Workflow Engine

This page details the breaking changes in Workflow Engine for the 2023.1 release.

Deep Merge Task Input Variables

Input variables to the deepmerge task that are not objects are ignored to ensure the task does not error and the workflow runs successfully across all versions of IAP.

To illustrate, the input values something and 42 in the figure below will be ignored and treated as empty variables.

Figure: Non-Object Input Variables

The task output returns the following result.

{
  "color": "red",
  "type": "car"
}

What Should I Do?

To fully capture all key values in a newly merged object, review any workflows that might reference the deepmerge task and make sure all input variables are objects.

APIs Removed Due to Scheduled Deprecations

Below is a list of APIs removed from IAP. Our policy is to provide a deprecation notice two (2) release cycles in advance (at a minimum) before the API is removed. This list represents the latest deprecations announced for the 2023.1 release.

What should I do?

Review any custom apps and adapters that might reference any APIs listed below and change them to the replacement call (or remove them if no replacement call is provided).

Item	Route	Description	Deprecation Release	Actual Removal Release	Replacement
addWatchers	POST /workflow_engine/job/watchers/watch	Add watchers to a job.	2021.2	2023.1	POST /operations-manager/jobs/:jobId/watch
cancelJob	POST /workflow_engine/cancelJob	Cancel a job.	2021.2	2023.1	POST /operations-manager/jobs/cancel
claimTask	POST /workflow_engine/tasks/claim	Claim a manual task.	2021.2	2023.1	POST /operations-manager/tasks/:id/claim
continueJob	POST /workflow_engine/jobs/:jobId/continueJob	Continues a job at a task using the finish state of the last iteration.	2021.2	2023.1	POST /operations-manager/tasks/:id/continue
createJobGroupEntry	POST /workflow_engine/jobs/:id/groups	Add a group to a job.	2021.2	2023.1	POST /operations-manager/jobs/:id/groups
deleteJobGroups	DELETE /workflow_engine/jobs/:id/groups	Delete all groups for a job.	2021.2	2023.1	PUT /operations-manager/jobs/:id/groups
find	POST /workflow_engine/jobs/find	Find job documents.	2021.2	2023.1	GET /operations-manager/jobs
findForwardPaths	POST /workflow_engine/findForwardPaths	Find the paths between two tasks in a workflow.	2021.2	2023.1	N/A
finishManualTask	POST /workflow_engine/finishTask	Completes a manual task.	2021.2	2023.1	POST /operations-manager/jobs/:jobId/tasks/:taskId/finish
fixJob	POST /workflow_engine/fixJob	Revert an errored job.	2021.2	2023.1	POST /operations-manager/jobs/:id/revert
getAllLoopTasks	POST /workflow_engine/getAllLoopTasks	Get all loop tasks.	2021.2	2023.1	N/A
getAssociatedJobs	POST /workflow_engine/getAssociatedJobs	Get associated jobs.	2021.2	2023.1	GET /operations-manager/jobs
getEntireJob	GET workflow_engine/getEntireJob/:job_data	Get the entire data of a job.	2021.2	2023.1	GET /operations-manager/jobs
getJob	GET /workflow_engine/getJob/:job_id	Get a job.	2021.2	2023.1	GET /operations-manager/jobs/:id
getJobDetails	GET /workflow_engine/job/:job_id/details	Get details of an active job.	2021.2	2023.1	GET /operations-manager/jobs/:id
getJobFromTaskQuery	POST /workflow_engine/getJobFromTaskQuery	Get job from a task query.	2021.2	2023.1	GET /operations-manager/tasks?dereference=job
getJobList	POST /workflow_engine/getJobList/:status	Get a list of jobs by status.	2021.2	2023.1	GET /operations-manager/jobs
getJobOutput	GET /workflow_engine/job/:job_id/output	Get the output of a completed job.	2021.2	2023.1	GET /operations-manager/job/:id?dereference=output&include=output
getJobShallow	GET /workflow_engine/getJobShallow/:job_data	Get shallow data of a job.	2021.2	2023.1	GET /operations-manager/jobs/:id
getJobVisualizationData	GET /workflow_engine/jobs/visdata/:job_id	Get the visualization data of a job.	2021.2	2023.1	N/A
getManualTaskController	GET /workflow_engine/tasks/controller/job/:jobId/task/:taskId	Get the controller of a manual task.	2021.2	2023.1	GET /operations-manager/jobs/:jobId/tasks/:taskId/manual-controller
getTask	POST /workflow_engine/getTask	Get a tasks.	2021.2	2023.1	GET /operations-manager/tasks
getTaskIterations	GET /workflow_engine/getTaskIterations/:job_id/:task	Get job task iterations.	2020.2	2023.1	POST /workflow_engine/tasks/search
getTaskStatuses	GET /workflow_engine/job/statuses/:job_id	Get the status of each task in a job.	2021.2	2023.1	GET /operations-manager/tasks?equals[job._id]=<job_id>
listJobGroups	GET /workflow_engine/jobs/:id/groups	List the groups that have access to a job.	2021.2	2023.1	GET /operations-manager/jobs?dereference=groups&include=groups instead
pauseJob	POST /workflow_engine/pauseJob	Pause a job.	2021.2	2023.1	POST /operations-manager/jobs/pause
prepareMetricsLogs	GET /workflow_engine/metrics/jobs	Prepare the metrics logs tarball.	2021.2	2023.1	N/A
queryJobs	POST /workflow_engine/queryJobs	Get jobs matching the query.	2021.2	2023.1	GET /operations-manager/jobs
queryTasksBrief	POST /workflow_engine/queryTasksBrief	Get brief information about tasks from the tasks collection.	2021.2	2023.1	GET /operations-manager/tasks
releaseTask	POST /workflow_engine/tasks/release	Release a manual task.	2021.2	2023.1	POST /operations-manager/tasks/:id/release
removeJobGroup	DELETE /workflow_engine/jobs/:id/groups/:group	Remove a group from the list of authorized groups for a job.	2021.2	2023.1	DELETE /operations-manager/jobs/:jobId/groups/:groupId
replaceJobGroups	PUT /workflow_engine/jobs/:id/groups	Overwrite the list of groups that have access to a job.	2021.2	2023.1	PUT /operations-manager/jobs/:id/groups
resumeJob	POST /workflow_engine/resumeJob	Resume a paused or errored job.	2021.2	2023.1	POST /operations-manager/jobs/resume
retryTask	POST /workflow_engine/jobs/:jobId/retryTask	Retries a task with new variables.	2021.2	2023.1	POST /operations-manager/jobs/:jobId/tasks/:taskId/retry
revertToTask	POST /workflow_engine/revertToTask	Revert a job from the current task to the target task.	2021.2	2023.1	POST /operations-manager/jobs/:id/revert
searchJobs	POST /workflow_engine/jobs/search	Search jobs.	2021.2	2023.1	GET /operations-manager/jobs
searchTasks	POST /workflow_engine/tasks/search	Search tasks.	2021.2	2023.1	GET /operations-manager/tasks
startJobWithOptions	POST /workflow_engine/startJobWithOptions/:workflow	Initiate a job in a workflow with options.	2021.2	2023.1	POST /operations-manager/jobs/start
unwatchJob	DELETE /workflow_engine/job/:job_id/watch	Unwatch a job.	2021.2	2023.1	POST /operations-manager/jobs/:jobId/unwatch
validateAllLoops	POST /workflow_engine/validateAllLoops	Validate all loops.	2021.2	2023.1	N/A
watchJob	PUT /workflow_engine/job/:job_id/watch	Watch a job.	2021.2	2023.1	POST /operations-manager/jobs/:jobId/watch

Workflow Engine Methods Replaced in Operations Manager

With the jobs and tasks APIs moving from Workflow Engine (WFE) to Operations Manager (OM), there are some differences in the API response that need to be considered when using any of these APIs. The differences include both the parameters these methods expect and the responses they return.

API Response Differences - Operations Manager vs. Workflow Engine

In general, Operations Manager responses are formatted with a uniform top level structure; all responses will be objects with the following keys: message, data, and metadata.

Key	Description
message	This property will always be populated with a human readable string. This exists for debugging purposes, as well as proxying actionable feedback to a human user.
data	This property will contain any data relevant to the method response, such as a list of jobs, or the result of some action, but is not necessary for every context. In situations where data is not meaningful, it will be set to null.
metadata	This property is used as a container for descriptive data, such as pagination data in a search API, as well as more detailed context for errors such as input validation failures. If a response has no metadata, the key will be set to an empty object ({}).

For more information about the use of a search API in Operations Manager, refer to the Search API documentation in the Operations Manager developer guide.

Differences in Methods - WFE vs. OM Equivalents

This section details the WFE methods that have been proxied or replaced in Operations Manager (OM), along with the success and error responses that are returned.

cancelJob | pauseJob | resumeJob

WFE Method	OM Equivalent Method
POST /cancelJob { job_id }	POST /jobs/cancel { jobIds } (limits jobIds to length <= 100)
POST /pauseJob { job_id }	POST /jobs/pause { jobIds } (limited to 100 jobs)
POST /resumeJob { job_id }	POST /jobs/resume { jobIds } (limited to 100 jobs)

Success Response

WFE: Full updated job document

OM: { message: <success-message>, data: null, metadata: {} }
If you consume the updated job document from WFE cancel/pause/resume, perform a second API call in OM to get the updated jobs: GET /jobs?in[_id]=_id1,_id2,...

Error Response

WFE: String message with response code 500

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad data, 401 for unauthorized, and 500 for internal error.

tasks/claim

WFE Method	OM Equivalent Method
POST /tasks/claim { task_id, user }	POST /tasks/:id/claim and POST /tasks/:id/assign { userId }

Success Response

WFE: Updated task document

OM: { message: <success-message>, data: null, metadata: {} }
If you depend on the updated task document, perform a second API call in OM to get the updated task: GET /tasks/:id

Error Response

WFE: String message with response code 500

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad data, 401 for unauthorized, and 500 for internal error.

tasks/release

WFE Method	OM Equivalent Method
POST /tasks/release { task_id }	POST /tasks/:id/release

Success Response

WFE: Updated task document provided at the root of the response

OM: { message: <success-message>, data: null, metadata: {} }
If you depend on the updated task document, perform a second API call in OM to get the updated task: GET /tasks/:id

Error Response

WFE: String message with response code 500

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad data, 401 for unauthorized, and 500 for internal error

jobs/:id/groups

WFE Method	OM Equivalent Method
GET /jobs/:id/groups	GET /jobs?dereference=groups&include=groups
DELETE /jobs/:id/groups/:group	DELETE /jobs/:jobId/groups/:groupId
PUT /jobs/:id/groups	PUT /jobs/:id/groups
POST /jobs/:id/groups { group }	POST /jobs/:id/groups { groupId }
DELETE /jobs/:id/groups	DELETE /jobs/:id/groups

Success Response

WFE: Boolean indicating success or failure

OM: { message: <success-message>, data: null, metadata: {} }

Error Response

WFE: String message with response code 500

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad data, 401 for unauthorized, and 500 for internal error.

continueJob

WFE Method	OM Equivalent Method
POST /jobs/:jobId/continueJob { jobId, taskId }	POST /jobs/:id/continue { taskId }

Success Response

WFE: Updated job document

OM: { message: <success-message>, data: null, metadata: {} }
If you depend on the updated job document, perform a second API call to get the updated job: GET /jobs/:jobId

Error Response

WFE: String message with response code 500

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad data, 401 for unauthorized, and 500 for internal error.

fixJob

WFE Method	OM Equivalent Method
POST /fixJob { job_id, errored_task, revert_task }	POST /jobs/:id/revert { fromTask, toTask }

Success Response

WFE: Updated job document

OM: { message: <success-message>, data: null, metadata: {} }
If you depend on the updated job document, perform a second API call to get the updated job: GET /jobs/:jobId

Error Response

WFE: String message with response code 500

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad data, 401 for unauthorized, and 500 for internal error.

job_id

WFE Method	OM Equivalent Method
DELETE /job/:job_id/watch	POST /jobs/:id/unwatch
PUT /job/:job_id/watch	POST /jobs/:id/watch

Success Response

WFE: Username of the user added to the watchers list is provided at the root of the response.

OM:

{
  message: <success-message>,
  data: null,
  metadata: {}
}

Error Response

WFE: String message with 500 response code

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad inputs and 500 for internal error.

retryTask

WFE Method	OM Equivalent Method
POST /jobs/:jobId/retryTask { taskId, variables }	POST jobs/:jobId/tasks/:taskId/retry { variables }

Success Response

WFE: Updated job document provided at the root of the response

OM: { message: <success-message>, data: null, metadata: {} }
If you depend on the updated job document, perform a second API call in OM to get the updated job: GET /jobs/:id

Error Response

WFE: String message with response code 500

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad data, 401 for unauthorized, and 500 for internal error.

finishTask

WFE Method	OM Equivalent Method
POST /finishTask { job_id, task_id }	POST jobs/:jobId/tasks/:taskId/finish { finish_state, variables }

Success Response

WFE: Updated job document

OM: { message: <success-message>, data: null, metadata: {} }
If you depend on the updated job document, perform a second API call to get the updated job: GET /jobs/:jobId

Error Response

WFE: String message with response code 500

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad data, 401 for unauthorized, and 500 for internal error.

jobs/find

WFE Method	OM Replacement Method
POST /jobs/find { query, options }	GET /jobs

⚠ Note on querying:

The replacement call uses a query parameter based searching interface rather than one based on JSON in the post body. Refer to the associated docs for more details.

Success Response

WFE: [{ ...job1 }, { ...job2 }, ...]
Array of job documents returned at the root of the response

OM:

{
  message: <success-message>,
  data: [...jobs],
  metadata: {
    "skip": <number>,
    "limit": <number>,
    "nextPageSkip": <null | number>,
    "previousPageSkip": <null | number>,
    "total": <number>,
    "currentPageSize": <number>,
  }
}

Error Response

WFE: String message with response code 500

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad inputs and 500 for internal error.

getAssociatedJobs

WFE Method	OM Replacement Method
POST /getAssociatedJobs { options }	GET /jobs?exclude=transitions,variables&dereference=accounts.metrics.user + Search terms equivalent to options.filter

⚠ Notes:

• Querying: POST /getAssociatedJobs supports filtering via the options.filter. Refer to the OM Search documentation on details related to filtering with GET /jobs.
• Pagination: POST /getAssociatedJobs options.skip and options.limit become ?skip=...&limit=... in GET /jobs.

Success Response

WFE:

{
  results: [...searchResults],
  skip: <number>,
  limit: <number>,
  total: <number>
}

OM:

{
  message: <success-message>,
  data: [...searchResults],
  metadata: {
    skip: <number>,
    limit: <number>,
    nextPageSkip: <null | number>,
    previousPageSkip: <null | number>,
    total: <number>,
    currentPageSize: <number>,
    }
}

Error Response

WFE: String message with response code 500

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad inputs and 500 for internal error.

job_data

WFE Method	OM Replacement Method
GET /getEntireJob/:job_data	GET /jobs/:id?dereference=tasks

Success Response

WFE: Job document is returned at the root of the response

OM:

{
  message: <success-response>,
  data: <job>,
  metadata: {}
}

Error Response

WFE: String message with response code 500

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad inputs and 500 for internal error.

job_id

WFE Method	OM Replacement Method
GET /getJob/:job_id	GET /jobs/:id

Success Response

WFE: Job document is returned at the root of the response

OM:

{
  message: <success-response>,
  data: <job>,
  metadata: {}
}

Error Response

WFE: String message with response code 500

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad inputs and 500 for internal error.

job_id/details

WFE Method	OM Replacement Method
GET /job/:job_id/details	GET /jobs/:id

Success Response

WFE: Job document is returned at the root of the response

OM:

{
  message: <success-response>,
  data: <job>,
  metadata: {}
}

Error Response

WFE: String message with response code 500

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad inputs and 500 for internal error.

getJobFromTaskQuery

WFE Method	OM Replacemment Method
POST /getJobFromTaskQuery { task_query, options }	GET /tasks?dereference=job&<...search-params>

Success Response

WFE:

{
  results: [...jobDocuments],
  skip: <number>,
  limit: <number>,
  total: <number>
}

OM: 

Overall response

{
  message: <success-message>,
  data: [...taskDocumentsWithJobs],
  metadata: {
    skip: <number>,
    limit: <number>,
    nextPageSkip: <null | number>,
    previousPageSkip: <null | number>,
    total: <number>,
    currentPageSize: <number>,
  }
}

Individual task documents
- Note the difference in job document location with the WFE method.

{
  ...ordinaryTaskData,
  job: <complete-parent-job-document>
}

⚠ Note:

Whereas the WFE method returns only jobs themselves as output, the OM replacement method will return tasks at the top level, with jobs nested within the tasks. There is not a direct way to get a list of just the unique jobs returned by this query; this is up to the API caller to implement.

Error Response

WFE: String message with 500 response code

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad inputs and 500 for internal error.

getJobList/status

WFE Method	OM Replacement Method
POST /getJobList/:status { options }	GET /jobs?equals[status]=<status>

Success Response

WFE:

{
  results: [...jobDocuments],
  skip: <number>,
  limit: <number>,
  total: <number>
}

OM:

{
  message: <success-message>,
  data: [...jobDocuments],
  metadata: {
    skip: <number>,
    limit: <number>,
    nextPageSkip: <null | number>,
    previousPageSkip: <null | number>,
    total: <number>,
    currentPageSize: <number>,
  }
}

Error Response

WFE: String message with 500 response code

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad inputs and 500 for internal error.

job_id/output

WFE Method	OM Replacement Method
GET /job/:job_id/output	GET /job/:id?dereference=output&include=output,variables

Success Response

WFE: Raw job output is included at the root of the document. This output is from the workflow's output schema, if it exists; otherwise it is just the current state of the jobs variables.

OM:

{
  message: <success-message>,
  data: {
    output: <null | job-output>,
    variables: <job-variables>
  },
  metadata: {}
}

Error Response

WFE: String message with 500 response code

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad inputs and 500 for internal error.

getJobShallow/job_data

WFE Method	OM Replacement Method
GET /getJobShallow/:job_data	GET /job/:id?exclude=variables&dereference=tasks

Success Response

WFE: Job is included at the root of the response

OM:

{
  message: <success-message>,
  data: <job-document>,
  metadata: {}
}

Error Response

WFE: String message with 500 response code

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad inputs and 500 for internal error.

tasks/controller/job

WFE Method	OM Proxy Method
GET /tasks/controller/job/:jobId/task/:taskId	GET /jobs/:jobId/tasks/:taskId/manual-controller

Success Response

WFE: Manual task controller is returned at the root of the response

OM:

{
  message: <success-message>,
  data: <manual-task-controller>,
  metadata: {}
}

Error Response

WFE: String message with 500 response code

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad inputs, 401 for unauthorized, and 500 for internal error.

getTask { query, filter }

WFE Method	OM Replacement Method
POST /getTask { query, filter }	GET /tasks?limit=1&include=<...fields-from-filter>

⚠ Note:

The Workflow Engine POST /getTask uses the filter parameter to specify which fields to include in the response. To construct an equivalent include expression, please refer to projection section of the OM search API documentation and use the keys of your filter parameter as values in both the include and exclude.

Success Response

WFE: Task document provided in the root of the response

OM:

{
  message: <success-message>,
  data: <task-document>,
  metadata: {}
}

Error Response

WFE: String message with 500 response code

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad inputs, 401 for unauthorized, and 500 for internal error.

getTaskIterations

WFE Method	OM Replacement Method
GET /getTaskIterations/:job_id/:task	GET /job/:id?dereference=tasks&include=tasks.<task-id>.iterations

Success Response

WFE: [{ ...task1 }, { ...task2 }, ...]

OM:

{
  message: <success-message>,
  data: {
    tasks: {
      [<task-id>]: {
        iterations: [
          { ...task1 },
          { ...task2 },
          ...
        ]
      }
    }
  },
  metadata: {}
}

Error Response

WFE: String message with 500 response code

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad inputs, 401 for unauthorized, and 500 for internal error.

job/statuses

WFE Method	OM Replacement Method
GET /job/statuses/:job_id	GET /tasks?equals[job._id]=<job_id>&equals[job.task]=<task>&include=status&dereference=accounts.metrics.owner

Success Response

WFE: Full task documents are provided at the root of the response

OM:

{
  message: <success-message>,
  data: [...taskDocuments],
  metadata: {
    skip: <number>,
    limit: <number>,
    nextPageSkip: <null | number>,
    previousPageSkip: <null | number>,
    total: <number>,
    currentPageSize: <number>,
  }
}

Error Response

WFE: String message with 500 response code

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad inputs and 500 for internal error.

queryJobs

WFE Method	OM Replacement Method
POST /queryJobs	GET /jobs

⚠ Note:

Please use the OM search API documentation as a reference when translating queries provided to POST /queryJobs into query parameters to GET /jobs.

Success Response

WFE: [{ ...job1 }, { ...job2 }, ...]

OM:

{
  message: <success-message>,
  data: [{ ...job1 }, { ...job2 }, ...],
  metadata: {
    skip: <number>,
    limit: <number>,
    nextPageSkip: <null | number>,
    previousPageSkip: <null | number>,
    total: <number>,
    currentPageSize: <number>,
  }
}

Error Response

WFE: String message with 500 response code

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad inputs and 500 for internal error.

queryTasksBrief

WFE Method	OM Replacement Method
POST /queryTasksBrief	GET /tasks?exclude=variables

Success Response

WFE: [{ ...task1 }, { ...task2 }, ...]

OM:

{
  message: <success-message>,
  data: [{ ...task1 }, { ...task2 }, ...],
  metadata: {
    skip: <number>,
    limit: <number>,
    nextPageSkip: <null | number>,
    previousPageSkip: <null | number>,
    total: <number>,
    currentPageSize: <number>,
  }
}

Error Response

WFE: String message with 500 response code

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad inputs and 500 for internal error.

jobs/search

WFE Method	OM Replacement Method
POST /jobs/search	GET /jobs

⚠ Note:

Please use the OM search documentation as a reference when translating search parameters between these two endpoints.

Success Response

WFE: [{ ...job1 }, { ...job2 }, ...]

OM:

{
  message: <success-message>,
  data: [{ ...job1 }, { ...job2 }, ...],
  metadata: {
    skip: <number>,
    limit: <number>,
    nextPageSkip: <null | number>,
    previousPageSkip: <null | number>,
    total: <number>,
    currentPageSize: <number>,
  }
}

Error Response

WFE: String message with 500 response code

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad inputs and 500 for internal error.

tasks/search

WFE Method	OM Replacement Method
POST /tasks/search	GET /tasks

⚠ Note:

Please use the OM search documentation as a reference when translating search parameters between these two endpoints.

Success Response

WFE: [{ ...task1 }, { ...task2 }, ...]

OM:

{
  message: <success-message>,
  data: [{ ...task1 }, { ...task2 }, ...],
  metadata: {
    skip: <number>,
    limit: <number>,
    nextPageSkip: <null | number>,
    previousPageSkip: <null | number>,
    total: <number>,
    currentPageSize: <number>,
  }
}

Error Response

WFE: String message with 500 response code

OM: { message: <error-message>, data: null, metadata: {} } with response code 400 for bad inputs and 500 for internal error.