48 lines
1.1 KiB
Markdown
48 lines
1.1 KiB
Markdown
---
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tags: api/syscall
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references:
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- client/service_registry.ts
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- client/plugos/syscalls/service_registry.ts
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---
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The Service API exposes a simple service registry leveraged by various parts of SilverBullet. See [[Service]].
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${spacelua.renderApiDocumentation("service")}
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# Architecture
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Services are built on top of [[Event|Events]]. When a service is defined, it registers two event listeners:
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1. `discover:<<selector>>` for service discovery
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2. `service:<<guid>>` for invocation
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Discovery broadcasts on the event bus and collects all matches, sorted by priority. Invocation calls the specific service's `run` callback.
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# Example
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```space-lua
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service.define {
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selector = "greeter-service",
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match = {},
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run = function(name)
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return "Hello " .. name
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end
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}
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service.define {
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selector = "greeter-service",
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match = function(name)
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if name == "Pete" then
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return {priority=10}
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else
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return nil
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end
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end,
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run = function(name)
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return "Hello Pete, so happy to see you!"
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end
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}
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```
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To invoke: ${service.invokeBestMatch("greeter-service", "Pete")} and ${service.invokeBestMatch("greeter-service", "Hank")}
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