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package
v0.30.0-alpha.2 Latest Latest
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 Go to latest Published: Feb 14, 2024 License: Apache-2.0 Imports: 25 Imported by: 10

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Index

Constants

This section is empty.

Variables

View Source 
var (
	AuthorizerType    = cel.ObjectType("kubernetes.authorization.Authorizer")
	PathCheckType     = cel.ObjectType("kubernetes.authorization.PathCheck")
	GroupCheckType    = cel.ObjectType("kubernetes.authorization.GroupCheck")
	ResourceCheckType = cel.ObjectType("kubernetes.authorization.ResourceCheck")
	DecisionType      = cel.ObjectType("kubernetes.authorization.Decision")
)
View Source 
var FindAllRegexOptimization = &interpreter.RegexOptimization{
	Function:   "findAll",
	RegexIndex: 1,
	Factory: func(call interpreter.InterpretableCall, regexPattern string) (interpreter.InterpretableCall, error) {
		compiledRegex, err := regexp.Compile(regexPattern)
		if err != nil {
			return nil, err
		}
		return interpreter.NewCall(call.ID(), call.Function(), call.OverloadID(), call.Args(), func(args ...ref.Val) ref.Val {
			argn := len(args)
			if argn < 2 || argn > 3 {
				return types.NoSuchOverloadErr()
			}
			str, ok := args[0].Value().(string)
			if !ok {
				return types.MaybeNoSuchOverloadErr(args[0])
			}
			n := int64(-1)
			if argn == 3 {
				n, ok = args[2].Value().(int64)
				if !ok {
					return types.MaybeNoSuchOverloadErr(args[2])
				}
			}

			result := compiledRegex.FindAllString(str, int(n))
			return types.NewStringList(types.DefaultTypeAdapter, result)
		}), nil
	},
}

FindAllRegexOptimization optimizes the 'findAll' function by compiling the regex pattern and reporting any compilation errors at program creation time, and using the compiled regex pattern for all function call invocations.

View Source 
var FindRegexOptimization = &interpreter.RegexOptimization{
	Function:   "find",
	RegexIndex: 1,
	Factory: func(call interpreter.InterpretableCall, regexPattern string) (interpreter.InterpretableCall, error) {
		compiledRegex, err := regexp.Compile(regexPattern)
		if err != nil {
			return nil, err
		}
		return interpreter.NewCall(call.ID(), call.Function(), call.OverloadID(), call.Args(), func(args ...ref.Val) ref.Val {
			if len(args) != 2 {
				return types.NoSuchOverloadErr()
			}
			in, ok := args[0].Value().(string)
			if !ok {
				return types.MaybeNoSuchOverloadErr(args[0])
			}
			return types.String(compiledRegex.FindString(in))
		}), nil
	},
}

FindRegexOptimization optimizes the 'find' function by compiling the regex pattern and reporting any compilation errors at program creation time, and using the compiled regex pattern for all function call invocations.

Functions

func Authz added in v0.27.0 

func Authz() cel.EnvOption

Authz provides a CEL function library extension for performing authorization checks. Note that authorization checks are only supported for CEL expression fields in the API where an 'authorizer' variable is provided to the CEL expression. See the documentation of API fields where CEL expressions are used to learn if the 'authorizer' variable is provided.

path

Returns a PathCheck configured to check authorization for a non-resource request path (e.g. /healthz). If path is an empty string, an error is returned. Note that the leading '/' is not required. 

<Authorizer>.path(<string>) <PathCheck>

Examples: 

authorizer.path('/healthz') // returns a PathCheck for the '/healthz' API path
authorizer.path('') // results in "path must not be empty" error
authorizer.path('  ') // results in "path must not be empty" error

group

Returns a GroupCheck configured to check authorization for the API resources for a particular API group. Note that authorization checks are only supported for CEL expression fields in the API where an 'authorizer' variable is provided to the CEL expression. Check the documentation of API fields where CEL expressions are used to learn if the 'authorizer' variable is provided. 

<Authorizer>.group(<string>) <GroupCheck>

Examples: 

authorizer.group('apps') // returns a GroupCheck for the 'apps' API group
authorizer.group('') // returns a GroupCheck for the core API group
authorizer.group('example.com') // returns a GroupCheck for the custom resources in the 'example.com' API group

serviceAccount

Returns an Authorizer configured to check authorization for the provided service account namespace and name. If the name is not a valid DNS subdomain string (as defined by RFC 1123), an error is returned. If the namespace is not a valid DNS label (as defined by RFC 1123), an error is returned. 

<Authorizer>.serviceAccount(<string>, <string>) <Authorizer>

Examples: 

authorizer.serviceAccount('default', 'myserviceaccount') // returns an Authorizer for the service account with namespace 'default' and name 'myserviceaccount'
authorizer.serviceAccount('not@a#valid!namespace', 'validname') // returns an error
authorizer.serviceAccount('valid.example.com', 'invalid@*name') // returns an error

resource

Returns a ResourceCheck configured to check authorization for a particular API resource. Note that the provided resource string should be a lower case plural name of a Kubernetes API resource. 

<GroupCheck>.resource(<string>) <ResourceCheck>

Examples: 

authorizer.group('apps').resource('deployments') // returns a ResourceCheck for the 'deployments' resources in the 'apps' group.
authorizer.group('').resource('pods') // returns a ResourceCheck for the 'pods' resources in the core group.
authorizer.group('apps').resource('') // results in "resource must not be empty" error
authorizer.group('apps').resource('  ') // results in "resource must not be empty" error

subresource

Returns a ResourceCheck configured to check authorization for a particular subresource of an API resource. If subresource is set to "", the subresource field of this ResourceCheck is considered unset. 

<ResourceCheck>.subresource(<string>) <ResourceCheck>

Examples: 

authorizer.group('').resource('pods').subresource('status') // returns a ResourceCheck the 'status' subresource of 'pods'
authorizer.group('apps').resource('deployments').subresource('scale') // returns a ResourceCheck the 'scale' subresource of 'deployments'
authorizer.group('example.com').resource('widgets').subresource('scale') // returns a ResourceCheck for the 'scale' subresource of the 'widgets' custom resource
authorizer.group('example.com').resource('widgets').subresource('') // returns a ResourceCheck for the 'widgets' resource.

namespace

Returns a ResourceCheck configured to check authorization for a particular namespace. For cluster scoped resources, namespace() does not need to be called; namespace defaults to "", which is the correct namespace value to use to check cluster scoped resources. If namespace is set to "", the ResourceCheck will check authorization for the cluster scope. 

<ResourceCheck>.namespace(<string>) <ResourceCheck>

Examples: 

authorizer.group('apps').resource('deployments').namespace('test') // returns a ResourceCheck for 'deployments' in the 'test' namespace
authorizer.group('').resource('pods').namespace('default') // returns a ResourceCheck for 'pods' in the 'default' namespace
authorizer.group('').resource('widgets').namespace('') // returns a ResourceCheck for 'widgets' in the cluster scope

name

Returns a ResourceCheck configured to check authorization for a particular resource name. If name is set to "", the name field of this ResourceCheck is considered unset. 

<ResourceCheck>.name(<name>) <ResourceCheck>

Examples: 

authorizer.group('apps').resource('deployments').namespace('test').name('backend') // returns a ResourceCheck for the 'backend' 'deployments' resource in the 'test' namespace
authorizer.group('apps').resource('deployments').namespace('test').name('') // returns a ResourceCheck for the 'deployments' resource in the 'test' namespace

check

For PathCheck, checks if the principal (user or service account) that sent the request is authorized for the HTTP request verb of the path. For ResourceCheck, checks if the principal (user or service account) that sent the request is authorized for the API verb and the configured authorization checks of the ResourceCheck. The check operation can be expensive, particularly in clusters using the webhook authorization mode. 

<PathCheck>.check(<check>) <Decision>
<ResourceCheck>.check(<check>) <Decision>

Examples: 

authorizer.group('').resource('pods').namespace('default').check('create') // Checks if the principal (user or service account) is authorized create pods in the 'default' namespace.
authorizer.path('/healthz').check('get') // Checks if the principal (user or service account) is authorized to make HTTP GET requests to the /healthz API path.

allowed

Returns true if the authorizer's decision for the check is "allow". Note that if the authorizer's decision is "no opinion", that the 'allowed' function will return false. 

<Decision>.allowed() <bool>

Examples: 

authorizer.group('').resource('pods').namespace('default').check('create').allowed() // Returns true if the principal (user or service account) is allowed create pods in the 'default' namespace.
authorizer.path('/healthz').check('get').allowed()  // Returns true if the principal (user or service account) is allowed to make HTTP GET requests to the /healthz API path.

reason

Returns a string reason for the authorization decision 

<Decision>.reason() <string>

Examples: 

authorizer.path('/healthz').check('GET').reason()

errored

Returns true if the authorization check resulted in an error. 

<Decision>.errored() <bool>

Examples: 

authorizer.group('').resource('pods').namespace('default').check('create').errored() // Returns true if the authorization check resulted in an error

error

If the authorization check resulted in an error, returns the error. Otherwise, returns the empty string. 

<Decision>.error() <string>

Examples: 

authorizer.group('').resource('pods').namespace('default').check('create').error()

func CIDR added in v0.30.0 

func CIDR() cel.EnvOption

CIDR provides a CEL function library extension of CIDR notation parsing functions.

cidr

Converts a string in CIDR notation to a network address representation or results in an error if the string is not a valid CIDR notation. The CIDR must be an IPv4 or IPv6 subnet address with a mask. Leading zeros in IPv4 address octets are not allowed. IPv4-mapped IPv6 addresses (e.g. ::ffff:1.2.3.4/24) are not allowed. 

cidr(<string>) <CIDR>

Examples: 

cidr('192.168.0.0/16') // returns an IPv4 address with a CIDR mask
cidr('::1/128') // returns an IPv6 address with a CIDR mask
cidr('192.168.0.0/33') // error
cidr('::1/129') // error
cidr('192.168.0.1/16') // error, because there are non-0 bits after the prefix

isCIDR

Returns true if a string is a valid CIDR notation respresentation of a subnet with mask. The CIDR must be an IPv4 or IPv6 subnet address with a mask. Leading zeros in IPv4 address octets are not allowed. IPv4-mapped IPv6 addresses (e.g. ::ffff:1.2.3.4/24) are not allowed. 

isCIDR(<string>) <bool>

Examples: 

isCIDR('192.168.0.0/16') // returns true
isCIDR('::1/128') // returns true
isCIDR('192.168.0.0/33') // returns false
isCIDR('::1/129') // returns false

containsIP / containerCIDR / ip / masked / prefixLength

- containsIP: Returns true if a the CIDR contains the given IP address. The IP address must be an IPv4 or IPv6 address. May take either a string or IP address as an argument.

- containsCIDR: Returns true if a the CIDR contains the given CIDR. The CIDR must be an IPv4 or IPv6 subnet address with a mask. May take either a string or CIDR as an argument.

- ip: Returns the IP address representation of the CIDR.

- masked: Returns the CIDR representation of the network address with a masked prefix. This can be used to return the canonical form of the CIDR network.

- prefixLength: Returns the prefix length of the CIDR in bits. This is the number of bits in the mask.

Examples:

cidr('192.168.0.0/24').containsIP(ip('192.168.0.1')) // returns true cidr('192.168.0.0/24').containsIP(ip('192.168.1.1')) // returns false cidr('192.168.0.0/24').containsIP('192.168.0.1') // returns true cidr('192.168.0.0/24').containsIP('192.168.1.1') // returns false cidr('192.168.0.0/16').containsCIDR(cidr('192.168.10.0/24')) // returns true cidr('192.168.1.0/24').containsCIDR(cidr('192.168.2.0/24')) // returns false cidr('192.168.0.0/16').containsCIDR('192.168.10.0/24') // returns true cidr('192.168.1.0/24').containsCIDR('192.168.2.0/24') // returns false cidr('192.168.0.1/24').ip() // returns ipAddr('192.168.0.1') cidr('192.168.0.1/24').ip().family() // returns '4' cidr('::1/128').ip() // returns ipAddr('::1') cidr('::1/128').ip().family() // returns '6' cidr('192.168.0.0/24').masked() // returns cidr('192.168.0.0/24') cidr('192.168.0.1/24').masked() // returns cidr('192.168.0.0/24') cidr('192.168.0.0/24') == cidr('192.168.0.0/24').masked() // returns true, CIDR was already in canonical format cidr('192.168.0.1/24') == cidr('192.168.0.1/24').masked() // returns false, CIDR was not in canonical format cidr('192.168.0.0/16').prefixLength() // returns 16 cidr('::1/128').prefixLength() // returns 128

func IP added in v0.30.0 

func IP() cel.EnvOption

IP provides a CEL function library extension of IP address parsing functions.

ip

Converts a string to an IP address or results in an error if the string is not a valid IP address. The IP address must be an IPv4 or IPv6 address. IPv4-mapped IPv6 addresses (e.g. ::ffff:1.2.3.4) are not allowed. IP addresses with zones (e.g. fe80::1%eth0) are not allowed. Leading zeros in IPv4 address octets are not allowed. 

ip(<string>) <IPAddr>

Examples: 

ip('127.0.0.1') // returns an IPv4 address
ip('::1') // returns an IPv6 address
ip('127.0.0.256') // error
ip(':::1') // error

isIP

Returns true if a string is a valid IP address. The IP address must be an IPv4 or IPv6 address. IPv4-mapped IPv6 addresses (e.g. ::ffff:1.2.3.4) are not allowed. IP addresses with zones (e.g. fe80::1%eth0) are not allowed. Leading zeros in IPv4 address octets are not allowed. 

isIP(<string>) <bool>

Examples: 

isIP('127.0.0.1') // returns true
isIP('::1') // returns true
isIP('127.0.0.256') // returns false
isIP(':::1') // returns false

ip.isCanonical

Returns true if the IP address is in its canonical form. There is exactly one canonical form for every IP address, so fields containing IPs in canonical form can just be treated as strings when checking for equality or uniqueness. 

ip.isCanonical(<string>) <bool>

Examples: 

ip.isCanonical('127.0.0.1') // returns true; all valid IPv4 addresses are canonical
ip.isCanonical('2001:db8::abcd') // returns true
ip.isCanonical('2001:DB8::ABCD') // returns false
ip.isCanonical('2001:db8::0:0:0:abcd') // returns false

family / isUnspecified / isLoopback / isLinkLocalMulticast / isLinkLocalUnicast / isGlobalUnicast

- family: returns the IP addresses' family (IPv4 or IPv6) as an integer, either '4' or '6'.

- isUnspecified: returns true if the IP address is the unspecified address. Either the IPv4 address "0.0.0.0" or the IPv6 address "::".

- isLoopback: returns true if the IP address is the loopback address. Either an IPv4 address with a value of 127.x.x.x or an IPv6 address with a value of ::1.

- isLinkLocalMulticast: returns true if the IP address is a link-local multicast address. Either an IPv4 address with a value of 224.0.0.x or an IPv6 address in the network ff00::/8.

- isLinkLocalUnicast: returns true if the IP address is a link-local unicast address. Either an IPv4 address with a value of 169.254.x.x or an IPv6 address in the network fe80::/10.

- isGlobalUnicast: returns true if the IP address is a global unicast address. Either an IPv4 address that is not zero or 255.255.255.255 or an IPv6 address that is not a link-local unicast, loopback or multicast address.

Examples:

ip('127.0.0.1').family() // returns '4” ip('::1').family() // returns '6' ip('127.0.0.1').family() == 4 // returns true ip('::1').family() == 6 // returns true ip('0.0.0.0').isUnspecified() // returns true ip('127.0.0.1').isUnspecified() // returns false ip('::').isUnspecified() // returns true ip('::1').isUnspecified() // returns false ip('127.0.0.1').isLoopback() // returns true ip('192.168.0.1').isLoopback() // returns false ip('::1').isLoopback() // returns true ip('2001:db8::abcd').isLoopback() // returns false ip('224.0.0.1').isLinkLocalMulticast() // returns true ip('224.0.1.1').isLinkLocalMulticast() // returns false ip('ff02::1').isLinkLocalMulticast() // returns true ip('fd00::1').isLinkLocalMulticast() // returns false ip('169.254.169.254').isLinkLocalUnicast() // returns true ip('192.168.0.1').isLinkLocalUnicast() // returns false ip('fe80::1').isLinkLocalUnicast() // returns true ip('fd80::1').isLinkLocalUnicast() // returns false ip('192.168.0.1').isGlobalUnicast() // returns true ip('255.255.255.255').isGlobalUnicast() // returns false ip('2001:db8::abcd').isGlobalUnicast() // returns true ip('ff00::1').isGlobalUnicast() // returns false

func Lists 

func Lists() cel.EnvOption

Lists provides a CEL function library extension of list utility functions.

isSorted

Returns true if the provided list of comparable elements is sorted, else returns false. 

<list<T>>.isSorted() <bool>, T must be a comparable type

Examples: 

[1, 2, 3].isSorted()  // return true
['a', 'b', 'b', 'c'].isSorted()  // return true
[2.0, 1.0].isSorted()  // return false
[1].isSorted()  // return true
[].isSorted()  // return true

sum

Returns the sum of the elements of the provided list. Supports CEL number (int, uint, double) and duration types. 

<list<T>>.sum() <T>, T must be a numeric type or a duration

Examples: 

[1, 3].sum() // returns 4
[1.0, 3.0].sum() // returns 4.0
['1m', '1s'].sum() // returns '1m1s'
emptyIntList.sum() // returns 0
emptyDoubleList.sum() // returns 0.0
[].sum() // returns 0

min / max

Returns the minimum/maximum valued element of the provided list. Supports all comparable types. If the list is empty, an error is returned. 

<list<T>>.min() <T>, T must be a comparable type
<list<T>>.max() <T>, T must be a comparable type

Examples: 

[1, 3].min() // returns 1
[1, 3].max() // returns 3
[].min() // error
[1].min() // returns 1
([0] + emptyList).min() // returns 0

indexOf / lastIndexOf

Returns either the first or last positional index of the provided element in the list. If the element is not found, -1 is returned. Supports all equatable types. 

<list<T>>.indexOf(<T>) <int>, T must be an equatable type
<list<T>>.lastIndexOf(<T>) <int>, T must be an equatable type

Examples: 

[1, 2, 2, 3].indexOf(2) // returns 1
['a', 'b', 'b', 'c'].lastIndexOf('b') // returns 2
[1.0].indexOf(1.1) // returns -1
[].indexOf('string') // returns -1

func NewAuthorizerVal added in v0.27.0 

func NewAuthorizerVal(userInfo user.Info, authorizer authorizer.Authorizer) ref.Val

func NewResourceAuthorizerVal added in v0.27.0 

func NewResourceAuthorizerVal(userInfo user.Info, authorizer authorizer.Authorizer, requestResource Resource) ref.Val

func Quantity added in v0.28.0 

func Quantity() cel.EnvOption

func Regex 

func Regex() cel.EnvOption

Regex provides a CEL function library extension of regex utility functions.

find / findAll

Returns substrings that match the provided regular expression. find returns the first match. findAll may optionally be provided a limit. If the limit is set and >= 0, no more than the limit number of matches are returned. 

<string>.find(<string>) <string>
<string>.findAll(<string>) <list <string>>
<string>.findAll(<string>, <int>) <list <string>>

Examples: 

"abc 123".find('[0-9]*') // returns '123'
"abc 123".find('xyz') // returns ''
"123 abc 456".findAll('[0-9]*') // returns ['123', '456']
"123 abc 456".findAll('[0-9]*', 1) // returns ['123']
"123 abc 456".findAll('xyz') // returns []

func Test added in v0.28.0 

func Test(options ...TestOption) cel.EnvOption

Test provides a test() function that returns true.

func TestVersion added in v0.28.0 

func TestVersion(version uint32) func(lib *testLib) *testLib

func URLs 

func URLs() cel.EnvOption

URLs provides a CEL function library extension of URL parsing functions.

url

Converts a string to a URL or results in an error if the string is not a valid URL. The URL must be an absolute URI or an absolute path. 

url(<string>) <URL>

Examples: 

url('https://user:pass@example.com:80/path?query=val#fragment') // returns a URL
url('/absolute-path') // returns a URL
url('https://a:b:c/') // error
url('../relative-path') // error

isURL

Returns true if a string is a valid URL. The URL must be an absolute URI or an absolute path. 

isURL( <string>) <bool>

Examples: 

isURL('https://user:pass@example.com:80/path?query=val#fragment') // returns true
isURL('/absolute-path') // returns true
isURL('https://a:b:c/') // returns false
isURL('../relative-path') // returns false

getScheme / getHost / getHostname / getPort / getEscapedPath / getQuery

Return the parsed components of a URL.

  • getScheme: If absent in the URL, returns an empty string.

  • getHostname: IPv6 addresses are returned without braces, e.g. "::1". If absent in the URL, returns an empty string.

  • getHost: IPv6 addresses are returned with braces, e.g. "[::1]". If absent in the URL, returns an empty string.

  • getEscapedPath: The string returned by getEscapedPath is URL escaped, e.g. "with space" becomes "with%20space". If absent in the URL, returns an empty string.

  • getPort: If absent in the URL, returns an empty string.

  • getQuery: Returns the query parameters in "matrix" form where a repeated query key is interpreted to mean that there are multiple values for that key. The keys and values are returned unescaped. If absent in the URL, returns an empty map.

    <URL>.getScheme() <string> <URL>.getHost() <string> <URL>.getHostname() <string> <URL>.getPort() <string> <URL>.getEscapedPath() <string> <URL>.getQuery() <map <string>, <list <string>>

Examples: 

url('/path').getScheme() // returns ''
url('https://example.com/').getScheme() // returns 'https'
url('https://example.com:80/').getHost() // returns 'example.com:80'
url('https://example.com/').getHost() // returns 'example.com'
url('https://[::1]:80/').getHost() // returns '[::1]:80'
url('https://[::1]/').getHost() // returns '[::1]'
url('/path').getHost() // returns ''
url('https://example.com:80/').getHostname() // returns 'example.com'
url('https://127.0.0.1:80/').getHostname() // returns '127.0.0.1'
url('https://[::1]:80/').getHostname() // returns '::1'
url('/path').getHostname() // returns ''
url('https://example.com:80/').getPort() // returns '80'
url('https://example.com/').getPort() // returns ''
url('/path').getPort() // returns ''
url('https://example.com/path').getEscapedPath() // returns '/path'
url('https://example.com/path with spaces/').getEscapedPath() // returns '/path%20with%20spaces/'
url('https://example.com').getEscapedPath() // returns ''
url('https://example.com/path?k1=a&k2=b&k2=c').getQuery() // returns { 'k1': ['a'], 'k2': ['b', 'c']}
url('https://example.com/path?key with spaces=value with spaces').getQuery() // returns { 'key with spaces': ['value with spaces']}
url('https://example.com/path?').getQuery() // returns {}
url('https://example.com/path').getQuery() // returns {}

Types

type CostEstimator 

type CostEstimator struct {
	// SizeEstimator provides a CostEstimator.EstimateSize that this CostEstimator will delegate size estimation
	// calculations to if the size is not well known (i.e. a constant).
	SizeEstimator checker.CostEstimator
}

CostEstimator implements CEL's interpretable.ActualCostEstimator and checker.CostEstimator.

func (*CostEstimator) CallCost 

func (l *CostEstimator) CallCost(function, overloadId string, args []ref.Val, result ref.Val) *uint64

func (*CostEstimator) EstimateCallCost 

func (l *CostEstimator) EstimateCallCost(function, overloadId string, target *checker.AstNode, args []checker.AstNode) *checker.CallEstimate

func (*CostEstimator) EstimateSize 

func (l *CostEstimator) EstimateSize(element checker.AstNode) *checker.SizeEstimate

type Resource added in v0.27.0 

type Resource interface {
	// GetName returns the name of the object as presented in the request.  On a CREATE operation, the client
	// may omit name and rely on the server to generate the name.  If that is the case, this method will return
	// the empty string
	GetName() string
	// GetNamespace is the namespace associated with the request (if any)
	GetNamespace() string
	// GetResource is the name of the resource being requested.  This is not the kind.  For example: pods
	GetResource() schema.GroupVersionResource
	// GetSubresource is the name of the subresource being requested.  This is a different resource, scoped to the parent resource, but it may have a different kind.
	// For instance, /pods has the resource "pods" and the kind "Pod", while /pods/foo/status has the resource "pods", the sub resource "status", and the kind "Pod"
	// (because status operates on pods). The binding resource for a pod though may be /pods/foo/binding, which has resource "pods", subresource "binding", and kind "Binding".
	GetSubresource() string
}

Resource represents an API resource

type TestOption added in v0.28.0 

type TestOption func(*testLib) *testLib

Source Files

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