Add Architecture Diagrams

README.md

@@ -675,6 +675,140 @@ pie showData
     "C" : 30
 ```
 
+### Architecture Diagrams (beta feature)
+
+[The mermaid provides a feature to visualize infrastructure architecture as a beta version](https://mermaid.js.org/syntax/architecture.html), and that feature has been introduced.
+
+```go
+package main
+
+import (
+	"io"
+	"os"
+
+	"github.com/nao1215/markdown"
+	"github.com/nao1215/markdown/mermaid/arch"
+)
+
+//go:generate go run main.go
+
+func main() {
+	f, err := os.Create("generated.md")
+	if err != nil {
+		panic(err)
+	}
+	defer f.Close()
+
+	diagram := arch.NewArchitecture(io.Discard).
+		Service("left_disk", arch.IconDisk, "Disk").
+		Service("top_disk", arch.IconDisk, "Disk").
+		Service("bottom_disk", arch.IconDisk, "Disk").
+		Service("top_gateway", arch.IconInternet, "Gateway").
+		Service("bottom_gateway", arch.IconInternet, "Gateway").
+		Junction("junctionCenter").
+		Junction("junctionRight").
+		LF().
+		Edges(
+			arch.Edge{
+				ServiceID: "left_disk",
+				Position:  arch.PositionRight,
+				Arrow:     arch.ArrowNone,
+			},
+			arch.Edge{
+				ServiceID: "junctionCenter",
+				Position:  arch.PositionLeft,
+				Arrow:     arch.ArrowNone,
+			}).
+		Edges(
+			arch.Edge{
+				ServiceID: "top_disk",
+				Position:  arch.PositionBottom,
+				Arrow:     arch.ArrowNone,
+			},
+			arch.Edge{
+				ServiceID: "junctionCenter",
+				Position:  arch.PositionTop,
+				Arrow:     arch.ArrowNone,
+			}).
+		Edges(
+			arch.Edge{
+				ServiceID: "bottom_disk",
+				Position:  arch.PositionTop,
+				Arrow:     arch.ArrowNone,
+			},
+			arch.Edge{
+				ServiceID: "junctionCenter",
+				Position:  arch.PositionBottom,
+				Arrow:     arch.ArrowNone,
+			}).
+		Edges(
+			arch.Edge{
+				ServiceID: "junctionCenter",
+				Position:  arch.PositionRight,
+				Arrow:     arch.ArrowNone,
+			},
+			arch.Edge{
+				ServiceID: "junctionRight",
+				Position:  arch.PositionLeft,
+				Arrow:     arch.ArrowNone,
+			}).
+		Edges(
+			arch.Edge{
+				ServiceID: "top_gateway",
+				Position:  arch.PositionBottom,
+				Arrow:     arch.ArrowNone,
+			},
+			arch.Edge{
+				ServiceID: "junctionRight",
+				Position:  arch.PositionTop,
+				Arrow:     arch.ArrowNone,
+			}).
+		Edges(
+			arch.Edge{
+				ServiceID: "bottom_gateway",
+				Position:  arch.PositionTop,
+				Arrow:     arch.ArrowNone,
+			},
+			arch.Edge{
+				ServiceID: "junctionRight",
+				Position:  arch.PositionBottom,
+				Arrow:     arch.ArrowNone,
+			}).String() //nolint
+
+	err = markdown.NewMarkdown(f).
+		H2("Architecture Diagram").
+		CodeBlocks(markdown.SyntaxHighlightMermaid, diagram).
+		Build()
+
+	if err != nil {
+		panic(err)
+	}
+```
+
+Plain text output: [markdown is here](./doc/architecture/generated.md)
+````
+## Architecture Diagram
+```mermaid
+architecture-beta
+    service left_disk(disk)[Disk]
+    service top_disk(disk)[Disk]
+    service bottom_disk(disk)[Disk]
+    service top_gateway(internet)[Gateway]
+    service bottom_gateway(internet)[Gateway]
+    junction junctionCenter
+    junction junctionRight
+
+    left_disk:R -- L:junctionCenter
+    top_disk:B -- T:junctionCenter
+    bottom_disk:T -- B:junctionCenter
+    junctionCenter:R -- L:junctionRight
+    top_gateway:B -- T:junctionRight
+    bottom_gateway:T -- B:junctionRight
+```
+````
+
+![Architecture Diagram](./doc/architecture/image.png)
+
 ## Creating an index for a directory full of markdown files
 The markdown package can create an index for Markdown files within the specified directory. This feature was added to generate indexes for Markdown documents produced by [nao1215/spectest](https://github.com/nao1215/spectest).
 

doc/architecture/generated.md

@@ -0,0 +1,18 @@
+## Architecture Diagram
+```mermaid
+architecture-beta
+    service left_disk(disk)[Disk]
+    service top_disk(disk)[Disk]
+    service bottom_disk(disk)[Disk]
+    service top_gateway(internet)[Gateway]
+    service bottom_gateway(internet)[Gateway]
+    junction junctionCenter
+    junction junctionRight
+
+    left_disk:R -- L:junctionCenter
+    top_disk:B -- T:junctionCenter
+    bottom_disk:T -- B:junctionCenter
+    junctionCenter:R -- L:junctionRight
+    top_gateway:B -- T:junctionRight
+    bottom_gateway:T -- B:junctionRight
+```

doc/architecture/main.go

@@ -0,0 +1,107 @@
+//go:build linux || darwin
+
+// Package main is generating mermaid sequence diagram.
+package main
+
+import (
+	"io"
+	"os"
+
+	"github.com/nao1215/markdown"
+	"github.com/nao1215/markdown/mermaid/arch"
+)
+
+//go:generate go run main.go
+
+func main() {
+	f, err := os.Create("generated.md")
+	if err != nil {
+		panic(err)
+	}
+	defer f.Close()
+
+	diagram := arch.NewArchitecture(io.Discard).
+		Service("left_disk", arch.IconDisk, "Disk").
+		Service("top_disk", arch.IconDisk, "Disk").
+		Service("bottom_disk", arch.IconDisk, "Disk").
+		Service("top_gateway", arch.IconInternet, "Gateway").
+		Service("bottom_gateway", arch.IconInternet, "Gateway").
+		Junction("junctionCenter").
+		Junction("junctionRight").
+		LF().
+		Edges(
+			arch.Edge{
+				ServiceID: "left_disk",
+				Position:  arch.PositionRight,
+				Arrow:     arch.ArrowNone,
+			},
+			arch.Edge{
+				ServiceID: "junctionCenter",
+				Position:  arch.PositionLeft,
+				Arrow:     arch.ArrowNone,
+			}).
+		Edges(
+			arch.Edge{
+				ServiceID: "top_disk",
+				Position:  arch.PositionBottom,
+				Arrow:     arch.ArrowNone,
+			},
+			arch.Edge{
+				ServiceID: "junctionCenter",
+				Position:  arch.PositionTop,
+				Arrow:     arch.ArrowNone,
+			}).
+		Edges(
+			arch.Edge{
+				ServiceID: "bottom_disk",
+				Position:  arch.PositionTop,
+				Arrow:     arch.ArrowNone,
+			},
+			arch.Edge{
+				ServiceID: "junctionCenter",
+				Position:  arch.PositionBottom,
+				Arrow:     arch.ArrowNone,
+			}).
+		Edges(
+			arch.Edge{
+				ServiceID: "junctionCenter",
+				Position:  arch.PositionRight,
+				Arrow:     arch.ArrowNone,
+			},
+			arch.Edge{
+				ServiceID: "junctionRight",
+				Position:  arch.PositionLeft,
+				Arrow:     arch.ArrowNone,
+			}).
+		Edges(
+			arch.Edge{
+				ServiceID: "top_gateway",
+				Position:  arch.PositionBottom,
+				Arrow:     arch.ArrowNone,
+			},
+			arch.Edge{
+				ServiceID: "junctionRight",
+				Position:  arch.PositionTop,
+				Arrow:     arch.ArrowNone,
+			}).
+		Edges(
+			arch.Edge{
+				ServiceID: "bottom_gateway",
+				Position:  arch.PositionTop,
+				Arrow:     arch.ArrowNone,
+			},
+			arch.Edge{
+				ServiceID: "junctionRight",
+				Position:  arch.PositionBottom,
+				Arrow:     arch.ArrowNone,
+			}).String() //nolint
+
+	err = markdown.NewMarkdown(f).
+		H2("Architecture Diagram").
+		CodeBlocks(markdown.SyntaxHighlightMermaid, diagram).
+		Build()
+
+	if err != nil {
+		panic(err)
+	}
+}

mermaid/arch/architecture.go

@@ -0,0 +1,66 @@
+// Package arch is mermaid architecture diagram builder.
+// The building blocks of an architecture are groups, services, edges, and junctions.
+// The arch package incorporates beta features of Mermaid, so the specifications are subject to significant changes.
+package arch
+
+import (
+	"fmt"
+	"io"
+	"strings"
+
+	"github.com/nao1215/markdown/internal"
+)
+
+// Architecture is a architecture diagram builder.
+type Architecture struct {
+	// body is architecture diagram body.
+	body []string
+	// config is the configuration for the architecture diagram.
+	config *config
+	// dest is output destination for architecture diagram body.
+	dest io.Writer
+	// err manages errors that occur in all parts of the architecture building.
+	err error
+}
+
+// NewArchitecture returns a new Architecture.
+func NewArchitecture(w io.Writer, opts ...Option) *Architecture {
+	c := newConfig()
+
+	for _, opt := range opts {
+		opt(c)
+	}
+
+	return &Architecture{
+		body:   []string{"architecture-beta"},
+		dest:   w,
+		config: c,
+	}
+}
+
+// String returns the architecture diagram body.
+func (a *Architecture) String() string {
+	return strings.Join(a.body, internal.LineFeed())
+}
+
+// Build writes the architecture diagram body to the output destination.
+func (a *Architecture) Build() error {
+	if _, err := a.dest.Write([]byte(a.String())); err != nil {
+		if a.err != nil {
+			return fmt.Errorf("failed to write: %w: %s", err, a.err.Error()) //nolint:wrapcheck
+		}
+		return fmt.Errorf("failed to write: %w", err)
+	}
+	return nil
+}
+
+// Error returns the error that occurred during the architecture diagram building.
+func (a *Architecture) Error() error {
+	return a.err
+}
+
+// LF add a line feed to the architecture diagram body.
+func (a *Architecture) LF() *Architecture {
+	a.body = append(a.body, "")
+	return a
+}