HTTP Router

In this article

Overview

Use this Snap to route documents to output views based on the incoming HTTP request method. This Snap is primarily meant for use in Pipelines executed through Triggered Tasks. The Snap matches the HTTP request method used in the Triggered Task and routes the document to the corresponding output view as configured for the request method.

Snap Type

HTTP Routers Snap is a Flow-type Snap that executes HTTP requests.

Prerequisites

None.

Support for Ultra Pipelines

Works in Ultra Pipelines.

Limitations and Known Issues

None.

Snap Views

TypeFormatNumber of ViewsExamples of Upstream and Downstream SnapsDescription 
Input 

Document

  • Min: 1
  • Max: 1
  • Mapper Snap
  • Copy Snap
  • JSON Generator
A document containing the data to be processed based on the incoming HTTP request. 
Output

Document

  • Min: 1
  • Max: ∞
  • Mapper Snap
  • Union Snap
  • JSON Formatter

If the input document is routed to more than one output views, they are all instances of the same input document. The Pipeline may fail if any downstream Snap attempts to modify the same document without copying it.

Error

Error handling is a generic way to handle errors without losing data or failing the Snap execution. You can handle the errors that the Snap might encounter while running the Pipeline by choosing one of the following options from the When errors occur list under the Views tab. The available options are:

  • Stop Pipeline Execution: Stops the current pipeline execution when the Snap encounters an error.

  • Discard Error Data and Continue: Ignores the error, discards that record, and continues with the rest of the records.

  • Route Error Data to Error View: Routes the error data to an error view without stopping the Snap execution.

Learn more about Error handling in Pipelines.

Snap Settings

  • Asterisk (*): Indicates a mandatory field.

  • Suggestion icon ( ): Indicates a list that is dynamically populated based on the configuration.

  • Expression icon (): Indicates whether the value is an expression (if enabled) or a static value (if disabled). Learn more about Using Expressions in SnapLogic.

  • Add icon ( ): Indicates that you can add fields in the field set.

  • Remove icon (): Indicates that you can remove fields from the field set.


Field NameTypeDescription
LabelString
Specify a name for the Snap. You can modify this to be more specific, especially if you have more than one of the same Snap in your Pipeline.
Default Value: N/A
ExampleHTTP Router

Routes*



Use this field set to define/map one output view each to one or more of the request methods supportedOnly one method can be specified in each row. Click  to add a new row in this table and define the values accordingly. 

This field set comprises of the following fields:

  • Request method
  • Output view name


Request method

String/Expression/

Suggestion

Select or enter one request method, per each row, depending on the different HTTP requests expected from the Triggered task. The following different request methods are supported:

  • GET
  • POST
  • PUT
  • PATCH
  • DELETE
  • HEAD

This field allows an additional value OTHER to handle request methods coming from the Triggered Task that are not configured in this Snap.

Default Value: N/A
ExampleGET

Output view name

Dropdown list

Select an output view name from this drop-down list for each Request method selected. 

Map the value OTHER to an output view that suits your exception handling requirements. For example, an incoming request method DELETE or HEAD in the above scenario (image) is routed to output4 that corresponds to the value OTHER.

Configure output views beforehand

Ensure that the required number of output views are added for the Snap from the Views tab. These output views will, then, be listed in this field for you to select.

Default Value: N/A
Exampleoutput3

Snap ExecutionDropdown list

Select one of the three following modes in which the Snap executes:

  • Validate & Execute. Performs limited execution of the Snap and generates a data preview during Pipeline validation, then performs full execution of the Snap (unlimited records) during Pipeline runtime.
  • Execute only. Performs full execution of the Snap during Pipeline execution without generating preview data.
  • Disabled. Disables the Snap and all Snaps downstream from it.

Default Value: Validate & Execute
ExampleExecute only

Troubleshooting

ErrorReasonResolution
Failed to evaluate expression: _Reqest_Method.The expression for the Request Method field contains an invalid Pipeline parameter and the Snap is unable to process the incoming requests.

Ensure that you use the correct spelling for Pipeline parameters within the expressions defined in Snap's settings.

Examples

Using HTTP Router Snap to Process the Request from a Triggered Task

The following example Pipeline demonstrates the use of HTTP Router Snap to process an incoming POST request via a Triggered Task. This Pipeline contains the REQUEST_METHOD parameter configured with the value POST.

Triggered TaskPipeline with HTTP Router Snap

Pipeline Properties

When the Triggered Task - Task_On_HTTP_Router is run from the Task's details page, the corresponding Pipeline is executed.

The HTTP Router is configured to route the incoming document to a corresponding output view, matching the Request method value with the REQUEST_METHOD Pipeline parameter.

HTTP Router Snap SettingsHTTP Router Snap Views

In this example, the HTTP Router uses this JSON document and the REQUEST_METHOD from the Triggered Task as inputs. Based on the incoming value for REQUEST_METHOD (POST in this example), the HTTP Router routes the document to the corresponding output view (output1 in the validated Pipeline above). The Pipeline execution continues further to finally write the formatted JSON output into a JSON file.

Download this Pipeline

Using HTTP Router Snap to Process an Ultra Task

The following example Pipeline demonstrates how you can use an HTTP Router Snap to process an incoming PATCH request through an Ultra Task. 

First, we create an Ultra Task for the HTTP Router Pipeline with a request to send a notification to the patchadmin@snaplogic.com whenever a patch is completed.

Ultra Task for HTTP Router SnapPipeline with HTTP Router Snap

We configure the HTTP Router Snap to route incoming data to the corresponding view.

When the Ultra Task - Ultra_Task_On_HTTP_Router is run, the corresponding Pipeline - HTTP Router is executed. Based on the HTTP method, the HTTP router routes the data to the corresponding output view (in this example, the patch request routes to output 4). You can further write the formatted JSON output into a JSON file using the File Writer Snap.

Download this Pipeline.

Downloads

Important steps to successfully reuse Pipelines

  1. Download and import the Pipeline into SnapLogic.
  2. Configure Snap accounts as applicable.
  3. Provide Pipeline parameters as applicable.


  File Modified

File Example_HTTP Router_Ultra_Task.slp

Apr 23, 2021 by Kalpana Malladi

File Example_HTTP_Router_Triggered_Task.slp

Mar 23, 2022 by Kalpana Malladi


Snap Pack History

 Click to view/expand
ReleaseSnap PackDateTypeUpdates
August 2022main17386 StableUpgraded with the latest SnapLogic Platform release.

4.29

main15993

   

Stable

Upgraded with the latest SnapLogic Platform release.

4.28 Patch428patches15026 Latest

Fixed an issue with HTTP Router Snap where the Snap did not work as intended for a GET request that used a Cloud URL when the HTTP Router was the first Snap in the triggered task Pipeline.

4.28main14627 StableEnhanced the Filter Snap with the Null-safe access checkbox. Select this checkbox to consider the valid values in the filter expression and remove the missing or empty data instead of treating them as null.
4.27 Patch427patches13726
 
Latest

Enhanced the Filter Snap with the Null-safe access checkbox. Select this checkbox to consider the missing data or empty value as null when accessing the source path.

4.27main12833
 
StableEnhanced the Gate Snap with the Output Document Content field that enables you to indicate the count of input documents and the specific (first or last) document to include in the output.
4.26main11181
 
Stable

Added Binary Copy Snap to copy a binary stream to the Snap’s output views. You can use this Snap if you want to send the same information to multiple endpoints.

4.25 Patch425patches10571
 
Latest

Enhanced the performance of Binary Router Snap via more efficient IO utilization.

4.25main9554
 
Stable

Enhanced the HTTP Router Snap to support Ultra Pipelines.

4.24main8556
 
Stable

Added the Ignore empty stream checkbox to the Gate Snap Settings

4.23main7430
 
Stable

Enhances the Data Validator Snap by making the Constraint value field as optional under the Constraints.

4.22main6403
 
StableUpgraded with the latest SnapLogic Platform release.
4.21 Patch                     flow8855-Latest

Fixes the Binary Router Snap's failure in Ultra Pipelines by preventing a deep-copy (performing a copy of the original objects recursively) of binary data headers.

4.21snapsmrc542-StableUpgraded with the latest SnapLogic Platform release.
4.20snapsmrc535-Latest
  • Adds a new Snap, Gate, which enables you to consolidate multiple input streams into a single output document where each input stream is displayed as a label containing the list of records that were received by that input view.
  • The Pipeline Execute Snap now provides the following capabilities:
    • Specify the Snaplex on which to run child Pipelines. You can now select the Snaplex on which to run the child Pipelines through the Execute On and Snaplex Path fields. The default option is executing the child Pipeline on the same Snaplex node as the Parent, but you can also specify a different Snaplex through the drop-down list, which includes the option to manually enter a Snaplex name.
    • Configure retry logic for child Pipeline executions. You can now configure retry logic for child Pipeline executions though the following fields: Number of Retries, Retry Interval, and Timeout fields.
4.19snaprsmrc528-StableUpgraded with the latest SnapLogic Platform release.
4.18 Patchflow7743-Latest

Added a property Validate full JSON path to the Data Validator Snap to fix an issue wherein a field validation failure against a constraint does not produce an error.

4.18snapsmrc523-StableUpgraded with the latest SnapLogic Platform release.
4.17 Patchflow7637-Latest

Fixed an issue with the Data Validator Snap wherein the output fails to report all but one of the violations when there are multiple constraints of the Required type.

4.17 PatchALL7402-Latest

Pushed automatic rebuild of the latest version of each Snap Pack to SnapLogic UAT and Elastic servers.

4.17snapsmrc515-Latest

Added the Snap Execution field to all Standard-mode Snaps. In some Snaps, this field replaces the existing Execute during preview check box.

4.16snapsmrc508-Latest

Pipeline Execute Snap: Added the capability to select either document (previously supported) or binary data (new) for your input and output Views.

4.15 Patchflow6263-Latest

Improved the error messages to include the source path of the constraint for data validation failures.

4.15snapsmrc500-StableUpgraded with the latest SnapLogic Platform release.
4.14snapsmrc490-StableUpgraded with the latest SnapLogic Platform release.
4.13snapsmrc486-StableUpgraded with the latest SnapLogic Platform release.
4.12 Patchflow4895-Latest

Fixed an issue in the Data Validator Snap that made multiple copies of lineage on the error path.

4.12snapsmrc480-Stable

Resolved an issue with the Union Snap that caused excessive CPU utilization.

4.11 Patchflow4461-Latest

Fixed an issue with the Pipeline Execute Snap that could cause the parent pipeline to freeze when the child pipeline fails.

4.11 Patchflow4292 -Latest

Resolved an issue with the Union Snap in Ultra Mode that spikes the CPU utilization to ~30% during startup of 120 instances.

4.11snapsmrc465-StableUpgraded with the latest SnapLogic Platform release.
4.10snapsmrc414-StableUpgraded with the latest SnapLogic Platform release.
4.9.0 Patchflow3094-Latest

Addressed an issue in Binary Router where the Snap did not wait until all threads were completed to write data to the output views.

4.9.0 Patchflow3320-Latest

Data Validator Snap - fixed Type constraint feature.

4.9snapsmrc405-StableUpgraded with the latest SnapLogic Platform release.
4.8.0snapsmrc398
Stable

Filter: Snap-aware error handling policy enabled for Spark mode. This ensures the error handling specified on the Snap is used.

4.7.0 Patchflow2598
Latest

Addressed a possible race condition when reusing pipelines with a Pipeline Execute Snap.

4.7.0flow2297
Stable

Fixed an issue with Ultra pipeline when invoking, using Pipeline Execute, a child pipeline that contains a non-Ultra compatible Snap.

4.7.0snapsmrc382
Stable
  • Recommendation: The Pipeline Execute Snap is meant to eventually replace ForEach and Task Execute. It is suggested you use Pipeline Execute for all new pipelines and update existing pipelines at your earliest convenience.
  • Updated the Pipeline Execute Snap with Execute during preview field.
4.6.0 Patchflow1909
Latest

Resolved an issue with Union Snap slowing down pipelines.

4.6.0snapsmrc362
Stable
  • The following Snaps now support error view in Spark mode: Copy, Union.
  • ForEach: The value for the Maximum instances property is limited to a maximum of 100. A value higher than 100 will automatically be limited down to 100 during pipeline execution.
  • Pipeline Execute: Snaplex property added to let you specify the Snaplex on which to run the child pipeline.
  • Resolved an issue in Task Execute Snap that caused an internal server error (status code: 500).
  • Resolved an issue in Pipeline Execute Snap that did not show parameter suggestions when the pipeline is selected from another project.
  • Resolved an issue in Copy Snap that showed errors on the UI while the Javascript was being executed.
  • Resolved an issue in Filter Snap that failed with "could not filter the document" if upstream data for ServiceNow Query.
4.5.1flow1574
Latest
  • Resolved an issue with Pipeline Execute not able to load pipeline selected from the pipeline picker property.
  • Enhanced error handling in Pipeline Execute for when Reuse is enabled and the pipeline path is an expression whose result is not constant.
  • Resolved an issue in Pipeline Execute not including the runtime ID and state in error documents.
4.5.0snapsmrc344
Stable
  • NEW! Pipeline Execute introduced in this release. This Snap provides a way to flexibly and efficiently execute pipelines and flowing documents into and out of these executions.

  • Resolved an issue in Task Execute Snap to ensure JAVA 7 and JAVA 8 Snaplex give the same output.

  • Resolved an issue with the Router Snap routing to the wrong output when used in Spark mode

4.4.0

Stable
  • Resolved an issue with Exit Snap hanging during validation if threshold is not met.

  • Spark support added to the Copy, Filter, Router, and Union Snaps.

4.3.2

Latest
  • Resolved an issue with Task Execute where java.math.BigInteger cannot be cast to java.lang.String exception if input document variable was a numeric type.

  • Resolved an issue with Task Execute failing with expression enabled.

  • Resolved an issue with data preview not working in the ForEach Snap.

  • Resolved an issue with Execute during Preview functionality broken in the ForEach Snap.

  • Resolved an issue with ForEach Snap not representing the output schema correctly during preview.

4.3.1

Latest

Resolved an issue with the ForEach poll interval being inconsistent.

4.3.0

Stable
  • In Data Validator, the pattern option now works with partial matches.

  • Exit Snap 

    • Error handling improved to handle messages that are non-strings.

    • Exit Snap now supports expressions in the Exit error message property.

  • ForEach Snap now generates output documents when run. Output documents will also be produced if a child pipeline called by the ForEach is manually stopped.

4.2.2

Latest
  • Resolved an issue in ForEach where a recursive pipeline in synchronous mode was unable to finish execution.

  • Resolved an issue in Data Validator not working for partial matches.



August 7, 2015 (2015.25/4.2.1)
  • NEW! Exit Snap introduced in this release. This Snap forces a pipeline to stop with a failed status if it receives more records than the user-defined threshold.

  • Resolved error in ForEach Snap where an exposed error view triggered a pipeline failure.



June 27, 2015 (2015.22)

The Router Snap now supports even distribution across all output views if no expressions are defined. With this change, Routes is no longer a required field.



June 6, 2015 (2015.20)
  • Task Execute should have Execute on preview
  • Directory Browser Snap did not render output data when running from "Windows" Groundplex.


May 15, 2015

ForEach: Error was not thrown on validation if the child pipeline was not provided.



May 2, 2015
  • Binary Router: enhanced error handling
  • Filter: bug fixes
  • Router: bug fixes


December 20, 2014

Updated Snaps may include new or changed functionality or be otherwise improved.

  • Data Validator: Type constraint added.
  • Union Snap: Preserve order was removed.


July/Summer 2014
  • NEW! Binary Router Snap introduced in this release.
  • NEW! Task Execute Snap introduced in this release.


June 30, 2014
  • Data Validator (Beta Release). This Snap validates incoming documents and their attributes against constraints you define.
  • ForEach: Addressed an issue with parallel execution not working properly.


April 2014

ForEach Snap updated to support Snaplex selection and pipeline parameters.



January 2014

NEW! ForEach Snap introduced in this release.



November 2013
  • NEW! Head Snap introduced in this release.
  • NEW! Tail Snap introduced in this release.


Initial Release (June 2013)
  • Router Snap introduced in this release.
  • Copy Snap introduced in this release.
  • Union Snap introduced in this release.
  • Filter Snap introduced in this release.