Bundle Properties

A C++ Micro Services Bundle provides meta-data in the form of so-called properties about itself. Properties are key - value pairs where the key is of type std::string and the value of type Any. The following properties are always set by the C++ Micro Services library and cannot be altered by the bundle author:

  • bundle.id - The unique id of the bundle (type long)

  • bundle.location - The full path to the bundle’s shared library on the file system (type std::string)

Bundle authors must always add the following property to their bundle’s manifest.json file:

  • bundle.symbolic_name - The human readable name of the bundle (type std::string). The name must start with either an underscore or letter and contain only underscores, letters, or numbers (i.e. must be a correct c-identifier).

C++ Micro Services will not install any bundle which doesn’t contain a valid ‘bundle.symbolic_name’ property in its manifest.json file.

Bundle authors can add custom properties by providing a manifest.json file, embedded as a top-level resource into the bundle (see The Resource System). The root value of the JSON file must be a JSON object. An example manifest.json file would be:

{
  "bundle.symbolic_name" : "my bundle",
  "bundle.version" : "1.0.2",
  "bundle.description" : "This bundle provides an awesome service",
  "authors" : [ "John Doe", "Douglas Reynolds", "Daniel Cannady" ],
  "rating" : 5
}

All JSON member names of the root object will be available as property keys in the bundle containing the manifest.json file. The C++ Micro Services library specifies the following standard keys for re-use in manifest.json files:

  • bundle.version - The version of the bundle (type std::string). The version string must be a valid version identifier, as specified in the BundleVersion class.

  • bundle.vendor - The vendor name of the bundle (type std::string)

  • bundle.description - A description for the bundle (type std::string)

Note

Some of the properties mentioned above may also be accessed via dedicated methods in the Bundle class, e.g. GetSymbolicName() or GetVersion().

Attention

Despite JSON being a case-sensitive format, C++ Micro Services stores bundle properties as case-insensitive to accommodate LDAP queries using LDAPFilter and LDAPProp. Either keep the JSON case-insensitive or standardize on a convention to ensure queries return the correct results.

When parsing the manifest.json file, the JSON types are mapped to C++ types and stored in instances of the Any class. The mapping is as follows:

JSON

C++ (Any)

object

std::map

array

std::vector

string

std::string

number

int or double

true

bool

false

bool

null

Any()