Skip to content

Handle store backend errors #325

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 4 commits into from
Jul 19, 2021
Merged

Handle store backend errors #325

Show file tree
Hide file tree
Changes from 3 commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
c6f7cea
Handle backend errors
dtaniwaki Jun 24, 2021
6895357
Fix lint issues
dtaniwaki Jun 24, 2021
60c3e60
Remove unnecessary catch
dtaniwaki Jun 24, 2021
61c1278
use async def for targetForReq
minrk Jul 19, 2021
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
151 changes: 80 additions & 71 deletions lib/configproxy.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -379,19 +379,23 @@ class ConfigurableProxy extends EventEmitter {
}

targetForReq(req) {
var metricsTimerEnd = this.metrics.findTargetForReqSummary.startTimer();
// return proxy target for a given url path
var basePath = this.hostRouting ? "/" + parseHost(req) : "";
var path = basePath + decodeURIComponent(URL.parse(req.url).pathname);

return this._routes.getTarget(path).then(function (route) {
metricsTimerEnd();
if (route) {
return {
prefix: route.prefix,
target: route.data.target,
};
}
return new Promise((resolve, reject) => {
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Noting for review:

wrapping this in a promise ensures that targetForReq always returns a Promise, even if routes.getTarget raises directly (as opposed to returning a failing promise).

var metricsTimerEnd = this.metrics.findTargetForReqSummary.startTimer();
// return proxy target for a given url path
var basePath = this.hostRouting ? "/" + parseHost(req) : "";
var path = basePath + decodeURIComponent(URL.parse(req.url).pathname);

resolve(
this._routes.getTarget(path).then(function (route) {
metricsTimerEnd();
if (route) {
return {
prefix: route.prefix,
target: route.data.target,
};
}
})
);
});
}

Expand Down Expand Up @@ -528,72 +532,77 @@ class ConfigurableProxy extends EventEmitter {
var args = Array.prototype.slice.call(arguments, 1);

// get the proxy target
return this.targetForReq(req).then((match) => {
if (!match) {
that.handleProxyError(404, kind, req, res);
return;
}

if (kind === "web") {
that.emit("proxyRequest", req, res);
} else {
that.emit("proxyRequestWs", req, res, args[2]);
}
var prefix = match.prefix;
var target = match.target;
that.log.debug("PROXY %s %s to %s", kind.toUpperCase(), _logUrl(req.url), target);
if (!that.includePrefix) {
req.url = req.url.slice(prefix.length);
}
return this.targetForReq(req)
.then((match) => {
if (!match) {
that.handleProxyError(404, kind, req, res);
return;
}

target = URL.parse(target);
if (that.options.clientSsl) {
target.key = that.options.clientSsl.key;
target.cert = that.options.clientSsl.cert;
target.ca = that.options.clientSsl.ca;
}
if (kind === "web") {
that.emit("proxyRequest", req, res);
} else {
that.emit("proxyRequestWs", req, res, args[2]);
}
var prefix = match.prefix;
var target = match.target;
that.log.debug("PROXY %s %s to %s", kind.toUpperCase(), _logUrl(req.url), target);
if (!that.includePrefix) {
req.url = req.url.slice(prefix.length);
}

// add config argument
args.push({ target: target });
target = URL.parse(target);
if (that.options.clientSsl) {
target.key = that.options.clientSsl.key;
target.cert = that.options.clientSsl.cert;
target.ca = that.options.clientSsl.ca;
}

// add error handling
args.push(function (e) {
that.handleProxyError(503, kind, req, res, e);
});
// add config argument
args.push({ target: target });

// dispatch the actual method, either:
// - proxy.web(req, res, options, errorHandler)
// - proxy.ws(req, socket, head, options, errorHandler)
that.proxy[kind].apply(that.proxy, args);
// add error handling
args.push(function (e) {
that.handleProxyError(503, kind, req, res, e);
});

// update timestamp on any request/reply data as well (this includes websocket data)
req.on("data", function () {
that.updateLastActivity(prefix);
});
// dispatch the actual method, either:
// - proxy.web(req, res, options, errorHandler)
// - proxy.ws(req, socket, head, options, errorHandler)
that.proxy[kind].apply(that.proxy, args);

res.on("data", function () {
that.updateLastActivity(prefix);
});
// update timestamp on any request/reply data as well (this includes websocket data)
req.on("data", function () {
that.updateLastActivity(prefix);
});

if (kind === "web") {
// update last activity on completion of the request
// only consider 'successful' requests activity
// A flood of invalid requests such as 404s or 403s
// or 503s because the endpoint is down
// shouldn't make it look like the endpoint is 'active'

// we no longer register activity at the *start* of the request
// because at that point we don't know if the endpoint is even available
res.on("finish", function () {
// (don't count redirects...but should we?)
if (res.statusCode < 300) {
that.updateLastActivity(prefix);
} else {
that.log.debug("Not recording activity for status %s on %s", res.statusCode, prefix);
}
res.on("data", function () {
that.updateLastActivity(prefix);
});
}
});

if (kind === "web") {
// update last activity on completion of the request
// only consider 'successful' requests activity
// A flood of invalid requests such as 404s or 403s
// or 503s because the endpoint is down
// shouldn't make it look like the endpoint is 'active'

// we no longer register activity at the *start* of the request
// because at that point we don't know if the endpoint is even available
res.on("finish", function () {
// (don't count redirects...but should we?)
if (res.statusCode < 300) {
that.updateLastActivity(prefix);
} else {
that.log.debug("Not recording activity for status %s on %s", res.statusCode, prefix);
}
});
}
})
.catch(function (e) {
if (res.finished) throw e;
that.handleProxyError(500, kind, req, res, e);
});
Comment on lines +596 to +599
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

These lines are the only changes in this function: adding the catch. prettier chooses a different indentation when there's both a .then and a .catch, which makes this PR look bigger than it is.

}

handleProxyWs(req, socket, head) {
Expand Down
14 changes: 14 additions & 0 deletions test/proxy_spec.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -379,6 +379,20 @@ describe("Proxy Tests", function () {
.then(done);
});

it("backend error", function (done) {
var proxyPort = 55550;
util
.setupProxy(proxyPort, { errorTarget: "http://127.0.0.1:55565" }, [])
.then(() => r("http://127.0.0.1:" + proxyPort + "/%"))
.then((body) => done.fail("Expected 500"))
.catch((err) => {
expect(err.statusCode).toEqual(500);
expect(err.response.headers["content-type"]).toEqual("text/plain");
expect(err.response.body).toEqual("/%");
})
.then(done);
});

it("Redirect location untouched without rewrite options", function (done) {
var redirectTo = "http://foo.com:12345/whatever";
util
Expand Down