v1.3
Core Concepts
Datasource Reference
Framework Reference
Widget Reference
Query
Query objects are the javascript variables generated for every Query created under a datasource
Run
Each query object contains a run function used to execute the query. The run function is asynchronous by nature and can be chained using the callbacks in the function signature.
Signature
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run(params: Object): Promise
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If you want to use Callbacks (not recommended), copy the signature below:
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run(onSuccess: Function, onError: Function, params: Object): void
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where onSuccess and onError are functions and params is a dictionary of key-value pairs.
We suggest you use the JavaScript Promise signature as it makes the code easy and readable. Callbacks are an old way and will be deprecated soon.
We recommend using the following Promise syntax:
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Query.run(params)
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.then(() => {...}) // run after the query is successful
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.catch(() => {...}) // run if the query encounters any errors
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Arguments
Argument Name
Description
params
An object containing key-value pairs to pass into the query, accessed with
this.params.keyonSuccess
The function to be executed when the run method succeeds
onError
The function to be executed when the run method fails
Passing Params to Run
Most Queries read values directly from entities as global variables. In some cases, like running a query inside a loop, parameters may need to be passed to the query with values contextual to the execution. It can be achieved using the params argument of the run signature. Please see the example below.
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UsersApi.run({ org: "Appsmith" })
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.then((response) => showAlert(response) )
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.catch((error) => showAlert(error, 'error'))
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Params sent to a query can be accessed using the
this keyword1
{{ this.params.key }}
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Please see the quick demo below showing how to access your params from
Query.run(params) within the query. We'll use the Postman Echo API, which will echo our request. We'll pass it { phrase: "hello, world!" } , and then receive it back as a response:Use
{{this.params.key}} within your query to access any params you passed within the .run(params) function.onSuccess
The onSuccess function is run when a query runs successfully. The function returns the response of the query and the params passed to it in the callback arguments.
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onSuccess(response, params): void
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onError
The onError function is run when a query execution fails. The function returns the response of the query and the params passed to it.
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onError(response, params): void
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Data
Each query stores the data from its latest run inside its data property. This property is populated only if the query successfully executes and can be accessed as
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{{ Query1.data }}
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The data type of this property depends on the data.