Merge pull request #114 from planetlabs/extensions

Core types and extensions

Author: tschaub

asset.go

@@ -0,0 +1,50 @@
+package stac
+
+import (
+	"encoding/json"
+	"fmt"
+
+	"github.com/mitchellh/mapstructure"
+)
+
+type Asset struct {
+	Type        string           `json:"type,omitempty"`
+	Href        string           `json:"href"`
+	Title       string           `json:"title,omitempty"`
+	Description string           `json:"description,omitempty"`
+	Created     string           `json:"created,omitempty"`
+	Roles       []string         `json:"roles,omitempty"`
+	Extensions  []AssetExtension `json:"-"`
+}
+
+var _ json.Marshaler = (*Asset)(nil)
+
+type AssetExtension interface {
+	Apply(*Asset)
+	URI() string
+}
+
+func (asset Asset) MarshalJSON() ([]byte, error) {
+	assetMap := map[string]any{}
+	decoder, decoderErr := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
+		TagName: "json",
+		Result:  &assetMap,
+	})
+	if decoderErr != nil {
+		return nil, decoderErr
+	}
+
+	decodeErr := decoder.Decode(asset)
+	if decodeErr != nil {
+		return nil, decodeErr
+	}
+
+	for _, extension := range asset.Extensions {
+		extension.Apply(&asset)
+		if decodeErr := decoder.Decode(extension); decodeErr != nil {
+			return nil, fmt.Errorf("trouble encoding JSON for %s asset: %w", extension.URI(), decodeErr)
+		}
+	}
+
+	return json.Marshal(assetMap)
+}

asset_test.go

@@ -0,0 +1,57 @@
+package stac_test
+
+import (
+	"encoding/json"
+	"testing"
+
+	"github.com/planetlabs/go-stac"
+	"github.com/planetlabs/go-stac/extensions/pl"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestAssetMarshal(t *testing.T) {
+	asset := &stac.Asset{
+		Title: "An Image",
+		Href:  "https://example.com/image.tif",
+		Type:  "image/tiff",
+		Roles: []string{"data", "reflectance"},
+	}
+
+	data, err := json.Marshal(asset)
+	require.Nil(t, err)
+
+	expected := `{
+		"title": "An Image",
+		"href": "https://example.com/image.tif",
+		"type": "image/tiff",
+		"roles": ["data", "reflectance"]
+	}`
+
+	assert.JSONEq(t, expected, string(data))
+}
+
+func TestAssetExtendedMarshal(t *testing.T) {
+	asset := &stac.Asset{
+		Href: "https://example.com/image.tif",
+		Type: "image/tiff",
+		Extensions: []stac.AssetExtension{
+			&pl.Asset{
+				AssetType:  "ortho_analytic_4b_sr",
+				BundleType: "analytic_sr_udm2",
+			},
+		},
+	}
+
+	data, err := json.Marshal(asset)
+	require.Nil(t, err)
+
+	expected := `{
+		"href": "https://example.com/image.tif",
+		"type": "image/tiff",
+		"pl:asset_type": "ortho_analytic_4b_sr",
+		"pl:bundle_type": "analytic_sr_udm2"
+	}`
+
+	assert.JSONEq(t, expected, string(data))
+}

catalog.go

@@ -0,0 +1,38 @@
+package stac
+
+import (
+	"encoding/json"
+
+	"github.com/mitchellh/mapstructure"
+)
+
+type Catalog struct {
+	Version     string   `json:"stac_version"`
+	Id          string   `json:"id"`
+	Title       string   `json:"title,omitempty"`
+	Description string   `json:"description"`
+	Links       []*Link  `json:"links"`
+	ConformsTo  []string `json:"conformsTo,omitempty"`
+}
+
+var _ json.Marshaler = (*Catalog)(nil)
+
+func (catalog Catalog) MarshalJSON() ([]byte, error) {
+	collectionMap := map[string]any{
+		"type": "Catalog",
+	}
+	decoder, decoderErr := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
+		TagName: "json",
+		Result:  &collectionMap,
+	})
+	if decoderErr != nil {
+		return nil, decoderErr
+	}
+
+	decodeErr := decoder.Decode(catalog)
+	if decodeErr != nil {
+		return nil, decodeErr
+	}
+
+	return json.Marshal(collectionMap)
+}

catalog_test.go

@@ -0,0 +1,40 @@
+package stac_test
+
+import (
+	"encoding/json"
+	"testing"
+
+	"github.com/planetlabs/go-stac"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestCatalogMarshal(t *testing.T) {
+	catalog := &stac.Catalog{
+		Version:     "1.0.0",
+		Id:          "catalog-id",
+		Description: "Test Catalog",
+		Links: []*stac.Link{
+			{Href: "https://example.com/stac/catalog", Rel: "self", Type: "application/json"},
+		},
+	}
+
+	data, err := json.Marshal(catalog)
+	require.Nil(t, err)
+
+	expected := `{
+		"type": "Catalog",
+		"id": "catalog-id",
+		"description": "Test Catalog",
+		"links": [
+			{
+				"href": "https://example.com/stac/catalog",
+				"rel": "self",
+				"type": "application/json"
+			}
+		],
+		"stac_version": "1.0.0"
+	}`
+
+	assert.JSONEq(t, expected, string(data))
+}

collection.go

@@ -0,0 +1,68 @@
+package stac
+
+import (
+	"encoding/json"
+
+	"github.com/mitchellh/mapstructure"
+)
+
+type Collection struct {
+	Version     string            `json:"stac_version"`
+	Id          string            `json:"id"`
+	Title       string            `json:"title,omitempty"`
+	Description string            `json:"description"`
+	Keywords    []string          `json:"keywords,omitempty"`
+	License     string            `json:"license"`
+	Providers   []*Provider       `json:"providers,omitempty"`
+	Extent      *Extent           `json:"extent"`
+	Summaries   map[string]any    `json:"summaries,omitempty"`
+	Links       []*Link           `json:"links"`
+	Assets      map[string]*Asset `json:"assets,omitempty"`
+}
+
+type Provider struct {
+	Name        string   `json:"name"`
+	Description string   `json:"description,omitempty"`
+	Roles       []string `json:"roles,omitempty"`
+	Url         string   `json:"url,omitempty"`
+}
+
+type Extent struct {
+	Spatial  *SpatialExtent  `json:"spatial,omitempty"`
+	Temporal *TemporalExtent `json:"temporal,omitempty"`
+}
+
+type SpatialExtent struct {
+	Bbox [][]float64 `json:"bbox"`
+}
+
+type TemporalExtent struct {
+	Interval [][]any `json:"interval"`
+}
+
+var _ json.Marshaler = (*Collection)(nil)
+
+func (collection Collection) MarshalJSON() ([]byte, error) {
+	collectionMap := map[string]any{
+		"type": "Collection",
+	}
+	decoder, decoderErr := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
+		TagName: "json",
+		Result:  &collectionMap,
+	})
+	if decoderErr != nil {
+		return nil, decoderErr
+	}
+
+	decodeErr := decoder.Decode(collection)
+	if decodeErr != nil {
+		return nil, decodeErr
+	}
+
+	return json.Marshal(collectionMap)
+}
+
+type CollectionsList struct {
+	Collections []*Collection `json:"collections"`
+	Links       []*Link       `json:"links"`
+}

collection_test.go

@@ -0,0 +1,54 @@
+package stac_test
+
+import (
+	"encoding/json"
+	"testing"
+
+	"github.com/planetlabs/go-stac"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestCollectionMarshal(t *testing.T) {
+	collection := &stac.Collection{
+		Version:     "1.0.0",
+		Id:          "collection-id",
+		Description: "Test Collection",
+		License:     "various",
+		Links: []*stac.Link{
+			{Href: "https://example.com/stac/collections/collection-id", Rel: "self", Type: "application/json"},
+		},
+		Extent: &stac.Extent{
+			Spatial: &stac.SpatialExtent{
+				Bbox: [][]float64{{-180, -90, 180, 90}},
+			},
+		},
+	}
+
+	data, err := json.Marshal(collection)
+	require.Nil(t, err)
+
+	expected := `{
+		"type": "Collection",
+		"id": "collection-id",
+		"description": "Test Collection",
+		"extent": {
+			"spatial": {
+				"bbox": [
+					[-180, -90, 180, 90]
+				]
+			}
+		},
+		"license": "various",
+		"links": [
+			{
+				"href": "https://example.com/stac/collections/collection-id",
+				"rel": "self",
+				"type": "application/json"
+			}
+		],
+		"stac_version": "1.0.0"
+	}`
+
+	assert.JSONEq(t, expected, string(data))
+}

extensions/pl/pl.go

@@ -0,0 +1,39 @@
+package pl
+
+import "github.com/planetlabs/go-stac"
+
+const extensionUri = "https://planetlabs.github.io/stac-extension/v1.0.0-beta.1/schema.json"
+
+type Asset struct {
+	AssetType  string `json:"pl:asset_type,omitempty"`
+	BundleType string `json:"pl:bundle_type,omitempty"`
+}
+
+var _ stac.AssetExtension = (*Asset)(nil)
+
+func (*Asset) URI() string {
+	return extensionUri
+}
+
+func (*Asset) Apply(*stac.Asset) {}
+
+type Item struct {
+	ItemType           string   `json:"pl:item_type,omitempty"`
+	PixelResolution    float64  `json:"pl:pixel_resolution,omitempty"`
+	PublishingStage    string   `json:"pl:publishing_stage,omitempty"`
+	QualityCategory    string   `json:"pl:quality_category,omitempty"`
+	StripId            string   `json:"pl:strip_id,omitempty"`
+	BlackFill          *float64 `json:"pl:black_fill,omitempty"`
+	ClearPercent       *float64 `json:"pl:clear_percent,omitempty"`
+	GridCell           *int     `json:"pl:grid_cell,omitempty"`
+	GroundControl      *bool    `json:"pl:ground_control,omitempty"`
+	GroundControlRatio *float64 `json:"pl:ground_control_ratio,omitempty"`
+}
+
+var _ stac.ItemExtension = (*Item)(nil)
+
+func (*Item) URI() string {
+	return extensionUri
+}
+
+func (*Item) Apply(*stac.Item) {}