Help Center/ FunctionGraph/ User Guide/ Configuring Function Flows/ Creating a Flow
Updated on 2025-08-19 GMT+08:00
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Creating a Flow

Flows are distributed serverless applications. Visually orchestrate multiple independent serverless functions into an application in sequential, branch, or parallel mode using Low Code technology. In addition, diagnose and debug your applications through a monitoring and management platform.

This section describes how to create and orchestrate a flow. You can create a standard or express flow for your service requirements.

  • Standard flow: better for common services that take a long time to execute. Standard flows can only be invoked asynchronously, and their execution records are persisted for query.
  • Express flow: better for services that take less than 5 minutes to execute and require ultimate performance. Express flows can be invoked synchronously or asynchronously, but their execution records (such as execution node history) are not persisted. The synchronous execution interface returns results, and the execution logs reported to LTS are displayed on the logs page.

    Express flows are available for free trial as a time-limited offer.

Notes and Constraints

Flows are available only in CN East-Shanghai1 and AP-Singapore.

Creating a Flow

Procedure

  1. Log in to the FunctionGraph console. In the navigation pane, choose Flows.
  2. Click Create next to Standard Flow or Express Flow.
  3. Orchestrate the flow by dragging components as in Configuring Function a Flow Component.
    A flow must be a directed acyclic graph (DAG). It has a start node followed only by one node (except the error handling and stop nodes) and ends after another node. You can end a flow in the following ways:
    • Do not connect any conditional, parallel, or start node to the last node of the flow.
    • Add a stop node as the last node of the flow.
  4. After configuring all nodes, click Save in the upper right corner, set parameters, and click OK.
    Table 1 Parameter description

    Parameter

    Description

    Name

    Enter the name of the function flow.

    Enterprise Project

    Select an enterprise project.

    Logs

    Required when creating an express flow.

    • ALL: All events will be recorded.
    • ERROR: Only errors will be recorded.
    • NONE: Log recording is disabled.

    Combine Input

    Whether to combine the previous node's output with the current node's input.

    Streaming Response

    Required when creating an express flow. If this option is enabled, the flow returns data in a stream. For details, see stream file processing.

    The code of function nodes in the flow will call the streaming data API.

    Description

    Description about the flow.

Expression Description

The JSONPath expression used for Retry Condition (JSONPath) in the Error Handling component and for Input Filter Expression and Output Filter Expression in the Conditional Branch component follows the structure: [JSONPath] + [Logical operator] + [Comparison data], for example, $.age >= 20.

Table 2 JSONPath description

Operator

Supported or Not

Description

$

Yes

The root element to query. This starts all regular expressions.

@

Yes

The current node being processed.

.

Yes

Subnode.

[ (, )]

Yes

Array indexes.

[start:end]

Yes

Array slice operator.

[?()]

Yes

Filter expression, which must be evaluated to a Boolean value.
Example 
{  
     "fruits": [ "apple", "orange", "pear" ],  
     "vegetables": [{      
     "veggieName": "potato",
     "veggieLike": true    
      },     
      {       
          "veggieName": "broccoli",      
          "veggieLike": false    
      }] 
}
  • Simple value

    The $.fruits expression obtains all values under fruits.

    The result of $.fruits is ["apple","orange","pear"].

  • Simple filtering

    Expression: $.vegetables[?(@.veggieLike == true)].veggieName

    Meaning: Obtains all values of the key vegetables and outputs the value of veggieName whose veggieLike is True.

    Result: [potato]

Operators

The following data is used as input parameters in the examples:

{
  "name" : "apple",
  "weight": 13.4,
  "type": [3,4,6,8],
  "obj": {
        "a" : 1
   }
}
Table 3 Logical operators

Operator

Description

Example

Return Value

Remarks

==

Equal to

$.name == 'apple'

true

Supported data types: int, float, string, bool, and nil

!=

Not equal to

$.name != 'apple'

false

Supported data types: int, float, string, bool, and nil

<

Less than

$.weight < 12

false

Only numbers supported

>

Greater than

$.weight > 12

true

Only numbers supported

<=

Less than or equal to

$.weight <= 13.4

true

Only numbers supported

>=

Greater than or equal to

$.weight >= 13.4

true

Only numbers supported

'*'

Wildcard

$.weight == '*'

true

Must be used together with ==.

||

Or

$.name == 'apple' || $.weight < 12

true

Used together with () for complex AND/OR logic.

&&

And

$.name == 'apple' && $.weight < 12

false

Used together with () for complex AND/OR logic.
  • A string constant must be enclosed with single quotation marks (''). For example, 'apple'.
  • JSONPath expressions cannot contain =, !=, <, >, |, or &.
Parent Topic: Configuring Function Flows