Example data models and mapping templates for API Gateway
The following sections provide examples of models and mapping templates that could be used as a starting point for your own APIs in API Gateway. For more information about data transformations, see Mapping templates for REST APIs. For more information about data models, see Data models for REST APIs.
Photo album example
The following example shows a photo album API in API Gateway. We provide an example data transformation, additional models, and mapping templates.
Topics
Example data transformation
The following example shows how you can transform input data about photos by using a Velocity Template
Language (VTL) mapping template. For more information about the Velocity Template Language, see Apache Velocity - VTL Reference.
The following example is input data to an integration request.
{ "photos": { "page": 1, "pages": "1234", "perpage": 100, "total": "123398", "photo": [ { "id": "12345678901", "owner": "23456789@A12", "photographer_first_name" : "Saanvi", "photographer_last_name" : "Sarkar", "secret": "abc123d456", "server": "1234", "farm": 1, "title": "Sample photo 1", "ispublic": true, "isfriend": false, "isfamily": false }, { "id": "23456789012", "owner": "34567890@B23", "photographer_first_name" : "Richard", "photographer_last_name" : "Roe", "secret": "bcd234e567", "server": "2345", "farm": 2, "title": "Sample photo 2", "ispublic": true, "isfriend": false, "isfamily": false } ] } }
The following example is a mapping template to transform the photos data.
#set($inputRoot = $input.path('$')) { "photos": [ #foreach($elem in $inputRoot.photos.photo) { "id": "$elem.id", "photographedBy": "$elem.photographer_first_name $elem.photographer_last_name", "title": "$elem.title", "ispublic": $elem.ispublic, "isfriend": $elem.isfriend, "isfamily": $elem.isfamily }#if($foreach.hasNext),#end #end ] }
The following example is output data from the transformation.
{ "photos": [ { "id": "12345678901", "photographedBy": "Saanvi Sarkar", "title": "Sample photo 1", "ispublic": true, "isfriend": false, "isfamily": false }, { "id": "23456789012", "photographedBy": "Richard Roe", "title": "Sample photo 2", "ispublic": true, "isfriend": false, "isfamily": false } ] }
Input model for photo data
You can define a model for your input data. This input model requires that you upload one photo, and it specifies a minimum of 10 photos for each page. You can use this input model to generate an SDK or to turn on a request validation for your API.
{ "$schema": "http://json-schema.org/draft-04/schema#", "title": "PhotosInputModel", "type": "object", "properties": { "photos": { "type": "object", "required" : [ "photo" ], "properties": { "page": { "type": "integer" }, "pages": { "type": "string" }, "perpage": { "type": "integer", "minimum" : 10 }, "total": { "type": "string" }, "photo": { "type": "array", "items": { "type": "object", "properties": { "id": { "type": "string" }, "owner": { "type": "string" }, "photographer_first_name" : {"type" : "string"}, "photographer_last_name" : {"type" : "string"}, "secret": { "type": "string" }, "server": { "type": "string" }, "farm": { "type": "integer" }, "title": { "type": "string" }, "ispublic": { "type": "boolean" }, "isfriend": { "type": "boolean" }, "isfamily": { "type": "boolean" } } } } } } } }
Output model for photo data
You can define a model for your output data. You can use this model for a method response model, which is necessary when you generate a strongly typed SDK for the API. This causes the output to be cast into an appropriate class in Java or Objective-C.
{ "$schema": "http://json-schema.org/draft-04/schema#", "title": "PhotosOutputModel", "type": "object", "properties": { "photos": { "type": "array", "items": { "type": "object", "properties": { "id": { "type": "string" }, "photographedBy": { "type": "string" }, "title": { "type": "string" }, "ispublic": { "type": "boolean" }, "isfriend": { "type": "boolean" }, "isfamily": { "type": "boolean" } } } } } }
Input mapping template for photo data
You can define a mapping template to modify input data. You can modify input data for further function integration or integration responses.
#set($inputRoot = $input.path('$')) { "photos": { "page": $inputRoot.photos.page, "pages": "$inputRoot.photos.pages", "perpage": $inputRoot.photos.perpage, "total": "$inputRoot.photos.total", "photo": [ #foreach($elem in $inputRoot.photos.photo) { "id": "$elem.id", "owner": "$elem.owner", "photographer_first_name" : "$elem.photographer_first_name", "photographer_last_name" : "$elem.photographer_last_name", "secret": "$elem.secret", "server": "$elem.server", "farm": $elem.farm, "title": "$elem.title", "ispublic": $elem.ispublic, "isfriend": $elem.isfriend, "isfamily": $elem.isfamily }#if($foreach.hasNext),#end #end ] } }
News article example
The following example shows a news article API in API Gateway. We provide an example data transformation, additional models, and mapping templates.
Topics
Example data transformation
The following example shows how you can transform input data about a news article by using a Velocity Template
Language (VTL) mapping template. For more information about the Velocity Template Language, see Apache Velocity - VTL Reference.
The following example is input data to an integration request.
{ "count": 1, "items": [ { "last_updated_date": "2015-04-24", "expire_date": "2016-04-25", "author_first_name": "John", "description": "Sample Description", "creation_date": "2015-04-20", "title": "Sample Title", "allow_comment": true, "author": { "last_name": "Doe", "email": "johndoe@example.com", "first_name": "John" }, "body": "Sample Body", "publish_date": "2015-04-25", "version": "1", "author_last_name": "Doe", "parent_id": 2345678901, "article_url": "http://www.example.com/articles/3456789012" } ], "version": 1 }
The following example is a mapping template to transform the news article data.
#set($inputRoot = $input.path('$')) { "count": $inputRoot.count, "items": [ #foreach($elem in $inputRoot.items) { "creation_date": "$elem.creation_date", "title": "$elem.title", "author": "$elem.author.first_name $elem.author.last_name", "body": "$elem.body", "publish_date": "$elem.publish_date", "article_url": "$elem.article_url" }#if($foreach.hasNext),#end #end ], "version": $inputRoot.version }
The following example is output data from the transformation.
{ "count": 1, "items": [ { "creation_date": "2015-04-20", "title": "Sample Title", "author": "John Doe", "body": "Sample Body", "publish_date": "2015-04-25", "article_url": "http://www.example.com/articles/3456789012" } ], "version": 1 }
Input model for news data
You can define a model for your input data. This input model requires that a news article contains a URL, title, and body. You can use this input model to generate an SDK or to turn on a request validation for your API.
{ "$schema": "http://json-schema.org/draft-04/schema#", "title": "NewsArticleInputModel", "type": "object", "properties": { "count": { "type": "integer" }, "items": { "type": "array", "items": { "type": "object", "required": [ "article_url", "title", "body" ], "properties": { "last_updated_date": { "type": "string" }, "expire_date": { "type": "string" }, "author_first_name": { "type": "string" }, "description": { "type": "string" }, "creation_date": { "type": "string" }, "title": { "type": "string" }, "allow_comment": { "type": "boolean" }, "author": { "type": "object", "properties": { "last_name": { "type": "string" }, "email": { "type": "string" }, "first_name": { "type": "string" } } }, "body": { "type": "string" }, "publish_date": { "type": "string" }, "version": { "type": "string" }, "author_last_name": { "type": "string" }, "parent_id": { "type": "integer" }, "article_url": { "type": "string" } } } }, "version": { "type": "integer" } } }
Output model for news data
You can define a model for your output data. You can use this model for a method response model, which is necessary when you generate a strongly typed SDK for the API. This causes the output to be cast into an appropriate class in Java or Objective-C.
{ "$schema": "http://json-schema.org/draft-04/schema#", "title": "PhotosOutputModel", "type": "object", "properties": { "photos": { "type": "array", "items": { "type": "object", "properties": { "id": { "type": "string" }, "photographedBy": { "type": "string" }, "title": { "type": "string" }, "ispublic": { "type": "boolean" }, "isfriend": { "type": "boolean" }, "isfamily": { "type": "boolean" } } } } } }
Input mapping template for news data
You can define a mapping template to modify input data. You can modify input data for further function integration or integration responses.
#set($inputRoot = $input.path('$')) { "count": $inputRoot.count, "items": [ #foreach($elem in $inputRoot.items) { "last_updated_date": "$elem.last_updated_date", "expire_date": "$elem.expire_date", "author_first_name": "$elem.author_first_name", "description": "$elem.description", "creation_date": "$elem.creation_date", "title": "$elem.title", "allow_comment": "$elem.allow_comment", "author": { "last_name": "$elem.author.last_name", "email": "$elem.author.email", "first_name": "$elem.author.first_name" }, "body": "$elem.body", "publish_date": "$elem.publish_date", "version": "$elem.version", "author_last_name": "$elem.author_last_name", "parent_id": $elem.parent_id, "article_url": "$elem.article_url" }#if($foreach.hasNext),#end #end ], "version": $inputRoot.version }
