README: Cleanup examples to make them runnable and testable

README.md

@@ -111,56 +111,8 @@ For detailed installation docs, with alternative methods and examples for each O
 In addition to being a runnable CLI tool, D2 can also be used to produce diagrams from
 Go programs.
 
-```go
-import (
-  "context"
-  "io/ioutil"
-  "path/filepath"
-  "strings"
+For examples, see [./docs/examples/lib](./docs/examples/lib).
 
-  "oss.terrastruct.com/d2/d2compiler"
-  "oss.terrastruct.com/d2/d2exporter"
-  "oss.terrastruct.com/d2/d2layouts/d2dagrelayout"
-  "oss.terrastruct.com/d2/d2renderers/d2svg"
-  "oss.terrastruct.com/d2/d2renderers/textmeasure"
-  "oss.terrastruct.com/d2/d2themes/d2themescatalog"
-)
-
-func main() {
-  graph, _ := d2compiler.Compile("", strings.NewReader("x -> y"), &d2compiler.CompileOptions{UTF16: true})
-  ruler, _ := textmeasure.NewRuler()
-  graph.SetDimensions(nil, ruler)
-  d2dagrelayout.Layout(context.Background(), graph)
-  diagram, _ := d2exporter.Export(context.Background(), graph, d2themescatalog.NeutralDefault.ID)
-  out, _ := d2svg.Render(diagram)
-  ioutil.WriteFile(filepath.Join("out.svg"), out, 0600)
-}
-```
-
-D2 is built to be hackable -- the language has an API built on top of it to make edits
-programmatically. Modifying the above diagram:
-
-```go
-import (
-  "oss.terrastruct.com/d2/d2renderers/textmeasure"
-  "oss.terrastruct.com/d2/d2themes/d2themescatalog"
-)
-
-// Create a shape with the ID, "meow"
-graph, _, _ = d2oracle.Create(graph, "meow")
-// Style the shape green
-color := "green"
-graph, _ = d2oracle.Set(graph, "meow.style.fill", nil, &color)
-// Create a shape with the ID, "cat"
-graph, _, _ = d2oracle.Create(graph, "cat")
-// Move the shape "meow" inside the container "cat"
-graph, _ = d2oracle.Move(graph, "meow", "cat.meow")
-// Prints formatted D2 script
-println(d2format.Format(graph.AST))
-```
-
-This makes it easy to build functionality on top of D2. Terrastruct uses the above API to
-implement editing of D2 from mouse actions in a visual interface.
 
 ## Themes
 

ci/release/changelogs/next.md

@@ -26,7 +26,7 @@
 - `d2` now lives in the root folder of the repository instead of as a subcommand.
   So you can run `go install oss.terrastruct.com/d2@latest` to install from source
   now.
-  [#xxx](https://github.com/terrastruct/d2/pull/xxx)
+  [#290](https://github.com/terrastruct/d2/pull/290)
 
 #### Bugfixes 🔴
 

ci/sub

@@ -1 +1 @@
-Subproject commit 28fb67e3bf11d7df2be9ad57b67b78a1733a7f2d
+Subproject commit 0dacc9c6cee5b8d901f22f57e9dc7f9acf640cbc

d2lib/d2.go

@@ -22,7 +22,7 @@ type CompileOptions struct {
 	ThemeID int64
 }
 
-func Compile(ctx context.Context, input string, opts *CompileOptions) (*d2target.Diagram, error) {
+func Compile(ctx context.Context, input string, opts *CompileOptions) (*d2target.Diagram, *d2graph.Graph, error) {
 	if opts == nil {
 		opts = &CompileOptions{}
 	}
@@ -31,12 +31,12 @@ func Compile(ctx context.Context, input string, opts *CompileOptions) (*d2target
 		UTF16: opts.UTF16,
 	})
 	if err != nil {
-		return nil, err
+		return nil, nil, err
 	}
 
 	err = g.SetDimensions(opts.MeasuredTexts, opts.Ruler)
 	if err != nil {
-		return nil, err
+		return nil, nil, err
 	}
 
 	if opts.Layout != nil {
@@ -47,11 +47,11 @@ func Compile(ctx context.Context, input string, opts *CompileOptions) (*d2target
 		err = errors.New("no available layout")
 	}
 	if err != nil {
-		return nil, err
+		return nil, nil, err
 	}
 
 	diagram, err := d2exporter.Export(ctx, g, opts.ThemeID)
-	return diagram, err
+	return diagram, g, err
 }
 
 // See c.go

docs/examples/lib/1-d2lib/.gitignore

@@ -0,0 +1 @@
+out.svg

docs/examples/lib/1-d2lib/d2lib.go

@@ -0,0 +1,25 @@
+package main
+
+import (
+	"context"
+	"io/ioutil"
+	"path/filepath"
+
+	"oss.terrastruct.com/d2/d2layouts/d2dagrelayout"
+	"oss.terrastruct.com/d2/d2lib"
+	"oss.terrastruct.com/d2/d2renderers/d2svg"
+	"oss.terrastruct.com/d2/d2renderers/textmeasure"
+	"oss.terrastruct.com/d2/d2themes/d2themescatalog"
+)
+
+// Remember to add if err != nil checks in production.
+func main() {
+	ruler, _ := textmeasure.NewRuler()
+	diagram, _, _ := d2lib.Compile(context.Background(), "x -> y", &d2lib.CompileOptions{
+		Layout:  d2dagrelayout.Layout,
+		Ruler:   ruler,
+		ThemeID: d2themescatalog.GrapeSoda.ID,
+	})
+	out, _ := d2svg.Render(diagram)
+	_ = ioutil.WriteFile(filepath.Join("out.svg"), out, 0600)
+}

docs/examples/lib/1-d2lib/d2lib_test.go

@@ -0,0 +1,9 @@
+package main
+
+import (
+	"testing"
+)
+
+func TestMain_(t *testing.T) {
+	main()
+}

docs/examples/lib/2-d2oracle/d2oracle.go

@@ -0,0 +1,36 @@
+package main
+
+import (
+	"context"
+	"fmt"
+
+	"oss.terrastruct.com/d2/d2format"
+	"oss.terrastruct.com/d2/d2layouts/d2dagrelayout"
+	"oss.terrastruct.com/d2/d2lib"
+	"oss.terrastruct.com/d2/d2oracle"
+	"oss.terrastruct.com/d2/d2renderers/textmeasure"
+	"oss.terrastruct.com/d2/d2themes/d2themescatalog"
+)
+
+// Remember to add if err != nil checks in production.
+func main() {
+	// From one.go
+	ruler, _ := textmeasure.NewRuler()
+	_, graph, _ := d2lib.Compile(context.Background(), "x -> y", &d2lib.CompileOptions{
+		Layout:  d2dagrelayout.Layout,
+		Ruler:   ruler,
+		ThemeID: d2themescatalog.GrapeSoda.ID,
+	})
+
+	// Create a shape with the ID, "meow"
+	graph, _, _ = d2oracle.Create(graph, "meow")
+	// Style the shape green
+	color := "green"
+	graph, _ = d2oracle.Set(graph, "meow.style.fill", nil, &color)
+	// Create a shape with the ID, "cat"
+	graph, _, _ = d2oracle.Create(graph, "cat")
+	// Move the shape "meow" inside the container "cat"
+	graph, _ = d2oracle.Move(graph, "meow", "cat.meow")
+	// Prints formatted D2 script
+	fmt.Print(d2format.Format(graph.AST))
+}

docs/examples/lib/2-d2oracle/d2oracle_test.go

@@ -0,0 +1,9 @@
+package main
+
+import (
+	"testing"
+)
+
+func TestMain_(t *testing.T) {
+	main()
+}

docs/examples/lib/3-lowlevel/.gitignore

@@ -0,0 +1 @@
+out.svg

docs/examples/lib/3-lowlevel/lowlevel.go

@@ -0,0 +1,26 @@
+package main
+
+import (
+	"context"
+	"io/ioutil"
+	"path/filepath"
+	"strings"
+
+	"oss.terrastruct.com/d2/d2compiler"
+	"oss.terrastruct.com/d2/d2exporter"
+	"oss.terrastruct.com/d2/d2layouts/d2dagrelayout"
+	"oss.terrastruct.com/d2/d2renderers/d2svg"
+	"oss.terrastruct.com/d2/d2renderers/textmeasure"
+	"oss.terrastruct.com/d2/d2themes/d2themescatalog"
+)
+
+// Remember to add if err != nil checks in production.
+func main() {
+	graph, _ := d2compiler.Compile("", strings.NewReader("x -> y"), nil)
+	ruler, _ := textmeasure.NewRuler()
+	_ = graph.SetDimensions(nil, ruler)
+	_ = d2dagrelayout.Layout(context.Background(), graph)
+	diagram, _ := d2exporter.Export(context.Background(), graph, d2themescatalog.NeutralDefault.ID)
+	out, _ := d2svg.Render(diagram)
+	_ = ioutil.WriteFile(filepath.Join("out.svg"), out, 0600)
+}

docs/examples/lib/3-lowlevel/lowlevel_test.go

@@ -0,0 +1,9 @@
+package main
+
+import (
+	"testing"
+)
+
+func TestMain_(t *testing.T) {
+	main()
+}

docs/examples/lib/README.md

@@ -0,0 +1,30 @@
+# D2 library examples
+
+We have a few examples in this directory on how to use the D2 library to turn D2 scripts
+into rendered svg diagrams and more.
+
+Each example is runnable though does not include error handling for readability.
+
+### [./1-d2lib](./1-d2lib)
+
+A minimal example showing you how to compile the diagram `x -> y` into an svg.
+
+### [./2-d2oracle](./2-d2oracle)
+
+D2 is built to be hackable -- the language has an API built on top of it to make edits
+programmatically.
+
+Modifying the previous example, this example demonstrates how
+[d2oracle](../../../d2oracle) can be used to create a new shape, style it programatically
+and then output the modified d2 script.
+
+This makes it easy to build functionality on top of D2. Terrastruct uses the
+[d2oracle](../../../d2oracle) API to implement editing of D2 from mouse actions in a
+visual interface.
+
+### [./3-lowlevel](./3-lowlevel)
+
+`d2lib` from the first example is just a wrapper around the lower level APIs. They
+can be used directly and this example demonstrates such usage.
+
+This shouldn't be necessary for most usecases.

e2etests/e2e_test.go

@@ -19,7 +19,7 @@ import (
 	"oss.terrastruct.com/d2/d2graph"
 	"oss.terrastruct.com/d2/d2layouts/d2dagrelayout"
 	"oss.terrastruct.com/d2/d2layouts/d2elklayout"
-	d2 "oss.terrastruct.com/d2/d2lib"
+	"oss.terrastruct.com/d2/d2lib"
 	"oss.terrastruct.com/d2/d2renderers/d2svg"
 	"oss.terrastruct.com/d2/d2renderers/textmeasure"
 	"oss.terrastruct.com/d2/d2target"
@@ -104,7 +104,7 @@ func run(t *testing.T, tc testCase) {
 		} else if layoutName == "elk" {
 			layout = d2elklayout.Layout
 		}
-		diagram, err := d2.Compile(ctx, tc.script, &d2.CompileOptions{
+		diagram, _, err := d2lib.Compile(ctx, tc.script, &d2lib.CompileOptions{
 			UTF16:   true,
 			Ruler:   ruler,
 			ThemeID: 0,

main.go

@@ -15,7 +15,7 @@ import (
 	"go.uber.org/multierr"
 
 	"oss.terrastruct.com/d2/d2layouts/d2sequence"
-	d2 "oss.terrastruct.com/d2/d2lib"
+	"oss.terrastruct.com/d2/d2lib"
 	"oss.terrastruct.com/d2/d2plugin"
 	"oss.terrastruct.com/d2/d2renderers/d2svg"
 	"oss.terrastruct.com/d2/d2renderers/textmeasure"
@@ -196,7 +196,7 @@ func compile(ctx context.Context, ms *xmain.State, plugin d2plugin.Plugin, theme
 	if os.Getenv("D2_SEQUENCE") == "1" {
 		layout = d2sequence.Layout
 	}
-	d, err := d2.Compile(ctx, string(input), &d2.CompileOptions{
+	diagram, _, err := d2lib.Compile(ctx, string(input), &d2lib.CompileOptions{
 		Layout:  layout,
 		Ruler:   ruler,
 		ThemeID: themeID,
@@ -205,7 +205,7 @@ func compile(ctx context.Context, ms *xmain.State, plugin d2plugin.Plugin, theme
 		return nil, false, err
 	}
 
-	svg, err := d2svg.Render(d)
+	svg, err := d2svg.Render(diagram)
 	if err != nil {
 		return nil, false, err
 	}