There are 5 levels of access rights: model, actions, field, button and record.
Every access right is based on the groups of the user.
The model and field access rights are checked for every RPC call for which
trytond.rpc.RPC.check_access is set. The others are always enforced.
They are defined by records of ir.model.access which define for each couple of model and group, the read, write, create and delete permission. If any group of the user has the permission activated, then the user is granted this permission.
Each action define a list of groups that are allowed to use it. There is a special case for ref:wizard <topics-wizard> for which the read access on the model is also checked and also the write access if there is no groups linked.
Same as for model access but applied on the field. It uses records of ir.model.field.access.
They are defined by records of ir.rule.group which contains a list of ir.rule domain to which the rule applies. The group are selected by groups or users. The access is granted for a record:
- if the user is in at least one group that has the permission activated,
- or if the user is in no group by there is a default group with the permission,
- or if there is a global group with the permission.