Extracted subchapters (#391)

* Splitting the page and add to the navigation bar

* Updated the pages

* Extracted one subchapter

docs/StardustDocs/d.tree

@@ -16,7 +16,13 @@
         </toc-element>
         <toc-element topic="hierarchical.md"/>
         <toc-element topic="schemas.md">
-            <toc-element topic="gradle.md"/>
+            <toc-element topic="schemasGradle.md"/>
+            <toc-element topic="schemasJupyter.md"/>
+            <toc-element topic="schemasInheritance.md"/>
+            <toc-element topic="schemasCustom.md"/>
+            <toc-element topic="schemasExternalJupyter.md"/>
+            <toc-element topic="schemasImportOpenApiGradle.md"/>
+            <toc-element topic="schemasImportOpenApiJupyter.md"/>
         </toc-element>
     </toc-element>
     <toc-element topic="installation.md"/>

docs/StardustDocs/topics/collectionsInterop.md

@@ -69,7 +69,7 @@ val df2 = df.add("c") { a + b }
 
 <tip>
 
-To enable extension properties generation you should use [dataframe plugin](gradle.md) 
+To enable extension properties generation you should use [dataframe plugin](schemasGradle.md) 
 for Gradle or [Kotlin jupyter kernel](installation.md)
 
 </tip>

docs/StardustDocs/topics/extensionPropertiesApi.md

@@ -32,7 +32,7 @@ In notebooks, extension properties are generated for [`DataSchema`](schemas.md)
 instance after REPL line execution. 
 After that [`DataFrame`](DataFrame.md)  variable is typed with its own [`DataSchema`](schemas.md), so only valid extension properties corresponding to actual columns in DataFrame will be allowed by the compiler and suggested by completion.
 
-Extension properties can be generated in IntelliJ IDEA using the [Kotlin Dataframe Gradle plugin](gradle.md#configuration).
+Extension properties can be generated in IntelliJ IDEA using the [Kotlin Dataframe Gradle plugin](schemasGradle.md#configuration).
 
 <warning>
 In notebooks generated properties won't appear and be updated until the cell has been executed. It often means that you have to introduce new variable frequently to sync extension properties with actual schema

docs/StardustDocs/topics/installation.md

@@ -156,7 +156,7 @@ tasks.withType(org.jetbrains.kotlin.gradle.tasks.KotlinCompile).configureEach {
 </tabs>
 
 Note that it's better to use the same version for a library and plugin to avoid unpredictable errors.
-After plugin configuration you can try it out with [example](gradle.md#annotation-processing).
+After plugin configuration you can try it out with [example](schemasGradle.md#annotation-processing).
 
 ### Custom configuration
 

docs/StardustDocs/topics/schemas.md

@@ -11,248 +11,33 @@ It ignores order of columns in [`DataFrame`](DataFrame.md), but tracks column hi
 
 In Jupyter environment compile-time [`DataFrame`](DataFrame.md) schema is synchronized with real-time data after every cell execution.
 
-In IDEA projects, you can use the [Gradle plugin](gradle.md#configuration) to extract schema from the dataset
+In IDEA projects, you can use the [Gradle plugin](schemasGradle.md#configuration) to extract schema from the dataset
 and generate extension properties.
 
-## DataSchema workflow in Jupyter
 
-After execution of cell
+## Popular use cases with Data Schemas
 
-<!---FUN createDfNullable-->
+Here's a list of the most popular use cases with Data Schemas.
 
-```kotlin
-val df = dataFrameOf("name", "age")(
-    "Alice", 15,
-    "Bob", null
-)
-```
+* [**Data Schemas in Gradle projects**](schemasGradle.md) <br/>
+  If you are developing a server application and building it with Gradle.
 
-<!---END-->
+* [**DataSchema workflow in Jupyter**](schemasJupyter.md) <br/>
+  If you prefer Notebooks.
 
-the following actions take place:
+* [**Schema inheritance**](schemasInheritance.md) <br/>
+  It's worth knowing how to reuse Data Schemas generated earlier.
 
-1. Columns in `df` are analyzed to extract data schema
-2. Empty interface with [`DataSchema`](schema.md) annotation is generated:
+* [**Custom Data Schemas**](schemasCustom.md) <br/> 
+  Sometimes it is necessary to create your own scheme.
 
-```kotlin
-@DataSchema
-interface DataFrameType
-```
+* [**Use external Data Schemas in Jupyter**](schemasExternalJupyter.md) <br/>
+  Sometimes it is convenient to extract reusable code from Jupyter Notebook into the Kotlin JVM library.
+  Schema interfaces should also be extracted if this code uses Custom Data Schemas.
 
-3. Extension properties for this [`DataSchema`](schema.md) are generated:
+* [**Import OpenAPI Schemas in Gradle project**](schemasImportOpenApiGradle.md) <br/>
+  When you need to take data from the endpoint with OpenAPI Schema.
 
-```kotlin
-val ColumnsContainer<DataFrameType>.age: DataColumn<Int?> @JvmName("DataFrameType_age") get() = this["age"] as DataColumn<Int?>
-val DataRow<DataFrameType>.age: Int? @JvmName("DataFrameType_age") get() = this["age"] as Int?
-val ColumnsContainer<DataFrameType>.name: DataColumn<String> @JvmName("DataFrameType_name") get() = this["name"] as DataColumn<String>
-val DataRow<DataFrameType>.name: String @JvmName("DataFrameType_name") get() = this["name"] as String
-```
-
-Every column produces two extension properties:
-
-* Property for `ColumnsContainer<DataFrameType>` returns column
-* Property for `DataRow<DataFrameType>` returns cell value
-
-4. `df` variable is typed by schema interface:
-
-```kotlin
-val temp = df
-```
-
-```kotlin
-val df = temp.cast<DataFrameType>()
-```
-
-> _Note, that object instance after casting remains the same. See [cast](cast.md).
-
-To log all these additional code executions, use cell magic
-
-```
-%trackExecution -all
-```
-
-## Schema inheritance
-
-In order to reduce amount of generated code, previously generated [`DataSchema`](schema.md) interfaces are reused and only new
-properties are introduced
-
-Let's filter out all `null` values from `age` column and add one more column of type `Boolean`:
-
-```kotlin
-val filtered = df.filter { age != null }.add("isAdult") { age!! > 18 }
-```
-
-New schema interface for `filtered` variable will be derived from previously generated `DataFrameType`:
-
-```kotlin
-@DataSchema
-interface DataFrameType1 : DataFrameType
-```
-
-Extension properties for data access are generated only for new and overriden members of `DataFrameType1` interface:
-
-```kotlin
-val ColumnsContainer<DataFrameType1>.age: DataColumn<Int> get() = this["age"] as DataColumn<Int>
-val DataRow<DataFrameType1>.age: Int get() = this["age"] as Int
-val ColumnsContainer<DataFrameType1>.isAdult: DataColumn<Boolean> get() = this["isAdult"] as DataColumn<Boolean>
-val DataRow<DataFrameType1>.isAdult: String get() = this["isAdult"] as Boolean
-```
-
-Then variable `filtered` is cast to new interface:
-
-```kotlin
-val temp = filtered
-```
-
-```kotlin
-val filtered = temp.cast<DataFrameType1>()
-```
-
-## Custom data schemas
-
-You can define your own [`DataSchema`](schema.md) interfaces and use them in functions and classes to represent [`DataFrame`](DataFrame.md) with
-specific set of columns:
-
-```kotlin
-@DataSchema
-interface Person {
-    val name: String
-    val age: Int
-}
-```
-
-After execution of this cell in Jupyter or annotation processing in IDEA, extension properties for data access will be
-generated. Now we can use these properties to create functions for typed [`DataFrame`](DataFrame.md):
-
-```kotlin
-fun DataFrame<Person>.splitName() = split { name }.by(",").into("firstName", "lastName")
-fun DataFrame<Person>.adults() = filter { age > 18 }
-```
-
-In Jupyter these functions will work automatically for any [`DataFrame`](DataFrame.md) that matches `Person` schema:
-
-<!---FUN extendedDf-->
-
-```kotlin
-val df = dataFrameOf("name", "age", "weight")(
-    "Merton, Alice", 15, 60.0,
-    "Marley, Bob", 20, 73.5
-)
-```
-
-<!---END-->
-
-Schema of `df` is compatible with `Person`, so auto-generated schema interface will inherit from it:
-
-```kotlin
-@DataSchema(isOpen = false)
-interface DataFrameType : Person
-
-val ColumnsContainer<DataFrameType>.weight: DataColumn<Double> get() = this["weight"] as DataColumn<Double>
-val DataRow<DataFrameType>.weight: Double get() = this["weight"] as Double
-```
-
-Despite `df` has additional column `weight`, previously defined functions for `DataFrame<Person>` will work for it:
-
-<!---FUN splitNameWorks-->
-
-```kotlin
-df.splitName()
-```
-
-<!---END-->
-
-```text
-firstName lastName age weight
-   Merton    Alice  15 60.000
-   Marley      Bob  20 73.125
-```
-
-<!---FUN adultsWorks-->
-
-```kotlin
-df.adults()
-```
-
-<!---END-->
-
-```text
-name        age weight
-Marley, Bob  20   73.5
-```
-
-In JVM project you will have to [cast](cast.md) [`DataFrame`](DataFrame.md) explicitly to the target interface:
-
-```kotlin
-df.cast<Person>().splitName()
-```
-
-## Use external data schemas in Jupyter
-
-Sometimes it is convenient to extract reusable code from Jupyter notebook into Kotlin JVM library. If this code
-uses [Custom data schemas](#custom-data-schemas), schema interfaces should also be extracted. In order to enable support
-them in Jupyter, you should register them in
-library [integration class](https://github.com/Kotlin/kotlin-jupyter/blob/master/docs/libraries.md) with `useSchema`
-function:
-
-```kotlin
-@DataSchema
-interface Person {
-    val name: String
-    val age: Int
-}
-
-fun DataFrame<Person>.countAdults() = count { it[Person::age] > 18 }
-
-@JupyterLibrary
-internal class Integration : JupyterIntegration() {
-
-    override fun Builder.onLoaded() {
-        onLoaded {
-            useSchema<Person>()
-        }
-    }
-}
-```
-
-After loading this library into Jupyter notebook, schema interfaces for all [`DataFrame`](DataFrame.md) variables that match `Person`
-schema will derive from `Person`
-
-<!---FUN createDf-->
-
-```kotlin
-val df = dataFrameOf("name", "age")(
-    "Alice", 15,
-    "Bob", 20
-)
-```
-
-<!---END-->
-
-Now `df` is assignable to `DataFrame<Person>` and `countAdults` is available:
-
-```kotlin
-df.countAdults()
-```
-
-## Import Data Schemas, e.g. from OpenAPI, in Jupyter
-
-Similar to [importing OpenAPI data schemas in Gradle projects](gradle.md#openapi-schemas), you can also
-do this in Jupyter notebooks. There is only a slight difference in notation:
-
-Import the schema using any path (`String`), `URL`, or `File`:
-
-```kotlin
-val PetStore = importDataSchema("https://petstore3.swagger.io/api/v3/openapi.json")
-```
-
-and then from next cell you run and onwards, you can call, for example:
-
-```kotlin
-val df = PetStore.Pet.readJson("https://petstore3.swagger.io/api/v3/pet/findByStatus?status=available")
-```
-
-So, very similar indeed!
-
-(Note: The type of `PetStore` will be generated as `PetStoreDataSchema`, but this doesn't affect the way you can use
-it.)
+* [**Import Data Schemas, e.g. from OpenAPI, in Jupyter**](schemasImportOpenApiJupyter.md) <br/>
+  Similar to [importing OpenAPI Data Schemas in Gradle projects](schemasImportOpenApiGradle.md), 
+  you can also do this in Jupyter Notebooks.

docs/StardustDocs/topics/schemasCustom.md

@@ -0,0 +1,80 @@
+[//]: # (title: Custom Data Schemas)
+
+<!---IMPORT org.jetbrains.kotlinx.dataframe.samples.api.Schemas-->
+
+You can define your own [`DataSchema`](schema.md) interfaces and use them in functions and classes to represent [`DataFrame`](DataFrame.md) with
+specific set of columns:
+
+```kotlin
+@DataSchema
+interface Person {
+    val name: String
+    val age: Int
+}
+```
+
+After execution of this cell in Jupyter or annotation processing in IDEA, extension properties for data access will be
+generated. Now we can use these properties to create functions for typed [`DataFrame`](DataFrame.md):
+
+```kotlin
+fun DataFrame<Person>.splitName() = split { name }.by(",").into("firstName", "lastName")
+fun DataFrame<Person>.adults() = filter { age > 18 }
+```
+
+In Jupyter these functions will work automatically for any [`DataFrame`](DataFrame.md) that matches `Person` schema:
+
+<!---FUN extendedDf-->
+
+```kotlin
+val df = dataFrameOf("name", "age", "weight")(
+    "Merton, Alice", 15, 60.0,
+    "Marley, Bob", 20, 73.5
+)
+```
+
+<!---END-->
+
+Schema of `df` is compatible with `Person`, so auto-generated schema interface will inherit from it:
+
+```kotlin
+@DataSchema(isOpen = false)
+interface DataFrameType : Person
+
+val ColumnsContainer<DataFrameType>.weight: DataColumn<Double> get() = this["weight"] as DataColumn<Double>
+val DataRow<DataFrameType>.weight: Double get() = this["weight"] as Double
+```
+
+Despite `df` has additional column `weight`, previously defined functions for `DataFrame<Person>` will work for it:
+
+<!---FUN splitNameWorks-->
+
+```kotlin
+df.splitName()
+```
+
+<!---END-->
+
+```text
+firstName lastName age weight
+   Merton    Alice  15 60.000
+   Marley      Bob  20 73.125
+```
+
+<!---FUN adultsWorks-->
+
+```kotlin
+df.adults()
+```
+
+<!---END-->
+
+```text
+name        age weight
+Marley, Bob  20   73.5
+```
+
+In JVM project you will have to [cast](cast.md) [`DataFrame`](DataFrame.md) explicitly to the target interface:
+
+```kotlin
+df.cast<Person>().splitName()
+```