ContainerImage.Pinniped/internal/starformer/starformer_test.go

361 lines
11 KiB
Go

// Copyright 2021 the Pinniped contributors. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0
package starformer
import (
"fmt"
"testing"
"time"
"github.com/stretchr/testify/require"
"go.pinniped.dev/internal/here"
)
func TestTypicalPerformance(t *testing.T) {
t.Parallel()
starformer, err := New(here.Doc(`
def transform(username, groups):
prefixedGroups = []
for g in groups:
prefixedGroups.append("group_prefix:" + g)
return "username_prefix:" + username, prefixedGroups
`))
require.NoError(t, err)
require.NotNil(t, starformer)
groups := []string{}
wantGroups := []string{}
for i := 0; i < 100; i++ {
groups = append(groups, fmt.Sprintf("g%d", i))
wantGroups = append(wantGroups, fmt.Sprintf("group_prefix:g%d", i))
}
// Before looking at performance, check that the behavior of the function is correct.
gotUsername, gotGroups, err := starformer.Transform("ryan", groups)
require.NoError(t, err)
require.Equal(t, "username_prefix:ryan", gotUsername)
require.Equal(t, wantGroups, gotGroups)
// Calling it a second time should give the same results again for the same inputs.
gotUsername, gotGroups, err = starformer.Transform("ryan", groups)
require.NoError(t, err)
require.Equal(t, "username_prefix:ryan", gotUsername)
require.Equal(t, wantGroups, gotGroups)
// This is meant to give a sense of typical runtime of a Starlark function which transforms
// a username and 100 group names. It is not meant to be a pass/fail test or scientific benchmark test.
iterations := 1000
start := time.Now()
for i := 0; i < iterations; i++ {
_, _, _ = starformer.Transform("ryan", groups)
}
elapsed := time.Since(start)
t.Logf("TestTypicalPerformance %d iteration of Transform took %s; average runtime %s", iterations, elapsed, elapsed/time.Duration(iterations))
// On my laptop this prints: TestTypicalPerformance 1000 iteration of Transform took 299.109387ms; average runtime 299.109µs
}
func TestTransformer(t *testing.T) {
// See Starlark dialect language documentation here: https://github.com/google/starlark-go/blob/master/doc/spec.md
tests := []struct {
name string
starlarkSrc string
username string
groups []string
wantUsername string
wantGroups []string
wantNewErr string
wantTransformErr string
}{
{
name: "identity function makes no modification",
starlarkSrc: here.Doc(`
def transform(username, groups):
return username, groups
`),
username: "ryan",
groups: []string{"g1", "g2"},
wantUsername: "ryan",
wantGroups: []string{"g1", "g2"},
},
{
name: "returning None is a shortcut for making no modification",
starlarkSrc: here.Doc(`
def transform(username, groups):
return None
`),
username: "ryan",
groups: []string{"g1", "g2"},
wantUsername: "ryan",
wantGroups: []string{"g1", "g2"},
},
{
name: "prefixing the username",
starlarkSrc: here.Doc(`
def transform(username, groups):
return "foobar:" + username, groups
`),
username: "ryan",
groups: []string{"g1", "g2"},
wantUsername: "foobar:ryan",
wantGroups: []string{"g1", "g2"},
},
{
name: "down-casing the username",
starlarkSrc: here.Doc(`
def transform(username, groups):
return username.lower(), groups
`),
username: "RyAn",
groups: []string{"g1", "g2"},
wantUsername: "ryan",
wantGroups: []string{"g1", "g2"},
},
{
name: "removing all groups",
starlarkSrc: here.Doc(`
def transform(username, groups):
return username, ()
`),
username: "ryan",
groups: []string{"g1", "g2"},
wantUsername: "ryan",
wantGroups: []string{},
},
{
name: "modifying groups",
starlarkSrc: here.Doc(`
def transform(username, groups):
return username, ("new-g1", "new-g2")
`),
username: "ryan",
groups: []string{"g1", "g2"},
wantUsername: "ryan",
wantGroups: []string{"new-g1", "new-g2"},
},
{
name: "converting the groups param to a list type in the business logic is easy, and returning groups as a list works",
starlarkSrc: here.Doc(`
def transform(username, groups):
groupsList = list(groups)
groupsList.pop()
return username, groupsList
`),
username: "ryan",
groups: []string{"g1", "g3"},
wantUsername: "ryan",
wantGroups: []string{"g1"},
},
{
name: "can print from the script",
starlarkSrc: here.Doc(`
print("this should get logged by Pinniped but it is not asserted here")
def transform(username, groups):
print("this should get logged by Pinniped but it is not asserted here:", username)
return username, groups
`),
username: "ryan",
groups: []string{"g1", "g2"},
wantUsername: "ryan",
wantGroups: []string{"g1", "g2"},
},
{
name: "rejecting a login by raising an error",
starlarkSrc: here.Doc(`
def transform(username, groups):
if username == "ryan":
fail("i don't like the username", username)
else:
return username, groups
`),
username: "ryan",
groups: []string{"g1", "g2"},
wantTransformErr: `error while running starlark "transform" function: fail: i don't like the username ryan`,
},
{
name: "using the non-standard 'set' type is allowed",
starlarkSrc: here.Doc(`
def transform(username, groups):
groupsSet = set(groups)
if "g2" in groupsSet:
return username, groups
else:
fail("user", username, "does not belong to group g2")
`),
username: "ryan",
groups: []string{"g1", "g3"},
wantTransformErr: `error while running starlark "transform" function: fail: user ryan does not belong to group g2`,
},
{
name: "using the non-standard 'set' type is allowed, and the groups can be returned as a set",
starlarkSrc: here.Doc(`
def transform(username, groups):
groupsSet = set(groups)
groupsSet = groupsSet.union(["g42"])
if "g2" in groupsSet:
return username, groupsSet
else:
fail("user", username, "does not belong to group g2")
`),
username: "ryan",
groups: []string{"g1", "g2"},
wantUsername: "ryan",
wantGroups: []string{"g1", "g2", "g42"},
},
{
name: "the math module may be loaded",
starlarkSrc: here.Doc(`
load('math.star', 'math')
def transform(username, groups):
if math.round(0.4) == 0.0:
return username, groups
else:
fail("math module is supposed to work")
`),
username: "ryan",
groups: []string{"g1", "g2"},
wantUsername: "ryan",
wantGroups: []string{"g1", "g2"},
},
{
name: "the json module may be loaded",
starlarkSrc: here.Doc(`
load('json.star', 'json')
def transform(username, groups):
return username, [json.encode({"hello": groups[0]})]
`),
username: "ryan",
groups: []string{"g1", "g2"},
wantUsername: "ryan",
wantGroups: []string{`{"hello":"g1"}`},
},
{
name: "the time module may be loaded",
starlarkSrc: here.Doc(`
load('time.star', 'time')
def transform(username, groups):
if time.now() > time.parse_time("2001-01-20T00:00:00Z"):
return "someone", ["g3", "g4"]
fail("huh?")
`),
username: "ryan",
groups: []string{"g1", "g2"},
wantUsername: "someone",
wantGroups: []string{"g3", "g4"},
},
{
name: "loading other modules results in an error",
starlarkSrc: here.Doc(`
load('other.star', 'other')
def transform(username, groups):
return username, groups
`),
username: "ryan",
groups: []string{"g1", "g2"},
wantNewErr: "error while loading starlark transform script: cannot load other.star: only the following modules may be loaded: json.star, time.star, math.star",
},
{
name: "unexpected error during loading",
starlarkSrc: here.Doc(`
this is not valid starlark syntax
`),
wantNewErr: "error while loading starlark transform script: transform.star:1:8: got illegal token, want newline",
},
{
name: "too many execution steps during loading",
starlarkSrc: here.Doc(`
def helper():
a = 0
for x in range(1000000):
a += 1
helper()
`),
wantNewErr: "error while loading starlark transform script: Starlark computation cancelled: too many steps",
},
{
name: "too many execution steps during transform function",
starlarkSrc: here.Doc(`
def transform(username, groups):
a = 0
for x in range(1000000):
a += 1
return username, groups
`),
username: "ryan",
groups: []string{"g1", "g2"},
wantTransformErr: `error while running starlark "transform" function: Starlark computation cancelled: too many steps`,
},
{
name: "returning the wrong data type",
starlarkSrc: here.Doc(`
def transform(username, groups):
return 42
`),
username: "ryan",
groups: []string{"g1", "g2"},
wantTransformErr: `expected starlark "transform" function to return None or a Tuple of length 2`,
},
{
name: "returning the wrong data type inside the groups iterable return value",
starlarkSrc: here.Doc(`
def transform(username, groups):
return username, ("g1", 42)
`),
username: "ryan",
groups: []string{"g1", "g2"},
wantTransformErr: `expected starlark "transform" function's return tuple's second value to contain only non-empty strings`,
},
{
name: "returning an empty string inside the groups iterable return value",
starlarkSrc: here.Doc(`
def transform(username, groups):
return username, ("g1", "", "g2")
`),
username: "ryan",
groups: []string{"g1", "g2"},
wantTransformErr: `expected starlark "transform" function's return tuple's second value to contain only non-empty strings`,
},
{
name: "no transform function defined",
starlarkSrc: here.Doc(`
def otherFunction(username, groups):
return None
`),
wantNewErr: `starlark script does not define "transform" function`,
},
{
name: "transform function defined with wrong number of positional parameters",
starlarkSrc: here.Doc(`
def transform(username):
return None
`),
wantNewErr: `starlark script's global "transform" function has 1 parameters but should have 2`,
},
}
for _, tt := range tests {
tt := tt
t.Run(tt.name, func(t *testing.T) {
t.Parallel()
starformer, err := New(tt.starlarkSrc)
if tt.wantNewErr != "" {
require.EqualError(t, err, tt.wantNewErr)
require.Nil(t, starformer)
return // wanted an error from New, so don't keep going
}
require.NoError(t, err)
require.NotNil(t, starformer)
gotUsername, gotGroups, err := starformer.Transform(tt.username, tt.groups)
if tt.wantTransformErr != "" {
require.EqualError(t, err, tt.wantTransformErr)
} else {
require.NoError(t, err)
}
require.Equal(t, tt.wantUsername, gotUsername)
require.Equal(t, tt.wantGroups, gotGroups)
})
}
}