将 Firebase 存储下载 URL 推送到 Firebase 云 Firestore

Posted 2023-02-22

【中文标题】将 Firebase 存储下载 URL 推送到 Firebase 云 Firestore

【英文标题】：Pushing Firebase storage download URLs to Firebase cloud Firestore

【发布时间】：2019-11-15 04:44:30

【问题描述】：

如何将 Firebase 存储文件的下载 URL 推送到 Firestore 云？我有一个项目可以将 PDF 文件上传到 Firestore 存储，但我无法将上传文件的下载 URL 推送到 Firestore 云。

我需要捕获每个文件的上传 URL 并将其发送到 firestore 中的文档以便能够下载它。我正在上传和下载 PDF 文件。

这是我的代码：

public class pdfUploader extends AppCompatActivity 
    private StorageReference mStorageRef;
    Button upload;
    Button select;
    int CODE=215;
    private CollectionReference dbFirestore;

    @Override
    protected void onCreate(Bundle savedInstanceState) 
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_pdf_uploader);
        mStorageRef = FirebaseStorage.getInstance().getReference();
        upload = findViewById(R.id.upload);
        select = findViewById(R.id.choose);
        select.setOnClickListener(new View.OnClickListener() 
            @Override
            public void onClick(View v) 
                selectFile();
            
        );
    

    public void selectFile () 
        Intent i = new Intent(Intent.ACTION_GET_CONTENT);
        i.setType("*/*");
        startActivityForResult(Intent.createChooser(i,"Select a file"), CODE);
    

    protected void onActivityResult(int requestCode, int resultCode, Intent data) 
        String filePath = data.getDataString();
        Uri SelectedFileLocation=Uri.parse(filePath);
        UploadFile(SelectedFileLocation);
        super.onActivityResult(requestCode, resultCode, data);
    

    public  void UploadFile( Uri file) 
        Toast.makeText(this, "Please wait.. the file is uploading!", Toast.LENGTH_SHORT).show();
        //Uri file = Uri.fromFile(new File("path/to/images/rivers.jpg"));
        StorageReference riversRef = mStorageRef.child(Objects.requireNonNull(file.getLastPathSegment()));
        riversRef.putFile(file)
            .addOnSuccessListener(new OnSuccessListener<UploadTask.TaskSnapshot>() 
                @Override
                public void onSuccess(UploadTask.TaskSnapshot taskSnapshot) 
                    Toast.makeText(pdfUploader.this, "Upload Success", Toast.LENGTH_SHORT).show();
                
            ).addOnFailureListener(new OnFailureListener() 
                @Override
                public void onFailure(@NonNull Exception exception) 
                    Toast.makeText(pdfUploader.this, "Upload Failed", Toast.LENGTH_SHORT).show();

                
            );
    

【参考方案1】：

将此变量分配在顶部

FirebaseFirestore db;

//In oncreateView we have to assign now db so.
db = FirebaseFirestore.getInstance();

获取文件 uri 的代码：

riversRef.putFile(File).addOnSuccessListener(new OnSuccessListener<UploadTask.TaskSnapshot>() 
    @Override
    public void onSuccess(UploadTask.TaskSnapshot taskSnapshot)
    
        riversRef.getDownloadUrl().addOnSuccessListener(new OnSuccessListener<Uri>() 
                @Override
                public void onSuccess(Uri uri) 
                    Uri downloadUrl = uri;
                    Toast.makeText(MtActivity.this, "Upload Done", Toast.LENGTH_LONG).show();   
                    //After upload Complete we have to store the Data to firestore.
                    Map<String, Object> file = new HashMap<>();
                    file.put("url", downloadUrl.toString()); // We are using it as String because our data type in Firestore will be String
                    db.collection("/*Put you're collection name*/").document("/*And Document name Here*/")
                            .set(file)
                            .addOnSuccessListener(new OnSuccessListener<Void>() 
                                @Override
                                public void onSuccess(Void aVoid) 
                                    Log.d(TAG, "DocumentSnapshot successfully written!");
                                
                            )
                            .addOnFailureListener(new OnFailureListener() 
                                @Override
                                public void onFailure(@NonNull Exception e) 
                                    Log.w(TAG, "Error writing document", e);
                                
                            );
                
    
);

如果下载 url 过期，有更好的方法将您的图像文件存储在您的存储和 Firestore 中

代码：

riversRef.putFile(file)
                .addOnSuccessListener(new OnSuccessListener<UploadTask.TaskSnapshot>() 
                    @Override
                    public void onSuccess(UploadTask.TaskSnapshot taskSnapshot) 
                        String path = //Put path of storage it will be something like [images/filename.jpg(Put your extension of file)] this path from firebase storage
                        Map<String, Object> file = new HashMap<>();
                        file.put("url", path); // We are using it as String because our data type in Firestore will be String
                        db.collection("/*Put you're collection name*/").document("/*And Document id Here*/")
                                .set(file)
                                .addOnSuccessListener(new OnSuccessListener<Void>() 
                                    @Override
                                    public void onSuccess(Void aVoid) 
                                        Log.d(TAG, "DocumentSnapshot successfully written!");
                                    
                                )
                                .addOnFailureListener(new OnFailureListener() 
                                    @Override
                                    public void onFailure(@NonNull Exception e) 
                                        Log.w(TAG, "Error writing document", e);
                                    
                                );
                    
                )
                .addOnFailureListener(new OnFailureListener() 
                    @Override
                    public void onFailure(@NonNull Exception exception) 
                        Toast.makeText(pdfUploader.this, "Upload Failed", Toast.LENGTH_SHORT).show();

                    
                );

当您处理图像时，上面的代码会更好用，请阅读docs 了解更多详情

【讨论】：

我有另一个想法，如果你愿意，最好上传带有文档 ID 的文件

谢谢，运行在无法解析符号 'filepath' 的问题中，当创建局部变量时它会说在空对象上运行，我在 biggner 级别 sry for selly quastions

另外，我想保留自动生成的文档名称

已解决！你的回答是绝对正确的，我通过添加：- \\ Task downloadUrl = taskSnapshot.getStorage().getDownloadUrl(); .

请务必记住，当您存储 Firebase 存储 URL 时，它们可能包含过期的身份验证令牌。最好也保存文件的 ID，这样当 URL 过期时，您可以再次调用 getDownloadUrl() 来刷新 URL。在正常操作中，令牌不应过期，但您可以从 Firebase 控制台使下载 URL 中的所有令牌失效，因此无论如何您最好做好准备。