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Merged
merged 4 commits into from
Mar 25, 2025
Merged

Exposing functions to independently apply actions pre-request and post-response #94

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5011e1c
Factor out getActions method and export it
jordan83 Mar 24, 2025
bafc377
exposing granular action application methods
jordan83 Mar 24, 2025
d43d53e
Addressing code review:
jordan83 Mar 25, 2025
e946b22
removing outdated comments
jordan83 Mar 25, 2025
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128 changes: 127 additions & 1 deletion src/index.test.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -21,6 +21,7 @@ import { expect, test, vi, Mock } from "vitest";

import {
applyActions,
fetchActions,
callCreateAssessment,
callListFirewallPolicies,
createPartialEventWithSiteInfo,
Expand All @@ -39,6 +40,8 @@ import {
EdgeResponseInit,
FirewallPolicy,
Event,
applyPreRequestActions,
applyPostResponseActions,
} from "./index";

import { FetchApiRequest, FetchApiResponse } from "./fetchApi";
Expand Down Expand Up @@ -83,7 +86,8 @@ class TestContext extends RecaptchaContext {
log_messages: Array<[LogLevel, string[]]> = [];

constructor(config: RecaptchaConfig) {
super(config);
// Deep copy the config so it can be modified independently.
super(JSON.parse(JSON.stringify(config)));
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the config should already be a JS object? why is this necessary?

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The config needed to be deep-copied. It's global and there are tests that modify it so I had failures when making new tests. We can also have a function that creates a new literal. Do you have a preference?

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wild that there is no good way to do a deep copy.

I've been using the spread operator {...config} for stuff like this. though in cases where the object is nested (not here) it doesn't work.

Object.assign({}, config) would also work here (though (not relevant) strips methods and prototypes)

or consider just adding a comment so the motivation for the serialization is clear

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Adding a comment for now. We can always revisit.

}

createRequest(url: string, options: any): EdgeRequest {
Expand Down Expand Up @@ -344,6 +348,7 @@ test("ApplyActions-setHeader", async () => {
expect(resp.text()).toEqual("<HTML>Hello World</HTML>");
expect(fetch).toHaveBeenCalledTimes(1);
});

test("ApplyActions-redirect", async () => {
const context = new TestContext(testConfig);
const req = new FetchApiRequest("https://www.example.com/originalreq");
Expand Down Expand Up @@ -1087,6 +1092,7 @@ test("processRequest-dump", async () => {
["debug", ["[rpc] listFirewallPolicies (ok)"]],
["debug", ["local assessment succeeded"]],
["debug", ["terminalAction: allow"]],
["debug", ["Applying response actions, ignoring request action"]],
],
exceptions: [],
create_assessment_headers: [],
Expand Down Expand Up @@ -1369,3 +1375,123 @@ test("DebugTrace-format", () => {
"list_firewall_policies_status=ok;policy_count=10;site_key_used=session;site_keys_present=asce;empty_config=apikey,endpoint;performance_counters=",
);
});

test("fetchActions-localAssessment", async () => {
const context = new TestContext(testConfig);
context.config.sessionJsInjectPath = "/teste2e;/another/path";
const req = new FetchApiRequest("https://www.example.com/teste2e");
const testPolicies = [
{
name: "test-policy",
description: "test-description",
path: "/teste2e",
actions: [{ block: {} }],
},
{
name: "test-policy2",
description: "test-description2",
path: "/teste2e",
actions: [{ redirect: {} }],
},
];
vi.stubGlobal("fetch", vi.fn());
(fetch as Mock).mockImplementationOnce(() =>
Promise.resolve({
status: 200,
headers: new Headers(),
json: () => Promise.resolve({ firewallPolicies: testPolicies }),
}),
);
const actions = await fetchActions(context, req);
expect(actions).toEqual([
{
injectjs: {},
},
{
block: {},
},
]);
expect(fetch).toHaveBeenCalledTimes(1);
});

test("fetchActions-createAssessment", async () => {
const context = new TestContext(testConfig);
const req = new FetchApiRequest("https://www.example.com/testlocal");
vi.stubGlobal("fetch", vi.fn());
(fetch as Mock)
.mockImplementationOnce((req) => {
expect(req.url).toEqual("https://recaptchaenterprise.googleapis.com/v1/projects/12345/fetchFirewallPolicies");
const testPolicies = [
{
name: "test-policy",
description: "test-description",
path: "/testlocal",
condition: "test-condition",
actions: [{ block: {} }],
},
];
Promise.resolve({
status: 200,
headers: new Headers(),
json: () => Promise.resolve({ firewallPolicies: testPolicies }),
});
})
.mockImplementationOnce((req) => {
expect(req.url).toEqual("https://recaptchaenterprise.googleapis.com/v1/projects/12345/assessments?key=abc123");
return Promise.resolve({
status: 200,
headers: new Headers(),
json: () =>
Promise.resolve({
name: "projects/12345/assessments/1234567890",
firewallPolicyAssessment: {
firewallPolicy: {
actions: [{ block: {} }],
},
},
}),
});
});
const actions = await fetchActions(context, req);
expect(fetch).toHaveBeenCalledTimes(2);
expect(actions).toEqual([
{
block: {},
},
]);
});

test("applyPreRequestActions - terminal", async () => {
const context = new TestContext(testConfig);
const req = new FetchApiRequest("https://www.example.com/teste2e");
const resp = (await applyPreRequestActions(context, req, [{ block: {} }])) as EdgeResponse;
expect(resp.status).toEqual(403);
});

test("applyPreRequestActions - non-terminal", async () => {
const context = new TestContext(testConfig);
const req = new FetchApiRequest("https://www.example.com/teste2e");
expect(req.getHeader("my-custom-header")).toBeNull();
const resp = await applyPreRequestActions(context, req, [
{
setHeader: {
key: "my-custom-header",
value: "test123",
},
},
]);
expect(resp).toBeNull();
expect(req.getHeader("my-custom-header")).toEqual("test123");
});

test("applyPostResponseActions", async () => {
const context = new TestContext(testConfig);
const inputResp: Promise<EdgeResponse> = Promise.resolve({
status: 200,
headers: new Headers(),
text: () => "<HTML>Hello World</HTML>",
});

const resp = await applyPostResponseActions(context, await inputResp, [{injectjs: {}}]);
expect(await resp.text()).toEqual('<HTML><script src="test.js"/>Hello World</HTML>');
});
3 changes: 3 additions & 0 deletions src/index.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -35,6 +35,9 @@ export { ListFirewallPoliciesResponse, callListFirewallPolicies } from "./listFi

export {
applyActions,
applyPreRequestActions,
applyPostResponseActions,
fetchActions,
evaluatePolicyAssessment,
localPolicyAssessment,
policyConditionMatch,
Expand Down
81 changes: 58 additions & 23 deletions src/policy.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -145,27 +145,24 @@ export async function evaluatePolicyAssessment(context: RecaptchaContext, req: E
}

/**
* Apply actions to a request.
* Apply pre-request actions. If a terminal action is applied it will generate a response
* which will be returned. Non terminal actions will modify the request and return null;
*/
export async function applyActions(
export async function applyPreRequestActions(
context: RecaptchaContext,
req: EdgeRequest,
actions: action.Action[],
): Promise<EdgeResponse> {
): Promise<EdgeResponse | null> {
let terminalAction: action.Action = action.createAllowAction();
const reqNonterminalActions: action.RequestNonTerminalAction[] = [];
const respNonterminalActions: action.ResponseNonTerminalAction[] = [];

// Actions are assumed to be in order of processing. Non-terminal actions must
// be processed before terminal actions, and will be ignored if erroniously
// placed after terminal actions.
filterActions: for (const action of actions) {
for (const action of actions) {
if (isTerminalAction(action)) {
terminalAction = action;
} else if (isRequestNonTerminalAction(action)) {
reqNonterminalActions.push(action);
} else if (isResponseNonTerminalAction(action)) {
respNonterminalActions.push(action);
context.log("debug", "Applying request actions, ignoring response actions");
} else {
/* v8 ignore next */
throw new Error("Unsupported action: " + action);
Expand Down Expand Up @@ -206,23 +203,38 @@ export async function applyActions(
context.log("debug", "reqNonterminal action: setHeader");
if (isSetHeaderAction(action)) {
req.addHeader(action.setHeader.key ?? "", action.setHeader.value ?? "");
continue;
}
if (isSubstituteAction(action)) {
} else if (isSubstituteAction(action)) {
context.log("debug", "reqNonterminal action: substitute");
const url = new URL(req.url);
req.url = `${url.origin}${action.substitute.path}`;
continue;
} else {
/* v8 ignore next 2 lines */
throw new Error("Unsupported pre-request action: " + action);
}
/* v8 ignore next 2 lines */
throw new Error("Unsupported pre-request action: " + action);
}

context.log("debug", "terminalAction: allow");
// Fetch from the backend, whether redirected or not.
let resp = context.fetch_origin(req);
return null;
}

/**
* Apply post response actions. Returns a (possibly modified) response.
*/
export async function applyPostResponseActions(context: RecaptchaContext, resp: EdgeResponse, actions: action.Action[]): Promise<EdgeResponse> {
const respNonterminalActions: action.ResponseNonTerminalAction[] = [];
for (const action of actions) {
if (isTerminalAction(action) || isRequestNonTerminalAction(action)) {
context.log("debug", "Applying response actions, ignoring request action");
} else if (isResponseNonTerminalAction(action)) {
respNonterminalActions.push(action);
} else {
/* v8 ignore next */
throw new Error("Unsupported action: " + action);
}
}

// Handle Post-Response actions.
let modifiedResp = resp;
const once = new Set<string>();
for (const action of respNonterminalActions) {
if (isInjectJsAction(action)) {
Expand All @@ -232,24 +244,40 @@ export async function applyActions(
once.add("injectjs");
context.log("debug", "respNonterminal action: injectjs");
context.log_performance_debug("[func] injectJS - start");
resp = context.injectRecaptchaJs(await resp);
modifiedResp = await context.injectRecaptchaJs(resp);
// If 'debug' is enabled, await the response to get reasonable performance metrics.
if(context.config.debug) {
resp = Promise.resolve(await resp);
if (context.config.debug) {
modifiedResp = await Promise.resolve(resp);
}
context.log_performance_debug("[func] injectJS - end");
} else {
throw new Error("Unsupported post-response action: " + action);
}
}
return modifiedResp;
}

return resp;
/**
* Apply actions to a request.
*/
export async function applyActions(
context: RecaptchaContext,
req: EdgeRequest,
actions: action.Action[],
): Promise<EdgeResponse> {
const response = await applyPreRequestActions(context, req, actions);
if (response !== null) {
return response;
}
let resp = await context.fetch_origin(req);
return applyPostResponseActions(context, resp, actions);
}

/**
* Process reCAPTCHA request.
*
* Fetches a list of the applicable actions, given a request.
*/
export async function processRequest(context: RecaptchaContext, req: EdgeRequest): Promise<EdgeResponse> {
export async function fetchActions(context: RecaptchaContext, req: EdgeRequest): Promise<action.Action[]> {
let actions: action.Action[] = [];
try {
const localAssessment = await localPolicyAssessment(context, req);
Expand Down Expand Up @@ -279,7 +307,14 @@ export async function processRequest(context: RecaptchaContext, req: EdgeRequest
}
}
}
return actions;
}

/**
* Process reCAPTCHA request.
*/
export async function processRequest(context: RecaptchaContext, req: EdgeRequest): Promise<EdgeResponse> {
const actions = await fetchActions(context, req);
context.log_performance_debug("[func] applyActions - start");
let resp = applyActions(context, req, actions);
context.log_performance_debug("[func] applyActions - end");
Expand Down
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