Synapse_handler configuration is not working as mentioned in the documentation

[chanikag]

Description

Below is the configuration you have to add to enable a synapse handler

[synapse_handlers.<custom_handler_name>]
 enabled=true
 class="org.wso2.carbon.apimgt.gateway.handlers.<Custom_Handler_Class>"

Related PRs:

wso2/docs-apim#8214
wso2/docs-apim#8220
wso2/docs-apim#8221
wso2/docs-apim#8222
wso2/docs-apim#8223

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[SanojPunchihewa]

AFAIK, we need to use the following format added via #258 to configure a Synapse handler in MI

[[synapse_handlers]]
name = "<handlerName>"
class = "<packageName>.<handlerName>"

[gspadotto]

Hi, I think @SanojPunchihewa is almost right (the suffix of the "class" entry, after the last full stop is the CLASS name, not the HANDLER name).

I would personally keep the current format to avoid refactorings for deployment.toml files that define SynapseHandlers.

With the current format, the only way of disabling an handler is by commenting it out in deployment.toml.

If you want to enable/disable a specific handler without commenting it out, then you might add the "enabled" boolean property with an explicit value of "false" (the default being "true"), like this:

[[synapse_handlers]]
name="<handlerName>"
class="<packageName>.<handlerClassName>"
enabled=false

It would also be nice to know/define what the triggering order of multiple handlers is.

Are they triggered in the same order in which they are defined in the deployment.toml file (thus SynapseHandlers are kept in a LIST) or the triggering order is undefined (thus SynapseHandlers are kept in a SET)?

In the latter case, it could be useful to add yet another attribute (like for IdentityHandlers): "priority".

If HandlerB must be triggered after HandlerA, then this snippet could express this requirement (assuming that handlers with lower values of priority are executed before handlers with higher values of priority):

[[synapse_handlers]]
name="HandlerA"
class="<packageName>.HandlerAImplementationClass"
priority=100

[[synapse_handlers]]
name="HandlerB"
class="<packageName>.HandlerBImplementationClass"
priority=200

All handlers that do not require being triggered in a specific order will not define their priority (as per current implementation).