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app/vmauth: add ability to drop the specified number of /-delimited prefix parts from request path

Browse Source 
This can be done via `drop_src_path_prefix_parts` option at `url_map` and `user` levels.

See https://docs.victoriametrics.com/vmauth.html#dropping-request-path-prefix
This commit is contained in:
Aliaksandr Valialkin 2023-11-13 22:30:39 +01:00
parent 0feaeca3c1
commit 8eed04b2c6
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8 changed files with 219 additions and 51 deletions
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32
app/vmauth/README.md
View File

@ -32,6 +32,38 @@ Pass `-help` to `vmauth` in order to see all the supported command-line flags wi
Feel free [contacting us](mailto:info@victoriametrics.com) if you need customized auth proxy for VictoriaMetrics with the support of LDAP, SSO, RBAC, SAML,
accounting and rate limiting such as [vmgateway](https://docs.victoriametrics.com/vmgateway.html).
## Dropping request path prefix
By default `vmauth` doesn't drop the path prefix from the original request when proxying the request to the matching backend.
Sometimes it is needed to drop path prefix before routing the request to the backend. This can be done by specifying the number of `/`-delimited
prefix parts to drop from the request path via `drop_src_path_prefix_parts` option at `url_map` level or at `user` level.
For example, if you need to serve requests to [vmalert](https://docs.victoriametrics.com/vmalert.html) at `/vmalert/` path prefix,
while serving requests to [vmagent](https://docs.victoriametrics.com/vmagent.html) at `/vmagent/` path prefix for a particular user,
then the following [-auth.config](#auth-config) can be used:
```yml
users:
- username: foo
url_map:
# proxy all the requests, which start with `/vmagent/`, to vmagent backend
- src_paths:
- "/vmagent/.+"
# drop /vmagent/ path prefix from the original request before proxying it to url_prefix.
drop_src_path_prefix_parts: 1
url_prefix: "http://vmagent-backend:8429/"
# proxy all the requests, which start with `/vmalert`, to vmalert backend
- src_paths:
- "/vmalert/.+"
# drop /vmalert/ path prefix from the original request before proxying it to url_prefix.
drop_src_path_prefix_parts: 1
url_prefix: "http://vmalert-backend:8880/"
```
## Load balancing
Each `url_prefix` in the [-auth.config](#auth-config) may contain either a single url or a list of urls.

34
app/vmauth/auth_config.go
View File

@ -40,18 +40,19 @@ type AuthConfig struct {
// UserInfo is user information read from authConfigPath
type UserInfo struct {
Name string `yaml:"name,omitempty"`
BearerToken string `yaml:"bearer_token,omitempty"`
Username string `yaml:"username,omitempty"`
Password string `yaml:"password,omitempty"`
URLPrefix *URLPrefix `yaml:"url_prefix,omitempty"`
URLMaps []URLMap `yaml:"url_map,omitempty"`
HeadersConf HeadersConf `yaml:",inline"`
MaxConcurrentRequests int `yaml:"max_concurrent_requests,omitempty"`
DefaultURL *URLPrefix `yaml:"default_url,omitempty"`
RetryStatusCodes []int `yaml:"retry_status_codes,omitempty"`
TLSInsecureSkipVerify *bool `yaml:"tls_insecure_skip_verify,omitempty"`
TLSCAFile string `yaml:"tls_ca_file,omitempty"`
Name string `yaml:"name,omitempty"`
BearerToken string `yaml:"bearer_token,omitempty"`
Username string `yaml:"username,omitempty"`
Password string `yaml:"password,omitempty"`
URLPrefix *URLPrefix `yaml:"url_prefix,omitempty"`
URLMaps []URLMap `yaml:"url_map,omitempty"`
HeadersConf HeadersConf `yaml:",inline"`
MaxConcurrentRequests int `yaml:"max_concurrent_requests,omitempty"`
DefaultURL *URLPrefix `yaml:"default_url,omitempty"`
RetryStatusCodes []int `yaml:"retry_status_codes,omitempty"`
DropSrcPathPrefixParts int `yaml:"drop_src_path_prefix_parts,omitempty"`
TLSInsecureSkipVerify *bool `yaml:"tls_insecure_skip_verify,omitempty"`
TLSCAFile string `yaml:"tls_ca_file,omitempty"`
concurrencyLimitCh chan struct{}
concurrencyLimitReached *metrics.Counter
@ -119,10 +120,11 @@ func (h *Header) MarshalYAML() (interface{}, error) {
// URLMap is a mapping from source paths to target urls.
type URLMap struct {
SrcPaths []*SrcPath `yaml:"src_paths,omitempty"`
URLPrefix *URLPrefix `yaml:"url_prefix,omitempty"`
HeadersConf HeadersConf `yaml:",inline"`
RetryStatusCodes []int `yaml:"retry_status_codes,omitempty"`
SrcPaths []*SrcPath `yaml:"src_paths,omitempty"`
URLPrefix *URLPrefix `yaml:"url_prefix,omitempty"`
HeadersConf HeadersConf `yaml:",inline"`
RetryStatusCodes []int `yaml:"retry_status_codes,omitempty"`
DropSrcPathPrefixParts int `yaml:"drop_src_path_prefix_parts,omitempty"`
}
// SrcPath represents an src path

6
app/vmauth/auth_config_test.go
View File

@ -249,6 +249,8 @@ users:
- http://node1:343/bbb
- http://node2:343/bbb
tls_insecure_skip_verify: false
retry_status_codes: [500, 501]
drop_src_path_prefix_parts: 1
`, map[string]*UserInfo{
getAuthToken("", "foo", "bar"): {
Username: "foo",
@ -257,7 +259,9 @@ users:
"http://node1:343/bbb",
"http://node2:343/bbb",
}),
TLSInsecureSkipVerify: &insecureSkipVerifyFalse,
TLSInsecureSkipVerify: &insecureSkipVerifyFalse,
RetryStatusCodes: []int{500, 501},
DropSrcPathPrefixParts: 1,
},
})

4
app/vmauth/main.go
View File

@ -164,7 +164,7 @@ func processUserRequest(w http.ResponseWriter, r *http.Request, ui *UserInfo) {
func processRequest(w http.ResponseWriter, r *http.Request, ui *UserInfo) {
u := normalizeURL(r.URL)
up, hc, retryStatusCodes := ui.getURLPrefixAndHeaders(u)
up, hc, retryStatusCodes, dropSrcPathPrefixParts := ui.getURLPrefixAndHeaders(u)
isDefault := false
if up == nil {
if ui.DefaultURL == nil {
@ -198,7 +198,7 @@ func processRequest(w http.ResponseWriter, r *http.Request, ui *UserInfo) {
query.Set("request_path", u.Path)
targetURL.RawQuery = query.Encode()
} else { // Update path for regular routes.
targetURL = mergeURLs(targetURL, u)
targetURL = mergeURLs(targetURL, u, dropSrcPathPrefixParts)
}
ok := tryProcessingRequest(w, r, targetURL, hc, retryStatusCodes, ui.httpTransport)
bu.put()

31
app/vmauth/target_url.go
View File

@ -6,12 +6,13 @@ import (
"strings"
)
func mergeURLs(uiURL, requestURI *url.URL) *url.URL {
func mergeURLs(uiURL, requestURI *url.URL, dropSrcPathPrefixParts int) *url.URL {
targetURL := *uiURL
if strings.HasPrefix(requestURI.Path, "/") {
srcPath := dropPrefixParts(requestURI.Path, dropSrcPathPrefixParts)
if strings.HasPrefix(srcPath, "/") {
targetURL.Path = strings.TrimSuffix(targetURL.Path, "/")
}
targetURL.Path += requestURI.Path
targetURL.Path += srcPath
requestParams := requestURI.Query()
// fast path
if len(requestParams) == 0 {
@ -32,18 +33,34 @@ func mergeURLs(uiURL, requestURI *url.URL) *url.URL {
return &targetURL
}
func (ui *UserInfo) getURLPrefixAndHeaders(u *url.URL) (*URLPrefix, HeadersConf, []int) {
func dropPrefixParts(path string, parts int) string {
if parts <= 0 {
return path
}
for parts > 0 {
path = strings.TrimPrefix(path, "/")
n := strings.IndexByte(path, '/')
if n < 0 {
return ""
}
path = path[n:]
parts--
}
return path
}
func (ui *UserInfo) getURLPrefixAndHeaders(u *url.URL) (*URLPrefix, HeadersConf, []int, int) {
for _, e := range ui.URLMaps {
for _, sp := range e.SrcPaths {
if sp.match(u.Path) {
return e.URLPrefix, e.HeadersConf, e.RetryStatusCodes
return e.URLPrefix, e.HeadersConf, e.RetryStatusCodes, e.DropSrcPathPrefixParts
}
}
}
if ui.URLPrefix != nil {
return ui.URLPrefix, ui.HeadersConf, ui.RetryStatusCodes
return ui.URLPrefix, ui.HeadersConf, ui.RetryStatusCodes, ui.DropSrcPathPrefixParts
}
return nil, HeadersConf{}, nil
return nil, HeadersConf{}, nil, 0
}
func normalizeURL(uOrig *url.URL) *url.URL {

130
app/vmauth/target_url_test.go
View File

@ -7,20 +7,91 @@ import (
"testing"
)
func TestDropPrefixParts(t *testing.T) {
f := func(path string, parts int, expectedResult string) {
t.Helper()
result := dropPrefixParts(path, parts)
if result != expectedResult {
t.Fatalf("unexpected result; got %q; want %q", result, expectedResult)
}
}
f("", 0, "")
f("", 1, "")
f("", 10, "")
f("foo", 0, "foo")
f("foo", -1, "foo")
f("foo", 1, "")
f("/foo", 0, "/foo")
f("/foo/bar", 0, "/foo/bar")
f("/foo/bar/baz", 0, "/foo/bar/baz")
f("foo", 0, "foo")
f("foo/bar", 0, "foo/bar")
f("foo/bar/baz", 0, "foo/bar/baz")
f("/foo/", 0, "/foo/")
f("/foo/bar/", 0, "/foo/bar/")
f("/foo/bar/baz/", 0, "/foo/bar/baz/")
f("/foo", 1, "")
f("/foo/bar", 1, "/bar")
f("/foo/bar/baz", 1, "/bar/baz")
f("foo", 1, "")
f("foo/bar", 1, "/bar")
f("foo/bar/baz", 1, "/bar/baz")
f("/foo/", 1, "/")
f("/foo/bar/", 1, "/bar/")
f("/foo/bar/baz/", 1, "/bar/baz/")
f("/foo", 2, "")
f("/foo/bar", 2, "")
f("/foo/bar/baz", 2, "/baz")
f("foo", 2, "")
f("foo/bar", 2, "")
f("foo/bar/baz", 2, "/baz")
f("/foo/", 2, "")
f("/foo/bar/", 2, "/")
f("/foo/bar/baz/", 2, "/baz/")
f("/foo", 3, "")
f("/foo/bar", 3, "")
f("/foo/bar/baz", 3, "")
f("foo", 3, "")
f("foo/bar", 3, "")
f("foo/bar/baz", 3, "")
f("/foo/", 3, "")
f("/foo/bar/", 3, "")
f("/foo/bar/baz/", 3, "/")
f("/foo/", 4, "")
f("/foo/bar/", 4, "")
f("/foo/bar/baz/", 4, "")
}
func TestCreateTargetURLSuccess(t *testing.T) {
f := func(ui *UserInfo, requestURI, expectedTarget, expectedRequestHeaders, expectedResponseHeaders string, expectedRetryStatusCodes []int) {
f := func(ui *UserInfo, requestURI, expectedTarget, expectedRequestHeaders, expectedResponseHeaders string,
expectedRetryStatusCodes []int, expectedDropSrcPathPrefixParts int) {
t.Helper()
u, err := url.Parse(requestURI)
if err != nil {
t.Fatalf("cannot parse %q: %s", requestURI, err)
}
u = normalizeURL(u)
up, hc, retryStatusCodes := ui.getURLPrefixAndHeaders(u)
up, hc, retryStatusCodes, dropSrcPathPrefixParts := ui.getURLPrefixAndHeaders(u)
if up == nil {
t.Fatalf("cannot determie backend: %s", err)
}
bu := up.getLeastLoadedBackendURL()
target := mergeURLs(bu.url, u)
target := mergeURLs(bu.url, u, dropSrcPathPrefixParts)
bu.put()
if target.String() != expectedTarget {
t.Fatalf("unexpected target; got %q; want %q", target, expectedTarget)
@ -32,11 +103,14 @@ func TestCreateTargetURLSuccess(t *testing.T) {
if !reflect.DeepEqual(retryStatusCodes, expectedRetryStatusCodes) {
t.Fatalf("unexpected retryStatusCodes; got %d; want %d", retryStatusCodes, expectedRetryStatusCodes)
}
if dropSrcPathPrefixParts != expectedDropSrcPathPrefixParts {
t.Fatalf("unexpected dropSrcPathPrefixParts; got %d; want %d", dropSrcPathPrefixParts, expectedDropSrcPathPrefixParts)
}
}
// Simple routing with `url_prefix`
f(&UserInfo{
URLPrefix: mustParseURL("http://foo.bar"),
}, "", "http://foo.bar/.", "[]", "[]", nil)
}, "", "http://foo.bar/.", "[]", "[]", nil, 0)
f(&UserInfo{
URLPrefix: mustParseURL("http://foo.bar"),
HeadersConf: HeadersConf{
@ -45,29 +119,30 @@ func TestCreateTargetURLSuccess(t *testing.T) {
Value: "aaa",
}},
},
RetryStatusCodes: []int{503, 501},
}, "/", "http://foo.bar", `[{"bb" "aaa"}]`, `[]`, []int{503, 501})
RetryStatusCodes: []int{503, 501},
DropSrcPathPrefixParts: 2,
}, "/a/b/c", "http://foo.bar/c", `[{"bb" "aaa"}]`, `[]`, []int{503, 501}, 2)
f(&UserInfo{
URLPrefix: mustParseURL("http://foo.bar/federate"),
}, "/", "http://foo.bar/federate", "[]", "[]", nil)
}, "/", "http://foo.bar/federate", "[]", "[]", nil, 0)
f(&UserInfo{
URLPrefix: mustParseURL("http://foo.bar"),
}, "a/b?c=d", "http://foo.bar/a/b?c=d", "[]", "[]", nil)
}, "a/b?c=d", "http://foo.bar/a/b?c=d", "[]", "[]", nil, 0)
f(&UserInfo{
URLPrefix: mustParseURL("https://sss:3894/x/y"),
}, "/z", "https://sss:3894/x/y/z", "[]", "[]", nil)
}, "/z", "https://sss:3894/x/y/z", "[]", "[]", nil, 0)
f(&UserInfo{
URLPrefix: mustParseURL("https://sss:3894/x/y"),
}, "/../../aaa", "https://sss:3894/x/y/aaa", "[]", "[]", nil)
}, "/../../aaa", "https://sss:3894/x/y/aaa", "[]", "[]", nil, 0)
f(&UserInfo{
URLPrefix: mustParseURL("https://sss:3894/x/y"),
}, "/./asd/../../aaa?a=d&s=s/../d", "https://sss:3894/x/y/aaa?a=d&s=s%2F..%2Fd", "[]", "[]", nil)
}, "/./asd/../../aaa?a=d&s=s/../d", "https://sss:3894/x/y/aaa?a=d&s=s%2F..%2Fd", "[]", "[]", nil, 0)
// Complex routing with `url_map`
ui := &UserInfo{
URLMaps: []URLMap{
{
SrcPaths: getSrcPaths([]string{"/api/v1/query"}),
SrcPaths: getSrcPaths([]string{"/vmsingle/api/v1/query"}),
URLPrefix: mustParseURL("http://vmselect/0/prometheus"),
HeadersConf: HeadersConf{
RequestHeaders: []Header{
@ -87,7 +162,8 @@ func TestCreateTargetURLSuccess(t *testing.T) {
},
},
},
RetryStatusCodes: []int{503, 500, 501},
RetryStatusCodes: []int{503, 500, 501},
DropSrcPathPrefixParts: 1,
},
{
SrcPaths: getSrcPaths([]string{"/api/v1/write"}),
@ -105,11 +181,12 @@ func TestCreateTargetURLSuccess(t *testing.T) {
Value: "y",
}},
},
RetryStatusCodes: []int{502},
RetryStatusCodes: []int{502},
DropSrcPathPrefixParts: 2,
}
f(ui, "/api/v1/query?query=up", "http://vmselect/0/prometheus/api/v1/query?query=up", `[{"xx" "aa"} {"yy" "asdf"}]`, `[{"qwe" "rty"}]`, []int{503, 500, 501})
f(ui, "/api/v1/write", "http://vminsert/0/prometheus/api/v1/write", "[]", "[]", nil)
f(ui, "/api/v1/query_range", "http://default-server/api/v1/query_range", `[{"bb" "aaa"}]`, `[{"x" "y"}]`, []int{502})
f(ui, "/vmsingle/api/v1/query?query=up", "http://vmselect/0/prometheus/api/v1/query?query=up", `[{"xx" "aa"} {"yy" "asdf"}]`, `[{"qwe" "rty"}]`, []int{503, 500, 501}, 1)
f(ui, "/api/v1/write", "http://vminsert/0/prometheus/api/v1/write", "[]", "[]", nil, 0)
f(ui, "/foo/bar/api/v1/query_range", "http://default-server/api/v1/query_range", `[{"bb" "aaa"}]`, `[{"x" "y"}]`, []int{502}, 2)
// Complex routing regexp paths in `url_map`
ui = &UserInfo{
@ -125,17 +202,17 @@ func TestCreateTargetURLSuccess(t *testing.T) {
},
URLPrefix: mustParseURL("http://default-server"),
}
f(ui, "/api/v1/query?query=up", "http://vmselect/0/prometheus/api/v1/query?query=up", "[]", "[]", nil)
f(ui, "/api/v1/query_range?query=up", "http://vmselect/0/prometheus/api/v1/query_range?query=up", "[]", "[]", nil)
f(ui, "/api/v1/label/foo/values", "http://vmselect/0/prometheus/api/v1/label/foo/values", "[]", "[]", nil)
f(ui, "/api/v1/write", "http://vminsert/0/prometheus/api/v1/write", "[]", "[]", nil)
f(ui, "/api/v1/foo/bar", "http://default-server/api/v1/foo/bar", "[]", "[]", nil)
f(ui, "/api/v1/query?query=up", "http://vmselect/0/prometheus/api/v1/query?query=up", "[]", "[]", nil, 0)
f(ui, "/api/v1/query_range?query=up", "http://vmselect/0/prometheus/api/v1/query_range?query=up", "[]", "[]", nil, 0)
f(ui, "/api/v1/label/foo/values", "http://vmselect/0/prometheus/api/v1/label/foo/values", "[]", "[]", nil, 0)
f(ui, "/api/v1/write", "http://vminsert/0/prometheus/api/v1/write", "[]", "[]", nil, 0)
f(ui, "/api/v1/foo/bar", "http://default-server/api/v1/foo/bar", "[]", "[]", nil, 0)
f(&UserInfo{
URLPrefix: mustParseURL("http://foo.bar?extra_label=team=dev"),
}, "/api/v1/query", "http://foo.bar/api/v1/query?extra_label=team=dev", "[]", "[]", nil)
}, "/api/v1/query", "http://foo.bar/api/v1/query?extra_label=team=dev", "[]", "[]", nil, 0)
f(&UserInfo{
URLPrefix: mustParseURL("http://foo.bar?extra_label=team=mobile"),
}, "/api/v1/query?extra_label=team=dev", "http://foo.bar/api/v1/query?extra_label=team%3Dmobile", "[]", "[]", nil)
}, "/api/v1/query?extra_label=team=dev", "http://foo.bar/api/v1/query?extra_label=team%3Dmobile", "[]", "[]", nil, 0)
}
func TestCreateTargetURLFailure(t *testing.T) {
@ -146,7 +223,7 @@ func TestCreateTargetURLFailure(t *testing.T) {
t.Fatalf("cannot parse %q: %s", requestURI, err)
}
u = normalizeURL(u)
up, hc, retryStatusCodes := ui.getURLPrefixAndHeaders(u)
up, hc, retryStatusCodes, dropSrcPathPrefixParts := ui.getURLPrefixAndHeaders(u)
if up != nil {
t.Fatalf("unexpected non-empty up=%#v", up)
}
@ -159,6 +236,9 @@ func TestCreateTargetURLFailure(t *testing.T) {
if retryStatusCodes != nil {
t.Fatalf("unexpected non-empty retryStatusCodes=%d", retryStatusCodes)
}
if dropSrcPathPrefixParts != 0 {
t.Fatalf("unexpected non-zero dropSrcPathPrefixParts=%d", dropSrcPathPrefixParts)
}
}
f(&UserInfo{}, "/foo/bar")
f(&UserInfo{

1
docs/CHANGELOG.md
View File

@ -79,6 +79,7 @@ The sandbox cluster installation is running under the constant load generated by
* FEATURE: [vmalert-tool](https://docs.victoriametrics.com/#vmalert-tool): add `unittest` command to run unittest for alerting and recording rules. See [this pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/4789) for details.
* FEATURE: dashboards/vmalert: add new panel `Missed evaluations` for indicating alerting groups that miss their evaluations.
* FEATURE: all: track requests with wrong auth key and wrong basic auth at `vm_http_request_errors_total` [metric](https://docs.victoriametrics.com/#monitoring) with `reason="wrong_auth_key"` and `reason="wrong_basic_auth"`. See [this issue](https://github.com/victoriaMetrics/victoriaMetrics/issues/4590). Thanks to @venkatbvc for the [pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5166).
* FEATURE: [vmauth](https://docs.victoriametrics.com/vmauth.html): add ability to drop the specified number of `/`-delimited prefix parts from the request path before proxying the request to the matching backend. See [these docs](https://docs.victoriametrics.com/vmauth.html#dropping-request-path-prefix).
* FEATURE: [vmauth](https://docs.victoriametrics.com/vmauth.html): add ability to skip TLS verification and to specify TLS Root CA when connecting to backends. See [these docs](https://docs.victoriametrics.com/vmauth.html#backend-tls-setup) and [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5240).
* FEATURE: `vmstorage`: add `-blockcache.missesBeforeCaching` command-line flag, which can be used for fine-tuning RAM usage for `indexdb/dataBlocks` cache when queries touching big number of time series are executed.
* FEATURE: add `-loggerMaxArgLen` command-line flag for fine-tuning the maximum lengths of logged args.

32
docs/vmauth.md
View File

@ -43,6 +43,38 @@ Pass `-help` to `vmauth` in order to see all the supported command-line flags wi
Feel free [contacting us](mailto:info@victoriametrics.com) if you need customized auth proxy for VictoriaMetrics with the support of LDAP, SSO, RBAC, SAML,
accounting and rate limiting such as [vmgateway](https://docs.victoriametrics.com/vmgateway.html).
## Dropping request path prefix
By default `vmauth` doesn't drop the path prefix from the original request when proxying the request to the matching backend.
Sometimes it is needed to drop path prefix before routing the request to the backend. This can be done by specifying the number of `/`-delimited
prefix parts to drop from the request path via `drop_src_path_prefix_parts` option at `url_map` level or at `user` level.
For example, if you need to serve requests to [vmalert](https://docs.victoriametrics.com/vmalert.html) at `/vmalert/` path prefix,
while serving requests to [vmagent](https://docs.victoriametrics.com/vmagent.html) at `/vmagent/` path prefix for a particular user,
then the following [-auth.config](#auth-config) can be used:
```yml
users:
- username: foo
url_map:
# proxy all the requests, which start with `/vmagent/`, to vmagent backend
- src_paths:
- "/vmagent/.+"
# drop /vmagent/ path prefix from the original request before proxying it to url_prefix.
drop_src_path_prefix_parts: 1
url_prefix: "http://vmagent-backend:8429/"
# proxy all the requests, which start with `/vmalert`, to vmalert backend
- src_paths:
- "/vmalert/.+"
# drop /vmalert/ path prefix from the original request before proxying it to url_prefix.
drop_src_path_prefix_parts: 1
url_prefix: "http://vmalert-backend:8880/"
```
## Load balancing
Each `url_prefix` in the [-auth.config](#auth-config) may contain either a single url or a list of urls.