Documentation
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Index ¶
- type Graph
- func (g *Graph) CanExecuteNode(name string) bool
- func (g *Graph) GetAllRunnableNodes() []string
- func (g *Graph) GetTargetSubgraph(targetName string) (*Graph, error)
- func (g *Graph) GetUnit(name string) (Unit, error)
- func (g *Graph) IsStuck() bool
- func (g *Graph) Load(basepath string) error
- func (g *Graph) MarkNodesRun(names ...string) error
- func (g *Graph) RemainingSize() int
- func (g *Graph) Size() int
- func (g *Graph) ValidateNodes() error
- type PostgresDialect
- type SQLSection
- type Unit
- type UnitType
Constants ¶
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Variables ¶
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Functions ¶
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Types ¶
type Graph ¶
type Graph struct {
// contains filtered or unexported fields
}
Graph represents a set of unit files with dependencies that form a Direct Acyclic Graph.
func NewGraph ¶
func NewGraph() *Graph
NewGraph creates a graph that only contains the "nothing" unit which is used to bootstrap units without dependencies.
This is necessary because the graph has no concept of a node without dependency. This makes determining executable nodes much easier (search for nodes with executed dependencies instead of the former *and* searching for nodes without dependencies)
func (*Graph) CanExecuteNode ¶
CanExecuteNode returns true if the specified node is executeable, if the key is not present or the node cannot be executed, it return false
func (*Graph) GetAllRunnableNodes ¶
GetAllRunnableNodes returns a list of all nodes that can be executed on the current graph or an empty slice.
func (*Graph) GetTargetSubgraph ¶
GetTargetSubgraph will take a target and create a graph that only contains nodes that are direct or indirect dependencies of that target. If a unit is not reachable from the current target, it will not be included in the subgraph.
func (*Graph) IsStuck ¶
IsStuck determines if the graph can continue to execute nodes. To check this, IsStick counts how many unexecuted nodes are on the graph and then checks if any nodes can be executed. If there are unexecuted nodes but we cannot execute any nodes, then we are stuck. To ensure this check does not trigger, you should select a target and use GetTargetSubgraph to obtain a graph only containing the target's dependencies, direct or indirect.
func (*Graph) Load ¶
Load will use go.rice to load an embedded resources (or from LocalFS if not found) into the graph
func (*Graph) MarkNodesRun ¶
MarkNodesRun will mark a node as executed on the graph, allowing the graph to proceed the execution.
func (*Graph) RemainingSize ¶
RemainingSize indicates how many nodes need to be executed still
func (*Graph) ValidateNodes ¶
ValidateNodes will check that the graph is properly formed but will not check for cycles.
A properly formed graph contains nodes where their key in the internal map and their name match, that nodes always have a dependency if they have not been executed and that the dependencies of all nodes exist.
If this function returns no error then it is guaranteed that the graph is directed and may be acyclic.
type PostgresDialect ¶
type PostgresDialect struct {
// contains filtered or unexported fields
}
PostgresDialect implements a Postgres compatible interface to perform database migration using the mig toolkit
func OpenFromPGConn ¶
func OpenFromPGConn(db *sql.DB) *PostgresDialect
OpenFromPGConn accepts a opened database connections and wraps it into the PostgresDialect
func (*PostgresDialect) CheckAndLoadTables ¶
func (d *PostgresDialect) CheckAndLoadTables() error
CheckAndLoadTables will determine if the database is reachable and create the migration table
func (*PostgresDialect) GetExecutedUnits ¶
func (d *PostgresDialect) GetExecutedUnits() ([]string, error)
GetExecutedUnits returns a list of executed units present in the migration table
func (*PostgresDialect) MarkExecuted ¶
func (d *PostgresDialect) MarkExecuted(unit Unit) error
MarkExecuted will put a unit into the migration table unless it's marked as "always_exec: true" or a target unit
type SQLSection ¶
type SQLSection struct {
// Postgres contains the PG/SQL string to be executed for the unit
Postgres string `yaml:"postgres"`
}
SQLSection defines the SQLQueries for various dialects. At the moment only postgres is implemented since a graph-based migration requires a DDL-level transaction to be safe
type Unit ¶
type Unit struct {
Name string `yaml:"-"`
Description string `yaml:"description"`
DependsOn []string `yaml:"depends_on"`
AlwaysExec bool `yaml:"always_exec"`
Type UnitType `yaml:"type"`
SQL SQLSection `yaml:"sql"`
// contains filtered or unexported fields
}
Unit contains the definition of a migration unit that is represented by a node in a DAG
func (Unit) DependsOnWithoutNothing ¶
DependsOnWithoutNothing returns the list of dependencies that are not "nothing" Normally a unit should not depend on the "nothing" unit if it has other dependencies.
type UnitType ¶
type UnitType string
UnitType defines how a unit is treated on the graph
const ( // UnitTypeMigration defines a migration unit which executed SQLCode UnitTypeMigration UnitType = "migration" // UnitTypeVirtualTarget defines a target unit which groups various units together without executing code UnitTypeVirtualTarget = "target" )
Source Files