Object Storage Service:Document format conversion

Scenarios

• Online preview optimization: After uploading PDF, Word, Excel, PPT, and other documents to OSS, you can call the document conversion interface to convert documents into images for direct preview on web or mobile devices without downloading.

• Cross-platform compatibility: Through document conversion services, users with different devices and operating systems can view documents seamlessly.

Supported input file types

How to use

import com.aliyun.oss.ClientBuilderConfiguration;
import com.aliyun.oss.OSS;
import com.aliyun.oss.OSSClientBuilder;
import com.aliyun.oss.common.auth.CredentialsProviderFactory;
import com.aliyun.oss.common.auth.EnvironmentVariableCredentialsProvider;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.model.AsyncProcessObjectRequest;
import com.aliyun.oss.model.AsyncProcessObjectResult;
import com.aliyuncs.exceptions.ClientException;

import java.util.Base64;

public class Demo1 {
    public static void main(String[] args) throws ClientException {
        // Specify the endpoint of the region in which the bucket is located.
        String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
        // Specify the ID of the Alibaba Cloud region in which the bucket is located. Example: cn-hangzhou.
        String region = "cn-hangzhou";
        // Obtain a credential from the environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured.
        EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
        // Specify the name of the bucket.
        String bucketName = "examplebucket";
        // Specify the name of the output object.
        String targetKey = "dest.png";
        // Specify the name of the source document.
        String sourceKey = "src.docx";

        // Create an OSSClient instance.
        // When the OSSClient instance is no longer in use, call the shutdown method to release resources.
        ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
        clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);
        OSS ossClient = OSSClientBuilder.create()
                .endpoint(endpoint)
                .credentialsProvider(credentialsProvider)
                .clientConfiguration(clientBuilderConfiguration)
                .region(region)
                .build();

        try {
            // Create a style variable of the string type to store document conversion parameters.
            String style = String.format("doc/convert,target_png,source_docx");
            // Create an asynchronous processing instruction.
            String bucketEncoded = Base64.getUrlEncoder().withoutPadding().encodeToString(bucketName.getBytes());
            String targetEncoded = Base64.getUrlEncoder().withoutPadding().encodeToString(targetKey.getBytes());
            String process = String.format("%s|sys/saveas,b_%s,o_%s", style, bucketEncoded, targetEncoded);
            // Create an AsyncProcessObjectRequest object.
            AsyncProcessObjectRequest request = new AsyncProcessObjectRequest(bucketName, sourceKey, process);
            // Execute the asynchronous processing task.
            AsyncProcessObjectResult response = ossClient.asyncProcessObject(request);
            System.out.println("EventId: " + response.getEventId());
            System.out.println("RequestId: " + response.getRequestId());
            System.out.println("TaskId: " + response.getTaskId());

        } finally {
            // Close your OSSClient.
            ossClient.shutdown();
        }
    }
}

# -*- coding: utf-8 -*-
import base64
import oss2
from oss2.credentials import EnvironmentVariableCredentialsProvider

def main():
    # Obtain the temporary access credentials from the environment variables. Before you execute the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured.
    auth = oss2.ProviderAuthV4(EnvironmentVariableCredentialsProvider())
    # Specify the endpoint for the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com.
    endpoint = 'https://oss-cn-hangzhou.aliyuncs.com'
    # Specify the ID of the Alibaba Cloud region in which the bucket is located. Example: cn-hangzhou.
    region = 'cn-hangzhou'

    # Specify the name of the bucket. Example: examplebucket.
    bucket = oss2.Bucket(auth, endpoint, 'examplebucket', region=region)

    # Specify the name of the source document.
    source_key = 'src.docx'

    # Specify the name of the output object.
    target_key = 'dest.png'

    # Create a style variable of the string type to store document conversion parameters.
    animation_style = 'doc/convert,target_png,source_docx'

    # Create a processing instruction, in which the name of the bucket and the name of the output object are Base64-encoded.
    bucket_name_encoded = base64.urlsafe_b64encode('examplebucket'.encode()).decode().rstrip('=')
    target_key_encoded = base64.urlsafe_b64encode(target_key.encode()).decode().rstrip('=')
    process = f"{animation_style}|sys/saveas,b_{bucket_name_encoded},o_{target_key_encoded}"

    try:
        # Execute the asynchronous processing task.
        result = bucket.async_process_object(source_key, process)
        print(f"EventId: {result.event_id}")
        print(f"RequestId: {result.request_id}")
        print(f"TaskId: {result.task_id}")
    except Exception as e:
        print(f"Error: {e}")


if __name__ == "__main__":
    main()

package main

import (
    "encoding/base64"
    "fmt"
    "os"
    "github.com/aliyun/aliyun-oss-go-sdk/oss"
    "log"
)

func main() {
    // Obtain the temporary access credentials from the environment variables. Before you execute the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured.
    provider, err := oss.NewEnvironmentVariableCredentialsProvider()
    if err != nil {
    fmt.Println("Error:", err)
    os.Exit(-1)
    }
    // Create an OSSClient instance.
    // Specify the endpoint of the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com. Specify your actual endpoint.
    // Specify the ID of the Alibaba Cloud region in which the bucket is located. Example: cn-hangzhou.
    client, err := oss.New("https://oss-cn-hangzhou.aliyuncs.com", "", "", oss.SetCredentialsProvider(&provider), oss.AuthVersion(oss.AuthV4), oss.Region("cn-hangzhou"))
    if err != nil {
    fmt.Println("Error:", err)
    os.Exit(-1)
    }
    // Specify the name of the bucket. Example: examplebucket.
    bucketName := "examplebucket"

    bucket, err := client.Bucket(bucketName)
    if err != nil {
    fmt.Println("Error:", err)
    os.Exit(-1)
    }

    // Specify the name of the source document.
    sourceKey := "src.docx"
    // Specify the name of the output object.
    targetKey := "dest.png"

    // Create a style variable of the string type to store document conversion parameters.
    animationStyle := "doc/convert,target_png,source_docx"

    // Create a processing instruction, in which the name of the bucket and the name of the output object are Base64-encoded.
    bucketNameEncoded := base64.URLEncoding.EncodeToString([]byte(bucketName))
    targetKeyEncoded := base64.URLEncoding.EncodeToString([]byte(targetKey))
    process := fmt.Sprintf("%s|sys/saveas,b_%v,o_%v", animationStyle, bucketNameEncoded, targetKeyEncoded)

    // Execute the asynchronous processing task.
    result, err := bucket.AsyncProcessObject(sourceKey, process)
    if err != nil {
    log.Fatalf("Failed to async process object: %s", err)
    }

    fmt.Printf("EventId: %s\n", result.EventId)
    fmt.Printf("RequestId: %s\n", result.RequestId)
    fmt.Printf("TaskId: %s\n", result.TaskId)
}

Parameter description

Action: doc/convert

The following table describes the parameters for document conversion.

You need to use the sys/saveas parameter to save the converted document in the specified bucket. For more information, see Save As. If you need to obtain the processing result of the conversion task, you need to use the notify parameter. For more information, see Notifications.

More scenarios

Document format conversion is submitted as an asynchronous request, which means that you cannot directly obtain the document conversion result (such as processing success or failure information) when the processing result is returned. If you need to obtain the processing result, we recommend that you configure event notifications with Simple Message Queue (SMQ, formerly MNS) to receive instant notifications after processing is completed, without the need to repeatedly query the task status.

import com.aliyun.oss.ClientBuilderConfiguration;
import com.aliyun.oss.OSS;
import com.aliyun.oss.OSSClientBuilder;
import com.aliyun.oss.common.auth.CredentialsProviderFactory;
import com.aliyun.oss.common.auth.EnvironmentVariableCredentialsProvider;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.model.AsyncProcessObjectRequest;
import com.aliyun.oss.model.AsyncProcessObjectResult;
import com.aliyuncs.exceptions.ClientException;

import java.util.Base64;

public class Demo1 {
    public static void main(String[] args) throws ClientException {
        // Specify the endpoint of the region in which the bucket is located.
        String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
        // Specify the ID of the Alibaba Cloud region in which the bucket is located. Example: cn-hangzhou.
        String region = "cn-hangzhou";
        // Obtain a credential from the environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured.
        EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
        // Specify the name of the bucket.
        String bucketName = "examplebucket";
        // Specify the name of the output object.
        String targetKey = "dest.png";
        // Specify the name of the source document.
        String sourceKey = "src.docx";

        // Create an OSSClient instance.
        // When the OSSClient instance is no longer in use, call the shutdown method to release resources.
        ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
        clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);
        OSS ossClient = OSSClientBuilder.create()
                .endpoint(endpoint)
                .credentialsProvider(credentialsProvider)
                .clientConfiguration(clientBuilderConfiguration)
                .region(region)
                .build();

        try {
            // Create a style variable of the string type to store document conversion parameters.
            String style = String.format("doc/convert,target_png,source_docx");
            // Create an asynchronous processing instruction.
            String bucketEncoded = Base64.getUrlEncoder().withoutPadding().encodeToString(bucketName.getBytes());
            String targetEncoded = Base64.getUrlEncoder().withoutPadding().encodeToString(targetKey.getBytes());
            String process = String.format("%s|sys/saveas,b_%s,o_%s/notify,topic_dGVzdC10b3BpYw", style, bucketEncoded, targetEncoded);
            // Create an AsyncProcessObjectRequest object.
            AsyncProcessObjectRequest request = new AsyncProcessObjectRequest(bucketName, sourceKey, process);
            // Execute the asynchronous processing task.
            AsyncProcessObjectResult response = ossClient.asyncProcessObject(request);
            System.out.println("EventId: " + response.getEventId());
            System.out.println("RequestId: " + response.getRequestId());
            System.out.println("TaskId: " + response.getTaskId());

        } finally {
            // Close your OSSClient.
            ossClient.shutdown();
        }
    }
}

# -*- coding: utf-8 -*-
import base64
import oss2
from oss2.credentials import EnvironmentVariableCredentialsProvider

def main():
    # Obtain the temporary access credentials from the environment variables. Before you execute the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured.
    auth = oss2.ProviderAuthV4(EnvironmentVariableCredentialsProvider())
    # Specify the endpoint for the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com.
    endpoint = 'https://oss-cn-hangzhou.aliyuncs.com'
    # Specify the ID of the Alibaba Cloud region in which the bucket is located. Example: cn-hangzhou.
    region = 'cn-hangzhou'

    # Specify the name of the bucket. Example: examplebucket.
    bucket = oss2.Bucket(auth, endpoint, 'examplebucket', region=region)

    # Specify the name of the source document.
    source_key = 'src.docx'

    # Specify the name of the output object.
    target_key = 'dest.png'

    # Create a style variable of the string type to store document conversion parameters.
    animation_style = 'doc/convert,target_png,source_docx'

    # Create a processing instruction, in which the name of the bucket and the name of the output object are Base64-encoded.
    bucket_name_encoded = base64.urlsafe_b64encode('examplebucket'.encode()).decode().rstrip('=')
    target_key_encoded = base64.urlsafe_b64encode(target_key.encode()).decode().rstrip('=')
    process = f"{animation_style}|sys/saveas,b_{bucket_name_encoded},o_{target_key_encoded}/notify,topic_dGVzdC10b3BpYw"

    try:
        # Execute the asynchronous processing task.
        result = bucket.async_process_object(source_key, process)
        print(f"EventId: {result.event_id}")
        print(f"RequestId: {result.request_id}")
        print(f"TaskId: {result.task_id}")
    except Exception as e:
        print(f"Error: {e}")


if __name__ == "__main__":
    main()

package main

import (
    "encoding/base64"
    "fmt"
    "os"
    "github.com/aliyun/aliyun-oss-go-sdk/oss"
    "log"
)

func main() {
    // Obtain the temporary access credentials from the environment variables. Before you execute the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured.
    provider, err := oss.NewEnvironmentVariableCredentialsProvider()
    if err != nil {
    fmt.Println("Error:", err)
    os.Exit(-1)
    }
    // Create an OSSClient instance.
    // Specify the endpoint of the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com. Specify your actual endpoint.
    // Specify the ID of the Alibaba Cloud region in which the bucket is located. Example: cn-hangzhou.
    client, err := oss.New("https://oss-cn-hangzhou.aliyuncs.com", "", "", oss.SetCredentialsProvider(&provider), oss.AuthVersion(oss.AuthV4), oss.Region("cn-hangzhou"))
    if err != nil {
    fmt.Println("Error:", err)
    os.Exit(-1)
    }
    // Specify the name of the bucket. Example: examplebucket.
    bucketName := "examplebucket"

    bucket, err := client.Bucket(bucketName)
    if err != nil {
    fmt.Println("Error:", err)
    os.Exit(-1)
    }

    // Specify the name of the source document.
    sourceKey := "src.docx"
    // Specify the name of the output object.
    targetKey := "dest.png"

    // Create a style variable of the string type to store document conversion parameters.
    animationStyle := "doc/convert,target_png,source_docx"

    // Create a processing instruction, in which the name of the bucket and the name of the output object are Base64-encoded.
    bucketNameEncoded := base64.URLEncoding.EncodeToString([]byte(bucketName))
    targetKeyEncoded := base64.URLEncoding.EncodeToString([]byte(targetKey))
    process := fmt.Sprintf("%s|sys/saveas,b_%v,o_%v/notify,topic_dGVzdC10b3BpYw", animationStyle, bucketNameEncoded, targetKeyEncoded)

    // Execute the asynchronous processing task.
    result, err := bucket.AsyncProcessObject(sourceKey, process)
    if err != nil {
    log.Fatalf("Failed to async process object: %s", err)
    }

    fmt.Printf("EventId: %s\n", result.EventId)
    fmt.Printf("RequestId: %s\n", result.RequestId)
    fmt.Printf("TaskId: %s\n", result.TaskId)
}

Related APIs

If your business requires a high level of customization, you can directly call RESTful APIs. To directly call a RESTful API, you must include the signature calculation in your code. For information about how to calculate the Authorization header, see Signature Version 4 (Recommended).

// Convert the example.docx file to PNG format image files.
POST /example.docx?x-oss-async-process HTTP/1.1
Host: doc-demo.oss-cn-hangzhou.aliyuncs.com
Date: Fri, 28 Oct 2022 06:40:10 GMT
Authorization: SignatureValue

x-oss-async-process=doc/convert,target_png,source_docx|sys/saveas,b_dGVzdC1idWNrZXQ=,o_ZG9jX2ltYWdlcy97aW5kZXh9LnBuZw==/notify,topic_dGVzdC10b3BpYw

Notes

• Document conversion supports only asynchronous processing (x-oss-async-process).

• Anonymous access is not supported.

• The maximum file size supported for document format conversion is 200 MB, which cannot be adjusted.

FAQ

References

For more information, see Document format conversion.