Overhaul structs, refactor JSON parser and saver

Signed-off-by: Ian Ling <ian@iancaling.com>

10 files changed, 528 insertions, 323 deletions

diff --git a/spdx/annotation.go b/spdx/annotation.go
index ede9c8a..560b6f0 100644
--- a/spdx/annotation.go
+++ b/spdx/annotation.go
@@ -2,54 +2,91 @@
 
 package spdx
 
-// Annotation2_1 is an Annotation section of an SPDX Document for version 2.1 of the spec.
-type Annotation2_1 struct {
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+)
 
-	// 8.1: Annotator
-	// Cardinality: conditional (mandatory, one) if there is an Annotation
+type Annotator struct {
 	Annotator string
 	// including AnnotatorType: one of "Person", "Organization" or "Tool"
 	AnnotatorType string
+}
+
+// UnmarshalJSON takes an annotator in the typical one-line format and parses it into an Annotator struct.
+// This function is also used when unmarshalling YAML
+func (a *Annotator) UnmarshalJSON(data []byte) error {
+	// annotator will simply be a string
+	annotatorStr := string(data)
+	annotatorStr = strings.Trim(annotatorStr, "\"")
+
+	annotatorFields := strings.SplitN(annotatorStr, ": ", 2)
+
+	if len(annotatorFields) != 2 {
+		return fmt.Errorf("failed to parse Annotator '%s'", annotatorStr)
+	}
+
+	a.AnnotatorType = annotatorFields[0]
+	a.Annotator = annotatorFields[1]
+
+	return nil
+}
+
+// MarshalJSON converts the receiver into a slice of bytes representing an Annotator in string form.
+// This function is also used when marshalling to YAML
+func (a Annotator) MarshalJSON() ([]byte, error) {
+	if a.Annotator != "" {
+		return json.Marshal(fmt.Sprintf("%s: %s", a.AnnotatorType, a.Annotator))
+	}
+
+	return []byte{}, nil
+}
+
+// Annotation2_1 is an Annotation section of an SPDX Document for version 2.1 of the spec.
+type Annotation2_1 struct {
+	// 8.1: Annotator
+	// Cardinality: conditional (mandatory, one) if there is an Annotation
+	Annotator Annotator `json:"annotator"`
 
 	// 8.2: Annotation Date: YYYY-MM-DDThh:mm:ssZ
 	// Cardinality: conditional (mandatory, one) if there is an Annotation
-	AnnotationDate string
+	AnnotationDate string `json:"annotationDate"`
 
 	// 8.3: Annotation Type: "REVIEW" or "OTHER"
 	// Cardinality: conditional (mandatory, one) if there is an Annotation
-	AnnotationType string
+	AnnotationType string `json:"annotationType"`
 
 	// 8.4: SPDX Identifier Reference
 	// Cardinality: conditional (mandatory, one) if there is an Annotation
-	AnnotationSPDXIdentifier DocElementID
+	// This field is not used in hierarchical data formats where the referenced element is clear, such as JSON or YAML.
+	AnnotationSPDXIdentifier DocElementID `json:"-"`
 
 	// 8.5: Annotation Comment
 	// Cardinality: conditional (mandatory, one) if there is an Annotation
-	AnnotationComment string
+	AnnotationComment string `json:"comment"`
 }
 
 // Annotation2_2 is an Annotation section of an SPDX Document for version 2.2 of the spec.
 type Annotation2_2 struct {
-
 	// 8.1: Annotator
 	// Cardinality: conditional (mandatory, one) if there is an Annotation
-	Annotator string
-	// including AnnotatorType: one of "Person", "Organization" or "Tool"
-	AnnotatorType string
+	Annotator Annotator `json:"annotator"`
 
 	// 8.2: Annotation Date: YYYY-MM-DDThh:mm:ssZ
 	// Cardinality: conditional (mandatory, one) if there is an Annotation
-	AnnotationDate string
+	AnnotationDate string `json:"annotationDate"`
 
 	// 8.3: Annotation Type: "REVIEW" or "OTHER"
 	// Cardinality: conditional (mandatory, one) if there is an Annotation
-	AnnotationType string
+	AnnotationType string `json:"annotationType"`
 
 	// 8.4: SPDX Identifier Reference
 	// Cardinality: conditional (mandatory, one) if there is an Annotation
-	AnnotationSPDXIdentifier DocElementID
+	// This field is not used in hierarchical data formats where the referenced element is clear, such as JSON or YAML.
+	AnnotationSPDXIdentifier DocElementID `json:"-"`
 
 	// 8.5: Annotation Comment
 	// Cardinality: conditional (mandatory, one) if there is an Annotation
-	AnnotationComment string
+	AnnotationComment string `json:"comment"`
 }
diff --git a/spdx/checksum.go b/spdx/checksum.go
index 872aee2..3295969 100644
--- a/spdx/checksum.go
+++ b/spdx/checksum.go
@@ -2,25 +2,25 @@
 
 package spdx
 
-// ChecksumAlgorithm2_2 represents the algorithm used to generate the file checksum in the Checksum2_2 struct.
+// ChecksumAlgorithm represents the algorithm used to generate the file checksum in the Checksum struct.
 type ChecksumAlgorithm string
 
 // The checksum algorithms mentioned in the spdxv2.2.0 https://spdx.github.io/spdx-spec/4-file-information/#44-file-checksum
 const (
 	SHA224 ChecksumAlgorithm = "SHA224"
-	SHA1                     = "SHA1"
-	SHA256                   = "SHA256"
-	SHA384                   = "SHA384"
-	SHA512                   = "SHA512"
-	MD2                      = "MD2"
-	MD4                      = "MD4"
-	MD5                      = "MD5"
-	MD6                      = "MD6"
+	SHA1   ChecksumAlgorithm = "SHA1"
+	SHA256 ChecksumAlgorithm = "SHA256"
+	SHA384 ChecksumAlgorithm = "SHA384"
+	SHA512 ChecksumAlgorithm = "SHA512"
+	MD2    ChecksumAlgorithm = "MD2"
+	MD4    ChecksumAlgorithm = "MD4"
+	MD5    ChecksumAlgorithm = "MD5"
+	MD6    ChecksumAlgorithm = "MD6"
 )
 
-//Checksum2_2 struct Provide a unique identifier to match analysis information on each specific file in a package.
-// The Algorithm field describes the ChecksumAlgorithm2_2 used and the Value represents the file checksum
+// Checksum provides a unique identifier to match analysis information on each specific file in a package.
+// The Algorithm field describes the ChecksumAlgorithm used and the Value represents the file checksum
 type Checksum struct {
-	Algorithm ChecksumAlgorithm
-	Value     string
+	Algorithm ChecksumAlgorithm `json:"algorithm"`
+	Value     string            `json:"checksumValue"`
 }
diff --git a/spdx/creation_info.go b/spdx/creation_info.go
index 1bdaaab..c0b6f63 100644
--- a/spdx/creation_info.go
+++ b/spdx/creation_info.go
@@ -2,146 +2,85 @@
 
 package spdx
 
-// CreationInfo2_1 is a Document Creation Information section of an
-// SPDX Document for version 2.1 of the spec.
-type CreationInfo2_1 struct {
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+)
+
+// Creator is a wrapper around the Creator SPDX field. The SPDX field contains two values, which requires special
+// handling in order to marshal/unmarshal it to/from Go data types.
+type Creator struct {
+	Creator string
+	// CreatorType should be one of "Person", "Organization", or "Tool"
+	CreatorType string
+}
 
-	// 2.1: SPDX Version; should be in the format "SPDX-2.1"
-	// Cardinality: mandatory, one
-	SPDXVersion string
+// UnmarshalJSON takes an annotator in the typical one-line format and parses it into a Creator struct.
+// This function is also used when unmarshalling YAML
+func (c *Creator) UnmarshalJSON(data []byte) error {
+	str := string(data)
+	str = strings.Trim(str, "\"")
+	fields := strings.SplitN(str, ": ", 2)
 
-	// 2.2: Data License; should be "CC0-1.0"
-	// Cardinality: mandatory, one
-	DataLicense string
+	if len(fields) != 2 {
+		return fmt.Errorf("failed to parse Creator '%s'", str)
+	}
 
-	// 2.3: SPDX Identifier; should be "DOCUMENT" to represent
-	//      mandatory identifier of SPDXRef-DOCUMENT
-	// Cardinality: mandatory, one
-	SPDXIdentifier ElementID
+	c.CreatorType = fields[0]
+	c.Creator = fields[1]
 
-	// 2.4: Document Name
-	// Cardinality: mandatory, one
-	DocumentName string
+	return nil
+}
 
-	// 2.5: Document Namespace
-	// Cardinality: mandatory, one
-	DocumentNamespace string
+// MarshalJSON converts the receiver into a slice of bytes representing a Creator in string form.
+// This function is also used with marshalling to YAML
+func (c Creator) MarshalJSON() ([]byte, error) {
+	if c.Creator != "" {
+		return json.Marshal(fmt.Sprintf("%s: %s", c.CreatorType, c.Creator))
+	}
 
-	// 2.6: External Document References
-	// Cardinality: optional, one or many
-	ExternalDocumentReferences map[string]ExternalDocumentRef2_1
+	return []byte{}, nil
+}
 
+// CreationInfo2_1 is a Document Creation Information section of an
+// SPDX Document for version 2.1 of the spec.
+type CreationInfo2_1 struct {
 	// 2.7: License List Version
 	// Cardinality: optional, one
-	LicenseListVersion string
+	LicenseListVersion string `json:"licenseListVersion"`
 
 	// 2.8: Creators: may have multiple keys for Person, Organization
 	//      and/or Tool
 	// Cardinality: mandatory, one or many
-	CreatorPersons       []string
-	CreatorOrganizations []string
-	CreatorTools         []string
+	Creators []Creator `json:"creators"`
 
 	// 2.9: Created: data format YYYY-MM-DDThh:mm:ssZ
 	// Cardinality: mandatory, one
-	Created string
+	Created string `json:"created"`
 
 	// 2.10: Creator Comment
 	// Cardinality: optional, one
-	CreatorComment string
-
-	// 2.11: Document Comment
-	// Cardinality: optional, one
-	DocumentComment string
-}
-
-// ExternalDocumentRef2_1 is a reference to an external SPDX document
-// as defined in section 2.6 for version 2.1 of the spec.
-type ExternalDocumentRef2_1 struct {
-
-	// DocumentRefID is the ID string defined in the start of the
-	// reference. It should _not_ contain the "DocumentRef-" part
-	// of the mandatory ID string.
-	DocumentRefID string
-
-	// URI is the URI defined for the external document
-	URI string
-
-	// Alg is the type of hash algorithm used, e.g. "SHA1", "SHA256"
-	Alg string
-
-	// Checksum is the actual hash data
-	Checksum string
+	CreatorComment string `json:"comment"`
 }
 
 // CreationInfo2_2 is a Document Creation Information section of an
 // SPDX Document for version 2.2 of the spec.
 type CreationInfo2_2 struct {
-
-	// 2.1: SPDX Version; should be in the format "SPDX-2.2"
-	// Cardinality: mandatory, one
-	SPDXVersion string
-
-	// 2.2: Data License; should be "CC0-1.0"
-	// Cardinality: mandatory, one
-	DataLicense string
-
-	// 2.3: SPDX Identifier; should be "DOCUMENT" to represent
-	//      mandatory identifier of SPDXRef-DOCUMENT
-	// Cardinality: mandatory, one
-	SPDXIdentifier ElementID
-
-	// 2.4: Document Name
-	// Cardinality: mandatory, one
-	DocumentName string
-
-	// 2.5: Document Namespace
-	// Cardinality: mandatory, one
-	DocumentNamespace string
-
-	// 2.6: External Document References
-	// Cardinality: optional, one or many
-	ExternalDocumentReferences map[string]ExternalDocumentRef2_2
-
 	// 2.7: License List Version
 	// Cardinality: optional, one
-	LicenseListVersion string
+	LicenseListVersion string `json:"licenseListVersion"`
 
 	// 2.8: Creators: may have multiple keys for Person, Organization
 	//      and/or Tool
 	// Cardinality: mandatory, one or many
-	CreatorPersons       []string
-	CreatorOrganizations []string
-	CreatorTools         []string
+	Creators []Creator `json:"creators"`
 
 	// 2.9: Created: data format YYYY-MM-DDThh:mm:ssZ
 	// Cardinality: mandatory, one
-	Created string
+	Created string `json:"created"`
 
 	// 2.10: Creator Comment
 	// Cardinality: optional, one
-	CreatorComment string
-
-	// 2.11: Document Comment
-	// Cardinality: optional, one
-	DocumentComment string
-}
-
-// ExternalDocumentRef2_2 is a reference to an external SPDX document
-// as defined in section 2.6 for version 2.2 of the spec.
-type ExternalDocumentRef2_2 struct {
-
-	// DocumentRefID is the ID string defined in the start of the
-	// reference. It should _not_ contain the "DocumentRef-" part
-	// of the mandatory ID string.
-	DocumentRefID string
-
-	// URI is the URI defined for the external document
-	URI string
-
-	// Alg is the type of hash algorithm used, e.g. "SHA1", "SHA256"
-	Alg string
-
-	// Checksum is the actual hash data
-	Checksum string
+	CreatorComment string `json:"comment"`
 }
diff --git a/spdx/document.go b/spdx/document.go
index 6a7bc3d..a3117cb 100644
--- a/spdx/document.go
+++ b/spdx/document.go
@@ -3,15 +3,75 @@
 // SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
 package spdx
 
+// ExternalDocumentRef2_1 is a reference to an external SPDX document
+// as defined in section 2.6 for version 2.1 of the spec.
+type ExternalDocumentRef2_1 struct {
+	// DocumentRefID is the ID string defined in the start of the
+	// reference. It should _not_ contain the "DocumentRef-" part
+	// of the mandatory ID string.
+	DocumentRefID string `json:"externalDocumentId"`
+
+	// URI is the URI defined for the external document
+	URI string `json:"spdxDocument"`
+
+	// Checksum is the actual hash data
+	Checksum Checksum `json:"checksum"`
+}
+
+// ExternalDocumentRef2_2 is a reference to an external SPDX document
+// as defined in section 2.6 for version 2.2 of the spec.
+type ExternalDocumentRef2_2 struct {
+	// DocumentRefID is the ID string defined in the start of the
+	// reference. It should _not_ contain the "DocumentRef-" part
+	// of the mandatory ID string.
+	DocumentRefID string `json:"externalDocumentId"`
+
+	// URI is the URI defined for the external document
+	URI string `json:"spdxDocument"`
+
+	// Checksum is the actual hash data
+	Checksum Checksum `json:"checksum"`
+}
+
 // Document2_1 is an SPDX Document for version 2.1 of the spec.
 // See https://spdx.org/sites/cpstandard/files/pages/files/spdxversion2.1.pdf
 type Document2_1 struct {
-	CreationInfo    *CreationInfo2_1
-	Packages        map[ElementID]*Package2_1
-	UnpackagedFiles map[ElementID]*File2_1
-	OtherLicenses   []*OtherLicense2_1
-	Relationships   []*Relationship2_1
-	Annotations     []*Annotation2_1
+	// 2.1: SPDX Version; should be in the format "SPDX-2.1"
+	// Cardinality: mandatory, one
+	SPDXVersion string `json:"spdxVersion"`
+
+	// 2.2: Data License; should be "CC0-1.0"
+	// Cardinality: mandatory, one
+	DataLicense string `json:"dataLicense"`
+
+	// 2.3: SPDX Identifier; should be "DOCUMENT" to represent
+	//      mandatory identifier of SPDXRef-DOCUMENT
+	// Cardinality: mandatory, one
+	SPDXIdentifier ElementID `json:"SPDXID"`
+
+	// 2.4: Document Name
+	// Cardinality: mandatory, one
+	DocumentName string `json:"name"`
+
+	// 2.5: Document Namespace
+	// Cardinality: mandatory, one
+	DocumentNamespace string `json:"documentNamespace"`
+
+	// 2.6: External Document References
+	// Cardinality: optional, one or many
+	ExternalDocumentReferences []ExternalDocumentRef2_1 `json:"externalDocumentRefs,omitempty"`
+
+	// 2.11: Document Comment
+	// Cardinality: optional, one
+	DocumentComment string `json:"comment,omitempty"`
+
+	CreationInfo  *CreationInfo2_1   `json:"creationInfo"`
+	Packages      []*Package2_1      `json:"packages"`
+	Files         []*File2_1         `json:"files"`
+	OtherLicenses []*OtherLicense2_1 `json:"hasExtractedLicensingInfos"`
+	Relationships []*Relationship2_1 `json:"relationships"`
+	Annotations   []*Annotation2_1   `json:"annotations"`
+	Snippets      []Snippet2_1       `json:"snippets"`
 
 	// DEPRECATED in version 2.0 of spec
 	Reviews []*Review2_1
@@ -20,12 +80,42 @@ type Document2_1 struct {
 // Document2_2 is an SPDX Document for version 2.2 of the spec.
 // See https://spdx.github.io/spdx-spec/v2-draft/ (DRAFT)
 type Document2_2 struct {
-	CreationInfo    *CreationInfo2_2
-	Packages        map[ElementID]*Package2_2
-	UnpackagedFiles map[ElementID]*File2_2
-	OtherLicenses   []*OtherLicense2_2
-	Relationships   []*Relationship2_2
-	Annotations     []*Annotation2_2
+	// 2.1: SPDX Version; should be in the format "SPDX-2.2"
+	// Cardinality: mandatory, one
+	SPDXVersion string `json:"spdxVersion"`
+
+	// 2.2: Data License; should be "CC0-1.0"
+	// Cardinality: mandatory, one
+	DataLicense string `json:"dataLicense"`
+
+	// 2.3: SPDX Identifier; should be "DOCUMENT" to represent
+	//      mandatory identifier of SPDXRef-DOCUMENT
+	// Cardinality: mandatory, one
+	SPDXIdentifier ElementID `json:"SPDXID"`
+
+	// 2.4: Document Name
+	// Cardinality: mandatory, one
+	DocumentName string `json:"name"`
+
+	// 2.5: Document Namespace
+	// Cardinality: mandatory, one
+	DocumentNamespace string `json:"documentNamespace"`
+
+	// 2.6: External Document References
+	// Cardinality: optional, one or many
+	ExternalDocumentReferences []ExternalDocumentRef2_2 `json:"externalDocumentRefs,omitempty"`
+
+	// 2.11: Document Comment
+	// Cardinality: optional, one
+	DocumentComment string `json:"comment,omitempty"`
+
+	CreationInfo  *CreationInfo2_2   `json:"creationInfo"`
+	Packages      []*Package2_2      `json:"packages"`
+	Files         []*File2_2         `json:"files"`
+	OtherLicenses []*OtherLicense2_2 `json:"hasExtractedLicensingInfos"`
+	Relationships []*Relationship2_2 `json:"relationships"`
+	Annotations   []*Annotation2_2   `json:"annotations"`
+	Snippets      []Snippet2_2       `json:"snippets"`
 
 	// DEPRECATED in version 2.0 of spec
 	Reviews []*Review2_2
diff --git a/spdx/file.go b/spdx/file.go
index a745dc3..01dbb36 100644
--- a/spdx/file.go
+++ b/spdx/file.go
@@ -4,68 +4,67 @@ package spdx
 
 // File2_1 is a File section of an SPDX Document for version 2.1 of the spec.
 type File2_1 struct {
-
 	// 4.1: File Name
 	// Cardinality: mandatory, one
-	FileName string
+	FileName string `json:"fileName"`
 
 	// 4.2: File SPDX Identifier: "SPDXRef-[idstring]"
 	// Cardinality: mandatory, one
-	FileSPDXIdentifier ElementID
+	FileSPDXIdentifier ElementID `json:"SPDXID"`
 
-	// 4.3: File Type
+	// 4.3: File Types
 	// Cardinality: optional, multiple
-	FileType []string
+	FileTypes []string `json:"fileTypes,omitempty"`
 
 	// 4.4: File Checksum: may have keys for SHA1, SHA256 and/or MD5
 	// Cardinality: mandatory, one SHA1, others may be optionally provided
-	FileChecksumSHA1   string
-	FileChecksumSHA256 string
-	FileChecksumMD5    string
+	Checksums []Checksum `json:"checksums"`
 
 	// 4.5: Concluded License: SPDX License Expression, "NONE" or "NOASSERTION"
 	// Cardinality: mandatory, one
-	LicenseConcluded string
+	LicenseConcluded string `json:"licenseConcluded"`
 
 	// 4.6: License Information in File: SPDX License Expression, "NONE" or "NOASSERTION"
 	// Cardinality: mandatory, one or many
-	LicenseInfoInFile []string
+	LicenseInfoInFiles []string `json:"licenseInfoInFiles"`
 
 	// 4.7: Comments on License
 	// Cardinality: optional, one
-	LicenseComments string
+	LicenseComments string `json:"licenseComments,omitempty"`
 
 	// 4.8: Copyright Text: copyright notice(s) text, "NONE" or "NOASSERTION"
 	// Cardinality: mandatory, one
-	FileCopyrightText string
+	FileCopyrightText string `json:"copyrightText"`
 
 	// DEPRECATED in version 2.1 of spec
 	// 4.9-4.11: Artifact of Project variables (defined below)
 	// Cardinality: optional, one or many
-	ArtifactOfProjects []*ArtifactOfProject2_1
+	ArtifactOfProjects []*ArtifactOfProject2_1 `json:"-"`
 
 	// 4.12: File Comment
 	// Cardinality: optional, one
-	FileComment string
+	FileComment string `json:"comment,omitempty"`
 
 	// 4.13: File Notice
 	// Cardinality: optional, one
-	FileNotice string
+	FileNotice string `json:"noticeText,omitempty"`
 
 	// 4.14: File Contributor
 	// Cardinality: optional, one or many
-	FileContributor []string
+	FileContributors []string `json:"fileContributors,omitempty"`
 
 	// DEPRECATED in version 2.0 of spec
 	// 4.15: File Dependencies
 	// Cardinality: optional, one or many
-	FileDependencies []string
+	FileDependencies []string `json:"-"`
 
 	// Snippets contained in this File
 	// Note that Snippets could be defined in a different Document! However,
-	// the only ones that _THIS_ document can contain are this ones that are
+	// the only ones that _THIS_ document can contain are the ones that are
 	// defined here -- so this should just be an ElementID.
-	Snippets map[ElementID]*Snippet2_1
+	Snippets map[ElementID]*Snippet2_1 `json:"-"`
+
+	Annotations []Annotation2_1 `json:"annotations"`
 }
 
 // ArtifactOfProject2_1 is a DEPRECATED collection of data regarding
@@ -90,70 +89,71 @@ type ArtifactOfProject2_1 struct {
 
 // File2_2 is a File section of an SPDX Document for version 2.2 of the spec.
 type File2_2 struct {
-
 	// 4.1: File Name
 	// Cardinality: mandatory, one
-	FileName string
+	FileName string `json:"fileName"`
 
 	// 4.2: File SPDX Identifier: "SPDXRef-[idstring]"
 	// Cardinality: mandatory, one
-	FileSPDXIdentifier ElementID
+	FileSPDXIdentifier ElementID `json:"SPDXID"`
 
-	// 4.3: File Type
+	// 4.3: File Types
 	// Cardinality: optional, multiple
-	FileType []string
+	FileTypes []string `json:"fileTypes,omitempty"`
 
 	// 4.4: File Checksum: may have keys for SHA1, SHA256 and/or MD5
 	// Cardinality: mandatory, one SHA1, others may be optionally provided
-	FileChecksums map[ChecksumAlgorithm]Checksum
+	Checksums []Checksum `json:"checksums"`
 
 	// 4.5: Concluded License: SPDX License Expression, "NONE" or "NOASSERTION"
 	// Cardinality: mandatory, one
-	LicenseConcluded string
+	LicenseConcluded string `json:"licenseConcluded"`
 
 	// 4.6: License Information in File: SPDX License Expression, "NONE" or "NOASSERTION"
 	// Cardinality: mandatory, one or many
-	LicenseInfoInFile []string
+	LicenseInfoInFiles []string `json:"licenseInfoInFiles"`
 
 	// 4.7: Comments on License
 	// Cardinality: optional, one
-	LicenseComments string
+	LicenseComments string `json:"licenseComments,omitempty"`
 
 	// 4.8: Copyright Text: copyright notice(s) text, "NONE" or "NOASSERTION"
 	// Cardinality: mandatory, one
-	FileCopyrightText string
+	FileCopyrightText string `json:"copyrightText"`
 
 	// DEPRECATED in version 2.1 of spec
 	// 4.9-4.11: Artifact of Project variables (defined below)
 	// Cardinality: optional, one or many
-	ArtifactOfProjects []*ArtifactOfProject2_2
+	ArtifactOfProjects []*ArtifactOfProject2_2 `json:"-"`
 
 	// 4.12: File Comment
 	// Cardinality: optional, one
-	FileComment string
+	FileComment string `json:"comment,omitempty"`
 
 	// 4.13: File Notice
 	// Cardinality: optional, one
-	FileNotice string
+	FileNotice string `json:"noticeText,omitempty"`
 
 	// 4.14: File Contributor
 	// Cardinality: optional, one or many
-	FileContributor []string
+	FileContributors []string `json:"fileContributors,omitempty"`
 
 	// 4.15: File Attribution Text
 	// Cardinality: optional, one or many
-	FileAttributionTexts []string
+	FileAttributionTexts []string `json:"attributionTexts,omitempty"`
 
 	// DEPRECATED in version 2.0 of spec
 	// 4.16: File Dependencies
 	// Cardinality: optional, one or many
-	FileDependencies []string
+	FileDependencies []string `json:"-"`
 
 	// Snippets contained in this File
 	// Note that Snippets could be defined in a different Document! However,
 	// the only ones that _THIS_ document can contain are this ones that are
 	// defined here -- so this should just be an ElementID.
-	Snippets map[ElementID]*Snippet2_2
+	Snippets map[ElementID]*Snippet2_2 `json:"-"`
+
+	Annotations []Annotation2_2 `json:"annotations,omitempty"`
 }
 
 // ArtifactOfProject2_2 is a DEPRECATED collection of data regarding
diff --git a/spdx/identifier.go b/spdx/identifier.go
index baf44c1..56f8ffc 100644
--- a/spdx/identifier.go
+++ b/spdx/identifier.go
@@ -2,6 +2,12 @@
 
 package spdx
 
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+)
+
 // ElementID represents the identifier string portion of an SPDX element
 // identifier. DocElementID should be used for any attributes which can
 // contain identifiers defined in a different SPDX document.
@@ -28,6 +34,62 @@ type DocElementID struct {
 	SpecialID     string
 }
 
+// UnmarshalJSON takes a SPDX Identifier string parses it into a DocElementID struct.
+// This function is also used when unmarshalling YAML
+func (d *DocElementID) UnmarshalJSON(data []byte) error {
+	// SPDX identifier will simply be a string
+	idStr := string(data)
+	idStr = strings.Trim(idStr, "\"")
+
+	// handle special cases
+	if idStr == "NONE" || idStr == "NOASSERTION" {
+		d.SpecialID = idStr
+		return nil
+	}
+
+	var idFields []string
+	// handle DocumentRef- if present
+	if strings.HasPrefix(idStr, "DocumentRef-") {
+		// strip out the "DocumentRef-" so we can get the value
+		idFields = strings.SplitN(idStr, "DocumentRef-", 2)
+		idStr = idFields[1]
+
+		// an SPDXRef can appear after a DocumentRef, separated by a colon
+		idFields = strings.SplitN(idStr, ":", 2)
+		d.DocumentRefID = idFields[0]
+
+		if len(idFields) == 2 {
+			idStr = idFields[1]
+		} else {
+			return nil
+		}
+	}
+
+	// handle SPDXRef-
+	idFields = strings.SplitN(idStr, "SPDXRef-", 2)
+	if len(idFields) != 2 {
+		return fmt.Errorf("failed to parse SPDX Identifier '%s'", idStr)
+	}
+
+	d.ElementRefID = ElementID(idFields[1])
+
+	return nil
+}
+
+// MarshalJSON converts the receiver into a slice of bytes representing a DocElementID in string form.
+// This function is also used when marshalling to YAML
+func (d DocElementID) MarshalJSON() ([]byte, error) {
+	if d.DocumentRefID != "" && d.ElementRefID != "" {
+		return json.Marshal(fmt.Sprintf("DocumentRef-%s:SPDXRef-%s", d.DocumentRefID, d.ElementRefID))
+	} else if d.ElementRefID != "" {
+		return json.Marshal(fmt.Sprintf("SPDXRef-%s", d.ElementRefID))
+	} else if d.SpecialID != "" {
+		return json.Marshal(d.SpecialID)
+	}
+
+	return []byte{}, fmt.Errorf("failed to marshal empty DocElementID")
+}
+
 // TODO: add equivalents for LicenseRef- identifiers
 
 // MakeDocElementID takes strings (without prefixes) for the DocumentRef-
diff --git a/spdx/other_license.go b/spdx/other_license.go
index a509c47..6e43676 100644
--- a/spdx/other_license.go
+++ b/spdx/other_license.go
@@ -5,57 +5,55 @@ package spdx
 // OtherLicense2_1 is an Other License Information section of an
 // SPDX Document for version 2.1 of the spec.
 type OtherLicense2_1 struct {
-
 	// 6.1: License Identifier: "LicenseRef-[idstring]"
 	// Cardinality: conditional (mandatory, one) if license is not
 	//              on SPDX License List
-	LicenseIdentifier string
+	LicenseIdentifier string `json:"licenseId"`
 
 	// 6.2: Extracted Text
 	// Cardinality: conditional (mandatory, one) if there is a
 	//              License Identifier assigned
-	ExtractedText string
+	ExtractedText string `json:"extractedText"`
 
 	// 6.3: License Name: single line of text or "NOASSERTION"
 	// Cardinality: conditional (mandatory, one) if license is not
 	//              on SPDX License List
-	LicenseName string
+	LicenseName string `json:"name,omitempty"`
 
 	// 6.4: License Cross Reference
 	// Cardinality: conditional (optional, one or many) if license
 	//              is not on SPDX License List
-	LicenseCrossReferences []string
+	LicenseCrossReferences []string `json:"seeAlsos,omitempty"`
 
 	// 6.5: License Comment
 	// Cardinality: optional, one
-	LicenseComment string
+	LicenseComment string `json:"comment,omitempty"`
 }
 
 // OtherLicense2_2 is an Other License Information section of an
 // SPDX Document for version 2.2 of the spec.
 type OtherLicense2_2 struct {
-
 	// 6.1: License Identifier: "LicenseRef-[idstring]"
 	// Cardinality: conditional (mandatory, one) if license is not
 	//              on SPDX License List
-	LicenseIdentifier string
+	LicenseIdentifier string `json:"licenseId"`
 
 	// 6.2: Extracted Text
 	// Cardinality: conditional (mandatory, one) if there is a
 	//              License Identifier assigned
-	ExtractedText string
+	ExtractedText string `json:"extractedText"`
 
 	// 6.3: License Name: single line of text or "NOASSERTION"
 	// Cardinality: conditional (mandatory, one) if license is not
 	//              on SPDX License List
-	LicenseName string
+	LicenseName string `json:"name,omitempty"`
 
 	// 6.4: License Cross Reference
 	// Cardinality: conditional (optional, one or many) if license
 	//              is not on SPDX License List
-	LicenseCrossReferences []string
+	LicenseCrossReferences []string `json:"seeAlsos,omitempty"`
 
 	// 6.5: License Comment
 	// Cardinality: optional, one
-	LicenseComment string
+	LicenseComment string `json:"comment,omitempty"`
 }
diff --git a/spdx/package.go b/spdx/package.go
index 9aeb8a2..e6c4522 100644
--- a/spdx/package.go
+++ b/spdx/package.go
@@ -2,140 +2,225 @@
 
 package spdx
 
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+)
+
+type Supplier struct {
+	// can be "NOASSERTION"
+	Supplier string
+	// SupplierType can be one of "Person", "Organization", or empty if Supplier is "NOASSERTION"
+	SupplierType string
+}
+
+// UnmarshalJSON takes a supplier in the typical one-line format and parses it into a Supplier struct.
+// This function is also used when unmarshalling YAML
+func (s *Supplier) UnmarshalJSON(data []byte) error {
+	// the value is just a string presented as a slice of bytes
+	supplierStr := string(data)
+	supplierStr = strings.Trim(supplierStr, "\"")
+
+	if supplierStr == "NOASSERTION" {
+		s.Supplier = supplierStr
+		return nil
+	}
+
+	supplierFields := strings.SplitN(supplierStr, ": ", 2)
+
+	if len(supplierFields) != 2 {
+		return fmt.Errorf("failed to parse Supplier '%s'", supplierStr)
+	}
+
+	s.SupplierType = supplierFields[0]
+	s.Supplier = supplierFields[1]
+
+	return nil
+}
+
+// MarshalJSON converts the receiver into a slice of bytes representing a Supplier in string form.
+// This function is also used when marshalling to YAML
+func (s Supplier) MarshalJSON() ([]byte, error) {
+	if s.Supplier == "NOASSERTION" {
+		return json.Marshal(s.Supplier)
+	} else if s.SupplierType != "" && s.Supplier != "" {
+		return json.Marshal(fmt.Sprintf("%s: %s", s.SupplierType, s.Supplier))
+	}
+
+	return []byte{}, fmt.Errorf("failed to marshal invalid Supplier: %+v", s)
+}
+
+type Originator struct {
+	// can be "NOASSERTION"
+	Originator string
+	// OriginatorType can be one of "Person", "Organization", or empty if Originator is "NOASSERTION"
+	OriginatorType string
+}
+
+// UnmarshalJSON takes an originator in the typical one-line format and parses it into an Originator struct.
+// This function is also used when unmarshalling YAML
+func (o *Originator) UnmarshalJSON(data []byte) error {
+	// the value is just a string presented as a slice of bytes
+	originatorStr := string(data)
+	originatorStr = strings.Trim(originatorStr, "\"")
+
+	if originatorStr == "NOASSERTION" {
+		o.Originator = originatorStr
+		return nil
+	}
+
+	originatorFields := strings.SplitN(originatorStr, ": ", 2)
+
+	if len(originatorFields) != 2 {
+		return fmt.Errorf("failed to parse Originator '%s'", originatorStr)
+	}
+
+	o.OriginatorType = originatorFields[0]
+	o.Originator = originatorFields[1]
+
+	return nil
+}
+
+// MarshalJSON converts the receiver into a slice of bytes representing an Originator in string form.
+// This function is also used when marshalling to YAML
+func (o Originator) MarshalJSON() ([]byte, error) {
+	if o.Originator == "NOASSERTION" {
+		return json.Marshal(o.Originator)
+	} else if o.Originator != "" {
+		return json.Marshal(fmt.Sprintf("%s: %s", o.OriginatorType, o.Originator))
+	}
+
+	return []byte{}, nil
+}
+
+type PackageVerificationCode struct {
+	// Cardinality: mandatory, one if filesAnalyzed is true / omitted;
+	//              zero (must be omitted) if filesAnalyzed is false
+	Value string `json:"packageVerificationCodeValue"`
+	// Spec also allows specifying files to exclude from the
+	// verification code algorithm; intended to enable exclusion of
+	// the SPDX document file itself.
+	ExcludedFiles []string `json:"packageVerificationCodeExcludedFiles"`
+}
+
 // Package2_1 is a Package section of an SPDX Document for version 2.1 of the spec.
 type Package2_1 struct {
-
 	// 3.1: Package Name
 	// Cardinality: mandatory, one
-	PackageName string
+	PackageName string `json:"name"`
 
 	// 3.2: Package SPDX Identifier: "SPDXRef-[idstring]"
 	// Cardinality: mandatory, one
-	PackageSPDXIdentifier ElementID
+	PackageSPDXIdentifier ElementID `json:"SPDXID"`
 
 	// 3.3: Package Version
 	// Cardinality: optional, one
-	PackageVersion string
+	PackageVersion string `json:"versionInfo,omitempty"`
 
 	// 3.4: Package File Name
 	// Cardinality: optional, one
-	PackageFileName string
+	PackageFileName string `json:"packageFileName,omitempty"`
 
 	// 3.5: Package Supplier: may have single result for either Person or Organization,
 	//                        or NOASSERTION
 	// Cardinality: optional, one
-	PackageSupplierPerson       string
-	PackageSupplierOrganization string
-	PackageSupplierNOASSERTION  bool
+	PackageSupplier *Supplier `json:"supplier,omitempty"`
 
 	// 3.6: Package Originator: may have single result for either Person or Organization,
 	//                          or NOASSERTION
 	// Cardinality: optional, one
-	PackageOriginatorPerson       string
-	PackageOriginatorOrganization string
-	PackageOriginatorNOASSERTION  bool
+	PackageOriginator *Originator `json:"originator,omitempty"`
 
 	// 3.7: Package Download Location
 	// Cardinality: mandatory, one
-	PackageDownloadLocation string
+	PackageDownloadLocation string `json:"downloadLocation"`
 
 	// 3.8: FilesAnalyzed
 	// Cardinality: optional, one; default value is "true" if omitted
-	FilesAnalyzed bool
+	FilesAnalyzed bool `json:"filesAnalyzed,omitempty"`
 	// NOT PART OF SPEC: did FilesAnalyzed tag appear?
-	IsFilesAnalyzedTagPresent bool
+	IsFilesAnalyzedTagPresent bool `json:"-"`
 
 	// 3.9: Package Verification Code
-	// Cardinality: mandatory, one if filesAnalyzed is true / omitted;
-	//              zero (must be omitted) if filesAnalyzed is false
-	PackageVerificationCode string
-	// Spec also allows specifying a single file to exclude from the
-	// verification code algorithm; intended to enable exclusion of
-	// the SPDX document file itself.
-	PackageVerificationCodeExcludedFile string
+	PackageVerificationCode PackageVerificationCode `json:"packageVerificationCode"`
 
 	// 3.10: Package Checksum: may have keys for SHA1, SHA256 and/or MD5
 	// Cardinality: optional, one or many
-	PackageChecksumSHA1   string
-	PackageChecksumSHA256 string
-	PackageChecksumMD5    string
+	PackageChecksums []Checksum `json:"checksums,omitempty"`
 
 	// 3.11: Package Home Page
 	// Cardinality: optional, one
-	PackageHomePage string
+	PackageHomePage string `json:"homepage,omitempty"`
 
 	// 3.12: Source Information
 	// Cardinality: optional, one
-	PackageSourceInfo string
+	PackageSourceInfo string `json:"sourceInfo,omitempty"`
 
 	// 3.13: Concluded License: SPDX License Expression, "NONE" or "NOASSERTION"
 	// Cardinality: mandatory, one
-	PackageLicenseConcluded string
+	PackageLicenseConcluded string `json:"licenseConcluded"`
 
 	// 3.14: All Licenses Info from Files: SPDX License Expression, "NONE" or "NOASSERTION"
 	// Cardinality: mandatory, one or many if filesAnalyzed is true / omitted;
 	//              zero (must be omitted) if filesAnalyzed is false
-	PackageLicenseInfoFromFiles []string
+	PackageLicenseInfoFromFiles []string `json:"licenseInfoFromFiles"`
 
 	// 3.15: Declared License: SPDX License Expression, "NONE" or "NOASSERTION"
 	// Cardinality: mandatory, one
-	PackageLicenseDeclared string
+	PackageLicenseDeclared string `json:"licenseDeclared"`
 
 	// 3.16: Comments on License
 	// Cardinality: optional, one
-	PackageLicenseComments string
+	PackageLicenseComments string `json:"licenseComments,omitempty"`
 
 	// 3.17: Copyright Text: copyright notice(s) text, "NONE" or "NOASSERTION"
 	// Cardinality: mandatory, one
-	PackageCopyrightText string
+	PackageCopyrightText string `json:"copyrightText"`
 
 	// 3.18: Package Summary Description
 	// Cardinality: optional, one
-	PackageSummary string
+	PackageSummary string `json:"summary,omitempty"`
 
 	// 3.19: Package Detailed Description
 	// Cardinality: optional, one
-	PackageDescription string
+	PackageDescription string `json:"description,omitempty"`
 
 	// 3.20: Package Comment
 	// Cardinality: optional, one
-	PackageComment string
+	PackageComment string `json:"comment,omitempty"`
 
 	// 3.21: Package External Reference
 	// Cardinality: optional, one or many
-	PackageExternalReferences []*PackageExternalReference2_1
-
-	// 3.22: Package External Reference Comment
-	// Cardinality: conditional (optional, one) for each External Reference
-	// contained within PackageExternalReference2_1 struct, if present
+	PackageExternalReferences []*PackageExternalReference2_1 `json:"externalRefs,omitempty"`
 
 	// Files contained in this Package
-	Files map[ElementID]*File2_1
+	Files []*File2_1
+
+	Annotations []Annotation2_1 `json:"annotations,omitempty"`
 }
 
 // PackageExternalReference2_1 is an External Reference to additional info
 // about a Package, as defined in section 3.21 in version 2.1 of the spec.
 type PackageExternalReference2_1 struct {
-
 	// category is "SECURITY", "PACKAGE-MANAGER" or "OTHER"
-	Category string
+	Category string `json:"referenceCategory"`
 
 	// type is an [idstring] as defined in Appendix VI;
 	// called RefType here due to "type" being a Golang keyword
-	RefType string
+	RefType string `json:"referenceType"`
 
 	// locator is a unique string to access the package-specific
 	// info, metadata or content within the target location
-	Locator string
+	Locator string `json:"referenceLocator"`
 
 	// 3.22: Package External Reference Comment
 	// Cardinality: conditional (optional, one) for each External Reference
-	ExternalRefComment string
+	ExternalRefComment string `json:"comment"`
 }
 
 // Package2_2 is a Package section of an SPDX Document for version 2.2 of the spec.
 type Package2_2 struct {
-
 	// NOT PART OF SPEC
 	// flag: does this "package" contain files that were in fact "unpackaged",
 	// e.g. included directly in the Document without being in a Package?
@@ -143,101 +228,91 @@ type Package2_2 struct {
 
 	// 3.1: Package Name
 	// Cardinality: mandatory, one
-	PackageName string
+	PackageName string `json:"name"`
 
 	// 3.2: Package SPDX Identifier: "SPDXRef-[idstring]"
 	// Cardinality: mandatory, one
-	PackageSPDXIdentifier ElementID
+	PackageSPDXIdentifier ElementID `json:"SPDXID"`
 
 	// 3.3: Package Version
 	// Cardinality: optional, one
-	PackageVersion string
+	PackageVersion string `json:"versionInfo,omitempty"`
 
 	// 3.4: Package File Name
 	// Cardinality: optional, one
-	PackageFileName string
+	PackageFileName string `json:"packageFileName,omitempty"`
 
 	// 3.5: Package Supplier: may have single result for either Person or Organization,
 	//                        or NOASSERTION
 	// Cardinality: optional, one
-	PackageSupplierPerson       string
-	PackageSupplierOrganization string
-	PackageSupplierNOASSERTION  bool
+	PackageSupplier *Supplier `json:"supplier,omitempty"`
 
 	// 3.6: Package Originator: may have single result for either Person or Organization,
 	//                          or NOASSERTION
 	// Cardinality: optional, one
-	PackageOriginatorPerson       string
-	PackageOriginatorOrganization string
-	PackageOriginatorNOASSERTION  bool
+	PackageOriginator *Originator `json:"originator,omitempty"`
 
 	// 3.7: Package Download Location
 	// Cardinality: mandatory, one
-	PackageDownloadLocation string
+	PackageDownloadLocation string `json:"downloadLocation"`
 
 	// 3.8: FilesAnalyzed
 	// Cardinality: optional, one; default value is "true" if omitted
-	FilesAnalyzed bool
+	FilesAnalyzed bool `json:"filesAnalyzed,omitempty"`
 	// NOT PART OF SPEC: did FilesAnalyzed tag appear?
 	IsFilesAnalyzedTagPresent bool
 
 	// 3.9: Package Verification Code
-	// Cardinality: mandatory, one if filesAnalyzed is true / omitted;
-	//              zero (must be omitted) if filesAnalyzed is false
-	PackageVerificationCode string
-	// Spec also allows specifying a single file to exclude from the
-	// verification code algorithm; intended to enable exclusion of
-	// the SPDX document file itself.
-	PackageVerificationCodeExcludedFile string
+	PackageVerificationCode PackageVerificationCode `json:"packageVerificationCode"`
 
 	// 3.10: Package Checksum: may have keys for SHA1, SHA256 and/or MD5
 	// Cardinality: optional, one or many
-	PackageChecksums map[ChecksumAlgorithm]Checksum
+	PackageChecksums []Checksum `json:"checksums"`
 
 	// 3.11: Package Home Page
 	// Cardinality: optional, one
-	PackageHomePage string
+	PackageHomePage string `json:"homepage,omitempty"`
 
 	// 3.12: Source Information
 	// Cardinality: optional, one
-	PackageSourceInfo string
+	PackageSourceInfo string `json:"sourceInfo,omitempty"`
 
 	// 3.13: Concluded License: SPDX License Expression, "NONE" or "NOASSERTION"
 	// Cardinality: mandatory, one
-	PackageLicenseConcluded string
+	PackageLicenseConcluded string `json:"licenseConcluded"`
 
 	// 3.14: All Licenses Info from Files: SPDX License Expression, "NONE" or "NOASSERTION"
 	// Cardinality: mandatory, one or many if filesAnalyzed is true / omitted;
 	//              zero (must be omitted) if filesAnalyzed is false
-	PackageLicenseInfoFromFiles []string
+	PackageLicenseInfoFromFiles []string `json:"licenseInfoFromFiles"`
 
 	// 3.15: Declared License: SPDX License Expression, "NONE" or "NOASSERTION"
 	// Cardinality: mandatory, one
-	PackageLicenseDeclared string
+	PackageLicenseDeclared string `json:"licenseDeclared"`
 
 	// 3.16: Comments on License
 	// Cardinality: optional, one
-	PackageLicenseComments string
+	PackageLicenseComments string `json:"licenseComments,omitempty"`
 
 	// 3.17: Copyright Text: copyright notice(s) text, "NONE" or "NOASSERTION"
 	// Cardinality: mandatory, one
-	PackageCopyrightText string
+	PackageCopyrightText string `json:"copyrightText"`
 
 	// 3.18: Package Summary Description
 	// Cardinality: optional, one
-	PackageSummary string
+	PackageSummary string `json:"summary,omitempty"`
 
 	// 3.19: Package Detailed Description
 	// Cardinality: optional, one
-	PackageDescription string
+	PackageDescription string `json:"description,omitempty"`
 
 	// 3.20: Package Comment
 	// Cardinality: optional, one
-	PackageComment string
+	PackageComment string `json:"comment,omitempty"`
 
 	// 3.21: Package External Reference
 	// Cardinality: optional, one or many
-	PackageExternalReferences []*PackageExternalReference2_2
+	PackageExternalReferences []*PackageExternalReference2_2 `json:"externalRefs,omitempty"`
 
 	// 3.22: Package External Reference Comment
 	// Cardinality: conditional (optional, one) for each External Reference
@@ -245,28 +320,29 @@ type Package2_2 struct {
 
 	// 3.23: Package Attribution Text
 	// Cardinality: optional, one or many
-	PackageAttributionTexts []string
+	PackageAttributionTexts []string `json:"attributionTexts,omitempty"`
 
 	// Files contained in this Package
-	Files map[ElementID]*File2_2
+	Files []*File2_2
+
+	Annotations []Annotation2_2 `json:"annotations"`
 }
 
 // PackageExternalReference2_2 is an External Reference to additional info
 // about a Package, as defined in section 3.21 in version 2.2 of the spec.
 type PackageExternalReference2_2 struct {
-
-	// category is "SECURITY", "PACKAGE-MANAGER", "PERSISTENT-ID" or "OTHER"
-	Category string
+	// category is "SECURITY", "PACKAGE-MANAGER" or "OTHER"
+	Category string `json:"referenceCategory"`
 
 	// type is an [idstring] as defined in Appendix VI;
 	// called RefType here due to "type" being a Golang keyword
-	RefType string
+	RefType string `json:"referenceType"`
 
 	// locator is a unique string to access the package-specific
 	// info, metadata or content within the target location
-	Locator string
+	Locator string `json:"referenceLocator"`
 
 	// 3.22: Package External Reference Comment
 	// Cardinality: conditional (optional, one) for each External Reference
-	ExternalRefComment string
+	ExternalRefComment string `json:"comment"`
 }
diff --git a/spdx/relationship.go b/spdx/relationship.go
index 9e06838..9127727 100644
--- a/spdx/relationship.go
+++ b/spdx/relationship.go
@@ -11,13 +11,13 @@ type Relationship2_1 struct {
 	//              one mandatory for SPDX Document with multiple packages
 	// RefA and RefB are first and second item
 	// Relationship is type from 7.1.1
-	RefA         DocElementID
-	RefB         DocElementID
-	Relationship string
+	RefA         DocElementID `json:"spdxElementId"`
+	RefB         DocElementID `json:"relatedSpdxElement"`
+	Relationship string       `json:"relationshipType"`
 
 	// 7.2: Relationship Comment
 	// Cardinality: optional, one
-	RelationshipComment string
+	RelationshipComment string `json:"comment,omitempty"`
 }
 
 // Relationship2_2 is a Relationship section of an SPDX Document for
@@ -29,11 +29,11 @@ type Relationship2_2 struct {
 	//              one mandatory for SPDX Document with multiple packages
 	// RefA and RefB are first and second item
 	// Relationship is type from 7.1.1
-	RefA         DocElementID
-	RefB         DocElementID
-	Relationship string
+	RefA         DocElementID `json:"spdxElementId"`
+	RefB         DocElementID `json:"relatedSpdxElement"`
+	Relationship string       `json:"relationshipType"`
 
 	// 7.2: Relationship Comment
 	// Cardinality: optional, one
-	RelationshipComment string
+	RelationshipComment string `json:"comment,omitempty"`
 }
diff --git a/spdx/snippet.go b/spdx/snippet.go
index 5fe37ca..6bffb8c 100644
--- a/spdx/snippet.go
+++ b/spdx/snippet.go
@@ -2,50 +2,60 @@
 
 package spdx
 
+type SnippetRangePointer struct {
+	// 5.3: Snippet Byte Range: [start byte]:[end byte]
+	// Cardinality: mandatory, one
+	Offset int `json:"offset,omitempty"`
+
+	// 5.4: Snippet Line Range: [start line]:[end line]
+	// Cardinality: optional, one
+	LineNumber int `json:"lineNumber,omitempty"`
+
+	FileSPDXIdentifier ElementID `json:"reference"`
+}
+
+type SnippetRange struct {
+	StartPointer SnippetRangePointer `json:"startPointer"`
+	EndPointer   SnippetRangePointer `json:"endPointer"`
+}
+
 // Snippet2_1 is a Snippet section of an SPDX Document for version 2.1 of the spec.
 type Snippet2_1 struct {
 
 	// 5.1: Snippet SPDX Identifier: "SPDXRef-[idstring]"
 	// Cardinality: mandatory, one
-	SnippetSPDXIdentifier ElementID
+	SnippetSPDXIdentifier ElementID `json:"SPDXID"`
 
 	// 5.2: Snippet from File SPDX Identifier
 	// Cardinality: mandatory, one
-	SnippetFromFileSPDXIdentifier DocElementID
+	SnippetFromFileSPDXIdentifier ElementID `json:"snippetFromFile"`
 
-	// 5.3: Snippet Byte Range: [start byte]:[end byte]
-	// Cardinality: mandatory, one
-	SnippetByteRangeStart int
-	SnippetByteRangeEnd   int
-
-	// 5.4: Snippet Line Range: [start line]:[end line]
-	// Cardinality: optional, one
-	SnippetLineRangeStart int
-	SnippetLineRangeEnd   int
+	// Ranges denotes the start/end byte offsets or line numbers that the snippet is relevant to
+	Ranges []SnippetRange `json:"ranges"`
 
 	// 5.5: Snippet Concluded License: SPDX License Expression, "NONE" or "NOASSERTION"
 	// Cardinality: mandatory, one
-	SnippetLicenseConcluded string
+	SnippetLicenseConcluded string `json:"licenseConcluded"`
 
 	// 5.6: License Information in Snippet: SPDX License Expression, "NONE" or "NOASSERTION"
 	// Cardinality: optional, one or many
-	LicenseInfoInSnippet []string
+	LicenseInfoInSnippet []string `json:"licenseInfoInSnippets,omitempty"`
 
 	// 5.7: Snippet Comments on License
 	// Cardinality: optional, one
-	SnippetLicenseComments string
+	SnippetLicenseComments string `json:"licenseComments,omitempty"`
 
 	// 5.8: Snippet Copyright Text: copyright notice(s) text, "NONE" or "NOASSERTION"
 	// Cardinality: mandatory, one
-	SnippetCopyrightText string
+	SnippetCopyrightText string `json:"copyrightText"`
 
 	// 5.9: Snippet Comment
 	// Cardinality: optional, one
-	SnippetComment string
+	SnippetComment string `json:"comment,omitempty"`
 
 	// 5.10: Snippet Name
 	// Cardinality: optional, one
-	SnippetName string
+	SnippetName string `json:"name,omitempty"`
 }
 
 // Snippet2_2 is a Snippet section of an SPDX Document for version 2.2 of the spec.
@@ -53,47 +63,40 @@ type Snippet2_2 struct {
 
 	// 5.1: Snippet SPDX Identifier: "SPDXRef-[idstring]"
 	// Cardinality: mandatory, one
-	SnippetSPDXIdentifier ElementID
+	SnippetSPDXIdentifier ElementID `json:"SPDXID"`
 
 	// 5.2: Snippet from File SPDX Identifier
 	// Cardinality: mandatory, one
-	SnippetFromFileSPDXIdentifier DocElementID
+	SnippetFromFileSPDXIdentifier ElementID `json:"snippetFromFile"`
 
-	// 5.3: Snippet Byte Range: [start byte]:[end byte]
-	// Cardinality: mandatory, one
-	SnippetByteRangeStart int
-	SnippetByteRangeEnd   int
-
-	// 5.4: Snippet Line Range: [start line]:[end line]
-	// Cardinality: optional, one
-	SnippetLineRangeStart int
-	SnippetLineRangeEnd   int
+	// Ranges denotes the start/end byte offsets or line numbers that the snippet is relevant to
+	Ranges []SnippetRange `json:"ranges"`
 
 	// 5.5: Snippet Concluded License: SPDX License Expression, "NONE" or "NOASSERTION"
 	// Cardinality: mandatory, one
-	SnippetLicenseConcluded string
+	SnippetLicenseConcluded string `json:"licenseConcluded"`
 
 	// 5.6: License Information in Snippet: SPDX License Expression, "NONE" or "NOASSERTION"
 	// Cardinality: optional, one or many
-	LicenseInfoInSnippet []string
+	LicenseInfoInSnippet []string `json:"licenseInfoInSnippets,omitempty"`
 
 	// 5.7: Snippet Comments on License
 	// Cardinality: optional, one
-	SnippetLicenseComments string
+	SnippetLicenseComments string `json:"licenseComments,omitempty"`
 
 	// 5.8: Snippet Copyright Text: copyright notice(s) text, "NONE" or "NOASSERTION"
 	// Cardinality: mandatory, one
-	SnippetCopyrightText string
+	SnippetCopyrightText string `json:"copyrightText"`
 
 	// 5.9: Snippet Comment
 	// Cardinality: optional, one
-	SnippetComment string
+	SnippetComment string `json:"comment,omitempty"`
 
 	// 5.10: Snippet Name
 	// Cardinality: optional, one
-	SnippetName string
+	SnippetName string `json:"name,omitempty"`
 
 	// 5.11: Snippet Attribution Text
 	// Cardinality: optional, one or many
-	SnippetAttributionTexts []string
+	SnippetAttributionTexts []string `json:"-"`
 }