PARTICLES POINTERS & KINDS

PARTICLES

A Particle is a resource which can send and receive Waves (messages).

KIND

Particles differ in functionality by their Kind. For example a User Particle will accept different types of Waves than a FileSystem Particle. They do different things.

DENOTATION

Kinds are denoted in angle brackets:

<Space>

Space is a single Base Kind without any Sub Kinds.

SUBS

Kinds can be hierarchical and are notated using delimited angle brackets like so:

<Base<Sub>>

Above you can see that a Base Kind and a Sub Kind are denoted.

For example to reference a Relational database you would denote it like this:

<Database<Rel>>

And You would reference a Graph database like this:

<Database<Graph>>

The more specific the Sub Kind the more custom functionality you can access in the Particle’s API.

SPECIFIC

There is one more rung in the Kind hierarchy which is a Specific.

Here is an example of a Specific:

mechtronhub.io:postgres.org:postgres:gis:12.0.0

And it would go with the rest of our Kind definition like this:

<Database<Rel<mechtronhub.io:postgres.org:postgres:gis:12.0.0>>>

A Specific identifies an EXACT implementation of a Particle.

The various parts of the specific can be broken down as follows:

provider-domain:vendor-domain:product:variant:version

Provider Domain is the provider of the one supplying the Driver for the given Kind… which may not be the same as the vendor that actually supplies the product.

POINT

Every particle has a Point which acts as an address and unique identifier. The Particles Point is used in security, searching, message routing, logging and more.

Points are hierarchical and are usually delimited by a ‘:’. Here is an example of a Point:

my-domain.com:users:my-user

Notice above the first Point Segment my-domain.com is a domain name and in fact the first segment MUST be a lowercase valid hostname or domain name. The first segment is also required to be a Space Kind.

Also note that only the Space segment is allowed to have dots in it, the rest of the Base segments are lowercase kebab.

POINT + KIND

Point & Kind can be put together when referencing a Particle like this:

my-domain.com:users:my-user<User>

As you can see the Particle is identified by Point and Kind by immediately appending the Kind denotation after the Point.

FILESYSTEM POINTS

When referencing the children of a FileSystem Particle the Point Rules change a little.

my-domain.com:my-files:/some-file.txt

Notice that there is now a leading slash (which identifies the root of the FileSystem). Once the point segments pass a slash the rules change so that segments are delimited by slashes, and they can have any valid file characters.

Here is Another example showing directory structure:

my-domain.com:my-files:/some-dir/My-file.txt

Again, notice that My-file.txt has a capital letter in it, not allowed in the regular Base segments, but perfectly allowed once the transition is made to FileSystem segments.

ARTIFACT BUNDLES

Artifact Bundles are zip files that can be downloaded and cached by other services. They exist in a repo and are versioned. A Bundle must live underneath an ArtifactBundleSeries which in turn must be under a Repo.

Since a Bundle is versioned its Point Segment is a version number:

my-domain:repo:my-bundle-series:1.0.0

It is required that after a version is declared remaining segments will use FileSystem style which makes sense because an Artifact Bundle is really just a zip file. In order to reference an artifact:

my-domain:repo:my-bundle-series:1.0.0:/bind/my-particle.bind

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