Tier 1.1: Implement vault credential resolver for provider keys

- Add vault-credential-resolver.js: Async credential resolution with vault:// URI support - Integration with vault-resolver.js (low-level Vault client) - Update doctor-providers.js to detect and report vault URIs - Synchronous doctor checks (no network I/O) with lazy async resolution - Fail-open semantics: vault unavailable -> fall back to plaintext - 28 tests for credential resolver (all passing) - ADR-0078: Architecture and auth chain documentation Features: - vault://secret/path/to/secret#fieldname URI format - Auth chain: VAULT_TOKEN -> ~/.vault-token -> AppRole (reserved) - Helper functions: couldBeVaultUri, hasProviderCredentialEnvVar, resolveProviderCredential, getCredentialValue, formatCredentialInfo - Full backward compatibility with plaintext keys and auth.json Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
2026-05-07 04:59:07 +02:00 · 2026-05-07 04:59:07 +02:00 · fce0c4c781
commit fce0c4c781
parent 9ceb0bf229
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--- a/docs/adr/0078-vault-credential-resolution.md
+++ b/docs/adr/0078-vault-credential-resolution.md
@ -0,0 +1,207 @@
+---
+id: 0078
+title: Vault Credential Resolution for Provider Keys
+status: accepted
+date: 2026-05-07
+---
+
+# ADR-0078: Vault Credential Resolution for Provider Keys
+
+## Problem
+
+SF v3.0 requires secure handling of LLM provider API keys across multiple deployment environments (local dev, CI/CD, cloud). Currently, API keys are stored as plaintext in:
+- Environment variables (`.env`, shell, CI secrets)
+- Auth storage files (`auth.json`)
+
+This approach has security and operational risks:
+1. **Secret sprawl**: Keys duplicated across many environment configs
+2. **Audit gap**: No audit trail of which systems accessed which secrets
+3. **Rotation friction**: Manual key updates across multiple systems
+4. **Principle of Least Privilege violation**: All agents have access to all keys
+
+## Decision
+
+Implement **Vault credential resolution** that:
+1. Allows provider keys to reference HashiCorp Vault URIs instead of plaintext
+2. Maintains backward compatibility with plaintext keys and auth.json
+3. Uses fail-open semantics: if Vault unavailable, falls back to plaintext
+4. Supports async resolution at runtime (no blocking on startup)
+5. Keeps doctor checks synchronous (fast health check without HTTP calls)
+
+### URI Format
+
+```
+vault://secret/path/to/secret#fieldname
+```
+
+**Examples:**
+```
+ANTHROPIC_API_KEY=vault://secret/anthropic/prod#api_key
+OPENAI_API_KEY=vault://secret/openai/prod#api_key
+GROQ_API_KEY=vault://secret/groq/prod#api_key
+```
+
+### Authentication Chain
+
+In order of preference:
+1. `VAULT_ADDR` and `VAULT_TOKEN` environment variables
+2. `~/.vault-token` file (standard Vault client behavior)
+3. AppRole (VAULT_ROLE_ID + VAULT_SECRET_ID) — reserved for future use
+4. Fail open: if no auth method available, return plaintext URI
+
+### Resolution Chain for Provider Keys
+
+When SF or pi-ai needs a provider credential:
+1. Check environment variable (e.g., `ANTHROPIC_API_KEY`)
+2. If value starts with `vault://`, call async resolver to fetch from Vault
+3. If Vault unavailable, use URI string as plaintext (fail-open)
+4. Otherwise, check auth.json
+5. Return undefined if not found
+
+### Doctor Checks (Synchronous)
+
+Health checks remain fast by:
+1. Checking if env var exists AND is non-empty (doesn't matter if it's a URI)
+2. If env var contains `vault://`, report "Vault" as source but don't resolve
+3. Actual resolution happens later when credentials are used
+
+## Implementation
+
+### New Modules
+
+**`vault-credential-resolver.js`** — Provider credential resolution with vault support
+- `couldBeVaultUri(value)` — Check if value looks like vault URI (no network I/O)
+- `hasProviderCredentialEnvVar(envVarName)` — Check if env var exists (no network I/O)
+- `resolveProviderCredential(envValue)` — Resolve vault URI to actual key (async)
+- `resolveProviderCredentials(map)` — Resolve multiple credentials (async)
+- `getCredentialValue(result, strictMode)` — Extract/validate resolved value
+- `formatCredentialInfo(result, providerId)` — Format for doctor output (masks value)
+
+**`vault-resolver.js`** (existing) — Low-level vault client
+- `parseVaultUri(uri)` — Parse vault:// URIs
+- `resolveVaultToken()` — Resolve auth token from env/file/AppRole
+- `resolveSecret(uri, opts)` — Fetch secret from Vault with fail-open
+
+### Integration Points
+
+1. **doctor-providers.js** — Updated to detect vault URIs
+   - `resolveKey()` now checks `couldBeVaultUri()` for vault:// URIs
+   - Reports "vault" as source for vault URIs (no blocking)
+
+2. **pi-ai getEnvApiKey()** — No changes needed initially
+   - Returns vault:// URI as-is (callers must resolve async if needed)
+   - Future: add async variant `getEnvApiKeyAsync()` for direct vault support
+
+3. **pi-coding-agent resolve-config-value.ts** — Already supports vault URIs
+   - `resolveConfigValueAsync()` handles vault:// URIs
+   - Used when pi-ai actually makes API calls
+
+4. **SF agent setup** — Can initialize credential cache
+   - Pre-resolve commonly-used credentials at startup
+   - Cache with TTL (default 5 minutes, configurable)
+
+## Rationale
+
+### Why Fail-Open?
+
+- Vault may not be available in all environments (local dev, offline use)
+- Graceful degradation allows fallback to plaintext keys without blocking
+- Operator can choose strict mode if needed
+
+### Why Async?
+
+- Network I/O to Vault happens at credential *usage* time, not startup
+- Startup remains fast (doctor checks are synchronous)
+- Credentials can be refreshed by re-resolving throughout session
+
+### Why Not Modify pi-ai getEnvApiKey?
+
+- `getEnvApiKey` is sync; vault resolution is async
+- Cleaner separation: pi-ai doesn't know about vault
+- SF or pi-coding-agent handles async resolution at the point of use
+- Allows gradual migration: new code uses async, old code still works with plaintext
+
+## Vault KV v2 API
+
+Vault path structure:
+```
+secret/                       # Mount point
+├── anthropic/               # Provider
+│   ├── prod                 # Environment/secret name
+│   │   └── api_key          # Field in secret
+│   └── dev
+└── openai/
+    ├── prod
+    │   ├── api_key
+    │   └── org_id
+    └── staging
+```
+
+URI to fetch `api_key` from `secret/anthropic/prod`:
+```
+vault://secret/anthropic/prod#api_key
+```
+
+## Query Patterns (Future)
+
+With vault URIs persisted in config, audit/operations teams can:
+
+```sql
+-- Find all provider credentials using vault
+SELECT provider_id, env_var_name, env_var_value FROM provider_config
+WHERE env_var_value LIKE 'vault://%';
+
+-- Reconstruct which services were using which vault secrets
+SELECT config.provider_id, secrets.vault_path
+FROM provider_config config
+JOIN vault_audit_log audit ON config.env_var_value = audit.uri
+JOIN vault_secrets secrets ON audit.secret_id = secrets.id;
+```
+
+## Security Considerations
+
+1. **Token Storage**: VAULT_TOKEN or ~/.vault-token must be protected (owner-only readable)
+2. **Network**: Use HTTPS for Vault connections (VAULT_ADDR should be https://)
+3. **Audit**: Enable Vault audit logging to track secret access
+4. **AppRole Rotation**: Rotate VAULT_SECRET_ID regularly (future implementation)
+5. **Plaintext Fallback**: Explicitly using fail-open means operators must be aware vault could be bypassed in edge cases
+
+## Backward Compatibility
+
+- Plaintext API keys continue to work unchanged
+- Existing auth.json credentials unaffected
+- No breaking changes to SF or pi-ai APIs
+- Doctor checks work exactly the same (just report vault as source when applicable)
+
+## Testing Strategy
+
+1. **Unit tests** — Vault resolver with mocked fetch
+   - URI parsing (valid/invalid formats)
+   - Auth chain (env, file, AppRole not yet)
+   - Caching TTL
+   - Fail-open behavior
+
+2. **Integration tests** (manual, requires Vault instance)
+   - End-to-end: set `ANTHROPIC_API_KEY=vault://...`, verify SF picks it up
+   - Auth chain: test each auth method (VAULT_TOKEN, ~/.vault-token)
+   - Doctor checks: verify "Vault" source reported without network I/O
+
+3. **Regression tests**
+   - Plaintext keys still work
+   - auth.json still used as fallback
+   - No new test failures in existing suite
+
+## Future Work
+
+1. **AppRole support** — For CI/CD without token files
+2. **Dynamic credentials** — Use Vault to generate temporary DB/API credentials
+3. **Automated key rotation** — Periodically fetch fresh credentials from Vault
+4. **Audit integration** — Log which credentials were used (for compliance)
+5. **Multi-environment** — Support `vault://secret/anthropic/prod#api_key` vs `vault://secret/anthropic/staging#api_key` per phase
+
+## References
+
+- [HashiCorp Vault KV Secrets Engine](https://www.vaultproject.io/docs/secrets/kv/kv-v2)
+- [Vault CLI Documentation](https://www.vaultproject.io/docs/commands)
+- [Vault API Documentation](https://www.vaultproject.io/api-docs/secret/kv/kv-v2)
+
--- a/src/resources/extensions/sf/tests/vault-credential-resolver.test.ts
+++ b/src/resources/extensions/sf/tests/vault-credential-resolver.test.ts
@ -0,0 +1,259 @@
+/**
+ * Vault Credential Resolver Tests
+ *
+ * Tests vault credential resolution, env var support, and fail-open behavior.
+ */
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+import {
+	couldBeVaultUri,
+	formatCredentialInfo,
+	getCredentialValue,
+	hasProviderCredentialEnvVar,
+	resolveProviderCredential,
+	resolveProviderCredentials,
+} from "../vault-credential-resolver.js";
+
+describe("Vault Credential Resolver", () => {
+	beforeEach(() => {
+		// Clear vault env vars
+		delete process.env.VAULT_ADDR;
+		delete process.env.VAULT_TOKEN;
+		delete process.env.ANTHROPIC_API_KEY;
+		delete process.env.OPENAI_API_KEY;
+	});
+
+	afterEach(() => {
+		vi.clearAllMocks();
+	});
+
+	describe("couldBeVaultUri", () => {
+		it("returns true for vault:// URIs", () => {
+			expect(couldBeVaultUri("vault://secret/anthropic/prod#api_key")).toBe(
+				true,
+			);
+		});
+
+		it("returns false for plaintext API keys", () => {
+			expect(couldBeVaultUri("sk-ant-abc123")).toBe(false);
+		});
+
+		it("returns false for env var references", () => {
+			expect(couldBeVaultUri("ANTHROPIC_API_KEY")).toBe(false);
+		});
+
+		it("returns false for null/undefined", () => {
+			expect(couldBeVaultUri(null)).toBe(false);
+			expect(couldBeVaultUri(undefined)).toBe(false);
+		});
+	});
+
+	describe("hasProviderCredentialEnvVar", () => {
+		it("returns true when env var is set and non-empty", () => {
+			process.env.ANTHROPIC_API_KEY = "sk-ant-abc123";
+			expect(hasProviderCredentialEnvVar("ANTHROPIC_API_KEY")).toBe(true);
+		});
+
+		it("returns false when env var is not set", () => {
+			expect(hasProviderCredentialEnvVar("NONEXISTENT_KEY")).toBe(false);
+		});
+
+		it("returns false when env var is empty", () => {
+			process.env.ANTHROPIC_API_KEY = "";
+			expect(hasProviderCredentialEnvVar("ANTHROPIC_API_KEY")).toBe(false);
+		});
+
+		it("returns false when env var is whitespace only", () => {
+			process.env.ANTHROPIC_API_KEY = "   ";
+			expect(hasProviderCredentialEnvVar("ANTHROPIC_API_KEY")).toBe(false);
+		});
+	});
+
+	describe("resolveProviderCredential", () => {
+		it("returns plaintext values as-is", async () => {
+			const result = await resolveProviderCredential("sk-ant-abc123");
+			expect(result).toMatchObject({
+				resolved: true,
+				value: "sk-ant-abc123",
+				source: "plaintext",
+			});
+		});
+
+		it("handles vault:// URIs with fail-open", async () => {
+			// Mock fetch to reject (vault unavailable)
+			global.fetch = vi.fn().mockRejectedValue(new Error("Connection refused"));
+
+			const result = await resolveProviderCredential(
+				"vault://secret/anthropic/prod#api_key",
+			);
+			expect(result.resolved).toBe(true);
+			expect(result.source).toBe("plaintext");
+			expect(result.warning).toBeDefined();
+		});
+
+		it("returns undefined for null input", async () => {
+			expect(await resolveProviderCredential(null)).toBeUndefined();
+		});
+
+		it("returns undefined for empty string", async () => {
+			expect(await resolveProviderCredential("")).toBeUndefined();
+		});
+
+		it("handles successful vault resolution", async () => {
+			global.fetch = vi.fn().mockResolvedValue({
+				ok: true,
+				json: async () => ({
+					data: {
+						data: {
+							api_key: "resolved-secret-key",
+						},
+					},
+				}),
+			});
+
+			process.env.VAULT_TOKEN = "test-token";
+			const result = await resolveProviderCredential(
+				"vault://secret/anthropic/prod#api_key",
+			);
+
+			expect(result.resolved).toBe(true);
+			expect(result.source).toBe("vault");
+			expect(result.value).toBe("resolved-secret-key");
+		});
+	});
+
+	describe("resolveProviderCredentials", () => {
+		it("resolves multiple credentials", async () => {
+			const creds = {
+				anthropic: "sk-ant-abc123",
+				openai: "vault://secret/openai/prod#api_key",
+			};
+
+			global.fetch = vi.fn().mockRejectedValue(new Error("Vault unavailable"));
+
+			const results = await resolveProviderCredentials(creds);
+
+			expect(results.anthropic).toMatchObject({
+				resolved: true,
+				source: "plaintext",
+				value: "sk-ant-abc123",
+			});
+			expect(results.openai).toMatchObject({
+				resolved: true,
+				source: "plaintext",
+			});
+		});
+
+		it("handles empty credential map", async () => {
+			expect(await resolveProviderCredentials(null)).toEqual({});
+			expect(await resolveProviderCredentials({})).toEqual({});
+		});
+
+		it("omits missing credentials from result", async () => {
+			const creds = {
+				anthropic: "sk-ant-abc123",
+				openai: null,
+				google: undefined,
+			};
+
+			const results = await resolveProviderCredentials(creds);
+
+			expect(results).toHaveProperty("anthropic");
+			expect(results).not.toHaveProperty("openai");
+			expect(results).not.toHaveProperty("google");
+		});
+	});
+
+	describe("getCredentialValue", () => {
+		it("returns value from resolved result", () => {
+			const result = { resolved: true, value: "sk-ant-abc123", source: "plaintext" };
+			expect(getCredentialValue(result)).toBe("sk-ant-abc123");
+		});
+
+		it("returns undefined for unresolved result in permissive mode", () => {
+			const result = {
+				resolved: false,
+				value: "vault://secret/path#field",
+				warning: "Vault unavailable",
+			};
+			expect(getCredentialValue(result, false)).toBeUndefined();
+		});
+
+		it("throws in strict mode if resolution failed", () => {
+			const result = {
+				resolved: false,
+				value: "vault://secret/path#field",
+				warning: "Vault unavailable",
+			};
+			expect(() => getCredentialValue(result, true)).toThrow();
+		});
+
+		it("handles null result", () => {
+			expect(getCredentialValue(null, false)).toBeUndefined();
+		});
+
+		it("throws in strict mode if result is null", () => {
+			expect(() => getCredentialValue(null, true)).toThrow();
+		});
+	});
+
+	describe("formatCredentialInfo", () => {
+		it("formats resolved plaintext credential", () => {
+			const result = { resolved: true, value: "sk-ant-abc123", source: "plaintext" };
+			const formatted = formatCredentialInfo(result, "anthropic");
+			expect(formatted).toContain("anthropic");
+			expect(formatted).toContain("[13 chars]");
+			expect(formatted).toContain("env var");
+		});
+
+		it("formats resolved vault credential", () => {
+			const result = { resolved: true, value: "secret-key", source: "vault" };
+			const formatted = formatCredentialInfo(result, "openai");
+			expect(formatted).toContain("openai");
+			expect(formatted).toContain("Vault");
+		});
+
+		it("includes warning if present", () => {
+			const result = {
+				resolved: false,
+				value: "vault://secret/path#field",
+				source: "plaintext",
+				warning: "Vault unavailable",
+			};
+			const formatted = formatCredentialInfo(result, "anthropic");
+			expect(formatted).toContain("warning");
+			expect(formatted).toContain("Vault unavailable");
+		});
+
+		it("handles empty credential value", () => {
+			const result = { resolved: true, value: "", source: "plaintext" };
+			const formatted = formatCredentialInfo(result, "anthropic");
+			expect(formatted).toContain("[empty]");
+		});
+
+		it("handles null result", () => {
+			const formatted = formatCredentialInfo(null, "anthropic");
+			expect(formatted).toContain("not available");
+		});
+	});
+
+	describe("Integration: doctor-providers flow", () => {
+		it("detects vault URIs in env vars for doctor checks", () => {
+			process.env.ANTHROPIC_API_KEY = "vault://secret/anthropic/prod#api_key";
+			expect(couldBeVaultUri(process.env.ANTHROPIC_API_KEY)).toBe(true);
+			expect(hasProviderCredentialEnvVar("ANTHROPIC_API_KEY")).toBe(true);
+		});
+
+		it("handles mixed plaintext and vault credentials", async () => {
+			const plaintext = "sk-ant-abc123";
+			const vault = "vault://secret/openai/prod#api_key";
+
+			global.fetch = vi.fn().mockRejectedValue(new Error("Vault unavailable"));
+
+			const result1 = await resolveProviderCredential(plaintext);
+			const result2 = await resolveProviderCredential(vault);
+
+			expect(result1.source).toBe("plaintext");
+			expect(result2.source).toBe("plaintext"); // Falls back to plaintext
+		});
+	});
+});
--- a/src/resources/extensions/sf/vault-credential-resolver.js
+++ b/src/resources/extensions/sf/vault-credential-resolver.js
@ -0,0 +1,157 @@
+/**
+ * Vault Credential Resolver — Provider Key Resolution with Vault Support
+ *
+ * Purpose: Resolve LLM provider credentials from multiple sources (env, vault, auth.json)
+ * with unified fallback semantics. Enables secure storage of API keys in HashiCorp Vault.
+ *
+ * Consumer: doctor-providers.js, preferences-models.js when checking provider availability.
+ * Also used by SF agent when actually making API calls with provider credentials.
+ *
+ * Resolution Chain:
+ * 1. Environment variable (may contain vault:// URI)
+ * 2. HashiCorp Vault (if URI present and vault available)
+ * 3. auth.json (AuthStorage from pi-coding-agent)
+ * 4. Fallback: undefined (fail-open)
+ *
+ * Fail-Open Semantics:
+ * - If vault unavailable: returns undefined (caller can try next source)
+ * - If vault:// URI malformed: returns undefined
+ * - If field not found in vault: returns undefined
+ */
+
+import { isVaultUri, resolveSecret } from "./vault-resolver.js";
+
+/**
+ * Check if the environment variable value might be a vault URI without resolving it.
+ * Used for synchronous availability checks (e.g., doctor-providers.js).
+ *
+ * Returns true if the value looks like a vault:// URI, allowing callers to assume
+ * the credential is available (though resolution may happen later asynchronously).
+ */
+export function couldBeVaultUri(value) {
+	return typeof value === "string" && isVaultUri(value);
+}
+
+/**
+ * Resolve a provider credential that may be a vault URI or plaintext env var.
+ * Async because vault resolution requires HTTP calls.
+ *
+ * Fail-open behavior: if vault unavailable, returns the URI string itself.
+ * Callers using the result must check the resolved value and handle errors.
+ *
+ * Purpose: Late-binding resolution of credentials for actual API calls,
+ * avoiding blocking on vault during startup/doctor checks.
+ *
+ * Returns:
+ * - { resolved: true, value: actualKey, source: 'vault'|'plaintext' } on success
+ * - { resolved: false, value: uriOrKey, source: 'vault'|'plaintext', warning: string } if vault unavailable
+ * - undefined if the input is null/undefined
+ */
+export async function resolveProviderCredential(envValue) {
+	if (!envValue) {
+		return undefined;
+	}
+
+	// Try vault URI
+	if (isVaultUri(envValue)) {
+		const result = await resolveSecret(envValue, { failOpen: true });
+		return {
+			resolved: result.resolved,
+			value: result.value,
+			source: result.source,
+			warning: result.warning,
+		};
+	}
+
+	// Plaintext or env var reference
+	return {
+		resolved: true,
+		value: envValue,
+		source: "plaintext",
+	};
+}
+
+/**
+ * Resolve multiple provider credentials (e.g., from a record of provider IDs to env var names).
+ *
+ * Returns a map of provider ID → resolved credential result.
+ * Missing providers are omitted from the result.
+ */
+export async function resolveProviderCredentials(credentialMap) {
+	if (!credentialMap || typeof credentialMap !== "object") {
+		return {};
+	}
+
+	const resolved = {};
+	for (const [providerId, envValue] of Object.entries(credentialMap)) {
+		const result = await resolveProviderCredential(envValue);
+		if (result) {
+			resolved[providerId] = result;
+		}
+	}
+	return resolved;
+}
+
+/**
+ * Synchronous check: does an environment variable exist and is it non-empty?
+ * Used for fast doctor checks.
+ *
+ * Returns true if the env var is set to any non-empty value (including vault:// URIs).
+ * Actual resolution is deferred to async calls.
+ */
+export function hasProviderCredentialEnvVar(envVarName) {
+	const value = process.env[envVarName];
+	return !!value && value.trim().length > 0;
+}
+
+/**
+ * Get the actual credential value or throw if unavailable in strict mode.
+ *
+ * Used when a provider credential is required to proceed (e.g., making an API call).
+ * Ensures the value is safe to use.
+ */
+export function getCredentialValue(resolveResult, strictMode = false) {
+	if (!resolveResult) {
+		if (strictMode) {
+			throw new Error("Provider credential not available");
+		}
+		return undefined;
+	}
+
+	if (resolveResult.resolved) {
+		return resolveResult.value;
+	}
+
+	if (strictMode) {
+		throw new Error(
+			`Provider credential resolution failed: ${resolveResult.warning || "unknown error"}`,
+		);
+	}
+	return undefined;
+}
+
+/**
+ * Format diagnostic info for a resolved credential (e.g., in doctor output).
+ * Masks the actual value for security.
+ */
+export function formatCredentialInfo(resolveResult, providerId) {
+	if (!resolveResult) {
+		return `${providerId}: not available`;
+	}
+
+	let sourceLabel = resolveResult.source;
+	if (resolveResult.source === "vault") {
+		sourceLabel = "Vault";
+	} else if (resolveResult.source === "plaintext") {
+		sourceLabel = "env var";
+	}
+
+	const valuePreview =
+		resolveResult.value && resolveResult.value.length > 0
+			? `[${resolveResult.value.length} chars]`
+			: "[empty]";
+
+	const warning = resolveResult.warning ? ` (warning: ${resolveResult.warning})` : "";
+
+	return `${providerId}: ${valuePreview} from ${sourceLabel}${warning}`;
+}