feat(remediation): add remediation extractor with provider priority resolution

src/remediation.js

@@ -0,0 +1,342 @@
+import { PackageURL } from 'packageurl-js'
+
+/**
+ * Extracts actionable remediation instructions from a DA AnalysisReport response.
+ *
+ * Walks the provider/source/dependency/issue tree, collects fixedIn and trustedContent
+ * remediation data, applies provider priority resolution, and for the same dependency
+ * affected by multiple CVEs selects the highest fixedIn version from the highest-priority
+ * provider. Dependencies with no remediation data are skipped.
+ *
+ * @param {object} analysisReport - raw DA AnalysisReport JSON response
+ * @param {object} [options] - extraction options
+ * @param {string[]} [options.providerPriority] - provider names in descending priority order.
+ *   The first entry has the highest priority. Providers not listed share the lowest priority.
+ *   When omitted or empty, all providers are treated equally and the highest fix version wins.
+ * @returns {Array<{purl: string, groupId: string, artifactId: string, currentVersion: string, fixedInVersion: string, fixedInPurl: string, provider: string, source: string, advisories: Array<{id: string, url: string}>, severity: string, cves: string[]}>}
+ */
+export function extractRemediations(analysisReport, options = {}) {
+	if (!analysisReport || !analysisReport.providers) {
+		return []
+	}
+
+	const priorityMap = buildPriorityMap(options.providerPriority)
+	const remediationsByDep = new Map()
+	const rankByDep = new Map()
+
+	for (const [providerName, providerReport] of Object.entries(analysisReport.providers)) {
+		const providerRank = priorityMap.get(providerName) ?? 0
+		extractFromSources(providerReport, providerName, providerRank, remediationsByDep, rankByDep)
+		extractFromRecommendations(providerReport, providerName, providerRank, remediationsByDep, rankByDep)
+	}
+
+	return Array.from(remediationsByDep.values())
+		.sort((a, b) => a.purl.localeCompare(b.purl))
+}
+
+/**
+ * Builds a priority lookup map from a provider priority array.
+ * First entry gets the highest numeric priority.
+ * @param {string[]} [providerPriority]
+ * @returns {Map<string, number>}
+ */
+function buildPriorityMap(providerPriority) {
+	const map = new Map()
+	if (!providerPriority || providerPriority.length === 0) {
+		return map
+	}
+	for (let i = 0; i < providerPriority.length; i++) {
+		map.set(providerPriority[i], providerPriority.length - i)
+	}
+	return map
+}
+
+/**
+ * Extracts remediations from the sources/dependencies/issues tree of a provider report.
+ * @param {object} providerReport
+ * @param {string} providerName
+ * @param {number} providerRank - numeric priority rank for this provider
+ * @param {Map<string, object>} remediationsByDep - accumulator keyed by dependency PURL
+ * @param {Map<string, number>} rankByDep - tracks current winning rank per dependency
+ */
+function extractFromSources(providerReport, providerName, providerRank, remediationsByDep, rankByDep) {
+	if (!providerReport.sources) {
+		return
+	}
+
+	for (const [sourceName, sourceReport] of Object.entries(providerReport.sources)) {
+		if (!sourceReport.dependencies) {
+			continue
+		}
+		for (const dep of sourceReport.dependencies) {
+			if (!dep.issues) {
+				continue
+			}
+			for (const issue of dep.issues) {
+				processIssueRemediation(
+					issue, dep, providerName, sourceName, providerRank, remediationsByDep, rankByDep
+				)
+			}
+		}
+	}
+}
+
+/**
+ * Processes a single issue's remediation data and merges it into the accumulator.
+ * @param {object} issue - issue object containing remediation and CVE data
+ * @param {object} dep - dependency object containing the ref PURL
+ * @param {string} providerName
+ * @param {string} sourceName
+ * @param {number} providerRank
+ * @param {Map<string, object>} remediationsByDep
+ * @param {Map<string, number>} rankByDep
+ */
+function processIssueRemediation(issue, dep, providerName, sourceName, providerRank, remediationsByDep, rankByDep) {
+	const fixedInPurl = getFixedInPurl(issue)
+	if (!fixedInPurl) {
+		return
+	}
+
+	const depPurl = dep.ref
+	if (!depPurl) {
+		return
+	}
+
+	let parsedDep
+	let parsedFix
+	try {
+		parsedDep = PackageURL.fromString(depPurl)
+		parsedFix = PackageURL.fromString(fixedInPurl)
+	} catch {
+		return
+	}
+
+	const fixedInVersion = parsedFix.version
+	if (!fixedInVersion) {
+		return
+	}
+
+	const cveId = issue.id || issue.cve
+	const severity = issue.severity || 'UNKNOWN'
+	const advisories = extractAdvisories(issue)
+
+	const existing = remediationsByDep.get(depPurl)
+
+	if (!existing) {
+		remediationsByDep.set(depPurl, {
+			purl: depPurl,
+			groupId: parsedDep.namespace || '',
+			artifactId: parsedDep.name,
+			currentVersion: parsedDep.version || '',
+			fixedInVersion,
+			fixedInPurl,
+			provider: providerName,
+			source: sourceName,
+			advisories,
+			severity: severity.toUpperCase(),
+			cves: cveId ? [cveId] : [],
+		})
+		rankByDep.set(depPurl, providerRank)
+		return
+	}
+
+	if (cveId && !existing.cves.includes(cveId)) {
+		existing.cves.push(cveId)
+	}
+
+	mergeAdvisories(existing.advisories, advisories)
+
+	const existingRank = rankByDep.get(depPurl)
+
+	if (providerRank > existingRank) {
+		existing.fixedInVersion = fixedInVersion
+		existing.fixedInPurl = fixedInPurl
+		existing.provider = providerName
+		existing.source = sourceName
+		existing.severity = higherSeverity(existing.severity, severity)
+		rankByDep.set(depPurl, providerRank)
+	} else if (providerRank === existingRank) {
+		if (compareVersions(fixedInVersion, existing.fixedInVersion) > 0) {
+			existing.fixedInVersion = fixedInVersion
+			existing.fixedInPurl = fixedInPurl
+			existing.provider = providerName
+			existing.source = sourceName
+		}
+		existing.severity = higherSeverity(existing.severity, severity)
+	}
+}
+
+/**
+ * Extracts remediations from the recommendations section of a provider report.
+ * Merges CVEs and advisories into existing entries when present.
+ * @param {object} providerReport
+ * @param {string} providerName
+ * @param {number} providerRank
+ * @param {Map<string, object>} remediationsByDep
+ * @param {Map<string, number>} rankByDep
+ */
+function extractFromRecommendations(providerReport, providerName, providerRank, remediationsByDep, rankByDep) {
+	if (!providerReport.recommendations || !providerReport.recommendations.dependencies) {
+		return
+	}
+
+	for (const dep of providerReport.recommendations.dependencies) {
+		if (!dep.recommendation || !dep.ref) {
+			continue
+		}
+
+		const recommendedPurl = dep.recommendation.ref || dep.recommendation
+		if (typeof recommendedPurl !== 'string') {
+			continue
+		}
+
+		let parsedDep
+		let parsedRec
+		try {
+			parsedDep = PackageURL.fromString(dep.ref)
+			parsedRec = PackageURL.fromString(recommendedPurl)
+		} catch {
+			continue
+		}
+
+		const fixedInVersion = parsedRec.version
+		if (!fixedInVersion) {
+			continue
+		}
+
+		const depPurl = dep.ref
+		const existing = remediationsByDep.get(depPurl)
+
+		if (!existing) {
+			remediationsByDep.set(depPurl, {
+				purl: depPurl,
+				groupId: parsedDep.namespace || '',
+				artifactId: parsedDep.name,
+				currentVersion: parsedDep.version || '',
+				fixedInVersion,
+				fixedInPurl: recommendedPurl,
+				provider: providerName,
+				source: 'recommendation',
+				advisories: [],
+				severity: 'UNKNOWN',
+				cves: [],
+			})
+			rankByDep.set(depPurl, providerRank)
+			continue
+		}
+
+		const existingRank = rankByDep.get(depPurl)
+
+		if (providerRank > existingRank) {
+			existing.fixedInVersion = fixedInVersion
+			existing.fixedInPurl = recommendedPurl
+			existing.provider = providerName
+			existing.source = 'recommendation'
+			rankByDep.set(depPurl, providerRank)
+		} else if (providerRank === existingRank) {
+			if (compareVersions(fixedInVersion, existing.fixedInVersion) > 0) {
+				existing.fixedInVersion = fixedInVersion
+				existing.fixedInPurl = recommendedPurl
+				existing.provider = providerName
+				existing.source = 'recommendation'
+			}
+		}
+	}
+}
+
+/**
+ * Gets the fixedIn PURL from an issue's remediation, preferring trustedContent.
+ * @param {object} issue
+ * @returns {string|undefined}
+ */
+function getFixedInPurl(issue) {
+	if (!issue.remediation) {
+		return undefined
+	}
+	if (issue.remediation.trustedContent && issue.remediation.trustedContent.ref) {
+		return issue.remediation.trustedContent.ref
+	}
+	if (issue.remediation.fixedIn) {
+		return issue.remediation.fixedIn
+	}
+	return undefined
+}
+
+/**
+ * Extracts advisory objects from an issue.
+ * @param {object} issue
+ * @returns {Array<{id: string, url: string}>}
+ */
+function extractAdvisories(issue) {
+	const advisories = []
+	if (issue.remediation && issue.remediation.trustedContent) {
+		const tc = issue.remediation.trustedContent
+		if (tc.advisory) {
+			advisories.push({
+				id: tc.advisory.id || tc.advisory,
+				url: tc.advisory.url || '',
+			})
+		}
+	}
+	if (issue.advisories) {
+		for (const adv of issue.advisories) {
+			advisories.push({
+				id: adv.id || adv,
+				url: adv.url || '',
+			})
+		}
+	}
+	return advisories
+}
+
+/**
+ * Merges new advisories into existing list, avoiding duplicates by id.
+ * @param {Array<{id: string, url: string}>} existing
+ * @param {Array<{id: string, url: string}>} incoming
+ */
+function mergeAdvisories(existing, incoming) {
+	const seen = new Set(existing.map(a => a.id))
+	for (const adv of incoming) {
+		if (!seen.has(adv.id)) {
+			existing.push(adv)
+			seen.add(adv.id)
+		}
+	}
+}
+
+/**
+ * Compares two version strings segment by segment.
+ * Returns positive if a > b, negative if a < b, zero if equal.
+ * Falls back to lexicographic comparison for non-numeric segments.
+ * @param {string} a
+ * @param {string} b
+ * @returns {number}
+ */
+function compareVersions(a, b) {
+	const partsA = a.split('.').map(s => parseInt(s, 10) || 0)
+	const partsB = b.split('.').map(s => parseInt(s, 10) || 0)
+	const len = Math.max(partsA.length, partsB.length)
+	for (let i = 0; i < len; i++) {
+		const diff = (partsA[i] || 0) - (partsB[i] || 0)
+		if (diff !== 0) {
+			return diff
+		}
+	}
+	return a.localeCompare(b)
+}
+
+const SEVERITY_ORDER = ['UNKNOWN', 'LOW', 'MEDIUM', 'HIGH', 'CRITICAL']
+
+/**
+ * Returns the higher of two severity strings, normalized to uppercase.
+ * @param {string} a
+ * @param {string} b
+ * @returns {string}
+ */
+function higherSeverity(a, b) {
+	const upperA = a.toUpperCase()
+	const upperB = b.toUpperCase()
+	const indexA = SEVERITY_ORDER.indexOf(upperA)
+	const indexB = SEVERITY_ORDER.indexOf(upperB)
+	return indexA >= indexB ? upperA : upperB
+}