|  | 
|  | 1 | +/** | 
|  | 2 | + * OCI Annotations support for WebAssembly components | 
|  | 3 | + * | 
|  | 4 | + * This module implements the WebAssembly tool-conventions for OCI annotations | 
|  | 5 | + * as defined in: https://github.com/WebAssembly/tool-conventions/pull/248 | 
|  | 6 | + * | 
|  | 7 | + * The following custom sections are supported: | 
|  | 8 | + * - version: Version of the packaged software | 
|  | 9 | + * - description: Human-readable description of the binary | 
|  | 10 | + * - authors: Contact details of the authors | 
|  | 11 | + * - licenses: SPDX license expression | 
|  | 12 | + * - homepage: URL to find more information about the package | 
|  | 13 | + * - source: URL to get source code for building the package | 
|  | 14 | + * - revision: Hash of the commit used to build the package | 
|  | 15 | + */ | 
|  | 16 | + | 
|  | 17 | +/** | 
|  | 18 | + * Encode a number as LEB128 unsigned integer | 
|  | 19 | + * @param {number} value | 
|  | 20 | + * @returns {Uint8Array} | 
|  | 21 | + */ | 
|  | 22 | +function encodeLEB128(value) { | 
|  | 23 | +  const bytes = []; | 
|  | 24 | +  do { | 
|  | 25 | +    let byte = value & 0x7f; | 
|  | 26 | +    value >>= 7; | 
|  | 27 | +    if (value !== 0) { | 
|  | 28 | +      byte |= 0x80; | 
|  | 29 | +    } | 
|  | 30 | +    bytes.push(byte); | 
|  | 31 | +  } while (value !== 0); | 
|  | 32 | +  return new Uint8Array(bytes); | 
|  | 33 | +} | 
|  | 34 | + | 
|  | 35 | +/** | 
|  | 36 | + * Encode a custom section with the given name and data | 
|  | 37 | + * @param {string} name - Section name | 
|  | 38 | + * @param {string} data - Section data (UTF-8 string) | 
|  | 39 | + * @returns {Uint8Array} | 
|  | 40 | + */ | 
|  | 41 | +function encodeCustomSection(name, data) { | 
|  | 42 | +  const nameBytes = new TextEncoder().encode(name); | 
|  | 43 | +  const dataBytes = new TextEncoder().encode(data); | 
|  | 44 | + | 
|  | 45 | +  const nameLengthBytes = encodeLEB128(nameBytes.length); | 
|  | 46 | +  const payloadSize = nameLengthBytes.length + nameBytes.length + dataBytes.length; | 
|  | 47 | +  const sectionSizeBytes = encodeLEB128(payloadSize); | 
|  | 48 | + | 
|  | 49 | +  // Custom section ID is 0 | 
|  | 50 | +  const sectionId = new Uint8Array([0]); | 
|  | 51 | + | 
|  | 52 | +  // Concatenate all parts | 
|  | 53 | +  const section = new Uint8Array( | 
|  | 54 | +    sectionId.length + | 
|  | 55 | +    sectionSizeBytes.length + | 
|  | 56 | +    nameLengthBytes.length + | 
|  | 57 | +    nameBytes.length + | 
|  | 58 | +    dataBytes.length | 
|  | 59 | +  ); | 
|  | 60 | + | 
|  | 61 | +  let offset = 0; | 
|  | 62 | +  section.set(sectionId, offset); | 
|  | 63 | +  offset += sectionId.length; | 
|  | 64 | +  section.set(sectionSizeBytes, offset); | 
|  | 65 | +  offset += sectionSizeBytes.length; | 
|  | 66 | +  section.set(nameLengthBytes, offset); | 
|  | 67 | +  offset += nameLengthBytes.length; | 
|  | 68 | +  section.set(nameBytes, offset); | 
|  | 69 | +  offset += nameBytes.length; | 
|  | 70 | +  section.set(dataBytes, offset); | 
|  | 71 | + | 
|  | 72 | +  return section; | 
|  | 73 | +} | 
|  | 74 | + | 
|  | 75 | +/** | 
|  | 76 | + * Add OCI annotation custom sections to a WebAssembly component | 
|  | 77 | + * @param {Uint8Array} component - The WebAssembly component binary | 
|  | 78 | + * @param {Object} annotations - OCI annotations to add | 
|  | 79 | + * @param {string} [annotations.version] - Package version | 
|  | 80 | + * @param {string} [annotations.description] - Package description | 
|  | 81 | + * @param {string} [annotations.authors] - Package authors (freeform contact details) | 
|  | 82 | + * @param {string} [annotations.licenses] - SPDX license expression | 
|  | 83 | + * @param {string} [annotations.homepage] - Package homepage URL | 
|  | 84 | + * @param {string} [annotations.source] - Source repository URL | 
|  | 85 | + * @param {string} [annotations.revision] - Source revision/commit hash | 
|  | 86 | + * @returns {Uint8Array} - Component with OCI annotations added | 
|  | 87 | + */ | 
|  | 88 | +export function addOCIAnnotations(component, annotations) { | 
|  | 89 | +  if (!annotations || Object.keys(annotations).length === 0) { | 
|  | 90 | +    return component; | 
|  | 91 | +  } | 
|  | 92 | + | 
|  | 93 | +  const sections = []; | 
|  | 94 | + | 
|  | 95 | +  // Add each annotation as a custom section | 
|  | 96 | +  // Order matters: add in a consistent order for reproducibility | 
|  | 97 | +  const fields = ['version', 'description', 'authors', 'licenses', 'homepage', 'source', 'revision']; | 
|  | 98 | + | 
|  | 99 | +  for (const field of fields) { | 
|  | 100 | +    if (annotations[field]) { | 
|  | 101 | +      sections.push(encodeCustomSection(field, annotations[field])); | 
|  | 102 | +    } | 
|  | 103 | +  } | 
|  | 104 | + | 
|  | 105 | +  if (sections.length === 0) { | 
|  | 106 | +    return component; | 
|  | 107 | +  } | 
|  | 108 | + | 
|  | 109 | +  // Calculate total size needed | 
|  | 110 | +  let totalSize = component.length; | 
|  | 111 | +  for (const section of sections) { | 
|  | 112 | +    totalSize += section.length; | 
|  | 113 | +  } | 
|  | 114 | + | 
|  | 115 | +  // The WebAssembly module/component starts with a magic number and version | 
|  | 116 | +  // Magic: 0x00 0x61 0x73 0x6d (for modules) | 
|  | 117 | +  // Component magic: 0x00 0x61 0x73 0x6d (same magic, different layer encoding) | 
|  | 118 | +  // Version: 4 bytes | 
|  | 119 | +  // We want to insert custom sections after the header (8 bytes) | 
|  | 120 | + | 
|  | 121 | +  const WASM_HEADER_SIZE = 8; | 
|  | 122 | +  const result = new Uint8Array(totalSize); | 
|  | 123 | + | 
|  | 124 | +  // Copy header | 
|  | 125 | +  result.set(component.subarray(0, WASM_HEADER_SIZE), 0); | 
|  | 126 | + | 
|  | 127 | +  let offset = WASM_HEADER_SIZE; | 
|  | 128 | + | 
|  | 129 | +  // Add custom sections | 
|  | 130 | +  for (const section of sections) { | 
|  | 131 | +    result.set(section, offset); | 
|  | 132 | +    offset += section.length; | 
|  | 133 | +  } | 
|  | 134 | + | 
|  | 135 | +  // Copy rest of component | 
|  | 136 | +  result.set(component.subarray(WASM_HEADER_SIZE), offset); | 
|  | 137 | + | 
|  | 138 | +  return result; | 
|  | 139 | +} | 
|  | 140 | + | 
|  | 141 | +/** | 
|  | 142 | + * Extract OCI annotations from package.json metadata | 
|  | 143 | + * @param {Object} packageJson - Parsed package.json content | 
|  | 144 | + * @returns {Object} OCI annotations | 
|  | 145 | + */ | 
|  | 146 | +export function extractAnnotationsFromPackageJson(packageJson) { | 
|  | 147 | +  const annotations = {}; | 
|  | 148 | + | 
|  | 149 | +  if (packageJson.version) { | 
|  | 150 | +    annotations.version = packageJson.version; | 
|  | 151 | +  } | 
|  | 152 | + | 
|  | 153 | +  if (packageJson.description) { | 
|  | 154 | +    annotations.description = packageJson.description; | 
|  | 155 | +  } | 
|  | 156 | + | 
|  | 157 | +  // Authors can be a string or an array of objects/strings | 
|  | 158 | +  if (packageJson.author) { | 
|  | 159 | +    if (typeof packageJson.author === 'string') { | 
|  | 160 | +      annotations.authors = packageJson.author; | 
|  | 161 | +    } else if (packageJson.author.name) { | 
|  | 162 | +      const author = packageJson.author; | 
|  | 163 | +      let authorStr = author.name; | 
|  | 164 | +      if (author.email) authorStr += ` <${author.email}>`; | 
|  | 165 | +      annotations.authors = authorStr; | 
|  | 166 | +    } | 
|  | 167 | +  } else if (packageJson.authors && Array.isArray(packageJson.authors)) { | 
|  | 168 | +    const authorStrs = packageJson.authors.map(a => { | 
|  | 169 | +      if (typeof a === 'string') return a; | 
|  | 170 | +      let str = a.name || ''; | 
|  | 171 | +      if (a.email) str += ` <${a.email}>`; | 
|  | 172 | +      return str; | 
|  | 173 | +    }).filter(s => s); | 
|  | 174 | +    if (authorStrs.length > 0) { | 
|  | 175 | +      annotations.authors = authorStrs.join(', '); | 
|  | 176 | +    } | 
|  | 177 | +  } | 
|  | 178 | + | 
|  | 179 | +  if (packageJson.license) { | 
|  | 180 | +    annotations.licenses = packageJson.license; | 
|  | 181 | +  } | 
|  | 182 | + | 
|  | 183 | +  if (packageJson.homepage) { | 
|  | 184 | +    annotations.homepage = packageJson.homepage; | 
|  | 185 | +  } | 
|  | 186 | + | 
|  | 187 | +  // Extract source URL from repository field | 
|  | 188 | +  if (packageJson.repository) { | 
|  | 189 | +    if (typeof packageJson.repository === 'string') { | 
|  | 190 | +      annotations.source = packageJson.repository; | 
|  | 191 | +    } else if (packageJson.repository.url) { | 
|  | 192 | +      annotations.source = packageJson.repository.url; | 
|  | 193 | +    } | 
|  | 194 | +  } | 
|  | 195 | + | 
|  | 196 | +  return annotations; | 
|  | 197 | +} | 
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