feat: show schema snippets on hover of decl links in the console

frontend/console/src/features/modules/decls/DataPanel.tsx

@@ -1,6 +1,6 @@
 import type { Data } from '../../../protos/xyz/block/ftl/v1/schema/schema_pb'
+import { DataSnippet } from './DataSnippet'
 import { PanelHeader } from './PanelHeader'
-import { TypeEl } from './TypeEl'
 
 export const DataPanel = ({ value, moduleName, declName }: { value: Data; moduleName: string; declName: string }) => {
   const maybeTypeParams = value.typeParameters.length === 0 ? '' : `<${value.typeParameters.map((p) => p.name).join(', ')}>`
@@ -10,10 +10,7 @@ export const DataPanel = ({ value, moduleName, declName }: { value: Data; module
         data: {moduleName}.{declName}
         {maybeTypeParams}
       </PanelHeader>
-      {value.fields.length === 0 || <div className='mt-8 mb-3'>Fields</div>}
-      <div className='text-xs font-mono inline-grid grid-cols-2 gap-x-4 gap-y-2' style={{ gridTemplateColumns: 'auto auto' }}>
-        {value.fields.map((f, i) => [<span key={`field-name-${i}`}>{f.name}</span>, <TypeEl key={`field-type-${i}`} t={f.type} />])}
-      </div>
+      <DataSnippet value={value} />
     </div>
   )
 }

frontend/console/src/features/modules/decls/DataSnippet.tsx

@@ -0,0 +1,22 @@
+import type { Data } from '../../../protos/xyz/block/ftl/v1/schema/schema_pb'
+import { TypeEl } from './TypeEl'
+
+export const DataSnippet = ({ value }: { value: Data }) => {
+  const maybeTypeParams = value.typeParameters.length === 0 ? '' : `<${value.typeParameters.map((p) => p.name).join(', ')}>`
+  return (
+    <div className='text-xs font-mono'>
+      <div>
+        {value.export ? 'export ' : ''}
+        data {value.name}
+        {maybeTypeParams}
+        {value.fields.length === 0 ? ' {}' : ' {'}
+      </div>
+      {value.fields.length === 0 || (
+        <div className='text-xs font-mono inline-grid grid-cols-2 gap-x-4 gap-y-2 ml-8 my-2' style={{ gridTemplateColumns: 'auto auto' }}>
+          {value.fields.map((f, i) => [<span key={`field-name-${i}`}>{f.name}</span>, <TypeEl key={`field-type-${i}`} t={f.type} />])}
+        </div>
+      )}
+      <div>{value.fields.length === 0 ? '' : '}'}</div>
+    </div>
+  )
+}

frontend/console/src/features/modules/decls/DeclLink.tsx

@@ -1,9 +1,26 @@
-import { useMemo } from 'react'
-import { Link } from 'react-router-dom'
+import { useMemo, useState } from 'react'
+import { useNavigate } from 'react-router-dom'
 import { useSchema } from '../../../api/schema/use-schema'
 import type { PullSchemaResponse } from '../../../protos/xyz/block/ftl/v1/ftl_pb.ts'
+import type { Decl } from '../../../protos/xyz/block/ftl/v1/schema/schema_pb'
+import { DeclSnippet } from './DeclSnippet'
+
+const SnippetContainer = ({ decl }: { decl: Decl }) => {
+  return (
+    <div className='absolute p-4 mt-4 -ml-1 rounded-md dark:bg-gray-700 dark:text-white text-xs'>
+      <div className='absolute -mt-7 dark:text-gray-700'>
+        <svg height='20' width='20'>
+          <title>triangle</title>
+          <polygon points='11,0 9,0 0,20 20,20' fill='currentColor' />
+        </svg>
+      </div>
+      <DeclSnippet decl={decl} />
+    </div>
+  )
+}
 
 export const DeclLink = ({ moduleName, declName }: { moduleName?: string; declName: string }) => {
+  const [isHovering, setIsHovering] = useState(false)
   const schema = useSchema()
   const decl = useMemo(() => {
     const modules = (schema?.data || []) as PullSchemaResponse[]
@@ -20,12 +37,16 @@ export const DeclLink = ({ moduleName, declName }: { moduleName?: string; declNa
     return str
   }
 
+  const navigate = useNavigate()
   return (
-    <Link
-      className='rounded-md cursor-pointer text-indigo-600 dark:text-indigo-400 hover:bg-gray-100 hover:dark:bg-gray-700 p-1 -m-1'
-      to={`/modules/${moduleName}/${decl.value.case}/${declName}`}
+    <span
+      className='inline-block rounded-md cursor-pointer text-indigo-600 dark:text-indigo-400 hover:bg-gray-100 hover:dark:bg-gray-700 p-1 -m-1'
+      onClick={() => navigate(`/modules/${moduleName}/${decl.value.case}/${declName}`)}
+      onMouseEnter={() => setIsHovering(true)}
+      onMouseLeave={() => setIsHovering(false)}
     >
       {str}
-    </Link>
+      {isHovering && <SnippetContainer decl={decl} />}
+    </span>
   )
 }

frontend/console/src/features/modules/decls/DeclSnippet.tsx

@@ -0,0 +1,16 @@
+import type { Decl } from '../../../protos/xyz/block/ftl/v1/schema/schema_pb'
+import { DataSnippet } from './DataSnippet'
+import { EnumSnippet } from './EnumSnippet'
+import { TypeAliasSnippet } from './TypeAliasSnippet'
+
+export const DeclSnippet = ({ decl }: { decl: Decl }) => {
+  switch (decl.value.case) {
+    case 'data':
+      return <DataSnippet value={decl.value.value} />
+    case 'enum':
+      return <EnumSnippet value={decl.value.value} />
+    case 'typeAlias':
+      return <TypeAliasSnippet value={decl.value.value} />
+  }
+  return <div>under construction: {decl.value.case}</div>
+}

frontend/console/src/features/modules/decls/EnumPanel.tsx

@@ -1,75 +1,15 @@
-import type { Enum, Type, Value } from '../../../protos/xyz/block/ftl/v1/schema/schema_pb'
-import { classNames } from '../../../utils'
+import type { Enum } from '../../../protos/xyz/block/ftl/v1/schema/schema_pb'
+import { EnumSnippet } from './EnumSnippet'
 import { PanelHeader } from './PanelHeader'
-import { TypeEl } from './TypeEl'
-
-const VariantComments = ({ comments, fullRow }: { comments?: string[]; fullRow?: boolean }) => {
-  if (!comments) {
-    return
-  }
-  return comments.map((c, i) => (
-    <div key={i} className={classNames('text-gray-500 dark:text-gray-400 mb-0.5', fullRow ? 'col-start-1 col-end-3' : '')}>
-      {c}
-    </div>
-  ))
-}
-
-const VariantValue = ({ name, value }: { name?: string; value?: Value }) => {
-  const v = value?.value.value?.value
-  if (v === undefined) {
-    return
-  }
-  const valueText = value?.value.case === 'intValue' ? v.toString() : `"${v}"`
-  return (
-    <div className='mb-3'>
-      {name && `${name} = `}
-      {valueText}
-    </div>
-  )
-}
-
-const VariantNameAndType = ({ name, t }: { name: string; t: Type }) => {
-  return [
-    <span key='n' className='mb-3'>
-      {name}
-    </span>,
-    <TypeEl key='t' t={t} />,
-  ]
-}
-
-const ValueEnumVariants = ({ value }: { value: Enum }) => {
-  return value.variants.map((v) => [<VariantComments key='c' comments={v.comments} />, <VariantValue key='v' name={v.name} value={v.value} />])
-}
-
-const TypeEnumVariants = ({ value }: { value: Enum }) => {
-  return (
-    <div className='inline-grid grid-cols-2 gap-x-4' style={{ gridTemplateColumns: 'auto auto' }}>
-      {value.variants.map((v) => [
-        <VariantComments key='c' fullRow comments={v.comments} />,
-        <VariantNameAndType key='n' name={v.name} t={v.value?.value.value?.value as Type} />,
-      ])}
-    </div>
-  )
-}
-
-function enumType(value: Enum): string {
-  if (!value.type) {
-    return 'Type'
-  }
-  return value.type.value.case === 'string' ? 'String' : 'Int'
-}
+import { enumType } from './enum.utils'
 
 export const EnumPanel = ({ value, moduleName, declName }: { value: Enum; moduleName: string; declName: string }) => {
-  const isValueEnum = value.type !== undefined
   return (
     <div className='py-2 px-4'>
       <PanelHeader exported={value.export} comments={value.comments}>
         {enumType(value)} Enum: {moduleName}.{declName}
       </PanelHeader>
-      <div className='mt-8'>
-        <div className='mb-2'>Variants</div>
-        <div className='text-xs font-mono'>{isValueEnum ? <ValueEnumVariants value={value} /> : <TypeEnumVariants value={value} />}</div>
-      </div>
+      <EnumSnippet value={value} />
     </div>
   )
 }

frontend/console/src/features/modules/decls/EnumSnippet.tsx

@@ -0,0 +1,77 @@
+import type { Enum, Type, Value } from '../../../protos/xyz/block/ftl/v1/schema/schema_pb'
+import { classNames } from '../../../utils'
+import { TypeEl } from './TypeEl'
+import { enumType } from './enum.utils'
+
+const VariantComments = ({ comments, fullRow }: { comments?: string[]; fullRow?: boolean }) => {
+  if (!comments) {
+    return
+  }
+  return comments.map((c, i) => (
+    <div key={i} className={classNames('text-gray-500 dark:text-gray-400 mb-0.5', fullRow ? 'col-start-1 col-end-3' : '')}>
+      {c}
+    </div>
+  ))
+}
+
+const VariantValue = ({ name, value }: { name?: string; value?: Value }) => {
+  const v = value?.value.value?.value
+  if (v === undefined) {
+    return
+  }
+  const valueText = value?.value.case === 'intValue' ? v.toString() : `"${v}"`
+  return (
+    <div className='mb-2'>
+      {name && `${name} = `}
+      {valueText}
+    </div>
+  )
+}
+
+const VariantNameAndType = ({ name, t }: { name: string; t: Type }) => {
+  return [
+    <span key='n' className='mb-2'>
+      {name}
+    </span>,
+    <TypeEl key='t' t={t} />,
+  ]
+}
+
+const ValueEnumSnippet = ({ value }: { value: Enum }) => {
+  return (
+    <div>
+      <div>
+        {value.export ? 'export ' : ''}
+        enum {value.name}: {`${enumType(value)} {`}
+      </div>
+      <div className='my-2 ml-8'>
+        {value.variants.map((v) => [<VariantComments key='c' comments={v.comments} />, <VariantValue key='v' name={v.name} value={v.value} />])}
+      </div>
+      <div>{'}'}</div>
+    </div>
+  )
+}
+
+const TypeEnumSnippet = ({ value }: { value: Enum }) => {
+  return (
+    <div>
+      <div>
+        {value.export ? 'export ' : ''}
+        enum {value.name}
+        {' {'}
+      </div>
+      <div className='inline-grid grid-cols-2 gap-x-4 mt-2 ml-8' style={{ gridTemplateColumns: 'auto auto' }}>
+        {value.variants.map((v) => [
+          <VariantComments key='c' fullRow comments={v.comments} />,
+          <VariantNameAndType key='n' name={v.name} t={v.value?.value.value?.value as Type} />,
+        ])}
+      </div>
+      <div>{'}'}</div>
+    </div>
+  )
+}
+
+export const EnumSnippet = ({ value }: { value: Enum }) => {
+  const isValueEnum = value.type !== undefined
+  return <div className='text-xs font-mono'>{isValueEnum ? <ValueEnumSnippet value={value} /> : <TypeEnumSnippet value={value} />}</div>
+}

frontend/console/src/features/modules/decls/PanelHeader.tsx

@@ -3,7 +3,7 @@ import { Badge } from '../../../components/Badge'
 
 export const PanelHeader = ({ children, exported, comments }: { children?: ReactNode; exported: boolean; comments?: string[] }) => {
   return (
-    <div className='flex-1'>
+    <div className='flex-1 mb-8'>
       {exported && (
         <div className='mb-2'>
           <Badge name='Exported' />

frontend/console/src/features/modules/decls/TypeAliasPanel.tsx

@@ -1,16 +1,14 @@
 import type { TypeAlias } from '../../../protos/xyz/block/ftl/v1/schema/schema_pb'
 import { PanelHeader } from './PanelHeader'
-import { TypeEl } from './TypeEl'
+import { TypeAliasSnippet } from './TypeAliasSnippet'
 
 export const TypeAliasPanel = ({ value, moduleName, declName }: { value: TypeAlias; moduleName: string; declName: string }) => {
   return (
     <div className='py-2 px-4'>
       <PanelHeader exported={value.export} comments={value.comments}>
         Type Alias: {moduleName}.{declName}
       </PanelHeader>
-      <div className='text-sm my-4'>
-        Underlying type: <TypeEl t={value.type} />
-      </div>
+      <TypeAliasSnippet value={value} />
     </div>
   )
 }

frontend/console/src/features/modules/decls/TypeAliasSnippet.tsx

@@ -0,0 +1,11 @@
+import type { TypeAlias } from '../../../protos/xyz/block/ftl/v1/schema/schema_pb'
+import { TypeEl } from './TypeEl'
+
+export const TypeAliasSnippet = ({ value }: { value: TypeAlias }) => {
+  return (
+    <div className='font-mono text-xs'>
+      {value.export ? 'export ' : ''}
+      typealias {value.name} <TypeEl t={value.type} />
+    </div>
+  )
+}

frontend/console/src/features/modules/decls/TypeEl.tsx

@@ -30,7 +30,7 @@ export const RefLink = ({ r }: { r?: Ref }) => {
   )
 }
 
-export const TypeEl = ({ t }: { t?: Type }) => {
+export const TypeElContents = ({ t }: { t?: Type }) => {
   if (!t) {
     return ''
   }
@@ -68,3 +68,11 @@ export const TypeEl = ({ t }: { t?: Type }) => {
       return t.value.case || ''
   }
 }
+
+export const TypeEl = ({ t }: { t?: Type }) => {
+  return (
+    <span className='font-mono'>
+      <TypeElContents t={t} />
+    </span>
+  )
+}

frontend/console/src/features/modules/decls/enum.utils.ts

@@ -0,0 +1,8 @@
+import type { Enum } from '../../../protos/xyz/block/ftl/v1/schema/schema_pb'
+
+export function enumType(value: Enum): string {
+  if (!value.type) {
+    return 'Type'
+  }
+  return value.type.value.case === 'string' ? 'String' : 'Int'
+}