub-process mode is enabled with public access on the target process. (See the Process form section in the WorkflowGen Administration Guide for more information.)
Request payload:
Response payload:
A parameter's array can be included in the createRequest
operation payload. Be aware that a data with the same name and data type must previously exist in the process for each parameter in the array to store the parameter's value. The following example shows how to send parameters corresponding to the four supported data types (TEXT, NUMERIC, DATETIME, and FILE).
Request payload:
Response payload:
Cancel a request
You can cancel a request by using the request number or the request ID.
Request payload:
Response payload:
Complete an action
To complete an action, provide the request number and the action number, or the action ID.
Request payload:
Response payload:
To complete an action, a parameter array can be included in the request payload arguments.
Request payload:
Response payload:
Cancel an action
To cancel an action, provide the request number and the action number, or the action ID. The following conditions must be met:
The viewer and the user (if they don't share the same identity, as in delegation mode) must have access to the request.
The action must be open.
The action must have a cancel or default exception defined in the transition.
The viewer is:
an administrator or process folder manager OR
a supervisor with cancellation rights OR
the action assignee.
Request payload:
Response payload:
Cancel a request's actions by name
All of the actions with the same name in a request can be cancelled at the same time by using their name in this operation payload. The following conditions are met:
The viewer and the user (if they do not share the same identity, as in delegation mode) must have access to the request.
The action must be open.
The action must have a cancel or default exception defined in the transition.
The viewer is:
an administrator or a process folder manager OR
a supervisor with cancellation rights OR
the action assignee.
Request payload:
Response payload:
Assign an action
To assign an action, provide the request number and the action number, or the action ID; you must also provide the assigneeUserName
or the assigneeId
.
Request payload:
Response payload:
Cancel an action assignment
To cancel an action assignment, you should provide the request number and the action number, or the action ID.
Request payload:
Response payload:
Update request dataset
A request dataset context can be updated by adding a parameter array. In this case a request number or a request ID should be provided.
Request payload:
Response payload:
For more information on FILE parameter manipulations when sent within GraphQL payloads, see the File upload section.
Create a favorite
GraphQL lets users add processes and views to their favorites lists using the process or view IDs.
Request payload:
Response payload:
This code will create a favorite using the process or view description, but adding a custom description is also possible, as shown in the following example:
Request payload:
Response payload:
Update a favorite
GraphQL lets users update an existing favorite process or view by using its favorite ID.
Request payload:
Response payload:
Delete a favorite
GraphQL lets users delete an existing favorite process or view from their favorites list by using its favorites ID.
Request payload:
Response payload:
Add a comment
GraphQL lets users add comments to requests.
Request payload:
Response payload:
Remove a comment
GraphQL lets users remove comments from requests.
Request payload:
Response payload:
Update a comment
Users can update comments if they are administrators, process manager of the process or process supervisor, or standard users who are members of the process participants, have write permissions, and are the comment author.
Request payload:
Response payload:
Create an application
Only administrators can create a workflow application.
Request payload:
Response payload:
Update an application
Only administrators can update a workflow application.
Request payload:
Response payload:
Delete an application
Only administrators can delete a workflow application.
Request payload:
Response payload:
Add an application parameter
Only administrators can add a workflow application parameter.
Request payload:
Response payload:
Remove an application parameter
Only administrators can remove a workflow application parameter if it is not associated to any activity and is not required.
Request payload:
Response payload:
Create a category
Only administrators can create a category.
Request payload:
Response payload:
Update a category
Only administrators can update a category.
Request payload:
Response payload:
Delete a category
Only administrators can delete a category.
Request payload:
Response payload:
Create a process folder
Only administrators can create a process folder.
Request payload:
Response payload:
Update a process folder
Only administrators and the process folder manager can update a process folder.
Request payload:
Response payload:
Delete a process folder
Only administrators can delete a process folder.
Request payload:
Response payload:
Pagination
The GraphQL API supports page number based pagination. You can set a page number
and a size
; otherwise, the default values are:
1
for the page number30
for the page size
The maximum value for the page size is 100
. You can change this setting in the GraphqlMaxPageSize
key in the \wfgen\web.config
file.
The result contains:
totalCount
: The total number of itemshasPreviousPage
hasNextPage
items
: The list of items in the requested page
To retrieve the total count without the list of items, you just need to set the page number to 0
:
File download
As of WorkflowGen version 7.12.0, file data can be downloaded using a blob URL that is returned in the process, request or action datasets, respectively.
Query
Response
File upload
As of version 7.2.0, GraphQL supports the fileValue.updatedAt
, fileValue.content
, and fileValue.url
fields when sending FILE parameters (as shown in the previous example).
The fileValue.updatedAt
field should use the ISO 8601 date format.
File content
The fileValue.content
field should contain the file content encoded in base64. In this case, the fileValue.url
field is not required. You must set the maximum input file content size (see the Configuration section above for instructions on how to set these).
File URL
The fileValue.url
field contains the file URL. When working with FILE parameters, you must set the input file allowed folders and the maximum input file size (see the Configuration section above for instructions on how to set these).
You can also disallow file uploads using HTTP and/or HTTPS URLs setting the Input file allowed HTTP URLs in the GraphQL section on the Integration tab in the Administration Module Configuration Panel (see Input file allowed HTTP URLs in the WorkflowGen Administration Guide).
The following path patterns are supported:
Local file should use the File URI scheme:
Public file URL:
File URL:
Multipart file upload
As of WorkflowGen version 7.14.0, GraphQL supports multipart file uploads for the following mutations:
createRequest
completeAction
completeFormAction
updateRequestDataset
Curl example for a single upload
content-type
should bemultipart/form-data
The
operations
field is required, and contains the GraphQL query:The
Upload
variables should be declared for the mutation:mutation ($fileUpload1: Upload)
input.parameters[X].fileValue
should contain anupload
property whose value is a variable previously declared:parameters:[{name:\\\"FILE1\\\" fileValue:{ upload: $fileUpload1}}]
The
variables
values should be set tonull
:\"variables\": { \"fileUpload1\": null }
The
map
field is required and contains the file mappings:It should follow the
operations
part.The key should be an alphanumeric string that matches the file key (
"1"
in the above example).The value is the variable that will be assigned to the upload:
[\"variables.fileUpload1\"]
For each map entry declared, a file with the same key must be attached.
Each file to be uploaded should contain the alphanumeric key and the file path:
"1=@C:\test1.txt"
Each file attached must match a map entry.
The files must follow the
operation
andmap
parts.
Curl example for multiple uploads
Limitations
The maximum number of uploads in the same request is 30.
The maximum file upload size is set in the
GraphqlMaxInputFileSize
configuration parameter.
The multipart/form-data
content type is only supported for HTTP requests with file uploads. If the fileValue.name
, fileValue.description
, and fileValue.contentType
properties are not defined, they will be set from the uploaded file information; otherwise, they will take the values defined the payload.
viewerAsMember
field usage
viewerAsMember
field usageThe viewerAsMember
field is a Boolean parameter that determines if the viewer has standard user access scope, even if they have an administrator or a process folder manager profile. It can be used by the user(userName:"XXX").requests
, user(userName:"XXX").comments
, and user(userName:"XXX").actions
queries when an administrator or a process folder manager tries to access another user's requests, comments, or actions with a standard user scope.
In the following payload example, an administrator would be able to access Jane Doe's requests, comments, and actions with a standard user access scope:
Logs
All HTTP queries are logged by IIS as other ASP.NET web apps. Node.js application logs are available in the \wfgen\graphql\iisnode\
folder. You can adjust the iisnode log file management in the \wfgen\graphql\web.config
file.
Debug mode
A debug mode can be enabled by setting the GraphqlDebugEnabled
key to Y
in the \wfgen\web.config
file.
In debug mode, some extensions are added to the GraphQL response, and additional error messages are logged in the \wfgen\graphql\iisnode\
folder.
GraphQL desktop client
If you need to work in GraphQL without an internet connection, you can use the Altair GraphQL Client for offline access.
If you're using Basic authentication for GraphQL, download the application from https://altair.sirmuel.design/#download, then set the Authorization header.
If you're using Windows authentication for GraphQL, you can install Altair as a browser extension. No header is required.
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