graphql-engine/cli/commands/metadata.go
Jeff Sieu 2ee7f7d76e cli(metadata): add diff command and dry-run flag (#3157)
### Description
Adds a `metadata diff` command to show comparisons between two different sets of Hasura metadata.
```
# Show changes between server metadata and the exported metadata file:
hasura metadata diff

# Show changes between server metadata and that in local_metadata.yaml:
hasura metadata diff local_metadata.yaml

# Show changes between metadata from metadata.yaml and metadata_old.yaml:
hasura metadata diff metadata.yaml metadata_old.yaml
```

Also adds a `--dry-run` flag to `metadata apply` command which will print the diff and exit rather than actually applying the metadata.

### Affected components 
- CLI
- Docs

### Related Issues
Close #3126, Close #3127

### Solution and Design
- Added `metadata_diff.go` and `metadata_diff_test.go`


### Steps to test and verify
```
hasura metadata export
# Make changes to migrations/metadata.yaml
hasura metadata diff
```

### Limitations, known bugs & workarounds
This is just a general-purpose diff. 

A more contextual diff with the understanding of metadata can be added once #3072  is merged.
2019-10-30 19:24:22 +05:30

104 lines
2.3 KiB
Go

package commands
import (
"encoding/json"
"io/ioutil"
"os"
"github.com/ghodss/yaml"
"github.com/hasura/graphql-engine/cli"
"github.com/hasura/graphql-engine/cli/migrate"
"github.com/pkg/errors"
"github.com/spf13/cobra"
)
func NewMetadataCmd(ec *cli.ExecutionContext) *cobra.Command {
metadataCmd := &cobra.Command{
Use: "metadata",
Short: "Manage Hasura GraphQL Engine metadata saved in the database",
SilenceUsage: true,
}
metadataCmd.AddCommand(
newMetadataDiffCmd(ec),
newMetadataExportCmd(ec),
newMetadataClearCmd(ec),
newMetadataReloadCmd(ec),
newMetadataApplyCmd(ec),
)
return metadataCmd
}
func executeMetadata(cmd string, t *migrate.Migrate, ec *cli.ExecutionContext) error {
switch cmd {
case "export":
metaData, err := t.ExportMetadata()
if err != nil {
return errors.Wrap(err, "cannot export metadata")
}
t, err := json.Marshal(metaData)
if err != nil {
return errors.Wrap(err, "cannot Marshal metadata")
}
data, err := yaml.JSONToYAML(t)
if err != nil {
return err
}
metadataPath, err := ec.GetMetadataFilePath("yaml")
if err != nil {
return errors.Wrap(err, "cannot save metadata")
}
err = ioutil.WriteFile(metadataPath, data, 0644)
if err != nil {
return errors.Wrap(err, "cannot save metadata")
}
case "clear":
err := t.ResetMetadata()
if err != nil {
return errors.Wrap(err, "cannot clear Metadata")
}
case "reload":
err := t.ReloadMetadata()
if err != nil {
return errors.Wrap(err, "cannot reload Metadata")
}
case "apply":
var data interface{}
var metadataContent []byte
for _, format := range []string{"yaml", "json"} {
metadataPath, err := ec.GetMetadataFilePath(format)
if err != nil {
return errors.Wrap(err, "cannot apply metadata")
}
metadataContent, err = ioutil.ReadFile(metadataPath)
if err != nil {
if os.IsNotExist(err) {
continue
}
return err
}
break
}
if metadataContent == nil {
return errors.New("Unable to locate metadata.[yaml|json] file under migrations directory")
}
err := yaml.Unmarshal(metadataContent, &data)
if err != nil {
return errors.Wrap(err, "cannot parse metadata file")
}
err = t.ApplyMetadata(data)
if err != nil {
return errors.Wrap(err, "cannot apply metadata on the database")
}
return nil
}
return nil
}