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MyFirstApp: Durability section for gophercloud

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Adding the code for interact with the object storage service with go.

Change-Id: I4f994b6f8ccfca0ab858a062c9243c3a66197ddd
This commit is contained in:
Marcela Bonell 2017-02-23 18:33:51 -06:00
parent e4cc768760
commit eca87c81a4
2 changed files with 224 additions and 0 deletions
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158
firstapp/samples/gophercloud/durability.go Normal file
View File

@ -0,0 +1,158 @@
package main
import (
"bufio"
"encoding/json"
"fmt"
"io"
"io/ioutil"
"net/http"
"os"
"github.com/gophercloud/gophercloud"
"github.com/gophercloud/gophercloud/openstack"
"github.com/gophercloud/gophercloud/openstack/objectstorage/v1/containers"
"github.com/gophercloud/gophercloud/openstack/objectstorage/v1/objects"
"github.com/gophercloud/gophercloud/pagination"
)
func main() {
// step-1
authOpts, err := openstack.AuthOptionsFromEnv()
if err != nil {
fmt.Println(err)
return
}
provider, err := openstack.AuthenticatedClient(authOpts)
if err != nil {
fmt.Println(err)
return
}
var regionName = os.Getenv("OS_REGION_NAME")
objectClient, err := openstack.NewObjectStorageV1(provider, gophercloud.EndpointOpts{
Region: regionName,
})
if err != nil {
fmt.Println(err)
return
}
// step-2
containerName := "fractals"
containers.Create(objectClient, containerName, nil)
// step-3
containers.List(objectClient, &containers.ListOpts{}).EachPage(func(page pagination.Page) (bool, error) {
containerList, _ := containers.ExtractNames(page)
for _, name := range containerList {
fmt.Printf("Container name [%s] \n", name)
}
return true, nil
})
// step-4
filePath := "goat.jpg"
objectName := "an amazing goat"
f, _ := os.Open(filePath)
defer f.Close()
reader := bufio.NewReader(f)
options := objects.CreateOpts{
Content: reader,
}
objects.Create(objectClient, containerName, objectName, options)
// step-5
objects.List(objectClient, containerName, &objects.ListOpts{}).EachPage(func(page pagination.Page) (bool, error) {
objectList, _ := objects.ExtractNames(page)
for _, name := range objectList {
fmt.Printf("Object name [%s] \n", name)
}
return true, nil
})
// step-6
// step-7
// step-8
objects.Delete(objectClient, containerName, objectName, nil)
// step-9
// step-10
containerName = "fractals"
containers.Create(objectClient, containerName, nil)
// step-11
endpoint := "http://IP_API_1"
resp, _ := http.Get(endpoint + "/v1/fractal")
defer resp.Body.Close()
body, _ := ioutil.ReadAll(resp.Body)
type Fractal struct {
UUID string `json:"uuid"`
}
type Data struct {
Results int `json:"num_results"`
Objects []Fractal `json:"objects"`
Page int `json:"page"`
TotalPages int `json:"total_pages"`
}
var data Data
json.Unmarshal([]byte(body), &data)
for _, fractal := range data.Objects {
r, _ := http.Get(endpoint + "/fractal/" + fractal.UUID)
defer r.Body.Close()
image := fractal.UUID + ".png"
out, _ := os.Create(image)
defer out.Close()
io.Copy(out, r.Body)
f, _ := os.Open(image)
defer f.Close()
reader := bufio.NewReader(f)
options := objects.CreateOpts{
Content: reader,
}
objectName = fractal.UUID
fmt.Printf("Uploading object [%s] in container [%s]... \n", objectName, containerName)
objects.Create(objectClient, containerName, objectName, options)
}
objects.List(objectClient, containerName, &objects.ListOpts{}).EachPage(func(page pagination.Page) (bool, error) {
objectList, _ := objects.ExtractNames(page)
for _, name := range objectList {
fmt.Printf("Object [%s] in container [%s] \n", name, containerName)
}
return true, nil
})
// step-12
objects.List(objectClient, containerName, &objects.ListOpts{}).EachPage(func(page pagination.Page) (bool, error) {
objectList, _ := objects.ExtractNames(page)
for _, name := range objectList {
fmt.Printf("Deleting object [%s] in container [%s]... \n", name, containerName)
objects.Delete(objectClient, containerName, name, nil)
}
return true, nil
})
fmt.Printf("Deleting container [%s] \n", containerName)
containers.Delete(objectClient, containerName)
// step-13
objects.Update(objectClient, containerName, objectName, &objects.UpdateOpts{Metadata: map[string]string{"foo": "bar"}})
// step-14
}

66
firstapp/source/durability.rst
View File

@ -123,6 +123,13 @@ First, learn how to connect to the Object Storage endpoint:
:start-after: step-1
:end-before: step-2
.. only:: gophercloud
.. literalinclude:: ../samples/gophercloud/durability.go
:language: go
:start-after: step-1
:end-before: step-2
To begin to store objects, we must first make a container.
Call yours :code:`fractals`:
@ -173,6 +180,12 @@ Call yours :code:`fractals`:
u'txc6262b9c2bc1445b9dfe3-00574277ff', u'date': u'Mon, 23 May 2016
03:24:47 GMT', u'content-type': u'text/plain; charset=utf-8'})
.. only:: gophercloud
.. literalinclude:: ../samples/gophercloud/durability.go
:language: go
:start-after: step-2
:end-before: step-3
You should now be able to see this container appear in a listing of
all containers in your account:
@ -219,6 +232,13 @@ all containers in your account:
[Munch({u'count': 0, u'bytes': 0, u'name': u'fractals'}),
Munch({u'count': 0, u'bytes': 0, u'name': u'fractals_segments'})]
.. only:: gophercloud
.. literalinclude:: ../samples/gophercloud/durability.go
:language: go
:start-after: step-3
:end-before: step-4
The next logical step is to upload an object. Find a photo of a goat
online, name it :code:`goat.jpg`, and upload it to your
:code:`fractals` container:
@ -248,6 +268,13 @@ online, name it :code:`goat.jpg`, and upload it to your
:start-after: step-4
:end-before: step-5
.. only:: gophercloud
.. literalinclude:: ../samples/gophercloud/durability.go
:language: go
:start-after: step-4
:end-before: step-5
List objects in your :code:`fractals` container to see if the upload
was successful. Then, download the file to verify that the md5sum is
the same:
@ -364,6 +391,13 @@ the same:
d1408b5bf6510426db6e2bafc2f90854
.. only:: gophercloud
.. literalinclude:: ../samples/gophercloud/durability.go
:language: go
:start-after: step-5
:end-before: step-6
Finally, clean up by deleting the test object:
.. only:: fog
@ -421,6 +455,12 @@ Finally, clean up by deleting the test object:
[]
.. only:: gophercloud
.. literalinclude:: ../samples/gophercloud/durability.go
:language: go
:start-after: step-8
:end-before: step-9
Back up the Fractals from the database on the Object Storage
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@ -455,6 +495,13 @@ Place the images in the :code:`fractals` container:
:start-after: step-10
:end-before: step-11
.. only:: gophercloud
.. literalinclude:: ../samples/gophercloud/durability.go
:language: go
:start-after: step-10
:end-before: step-11
Next, back up all existing fractals from the database to the swift container.
A simple loop takes care of that:
@ -502,6 +549,12 @@ A simple loop takes care of that:
Before you try to run the previous script, make sure that
it is installed on your system.
.. only:: gophercloud
.. literalinclude:: ../samples/gophercloud/durability.go
:language: go
:start-after: step-11
:end-before: step-12
Configure the Fractals app to use Object Storage
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@ -544,6 +597,13 @@ Otherwise, the delete operation fails:
:start-after: step-12
:end-before: step-13
.. only:: gophercloud
.. literalinclude:: ../samples/gophercloud/durability.go
:language: go
:start-after: step-12
:end-before: step-13
.. warning:: It is not possible to restore deleted objects. Be careful.
Add metadata to objects
@ -598,6 +658,12 @@ your SDK.
:start-after: step-13
:end-before: step-14
.. only:: gophercloud
.. literalinclude:: ../samples/gophercloud/durability.go
:language: go
:start-after: step-13
:end-before: step-14
Large objects
~~~~~~~~~~~~~