mb::ContextStore Class Reference

#include <context_store.h>

Public Member Functions
	ContextStore ()=default
void	dump ()
	Convenience method for dumping context data for debugging.
bool	hasKey (const std::string &key) const
template<typename T >
void	set (const std::string &key, T value)
	Store a key-value data in the context.
template<typename T >
std::optional< T * >	get (const std::string &key)
	Get context value given the key.
template<typename T >
T &	getOr (const std::string &key, T default_value)
	Get context value given the key.

Detailed Description

The ContextStore class provides a means to set/get a key-value data that can be shared uniquely between middlewares and the handler functions. This allows sending data down the chain from the first to the last handler.

For instance, the auth middleware will inject user id and subsequent middlewares can retrieve it as needed.

// Create the object
Context ctx;
 
// Add values
ctx.set<std::string>("key", "Value");
ctx.set<int>("id", 967567);
ctx.set<bool>("verified", true);
 
// Retrieve values
 
// From scripting using JS
req.set("key", 5") // INT/DOUBLE/FLOATS ...
req.set("key2", { a: 5, b: 7}) // Objects/JSON
req.set("valid", true) // BOOLs
 
req.getOr("nothing", "Default Value")

The value returned from the get() is a std::optional, meaning a std::nullopt if the key was not found.

std::optional key = ctx.get<std::string>("key");
if(key.has_value()) { .... }

Additionally, we have a

See also

get_or() method that takes in a key and a default value if the key is missing. This unlike

get() method, returns a T& instead of T* depending on the usage needs.

Constructor & Destructor Documentation

ContextStore()

mb::ContextStore::ContextStore ( )

default

Member Function Documentation

dump()

void mb::ContextStore::dump

(

)

Convenience method for dumping context data for debugging.

get()

template<typename T >

std::optional< T * > mb::ContextStore::get ( const std::string &  key )

inline

Get context value given the key.

Template Parameters

T	Value data type

Parameters

key

Value key

Returns

Value wrapped in a std::optional

getOr()

template<typename T >

T & mb::ContextStore::getOr ( const std::string &  key, T  default_value  )

inline

Get context value given the key.

Template Parameters

T	Value data type

Parameters

key	Value key
default_value	Default value if key is missing

Returns

Value or default value

hasKey()

bool mb::ContextStore::hasKey

(

const std::string &

key

)

const

Parameters

key	Key to check in context store

Returns

true if key exists, else, false

set()

template<typename T >

void mb::ContextStore::set ( const std::string &  key, T  value  )

inline

Store a key-value data in the context.

Template Parameters

T	Value data type

Parameters

key	Value key
value	Value to be stored

---

The documentation for this class was generated from the following files:

• /home/runner/work/mantisbase/mantisbase/include/mantisbase/core/context_store.h
• /home/runner/work/mantisbase/mantisbase/src/core/context_store.cpp